老年人心臟性猝死是指急性癥狀發作后1小時內發生的以意識突然喪失為特征的由心臟原因引起(qi)的(de)(de)自然(ran)死(si)(si)亡(wang)(wang)。1979年國際心臟病學(xue)會(hui)、美國心臟學(xue)會(hui)以及1970年世(shi)界衛(wei)生組(zu)織定義的(de)(de)猝死(si)(si)為:急性癥狀(zhuang)發生后(hou)即刻或(huo)者(zhe)情(qing)況24小時內發生的(de)(de)意(yi)外死(si)(si)亡(wang)(wang)。目前大多數學(xue)者(zhe)傾向于(yu)將猝死(si)(si)的(de)(de)時間限定在發病1小時內。其特點有三(san),①死(si)(si)亡(wang)(wang)急驟,②死(si)(si)亡(wang)(wang)出人意(yi)料,③自然(ran)死(si)(si)亡(wang)(wang)或(huo)非(fei)暴力死(si)(si)亡(wang)(wang)。
(1)冠心病
冠心病(bing)(bing)(急性(xing)(xing)缺血(xue)事件,慢性(xing)(xing)缺血(xue)性(xing)(xing)心臟(zang)(zang)病(bing)(bing))是(shi)心臟(zang)(zang)性(xing)(xing)猝死(si)(si)的(de)(de)最常見的(de)(de)原因。對心臟(zang)(zang)性(xing)(xing)猝死(si)(si)的(de)(de)尸檢(jian)發現,大約(yue)80%的(de)(de)患(huan)(huan)者具有不同(tong)程度的(de)(de)冠狀動脈病(bing)(bing)變(bian),大約(yue)2/3以上(shang)的(de)(de)患(huan)(huan)者為2支或3支以上(shang)的(de)(de)病(bing)(bing)變(bian)。心肌梗死(si)(si)后(hou)伴有左(zuo)心功(gong)能下降或嚴(yan)重室性(xing)(xing)心律失常的(de)(de)患(huan)(huan)者,心臟(zang)(zang)性(xing)(xing)猝死(si)(si)的(de)(de)發生(sheng)率顯(xian)著增加。
(2)心肌病
擴張型心(xin)(xin)(xin)肌(ji)病(bing)的(de)(de)心(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)猝(cu)(cu)死(si)率為(wei)2%,在(zai)伴有室性(xing)(xing)心(xin)(xin)(xin)律(lv)失常時心(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)猝(cu)(cu)死(si)率可明顯增加。而肥厚性(xing)(xing)心(xin)(xin)(xin)肌(ji)病(bing)患(huan)(huan)者(zhe)中心(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)猝(cu)(cu)死(si)更(geng)常見。大多數學者(zhe)報(bao)道,肥厚性(xing)(xing)心(xin)(xin)(xin)肌(ji)病(bing)的(de)(de)年(nian)病(bing)死(si)率為(wei)3%~4%,其中大多數為(wei)心(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)猝(cu)(cu)死(si)。在(zai)肥厚性(xing)(xing)心(xin)(xin)(xin)肌(ji)病(bing)患(huan)(huan)者(zhe),下(xia)列情形為(wei)發(fa)生(sheng)心(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)猝(cu)(cu)死(si)的(de)(de)高危(wei)因(yin)素:①年(nian)齡較輕,在(zai)30歲以下(xia)。②曾有暈厥(jue)病(bing)史(shi)。③既(ji)往有心(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)猝(cu)(cu)死(si)的(de)(de)家族史(shi)。此外,各種(zhong)原因(yin)產生(sheng)的(de)(de)心(xin)(xin)(xin)肌(ji)病(bing)和致心(xin)(xin)(xin)律(lv)失常性(xing)(xing)心(xin)(xin)(xin)肌(ji)病(bing)也容易發(fa)生(sheng)心(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)(xing)猝(cu)(cu)死(si)。
(3)心(xin)臟(zang)瓣膜炎癥(zheng)浸潤(run)
現已公認,二(er)尖瓣(ban)脫垂綜合征可發生心臟性(xing)猝死,但發生率不高。據(ju)Jersaty報道,二(er)尖瓣(ban)脫垂患者伴有(you)(you)(you)(you)下列情形者易發生心臟性(xing)猝死:①40歲左(zuo)右的女性(xing)患者。②有(you)(you)(you)(you)暈厥(jue)病史。③心電圖上有(you)(you)(you)(you)ST段改(gai)變或(huo)有(you)(you)(you)(you)頻發室性(xing)期(qi)前(qian)收縮等室性(xing)心律失(shi)常。④有(you)(you)(you)(you)“喀啦”音和收縮晚期(qi)或(huo)全收縮期(qi)雜音。
(4)心律失常
一般不(bu)易發(fa)生心臟性(xing)猝死,但在老年(nian)患者,常可(ke)并發(fa)嚴重的冠(guan)狀(zhuang)動(dong)脈狹(xia)窄或高血壓(ya)致(zhi)嚴重左心室(shi)肥厚型心肌病的左心室(shi)流出(chu)道梗阻時,快速性(xing)室(shi)上性(xing)心律失常發(fa)作時也易發(fa)生心臟性(xing)猝死。
多數學者(zhe)(zhe)認為(wei)(wei),嚴(yan)(yan)重(zhong)的(de)(de)(de)(de)(de)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)常(chang)(chang)可發(fa)(fa)生心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si),尤其在(zai)患(huan)(huan)有(you)(you)嚴(yan)(yan)重(zhong)器(qi)質性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)病的(de)(de)(de)(de)(de)老年患(huan)(huan)者(zhe)(zhe)。目(mu)前(qian)(qian)(qian),室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)(qian)(qian)收(shou)(shou)縮(suo)在(zai)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)中的(de)(de)(de)(de)(de)意義尚(shang)存爭議。有(you)(you)些學者(zhe)(zhe)發(fa)(fa)現(xian),室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)(qian)(qian)收(shou)(shou)縮(suo)并(bing)不能增(zeng)加心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)的(de)(de)(de)(de)(de)發(fa)(fa)生率(lv),尤其是(shi)(shi)(shi)無(wu)明顯器(qi)質性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)病基礎的(de)(de)(de)(de)(de)單(dan)純(chun)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)(qian)(qian)收(shou)(shou)縮(suo)。但(dan)也(ye)(ye)有(you)(you)一(yi)(yi)些研究提示,室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)(qian)(qian)收(shou)(shou)縮(suo)本身即(ji)是(shi)(shi)(shi)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)的(de)(de)(de)(de)(de)危(wei)(wei)(wei)險因素,特別(bie)是(shi)(shi)(shi)嚴(yan)(yan)重(zhong)的(de)(de)(de)(de)(de)冠狀動脈病變(bian)(bian)或(huo)(huo)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌梗死(si)(si)后的(de)(de)(de)(de)(de)患(huan)(huan)者(zhe)(zhe),頻發(fa)(fa)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)(qian)(qian)收(shou)(shou)縮(suo)對心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)的(de)(de)(de)(de)(de)發(fa)(fa)生具有(you)(you)一(yi)(yi)定的(de)(de)(de)(de)(de)意義,特別(bie)是(shi)(shi)(shi)合并(bing)有(you)(you)左(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)肥厚、室(shi)(shi)(shi)內(nei)傳(chuan)導阻滯和ST-T改變(bian)(bian)者(zhe)(zhe)。而室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)動過速(su)在(zai)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)中的(de)(de)(de)(de)(de)意義比室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)(qian)(qian)收(shou)(shou)縮(suo)為(wei)(wei)大(da)(da)。在(zai)臨床(chuang)中,我(wo)們常(chang)(chang)把室(shi)(shi)(shi)速(su)或(huo)(huo)成對、多源及頻發(fa)(fa)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)(qian)(qian)收(shou)(shou)縮(suo)稱為(wei)(wei)復雜性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)常(chang)(chang)。Morganroth根據復雜性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)常(chang)(chang)引起心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)的(de)(de)(de)(de)(de)危(wei)(wei)(wei)險程(cheng)度,將復雜性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)常(chang)(chang)分為(wei)(wei)良性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)占(zhan)(zhan)30%,其左(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)功能和血(xue)流(liu)動力學均(jun)正常(chang)(chang),發(fa)(fa)生心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)的(de)(de)(de)(de)(de)危(wei)(wei)(wei)險性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)極(ji)小;潛(qian)在(zai)惡(e)(e)(e)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)占(zhan)(zhan)65%,心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)結(jie)構(gou)輕度異常(chang)(chang),有(you)(you)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)功能不全和室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)異位激(ji)動,如(ru)(ru)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)期(qi)(qi)前(qian)(qian)(qian)收(shou)(shou)縮(suo)和(或(huo)(huo))非持續性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)速(su),無(wu)血(xue)流(liu)動力學障礙(ai),但(dan)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)的(de)(de)(de)(de)(de)危(wei)(wei)(wei)險性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)增(zeng)加;惡(e)(e)(e)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)常(chang)(chang)占(zhan)(zhan)5%,幾(ji)乎都有(you)(you)血(xue)流(liu)動力學表現(xian)和體(ti)征(zheng)(暈厥(jue),心(xin)(xin)(xin)(xin)(xin)(xin)(xin)功能不全,心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌缺血(xue)或(huo)(huo)低血(xue)壓)其發(fa)(fa)生心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)的(de)(de)(de)(de)(de)危(wei)(wei)(wei)險性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)最大(da)(da)。臨床(chuang)上常(chang)(chang)見(jian)5種類(lei)型:①心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)率(lv)≥230bpm的(de)(de)(de)(de)(de)持續性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)單(dan)形性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)速(su)。②心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)率(lv)逐漸(jian)加速(su)的(de)(de)(de)(de)(de)室(shi)(shi)(shi)速(su)或(huo)(huo)可蛻變(bian)(bian)為(wei)(wei)室(shi)(shi)(shi)撲(pu)和(或(huo)(huo))室(shi)(shi)(shi)顫趨勢者(zhe)(zhe)。③室(shi)(shi)(shi)速(su)伴嚴(yan)(yan)重(zhong)血(xue)流(liu)動力學障礙(ai)如(ru)(ru)暈厥(jue),左(zuo)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)功能不全和低血(xue)壓。④多形性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(包括長Q-T綜(zong)(zong)合征(zheng)合并(bing)的(de)(de)(de)(de)(de)尖端扭轉(zhuan)型)室(shi)(shi)(shi)速(su)。⑤室(shi)(shi)(shi)撲(pu)和(或(huo)(huo))室(shi)(shi)(shi)顫起始(shi)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)常(chang)(chang)即(ji)為(wei)(wei)室(shi)(shi)(shi)撲(pu)和(或(huo)(huo))室(shi)(shi)(shi)顫(如(ru)(ru)特發(fa)(fa)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)顫,Brugada綜(zong)(zong)合征(zheng))。臨床(chuang)表現(xian)為(wei)(wei)阿(a)-斯綜(zong)(zong)合征(zheng)發(fa)(fa)作。而由(you)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)電圖證(zheng)實(shi)的(de)(de)(de)(de)(de)大(da)(da)多數心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)發(fa)(fa)作(65%~85%)是(shi)(shi)(shi)由(you)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)顫動之類(lei)的(de)(de)(de)(de)(de)惡(e)(e)(e)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)常(chang)(chang)所(suo)致。但(dan)緩(huan)慢性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)常(chang)(chang)也(ye)(ye)可能是(shi)(shi)(shi)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)(zang)性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)猝(cu)(cu)(cu)死(si)(si)的(de)(de)(de)(de)(de)潛(qian)在(zai)原因,并(bing)可能在(zai)記錄到緩(huan)慢性(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)(shi)常(chang)(chang)之前(qian)(qian)(qian)就(jiu)已轉(zhuan)變(bian)(bian)為(wei)(wei)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)(shi)顫動。
預激綜合征患(huan)者并發房(fang)室折(zhe)返性心(xin)動(dong)過速、心(xin)房(fang)顫動(dong)等快速性心(xin)律失常者占40%~80%。但(dan)發生心(xin)臟性猝死的(de)危險性較低(di),有(you)調查在4%以下(xia),老年患(huan)者也未見(jian)心(xin)臟性猝死增加的(de)報道(dao)。
(5)其他
糖尿病除了(le)增(zeng)加(jia)(jia)冠心病的(de)發生率外,本身也可損傷心肌而(er)增(zeng)加(jia)(jia)心臟(zang)性猝死的(de)發生率。尤(you)其(qi)女性患者(zhe)(zhe)的(de)心臟(zang)性猝死發生率增(zeng)加(jia)(jia)更明顯,較同(tong)年齡組(zu)而(er)無(wu)糖尿病的(de)患者(zhe)(zhe)增(zeng)加(jia)(jia)3倍。
目前已(yi)知(zhi),發生(sheng)心(xin)(xin)(xin)臟性(xing)猝(cu)死的機制主(zhu)要為嚴重的室性(xing)心(xin)(xin)(xin)律失(shi)常,包(bao)括室性(xing)心(xin)(xin)(xin)動(dong)過(guo)速(su),心(xin)(xin)(xin)室顫動(dong)等(deng)。也有(you)一部分(fen)人為突(tu)然發生(sheng)的嚴重血流動(dong)力學障(zhang)礙,心(xin)(xin)(xin)臟破(po)裂等(deng)。
一般認為(wei),心(xin)(xin)室顫(zhan)動(dong)(dong)是多發(fa)(fa)的(de)(de)折返小波引起(qi)的(de)(de)持續性(xing)快而不規則的(de)(de)心(xin)(xin)室激動(dong)(dong)。心(xin)(xin)室顫(zhan)動(dong)(dong)的(de)(de)發(fa)(fa)生必需包括以下幾個基本條件(jian),即異步(bu)和(he)分(fen)離(li)的(de)(de)局部(bu)波前(qian)興奮(fen),傳導延緩(huan)和(he)心(xin)(xin)室不應期縮(suo)短。這些變化,在缺血的(de)(de)心(xin)(xin)肌中均可出現(xian)。
(1)缺血性(xing)(xing)(xing)室性(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)(chang):包括急(ji)性(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)缺血所(suo)致的(de)(de)室性(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)(chang)和心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)梗(geng)死(si)后(hou)陳舊性(xing)(xing)(xing)病變并發的(de)(de)室性(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)(chang)。如果(guo)急(ji)性(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)缺血發生(sheng)在(zai)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)梗(geng)死(si)后(hou)瘢痕愈合的(de)(de)邊(bian)緣心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji),則室性(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)(chang)的(de)(de)發生(sheng)率更高。在(zai)急(ji)性(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)缺血時(shi),局部(bu)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)組織灌注不足,導(dao)致缺血部(bu)位的(de)(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)能(neng)量代謝較正常(chang)(chang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)組織明顯降低,大量游離(li)脂肪酸(FFA)堆積,細(xi)胞內(nei)乳酸含量增(zeng)加,細(xi)胞內(nei)鉀、鎂(mei)離(li)子外流,則靜息電(dian)位的(de)(de)負值進一(yi)步增(zeng)加,形成舒張期電(dian)位。同時(shi),動作電(dian)位的(de)(de)振幅下(xia)降,去極化的(de)(de)速度減慢(man),興奮傳導(dao)速度減慢(man),則心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)自律(lv)(lv)(lv)性(xing)(xing)(xing)增(zeng)強,并易于形成折返(fan)的(de)(de)條件而(er)發生(sheng)室性(xing)(xing)(xing)折返(fan)性(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)失(shi)常(chang)(chang)及心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)室顫動。而(er)同時(shi)存在(zai)左心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)功(gong)能(neng)不全的(de)(de)患者,心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)猝死(si)的(de)(de)發生(sheng)率則更高,尤其左室射血分數(shu)低于30%是心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)猝死(si)的(de)(de)最強的(de)(de)預測因素(su)。
現已知再(zai)灌(guan)(guan)(guan)注(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)是發(fa)(fa)生(sheng)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)(xing)(xing)(xing)(xing)(xing)猝死的(de)(de)(de)(de)(de)(de)重要機(ji)(ji)制(zhi)(zhi)(zhi)。再(zai)灌(guan)(guan)(guan)注(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)可(ke)見(jian)于冠(guan)狀動(dong)(dong)(dong)(dong)(dong)脈(mo)(mo)痙攣緩解(jie)以后(hou)(hou),也(ye)可(ke)見(jian)于急性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)梗死溶栓治(zhi)療或(huo)(huo)機(ji)(ji)械性(xing)(xing)(xing)(xing)(xing)(xing)粉碎斑塊后(hou)(hou)使(shi)完全閉(bi)塞的(de)(de)(de)(de)(de)(de)血(xue)管再(zai)通等情況。常(chang)在冠(guan)狀動(dong)(dong)(dong)(dong)(dong)脈(mo)(mo)再(zai)通后(hou)(hou)幾秒鐘而(er)(er)出現再(zai)灌(guan)(guan)(guan)注(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)。許多(duo)研究表明,冠(guan)狀動(dong)(dong)(dong)(dong)(dong)脈(mo)(mo)再(zai)通時,再(zai)灌(guan)(guan)(guan)注(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)的(de)(de)(de)(de)(de)(de)發(fa)(fa)生(sheng)率高達82%。在再(zai)灌(guan)(guan)(guan)注(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)的(de)(de)(de)(de)(de)(de)不(bu)(bu)同類型中60%~80%為(wei)(wei)加(jia)速(su)性(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)自主心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv)和(he)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)期前(qian)收縮,可(ke)引(yin)(yin)起(qi)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)(xing)(xing)(xing)(xing)(xing)猝死的(de)(de)(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)為(wei)(wei)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)(dong)(dong)(dong)(dong)過(guo)速(su)和(he)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)顫動(dong)(dong)(dong)(dong)(dong),嚴重的(de)(de)(de)(de)(de)(de)緩慢性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)也(ye)可(ke)引(yin)(yin)起(qi)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)(xing)(xing)(xing)(xing)(xing)猝死。而(er)(er)再(zai)灌(guan)(guan)(guan)注(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)的(de)(de)(de)(de)(de)(de)類型和(he)冠(guan)狀動(dong)(dong)(dong)(dong)(dong)脈(mo)(mo)的(de)(de)(de)(de)(de)(de)再(zai)通部(bu)位(wei)有(you)一定的(de)(de)(de)(de)(de)(de)關系。左(zuo)前(qian)降支和(he)左(zuo)旋支再(zai)灌(guan)(guan)(guan)注(zhu)時易(yi)發(fa)(fa)生(sheng)加(jia)速(su)性(xing)(xing)(xing)(xing)(xing)(xing)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)自主心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv),室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)(dong)(dong)(dong)(dong)過(guo)速(su)和(he)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)顫動(dong)(dong)(dong)(dong)(dong)。右冠(guan)狀動(dong)(dong)(dong)(dong)(dong)脈(mo)(mo)阻塞再(zai)灌(guan)(guan)(guan)注(zhu)時易(yi)發(fa)(fa)生(sheng)竇性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)(dong)(dong)(dong)(dong)過(guo)緩,房室(shi)(shi)傳導阻滯。實驗研究提示,再(zai)灌(guan)(guan)(guan)注(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)的(de)(de)(de)(de)(de)(de)發(fa)(fa)生(sheng)機(ji)(ji)制(zhi)(zhi)(zhi)包括觸發(fa)(fa)激(ji)動(dong)(dong)(dong)(dong)(dong)、折返激(ji)動(dong)(dong)(dong)(dong)(dong)和(he)異位(wei)自律(lv)(lv)(lv)(lv)(lv)性(xing)(xing)(xing)(xing)(xing)(xing)增(zeng)高。目(mu)前(qian)多(duo)數學者認為(wei)(wei),觸發(fa)(fa)激(ji)動(dong)(dong)(dong)(dong)(dong)在再(zai)灌(guan)(guan)(guan)注(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)的(de)(de)(de)(de)(de)(de)發(fa)(fa)生(sheng)中占據重要位(wei)置。而(er)(er)折返機(ji)(ji)制(zhi)(zhi)(zhi)的(de)(de)(de)(de)(de)(de)產生(sheng)可(ke)能與(yu)再(zai)灌(guan)(guan)(guan)注(zhu)后(hou)(hou)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)細胞(bao)電生(sheng)理恢(hui)復不(bu)(bu)均(jun)勻(yun)有(you)關。心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)缺(que)血(xue)性(xing)(xing)(xing)(xing)(xing)(xing)損傷(shang)使(shi)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)細胞(bao)的(de)(de)(de)(de)(de)(de)電生(sheng)理改變不(bu)(bu)均(jun)勻(yun),血(xue)管再(zai)通后(hou)(hou)的(de)(de)(de)(de)(de)(de)再(zai)灌(guan)(guan)(guan)注(zhu)使(shi)血(xue)流恢(hui)復,但(dan)恢(hui)復血(xue)流后(hou)(hou)的(de)(de)(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)細胞(bao)血(xue)液供(gong)應和(he)代謝恢(hui)復也(ye)不(bu)(bu)均(jun)勻(yun),結果導致缺(que)血(xue)區內心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)應激(ji)性(xing)(xing)(xing)(xing)(xing)(xing)的(de)(de)(de)(de)(de)(de)恢(hui)復程度不(bu)(bu)一致,則(ze)易(yi)于形成折返而(er)(er)引(yin)(yin)起(qi)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)(dong)(dong)(dong)(dong)過(guo)速(su)和(he)(或(huo)(huo))心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)顫動(dong)(dong)(dong)(dong)(dong)。此外,心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)缺(que)血(xue)-再(zai)灌(guan)(guan)(guan)注(zhu)損傷(shang)也(ye)可(ke)引(yin)(yin)起(qi)異位(wei)興奮灶(zao)的(de)(de)(de)(de)(de)(de)自律(lv)(lv)(lv)(lv)(lv)性(xing)(xing)(xing)(xing)(xing)(xing)增(zeng)加(jia),引(yin)(yin)起(qi)室(shi)(shi)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)。Pogwizd等用心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)三維(wei)標測技術(shu)研究表明,75%的(de)(de)(de)(de)(de)(de)再(zai)灌(guan)(guan)(guan)注(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)是由觸發(fa)(fa)激(ji)動(dong)(dong)(dong)(dong)(dong)引(yin)(yin)起(qi)的(de)(de)(de)(de)(de)(de),25%的(de)(de)(de)(de)(de)(de)再(zai)灌(guan)(guan)(guan)注(zhu)性(xing)(xing)(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)(lv)(lv)(lv)失(shi)(shi)常(chang)是由折返機(ji)(ji)制(zhi)(zhi)(zhi)引(yin)(yin)起(qi)。
病因(yin)不明,無明顯冠狀動脈或(huo)(huo)心(xin)(xin)肌本身的(de)病變,常常突(tu)然或(huo)(huo)在某些誘因(yin)的(de)作用下發(fa)生(sheng)嚴重(zhong)的(de)室性(xing)(xing)心(xin)(xin)律失常和(或(huo)(huo))心(xin)(xin)室顫動,而發(fa)生(sheng)心(xin)(xin)臟性(xing)(xing)猝死。研究(jiu)表明,原發(fa)性(xing)(xing)室性(xing)(xing)心(xin)(xin)律失常的(de)發(fa)生(sheng)機(ji)制多(duo)為觸發(fa)激動,也(ye)有的(de)為折返(fan)機(ji)制。
Raizes等(deng)(deng)研究表明,非(fei)心(xin)(xin)(xin)(xin)律(lv)失常(chang)引起的(de)(de)(de)心(xin)(xin)(xin)(xin)臟性(xing)(xing)猝(cu)死(si)(si)(si)只占0.56%,包括心(xin)(xin)(xin)(xin)臟或(huo)主動(dong)(dong)脈(mo)破裂,心(xin)(xin)(xin)(xin)肌梗死(si)(si)(si)擴展,交感神經反射性(xing)(xing)抑制,以(yi)及(ji)各(ge)種(zhong)原因(yin)(yin)引起的(de)(de)(de)心(xin)(xin)(xin)(xin)臟嚴(yan)重的(de)(de)(de)機(ji)(ji)械性(xing)(xing)梗阻等(deng)(deng)。尤其伴(ban)有(you)左心(xin)(xin)(xin)(xin)功(gong)能(neng)(neng)(neng)(neng)不全(quan)的(de)(de)(de)患者(zhe)(zhe)心(xin)(xin)(xin)(xin)臟性(xing)(xing)猝(cu)死(si)(si)(si)的(de)(de)(de)發生率(lv)最高。左心(xin)(xin)(xin)(xin)功(gong)能(neng)(neng)(neng)(neng)不全(quan)又常(chang)有(you)冠狀動(dong)(dong)脈(mo)病(bing)(bing)變(bian)和(he)彌漫(man)的(de)(de)(de)心(xin)(xin)(xin)(xin)肌病(bing)(bing)變(bian),因(yin)(yin)而可(ke)伴(ban)有(you)急性(xing)(xing)心(xin)(xin)(xin)(xin)肌缺(que)血(xue)(xue)或(huo)心(xin)(xin)(xin)(xin)肌瘢痕組織所(suo)誘發的(de)(de)(de)惡性(xing)(xing)心(xin)(xin)(xin)(xin)律(lv)失常(chang),從而導致(zhi)心(xin)(xin)(xin)(xin)臟性(xing)(xing)猝(cu)死(si)(si)(si)。在(zai)冠心(xin)(xin)(xin)(xin)病(bing)(bing)合并(bing)左心(xin)(xin)(xin)(xin)室功(gong)能(neng)(neng)(neng)(neng)不全(quan)致(zhi)心(xin)(xin)(xin)(xin)臟性(xing)(xing)猝(cu)死(si)(si)(si)事件中,36%表現(xian)(xian)為(wei)嚴(yan)重心(xin)(xin)(xin)(xin)動(dong)(dong)過(guo)緩(huan)或(huo)電(dian)-機(ji)(ji)械分(fen)離。心(xin)(xin)(xin)(xin)臟驟(zou)停前并(bing)未(wei)伴(ban)心(xin)(xin)(xin)(xin)力(li)(li)衰(shuai)竭癥狀的(de)(de)(de)惡化。緩(huan)慢性(xing)(xing)心(xin)(xin)(xin)(xin)律(lv)失常(chang)或(huo)電(dian)-機(ji)(ji)械分(fen)離可(ke)能(neng)(neng)(neng)(neng)因(yin)(yin)左室收縮(suo)功(gong)能(neng)(neng)(neng)(neng)衰(shuai)竭終末期心(xin)(xin)(xin)(xin)室壁應激時使心(xin)(xin)(xin)(xin)室內壓力(li)(li)和(he)容(rong)量突然增加,而周圍血(xue)(xue)管收縮(suo)同時出(chu)現(xian)(xian)障礙,不能(neng)(neng)(neng)(neng)維持體循環血(xue)(xue)壓,以(yi)至(zhi)虛(xu)脫和(he)暈厥。猝(cu)死(si)(si)(si)則(ze)為(wei)血(xue)(xue)流動(dong)(dong)力(li)(li)學障礙所(suo)致(zhi),并(bing)非(fei)心(xin)(xin)(xin)(xin)電(dian)不穩定(ding)事件。另一(yi)部分(fen)左心(xin)(xin)(xin)(xin)功(gong)能(neng)(neng)(neng)(neng)不全(quan)的(de)(de)(de)患者(zhe)(zhe)伴(ban)有(you)室性(xing)(xing)心(xin)(xin)(xin)(xin)動(dong)(dong)過(guo)速,則(ze)可(ke)能(neng)(neng)(neng)(neng)為(wei)心(xin)(xin)(xin)(xin)律(lv)失常(chang)所(suo)致(zhi)。
(2)心臟性猝死(si)后的病(bing)生(sheng)理變(bian)化(hua)
原發(fa)(fa)性改(gai)變(bian):心(xin)(xin)(xin)臟(zang)(zang)性猝(cu)(cu)死(si)(si)(si)的(de)(de)(de)(de)心(xin)(xin)(xin)臟(zang)(zang)病(bing)(bing)理(li)改(gai)變(bian)資料(liao)主要來自(zi)尸體解(jie)(jie)剖(pou)。但不(bu)同學者(zhe)(zhe)(zhe)所(suo)報道(dao)(dao)的(de)(de)(de)(de)尸體解(jie)(jie)剖(pou)病(bing)(bing)理(li)結果有很大(da)的(de)(de)(de)(de)不(bu)一致,且多(duo)數學者(zhe)(zhe)(zhe)研(yan)究(jiu)為冠(guan)(guan)心(xin)(xin)(xin)病(bing)(bing)猝(cu)(cu)死(si)(si)(si)。從冠(guan)(guan)心(xin)(xin)(xin)病(bing)(bing)猝(cu)(cu)死(si)(si)(si)的(de)(de)(de)(de)病(bing)(bing)理(li)資料(liao)來看,主要病(bing)(bing)理(li)結果為冠(guan)(guan)狀動脈狹窄程度重,冠(guan)(guan)狀動脈內(nei)并發(fa)(fa)血栓(shuan)形(xing)成,心(xin)(xin)(xin)肌(ji)出現(xian)嚴重的(de)(de)(de)(de)缺血或梗死(si)(si)(si)。Schwartz等(deng)發(fa)(fa)現(xian),1/3以(yi)上的(de)(de)(de)(de)冠(guan)(guan)心(xin)(xin)(xin)病(bing)(bing)猝(cu)(cu)死(si)(si)(si)患(huan)者(zhe)(zhe)(zhe)的(de)(de)(de)(de)冠(guan)(guan)狀動脈內(nei)有血栓(shuan)形(xing)成。國內(nei)外的(de)(de)(de)(de)一些(xie)資料(liao)提示:冠(guan)(guan)心(xin)(xin)(xin)病(bing)(bing)猝(cu)(cu)死(si)(si)(si)患(huan)者(zhe)(zhe)(zhe)中急性心(xin)(xin)(xin)肌(ji)梗死(si)(si)(si)的(de)(de)(de)(de)發(fa)(fa)生(sheng)(sheng)率約為40%,并且冠(guan)(guan)心(xin)(xin)(xin)病(bing)(bing)猝(cu)(cu)死(si)(si)(si)患(huan)者(zhe)(zhe)(zhe)的(de)(de)(de)(de)竇房結和傳(chuan)導(dao)系統并無明(ming)(ming)顯的(de)(de)(de)(de)急性病(bing)(bing)變(bian),亦證實了冠(guan)(guan)心(xin)(xin)(xin)病(bing)(bing)猝(cu)(cu)死(si)(si)(si)的(de)(de)(de)(de)發(fa)(fa)生(sheng)(sheng)機制為心(xin)(xin)(xin)電不(bu)穩(wen)定所(suo)致。心(xin)(xin)(xin)臟(zang)(zang)性猝(cu)(cu)死(si)(si)(si)很少發(fa)(fa)生(sheng)(sheng)在沒有器質性心(xin)(xin)(xin)臟(zang)(zang)病(bing)(bing)的(de)(de)(de)(de)患(huan)者(zhe)(zhe)(zhe)。有些(xie)患(huan)者(zhe)(zhe)(zhe)發(fa)(fa)生(sheng)(sheng)心(xin)(xin)(xin)臟(zang)(zang)性猝(cu)(cu)死(si)(si)(si)后,即使心(xin)(xin)(xin)臟(zang)(zang)的(de)(de)(de)(de)大(da)體檢查無明(ming)(ming)顯肉(rou)眼(yan)病(bing)(bing)變(bian),但可能其心(xin)(xin)(xin)臟(zang)(zang)的(de)(de)(de)(de)分子結構(gou)(gou)和功能也存(cun)在著(zhu)明(ming)(ming)顯的(de)(de)(de)(de)異(yi)常。如離子通道(dao)(dao)、蛋(dan)白質結構(gou)(gou)異(yi)常等(deng)。
繼發性改(gai)變:正(zheng)常心(xin)(xin)臟(zang)做功(gong)所需能(neng)量首(shou)先來(lai)(lai)(lai)自脂肪(fang),約占心(xin)(xin)肌(ji)(ji)(ji)(ji)總耗氧量的(de)(de)67%,其次來(lai)(lai)(lai)自葡(pu)萄糖和(he)乳(ru)酸(suan)(suan)(suan),分別占17.9%和(he)16.46%,極(ji)少數來(lai)(lai)(lai)自醋酸(suan)(suan)(suan)、氨(an)基酸(suan)(suan)(suan)、丙(bing)酮酸(suan)(suan)(suan)等。同(tong)時心(xin)(xin)臟(zang)必須依(yi)賴ATP來(lai)(lai)(lai)維持其心(xin)(xin)室(shi)壁的(de)(de)張(zhang)力(li)和(he)收(shou)(shou)縮狀(zhuang)態。研究(jiu)表明,心(xin)(xin)肌(ji)(ji)(ji)(ji)缺(que)血缺(que)氧10s即可代謝底物(wu)耗竭,心(xin)(xin)臟(zang)即完(wan)全(quan)失去收(shou)(shou)縮功(gong)能(neng)。在(zai)常溫下,如(ru)果心(xin)(xin)肌(ji)(ji)(ji)(ji)缺(que)血3~4min,心(xin)(xin)肌(ji)(ji)(ji)(ji)內磷(lin)(lin)酸(suan)(suan)(suan)肌(ji)(ji)(ji)(ji)酸(suan)(suan)(suan)含量減(jian)少70%~75%,ATP減(jian)少15%。如(ru)在(zai)此(ci)期(qi)內進(jin)行(xing)(xing)有(you)效(xiao)的(de)(de)心(xin)(xin)肺復(fu)蘇(su),心(xin)(xin)肌(ji)(ji)(ji)(ji)供(gong)血改(gai)善,則心(xin)(xin)肌(ji)(ji)(ji)(ji)張(zhang)力(li)可完(wan)全(quan)恢復(fu);缺(que)血8~10min,心(xin)(xin)肌(ji)(ji)(ji)(ji)內磷(lin)(lin)酸(suan)(suan)(suan)肌(ji)(ji)(ji)(ji)酸(suan)(suan)(suan)和(he)ATP將(jiang)全(quan)部耗盡,如(ru)在(zai)此(ci)期(qi)內進(jin)行(xing)(xing)有(you)效(xiao)的(de)(de)心(xin)(xin)肺復(fu)蘇(su),心(xin)(xin)臟(zang)的(de)(de)收(shou)(shou)縮和(he)舒張(zhang)功(gong)能(neng)仍可恢復(fu),10min后才進(jin)行(xing)(xing)有(you)效(xiao)的(de)(de)心(xin)(xin)肺復(fu)蘇(su)者(zhe),復(fu)蘇(su)的(de)(de)成功(gong)機會顯著減(jian)少。
腦(nao)(nao):腦(nao)(nao)的(de)(de)能量(liang)代謝(xie)主要來自葡(pu)萄糖,但腦(nao)(nao)組織(zhi)(zhi)本身對葡(pu)萄糖的(de)(de)儲備很少,必須依(yi)賴于(yu)(yu)循環血(xue)(xue)(xue)液(ye)來供應。并(bing)且(qie)腦(nao)(nao)組織(zhi)(zhi)的(de)(de)代謝(xie)85%~90%為有氧(yang)代謝(xie),而無氧(yang)酵解只占腦(nao)(nao)組織(zhi)(zhi)代謝(xie)的(de)(de)5%~15%,所以,腦(nao)(nao)組織(zhi)(zhi)的(de)(de)代謝(xie)和(he)生(sheng)理功(gong)(gong)能的(de)(de)維持(chi)則完全依(yi)賴于(yu)(yu)有效(xiao)的(de)(de)血(xue)(xue)(xue)液(ye)供應。血(xue)(xue)(xue)液(ye)供應障(zhang)礙(ai)引起腦(nao)(nao)細胞(bao)功(gong)(gong)能的(de)(de)改變(bian)的(de)(de)基礎是(shi)缺(que)血(xue)(xue)(xue)缺(que)氧(yang)引起腦(nao)(nao)組織(zhi)(zhi)的(de)(de)原(yuan)發(fa)和(he)繼發(fa)損害(hai)。原(yuan)發(fa)損害(hai)為腦(nao)(nao)組織(zhi)(zhi)缺(que)血(xue)(xue)(xue)缺(que)氧(yang)時,ATP不(bu)能合成(cheng),細胞(bao)鈉泵功(gong)(gong)能喪失(shi)(shi)(shi),細胞(bao)內(nei)鈉離子(zi)不(bu)能轉(zhuan)運到細胞(bao)外,鉀離子(zi)不(bu)能從細胞(bao)內(nei)逸(yi)出,細胞(bao)膜電(dian)(dian)位發(fa)生(sheng)改變(bian),因(yin)此不(bu)能產(chan)(chan)生(sheng)電(dian)(dian)活動(dong),細胞(bao)也失(shi)(shi)(shi)去(qu)了產(chan)(chan)生(sheng)和(he)傳導(dao)沖動(dong)的(de)(de)功(gong)(gong)能。研究表(biao)明,在(zai)完全缺(que)氧(yang)情(qing)況下,20s后大腦(nao)(nao)皮(pi)質的(de)(de)生(sheng)物電(dian)(dian)活動(dong)完全消(xiao)失(shi)(shi)(shi),30~90s后小(xiao)腦(nao)(nao)和(he)延(yan)髓的(de)(de)生(sheng)物電(dian)(dian)活動(dong)完全消(xiao)失(shi)(shi)(shi)。而缺(que)血(xue)(xue)(xue)缺(que)氧(yang)所致(zhi)的(de)(de)繼發(fa)損害(hai)包括兩(liang)個方面:
A.細胞內電(dian)解質紊亂和(he)各(ge)種(zhong)代謝(xie)產物的堆積(ji)而使(shi)腦組織(zhi)腫(zhong)脹(zhang)和(he)腦水(shui)腫(zhong)。
B.腦(nao)組(zu)(zu)織的局部循環功能(neng)障(zhang)礙(ai)進(jin)一步加重(zhong)。已有研究(jiu)提(ti)示(shi),心臟(zang)驟停引(yin)起的腦(nao)組(zu)(zu)織缺(que)血(xue)缺(que)氧(yang)時,病變主(zhu)要在大腦(nao)海馬(ma)回(hui)先出現,如缺(que)血(xue)進(jin)一步加重(zhong),則迅速波及全(quan)腦(nao),包(bao)括腦(nao)干和延髓。而患(huan)者發生心臟(zang)性猝死后,如果能(neng)及時、有效地進(jin)行心肺復蘇,則腦(nao)組(zu)(zu)織的血(xue)流(liu)有可(ke)能(neng)恢復,但腦(nao)組(zu)(zu)織由(you)于(yu)受到完全(quan)缺(que)血(xue)缺(que)氧(yang)的影(ying)響,腦(nao)水腫和微循環障(zhang)礙(ai)將繼續發展。腦(nao)組(zu)(zu)織的缺(que)血(xue)缺(que)氧(yang)時間長短直接影(ying)響大腦(nao)功能(neng)的恢復及患(huan)者的臨(lin)床預后。
腎:
心臟驟停時(shi),腎臟的(de)血流供應(ying)和濾過功(gong)能(neng)完全停止。首先受(shou)累(lei)的(de)是腎小(xiao)管,引起(qi)腎小(xiao)管細胞壞死,并逐步累(lei)及基(ji)(ji)底(di)膜及整(zheng)個腎單位。如果發(fa)生(sheng)時(shi)間短,基(ji)(ji)底(di)膜可保(bao)持相對完整(zheng),腎臟功(gong)能(neng)可恢(hui)復,但缺血缺氧的(de)時(shi)間過長,腎小(xiao)管及腎小(xiao)球產生(sheng)廣泛(fan)的(de)嚴重(zhong)破壞,則易(yi)發(fa)生(sheng)急性(xing)腎功(gong)能(neng)衰竭。
肺(fei):發(fa)生(sheng)心(xin)臟性猝死后,肺(fei)可發(fa)生(sheng)淤血(xue)(xue)、水腫。顯微鏡下其主要特(te)征是肺(fei)間(jian)質水腫,并(bing)可見微血(xue)(xue)栓(shuan)形(xing)成。長時間(jian)的肺(fei)缺血(xue)(xue)缺氧(yang)容易發(fa)生(sheng)彌漫性血(xue)(xue)管內(nei)凝血(xue)(xue),不僅可通過機械堵塞使肺(fei)部缺血(xue)(xue)缺氧(yang)進(jin)(jin)一步加重,而且還可引(yin)起血(xue)(xue)小板(ban)聚集(ji),釋放(fang)5-HT等物質產(chan)生(sheng)終末氣道痙攣,結果血(xue)(xue)液-氣體交換障礙進(jin)(jin)一步惡化。
(3)與(yu)心臟性猝死發生的相關(guan)因素
自(zi)(zi)主(zhu)神(shen)(shen)經系統在心(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)猝(cu)死的(de)(de)(de)發(fa)生中具(ju)有重要作用。臨(lin)床(chuang)觀察發(fa)現(xian),冠心(xin)(xin)(xin)(xin)病患(huan)者(zhe)的(de)(de)(de)心(xin)(xin)(xin)(xin)臟性(xing)(xing)(xing)(xing)猝(cu)死常(chang)(chang)發(fa)生在凌晨(chen)至午間(jian)這段時間(jian),與(yu)自(zi)(zi)主(zhu)神(shen)(shen)經活(huo)動的(de)(de)(de)晝夜(ye)節律性(xing)(xing)(xing)(xing)變化(hua)相一致。此時間(jian)段,交感(gan)神(shen)(shen)經活(huo)動較高,血(xue)(xue)壓(ya)與(yu)心(xin)(xin)(xin)(xin)率(lv)增加(jia),血(xue)(xue)小板聚集性(xing)(xing)(xing)(xing)也增加(jia)。實驗研究表明,刺激心(xin)(xin)(xin)(xin)臟的(de)(de)(de)交感(gan)神(shen)(shen)經可降低室(shi)(shi)顫(zhan)閾值,增加(jia)室(shi)(shi)顫(zhan)發(fa)生的(de)(de)(de)危險性(xing)(xing)(xing)(xing);刺激迷走神(shen)(shen)經,可降低室(shi)(shi)顫(zhan)發(fa)生的(de)(de)(de)危險性(xing)(xing)(xing)(xing)。所(suo)以交感(gan)神(shen)(shen)經的(de)(de)(de)過(guo)度興(xing)奮(fen)可促(cu)進惡性(xing)(xing)(xing)(xing)室(shi)(shi)性(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)律失常(chang)(chang)的(de)(de)(de)發(fa)生,而興(xing)奮(fen)迷走神(shen)(shen)經則具(ju)有保(bao)護(hu)心(xin)(xin)(xin)(xin)臟及抗(kang)室(shi)(shi)顫(zhan)的(de)(de)(de)作用。但是,對下后(hou)壁急(ji)性(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)肌(ji)缺(que)血(xue)(xue)或缺(que)血(xue)(xue)性(xing)(xing)(xing)(xing)再灌注的(de)(de)(de)患(huan)者(zhe),因迷走神(shen)(shen)經的(de)(de)(de)傳(chuan)入受體(ti)多數分布在心(xin)(xin)(xin)(xin)室(shi)(shi)的(de)(de)(de)下后(hou)壁,該部位(wei)發(fa)生心(xin)(xin)(xin)(xin)肌(ji)缺(que)血(xue)(xue)或缺(que)血(xue)(xue)后(hou)再灌注,可觸發(fa)Bezold-Jarish反射,導致或加(jia)重緩(huan)慢性(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)律失常(chang)(chang),如嚴重竇性(xing)(xing)(xing)(xing)心(xin)(xin)(xin)(xin)動過(guo)緩(huan),高度房室(shi)(shi)傳(chuan)導阻滯,周圍(wei)血(xue)(xue)管(guan)擴張(zhang)和(he)低血(xue)(xue)壓(ya),嚴重者(zhe)可發(fa)生心(xin)(xin)(xin)(xin)臟驟停。
許多心(xin)臟性猝(cu)死的患(huan)者發(fa)生在睡(shui)眠中。其機制(zhi)主要為(wei)睡(shui)眠時迷走神經興奮,冠狀(zhuang)動脈痙攣,心(xin)臟傳導系統發(fa)生缺氧,心(xin)電不穩定,發(fa)生室(shi)顫而引起心(xin)臟性猝(cu)死。但目前尚(shang)未能提供冠狀(zhuang)動脈痙攣的形態學依據(ju)。
(1)心臟病發(fa)作前,身體(ti)上例如(ru)頸、后(hou)背、頭皮、手(shou)心或(huo)者腳掌都會大量出(chu)汗,此時應(ying)提高警惕,當(dang)心猝死發(fa)生,最好停(ting)止活動休息,及時服用藥(yao)物,必要(yao)時應(ying)立即撥打120。
(2)在無激烈運動、缺(que)少睡眠或者(zhe)生病等誘因的情況(kuang)下,連續(xu)幾天、幾周甚(shen)至幾月(yue)出現極度疲勞感,伴(ban)有(you)焦慮(lv)、失眠、無癥(zheng)(zheng)狀驚醒等癥(zheng)(zheng)狀,此(ci)時應(ying)考慮(lv)心臟出現問(wen)題。
(3)心臟(zang)病(bing)患者經(jing)常(chang)感到肩膀(bang)、頸部、下巴、手臂疼痛(tong),這是心肌(ji)缺(que)血(xue)的信號,因為心肌(ji)缺(que)血(xue)疼痛(tong)在傳遞至大腦中樞神經(jing)時,會(hui)同(tong)(tong)時反(fan)映在水平相同(tong)(tong)的脊髓(sui)段區(qu)域。
(4)心(xin)臟病發作前的(de)典型癥狀是突然、或者無緣由的(de)心(xin)跳(tiao)加劇(ju),一(yi)旦(dan)發生心(xin)室性心(xin)搏過(guo)速,則極有可能在短時間內突然死(si)亡。
(5)很多(duo)心(xin)源性猝死患者在死亡前都反復(fu)出現(xian)(xian)胃腸道癥狀,不少人生前并(bing)沒有胃病病史,這是(shi)心(xin)臟(zang)病發作的信號之一(yi),腸胃不適是(shi)因為心(xin)血(xue)管出現(xian)(xian)異常。動(dong)脈由于脂(zhi)肪沉(chen)積物(wu)堵塞將(jiang)會(hui)減少甚至(zhi)阻(zu)斷血(xue)液傳輸給心(xin)臟(zang),而這會(hui)引起心(xin)絞痛。
心(xin)(xin)臟(zang)(zang)(zang)性猝(cu)死的(de)經(jing)過大體上可(ke)(ke)分為4 個時期(qi)(qi)。即前驅期(qi)(qi),終(zhong)末事件開(kai)始,心(xin)(xin)臟(zang)(zang)(zang)驟(zou)(zou)(zou)停(ting)(ting)(ting)和生(sheng)物學死亡。不同的(de)患者(zhe)各期(qi)(qi)表現(xian)也有(you)明(ming)顯(xian)差異。在發(fa)生(sheng)心(xin)(xin)臟(zang)(zang)(zang)性猝(cu)死的(de)前數(shu)天到(dao)數(shu)月,有(you)些患者(zhe)可(ke)(ke)出現(xian)心(xin)(xin)前區不適(shi)、心(xin)(xin)悸、氣短、乏力(li)等(deng)非(fei)特異性表現(xian)。但亦可(ke)(ke)無(wu)前驅表現(xian),直(zhi)接發(fa)生(sheng)心(xin)(xin)臟(zang)(zang)(zang)驟(zou)(zou)(zou)停(ting)(ting)(ting)。而有(you)些報(bao)道(dao)佩帶動(dong)(dong)態心(xin)(xin)電(dian)圖的(de)猝(cu)死患者(zhe),當(dang)時心(xin)(xin)電(dian)記錄多為心(xin)(xin)室(shi)顫動(dong)(dong),說明(ming)心(xin)(xin)臟(zang)(zang)(zang)驟(zou)(zou)(zou)停(ting)(ting)(ting)時多為心(xin)(xin)室(shi)顫動(dong)(dong)。部分患者(zhe)先有(you)心(xin)(xin)臟(zang)(zang)(zang)缺血(xue)或(huo)左室(shi)功能不全癥狀(zhuang),迅即發(fa)生(sheng)心(xin)(xin)臟(zang)(zang)(zang)驟(zou)(zou)(zou)停(ting)(ting)(ting)。心(xin)(xin)臟(zang)(zang)(zang)驟(zou)(zou)(zou)停(ting)(ting)(ting)前未訴有(you)不適(shi)感覺者(zhe),是否(fou)有(you)無(wu)癥狀(zhuang)心(xin)(xin)肌(ji)缺血(xue)則不能確(que)(que)定。心(xin)(xin)臟(zang)(zang)(zang)驟(zou)(zou)(zou)停(ting)(ting)(ting)后腦血(xue)流銳減,可(ke)(ke)導(dao)致意識突然(ran)喪失(shi)(shi)(shi)。下列體征有(you)助于判斷(duan)(duan)是否(fou)發(fa)生(sheng)心(xin)(xin)臟(zang)(zang)(zang)驟(zou)(zou)(zou)停(ting)(ting)(ting):意識喪失(shi)(shi)(shi),頸、股(gu)動(dong)(dong)脈搏(bo)動(dong)(dong)消失(shi)(shi)(shi),呼吸斷(duan)(duan)續或(huo)停(ting)(ting)(ting)止,皮膚蒼(cang)白或(huo)明(ming)顯(xian)發(fa)紺(gan)。如聽診心(xin)(xin)音(yin)消失(shi)(shi)(shi)更可(ke)(ke)確(que)(que)立(li)診斷(duan)(duan)。經(jing)檢查確(que)(que)立(li)診斷(duan)(duan)后,應立(li)即進行有(you)效的(de)心(xin)(xin)肺復蘇。
(1)心電圖
目前已知,心肌(ji)肥厚是心臟性猝死(si)(si)的(de)(de)標志(zhi)性心電圖(tu)。QRS波群高電壓和(he)側(ce)壁導聯明顯的(de)(de)間(jian)隔部(bu)Q波的(de)(de)出(chu)現(xian)可能(neng)是猝死(si)(si)的(de)(de)危險(xian)因素。大面(mian)積前壁心肌(ji)梗(geng)死(si)(si)的(de)(de)患者,心電圖(tu)出(chu)現(xian)右(you)束支阻滯,6個月的(de)(de)猝死(si)(si)風險(xian)約30%。
(2)動態(tai)心電圖(Holter)
動態(tai)心(xin)(xin)(xin)電(dian)圖可使39%~82%的(de)(de)室(shi)性(xing)(xing)(xing)心(xin)(xin)(xin)律失(shi)常(chang)(chang)患者得到診(zhen)斷(duan),并能了解室(shi)性(xing)(xing)(xing)心(xin)(xin)(xin)律失(shi)常(chang)(chang)的(de)(de)頻(pin)度(du)(du)、復雜程度(du)(du)、晝(zhou)夜節律等變化(hua),尤(you)其是心(xin)(xin)(xin)肌梗死和嚴重的(de)(de)冠心(xin)(xin)(xin)病患者。動態(tai)心(xin)(xin)(xin)電(dian)圖發(fa)現的(de)(de)室(shi)性(xing)(xing)(xing)心(xin)(xin)(xin)律失(shi)常(chang)(chang)對心(xin)(xin)(xin)臟(zang)性(xing)(xing)(xing)猝死的(de)(de)發(fa)生有明(ming)確的(de)(de)預測價值。心(xin)(xin)(xin)臟(zang)性(xing)(xing)(xing)猝死的(de)(de)危險性(xing)(xing)(xing)隨著室(shi)性(xing)(xing)(xing)心(xin)(xin)(xin)律失(shi)常(chang)(chang)的(de)(de)復雜性(xing)(xing)(xing)和頻(pin)發(fa)性(xing)(xing)(xing)而增加(jia)。
(3)運動試驗
有(you)研(yan)究表明,運動試驗(yan)對(dui)心肌梗死后(hou)的(de)患者發(fa)生心臟(zang)性猝死有(you)一定(ding)的(de)預(yu)測價值。
(4)心室晚(wan)電位
(ventricular late potential,VLP) 心(xin)室晚(wan)電(dian)位(wei)(wei)是體表記錄到(dao)的(de)(de)局部(bu)心(xin)室延遲碎裂(lie)(lie)電(dian)活(huo)動,一般出現在QRS終末部(bu)并(bing)可延伸(shen)到(dao)ST內,呈高(gao)頻(20~80Hz)、低幅(fu)(25V=碎裂(lie)(lie)波),持續10s以上。從目前已有的(de)(de)資料來看,心(xin)室晚(wan)電(dian)位(wei)(wei)在預(yu)測患者(zhe)發(fa)生致(zhi)命(ming)性快速性心(xin)律失常方面具(ju)有一定的(de)(de)價值。Brethard等報道,冠心(xin)病患者(zhe)伴有心(xin)室晚(wan)電(dian)位(wei)(wei)陽性者(zhe),發(fa)生心(xin)臟性猝死的(de)(de)危險性比心(xin)室晚(wan)電(dian)位(wei)(wei)陰性者(zhe)高(gao)3.3倍。
臨床上須與(yu)暈厥、癔癥或癲癇相鑒(jian)別。
(1)心(xin)臟性(xing)猝死(si)的(de)緊急治(zhi)療(liao):①心(xin)肺復(fu)蘇(CPR)。早期、有(you)效(xiao)(xiao)的(de)措(cuo)施至關重要(yao)(具體措(cuo)施請參閱心(xin)肺復(fu)蘇)。②進一步的(de)心(xin)臟生命支持(ACLS)。早期除顫對改善(shan)存(cun)活至關重要(yao)。大約40%心(xin)臟性(xing)猝死(si)患(huan)(huan)者(zhe)在(zai)醫務人員到達(da)時發現有(you)心(xin)室(shi)顫動。目前至少有(you)兩(liang)個正在(zai)進行的(de)前瞻性(xing)隨(sui)機臨床實(shi)驗(yan)(yan),研(yan)究胺碘酮在(zai)院外心(xin)臟性(xing)猝死(si)患(huan)(huan)者(zhe)對電擊難治(zhi)性(xing)心(xin)室(shi)顫動中的(de)作用。有(you)一個實(shi)驗(yan)(yan)的(de)初步結果提(ti)示(shi)胺碘酮是這類患(huan)(huan)者(zhe)急診治(zhi)療(liao)的(de)有(you)效(xiao)(xiao)藥物。
(2)心臟性(xing)猝(cu)死的(de)預防性(xing)治療
一級預防治療:
可聯合(he)使用(yong)心臟性猝死(si)的多(duo)種預測(ce)因素。
鑒(jian)于大多(duo)數心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)猝(cu)(cu)死(si)發(fa)生在(zai)冠心(xin)(xin)(xin)(xin)(xin)(xin)(xin)病的(de)患者(zhe),減輕心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)(ji)缺(que)血(xue),預防心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)(ji)梗(geng)死(si)或縮小梗(geng)死(si)范圍,改(gai)變心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)(ji)梗(geng)死(si)后心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室重(zhong)構的(de)藥物應能(neng)減少(shao)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)猝(cu)(cu)死(si)的(de)發(fa)生率。早期研究(jiu)顯示與(yu)藥物治療相(xiang)比(bi),外科血(xue)管(guan)(guan)重(zhong)建,使3支血(xue)管(guan)(guan)病變及左心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室功能(neng)不全(quan)的(de)冠心(xin)(xin)(xin)(xin)(xin)(xin)(xin)病患者(zhe)的(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)猝(cu)(cu)死(si)下降。最近的(de)研究(jiu)顯示,應用溶栓藥和(he)(或)經皮介入治療可(ke)獲得心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)(ji)再灌注和(he)血(xue)管(guan)(guan)重(zhong)建。已有(you)研究(jiu)證實β-阻滯劑(ji)在(zai)預防心(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)(ji)(ji)梗(geng)死(si)存活者(zhe)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)猝(cu)(cu)死(si)及降低其總死(si)亡率方面是有(you)效的(de)。血(xue)管(guan)(guan)緊張(zhang)素(su)轉換酶抑制劑(ji)(ACEI)在(zai)這方面的(de)證據(ju)要少(shao)一些,但有(you)少(shao)數研究(jiu)提示,血(xue)管(guan)(guan)緊張(zhang)素(su)轉換酶抑制劑(ji)(ACEI)使左心(xin)(xin)(xin)(xin)(xin)(xin)(xin)室功能(neng)不全(quan)的(de)患者(zhe)的(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)(zang)性(xing)猝(cu)(cu)死(si)減少(shao)。
已有幾個隨(sui)機(ji)試(shi)驗開始實施,以比(bi)較ICD和藥物對(dui)心(xin)臟性(xing)猝死一(yi)級預(yu)防的(de)效果。在(zai)多中心(xin)自動(dong)心(xin)臟復律除顫器(qi)植入(ru)試(shi)驗(MADIT)中,對(dui)非持續性(xing)室(shi)性(xing)心(xin)動(dong)過(guo)速、心(xin)肌梗死后左(zuo)室(shi)功能(neng)差以及(ji)電生理檢查時可誘發出用普魯(lu)卡因胺不能(neng)抑制的(de)室(shi)性(xing)心(xin)動(dong)過(guo)速患者(zhe),ICD比(bi)常(chang)規抗心(xin)律失常(chang)藥物更(geng)有效。但最近(jin)報(bao)道的(de)冠狀動(dong)脈旁(pang)路移植(CABG)補片(pian)試(shi)驗(patch trail)證明給伴左(zuo)室(shi)功能(neng)不全(quan)和信(xin)號(hao)平(ping)均心(xin)電圖異常(chang)的(de)患者(zhe)做CABG時,預(yu)防性(xing)植入(ru)ICD,并不能(neng)改善存活(huo)。
二級預防治療:
①抗心律失(shi)常藥:
心臟性(xing)(xing)猝死的(de)發生機(ji)制主(zhu)要是(shi)心室(shi)(shi)顫(zhan)動(dong),從理論上講,使用抗(kang)心律失(shi)常藥物(wu)控(kong)制或(huo)消除(chu)各種室(shi)(shi)性(xing)(xing)心律失(shi)常具有防治心臟性(xing)(xing)猝死的(de)作用,但(dan)是(shi),不同抗(kang)心律失(shi)常藥物(wu)的(de)臨床使用結果卻不盡相同。
Ⅰ類抗心(xin)律失常(chang)藥物一度(du)使用十分廣泛(fan),但到(dao)目(mu)前為止,一些大規模隨(sui)機臨床試(shi)驗的結果表明,許多Ⅰ類抗心(xin)律失常(chang)藥物的使用并不能降低心(xin)臟(zang)性猝(cu)死的發(fa)生(sheng)率,相反卻使心(xin)臟(zang)性猝(cu)死的發(fa)生(sheng)率升高,其中,比較(jiao)典型(xing)的是CAST。
CAST即(ji)心(xin)(xin)(xin)律(lv)(lv)失(shi)常(chang)(chang)(chang)(chang)(chang)抑(yi)制實驗(Cardiac arrhythmic suppression trial,CAST),是(shi)(shi)(shi)一項由美國國立心(xin)(xin)(xin)肺血(xue)液(ye)研究組(zu)織的(de)(de)隨機、雙盲(mang)對照(zhao)的(de)(de)多(duo)中心(xin)(xin)(xin)臨床試驗。旨在(zai)確定抗(kang)心(xin)(xin)(xin)律(lv)(lv)失(shi)常(chang)(chang)(chang)(chang)(chang)藥(yao)物(wu)(wu)抑(yi)制心(xin)(xin)(xin)肌梗死(si)后無癥狀(zhuang)或伴有輕度癥狀(zhuang)的(de)(de)室性(xing)心(xin)(xin)(xin)律(lv)(lv)失(shi)常(chang)(chang)(chang)(chang)(chang),并了解(jie)能(neng)否(fou)降(jiang)(jiang)低心(xin)(xin)(xin)律(lv)(lv)失(shi)常(chang)(chang)(chang)(chang)(chang)所致的(de)(de)病死(si)率。1989年(nian)報道的(de)(de)CASTⅠ結果(guo)發(fa)表在(zai)《新(xin)英格蘭(lan)醫院學雜(za)志》第321卷(juan)上。這些研究結果(guo)表明,Ⅰc類(lei)抗(kang)心(xin)(xin)(xin)律(lv)(lv)失(shi)常(chang)(chang)(chang)(chang)(chang)藥(yao)物(wu)(wu)不僅(jin)不能(neng)降(jiang)(jiang)低心(xin)(xin)(xin)肌梗死(si)后心(xin)(xin)(xin)律(lv)(lv)失(shi)常(chang)(chang)(chang)(chang)(chang)的(de)(de)發(fa)生(sheng)率,相反卻可使患者(zhe)的(de)(de)心(xin)(xin)(xin)臟猝死(si)率增加。其原(yuan)因可能(neng)與下列2個(ge)因素有關,一是(shi)(shi)(shi)Ⅰ類(lei)抗(kang)心(xin)(xin)(xin)律(lv)(lv)失(shi)常(chang)(chang)(chang)(chang)(chang)藥(yao)物(wu)(wu)本(ben)身(shen)具(ju)有促心(xin)(xin)(xin)律(lv)(lv)失(shi)常(chang)(chang)(chang)(chang)(chang)作用;二是(shi)(shi)(shi)Ⅰc類(lei)抗(kang)心(xin)(xin)(xin)律(lv)(lv)失(shi)常(chang)(chang)(chang)(chang)(chang)藥(yao)物(wu)(wu)具(ju)有不同程度的(de)(de)心(xin)(xin)(xin)肌抑(yi)制作用,可使患者(zhe)的(de)(de)心(xin)(xin)(xin)功能(neng)進(jin)一步減(jian)退,射血(xue)分數(shu)進(jin)一步降(jiang)(jiang)低。但是(shi)(shi)(shi),CAST僅(jin)僅(jin)是(shi)(shi)(shi)在(zai)心(xin)(xin)(xin)肌梗死(si)后的(de)(de)室性(xing)心(xin)(xin)(xin)律(lv)(lv)失(shi)常(chang)(chang)(chang)(chang)(chang)患者(zhe)中進(jin)行的(de)(de),在(zai)非心(xin)(xin)(xin)律(lv)(lv)失(shi)常(chang)(chang)(chang)(chang)(chang)的(de)(de)患者(zhe)發(fa)生(sheng)的(de)(de)室性(xing)心(xin)(xin)(xin)律(lv)(lv)失(shi)常(chang)(chang)(chang)(chang)(chang)中,Ⅰc類(lei)抗(kang)心(xin)(xin)(xin)律(lv)(lv)失(shi)常(chang)(chang)(chang)(chang)(chang)藥(yao)物(wu)(wu)能(neng)否(fou)降(jiang)(jiang)低心(xin)(xin)(xin)臟性(xing)猝死(si)的(de)(de)發(fa)生(sheng)率,目(mu)前尚不清楚(chu)。
在(zai)(zai)抗(kang)(kang)(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)物(wu)中,目前(qian)Ⅲ類(lei)抗(kang)(kang)(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)物(wu)是(shi)(shi)最(zui)受(shou)推崇(chong)的(de)(de)(de)(de),其(qi)(qi)(qi)(qi)原(yuan)因是(shi)(shi)這(zhe)些藥(yao)物(wu)不僅能(neng)(neng)有(you)效控(kong)制各種室(shi)(shi)性(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang),而(er)且一些多中心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)隨(sui)(sui)機(ji)(ji)臨(lin)床試(shi)(shi)驗(yan)結(jie)(jie)果(guo)表明胺(an)(an)(an)碘(dian)(dian)(dian)酮(tong)(tong),長期(qi)(qi)口服(fu)時(shi)能(neng)(neng)增(zeng)加各種心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)組(zu)(zu)(zu)織的(de)(de)(de)(de)動(dong)作(zuo)電(dian)位時(shi)程和(he)(he)有(you)效不應期(qi)(qi),對各種室(shi)(shi)上(shang)性(xing)(xing)和(he)(he)室(shi)(shi)性(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang),包括心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)房(fang)顫動(dong)、心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)房(fang)撲動(dong)和(he)(he)室(shi)(shi)上(shang)性(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)過(guo)速(su)等都有(you)較好(hao)的(de)(de)(de)(de)效果(guo)。口服(fu)劑(ji)量為(wei)200~800mg/d,,胺(an)(an)(an)碘(dian)(dian)(dian)酮(tong)(tong)除(chu)了Ⅲ類(lei)抗(kang)(kang)(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)物(wu)的(de)(de)(de)(de)特性(xing)(xing)外(wai)(wai),還(huan)有(you)Ⅰ類(lei)抗(kang)(kang)(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)物(wu)作(zuo)用(yong)(yong)(yong)(yong),表現(xian)為(wei)使用(yong)(yong)(yong)(yong)依賴性(xing)(xing)動(dong)力學(xue)(xue)特征,并具有(you)一定的(de)(de)(de)(de)阻(zu)滯作(zuo)用(yong)(yong)(yong)(yong)和(he)(he)鈣通道阻(zu)滯作(zuo)用(yong)(yong)(yong)(yong),其(qi)(qi)(qi)(qi)主要代謝(xie)產物(wu)脫乙(yi)基胺(an)(an)(an)腆(tian)酮(tong)(tong)仍具有(you)抗(kang)(kang)(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang)作(zuo)用(yong)(yong)(yong)(yong)。胺(an)(an)(an)腆(tian)酮(tong)(tong)和(he)(he)Ⅰc類(lei)抗(kang)(kang)(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)物(wu)不同,除(chu)了發揮抗(kang)(kang)(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang)作(zuo)用(yong)(yong)(yong)(yong)之外(wai)(wai),還(huan)有(you)冠狀動(dong)脈(mo)擴張(zhang)作(zuo)用(yong)(yong)(yong)(yong)、抗(kang)(kang)(kang)交感(gan)神經的(de)(de)(de)(de)激活作(zuo)用(yong)(yong)(yong)(yong)和(he)(he)抗(kang)(kang)(kang)甲狀腺(xian)作(zuo)用(yong)(yong)(yong)(yong)。近(jin)年(nian)來,一些研究發現(xian)胺(an)(an)(an)碘(dian)(dian)(dian)酮(tong)(tong)還(huan)有(you)抗(kang)(kang)(kang)氧化(hua)作(zuo)用(yong)(yong)(yong)(yong)和(he)(he)拮(jie)抗(kang)(kang)(kang)鈣調節蛋白(bai)的(de)(de)(de)(de)作(zuo)用(yong)(yong)(yong)(yong)。在(zai)(zai)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)缺血時(shi),胺(an)(an)(an)腆(tian)酮(tong)(tong)能(neng)(neng)保(bao)護線粒體的(de)(de)(de)(de)完整性(xing)(xing)和(he)(he)高能(neng)(neng)磷(lin)酸鹽的(de)(de)(de)(de)功能(neng)(neng)。因此,從(cong)理(li)論上(shang)講,胺(an)(an)(an)碘(dian)(dian)(dian)酮(tong)(tong)在(zai)(zai)室(shi)(shi)性(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang)的(de)(de)(de)(de)防治(zhi)(zhi)(zhi)中具有(you)自己(ji)獨特的(de)(de)(de)(de)治(zhi)(zhi)(zhi)療(liao)(liao)(liao)價(jia)值。“巴塞(sai)爾心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)梗(geng)幸(xing)存(cun)者(zhe)的(de)(de)(de)(de)抗(kang)(kang)(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang)研究(Basel antiarrhythmic study of infarction survival,BASIS)”在(zai)(zai)臨(lin)床實踐中提示胺(an)(an)(an)碘(dian)(dian)(dian)酮(tong)(tong)在(zai)(zai)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)性(xing)(xing)猝死(si)(si)防治(zhi)(zhi)(zhi)中的(de)(de)(de)(de)價(jia)值。BASIS由瑞士(shi)學(xue)(xue)者(zhe)完成,入選病例為(wei)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)梗(geng)死(si)(si)后(hou)(hou)(hou)(hou)8~24天(tian)并伴有(you)室(shi)(shi)性(xing)(xing)期(qi)(qi)前(qian)收(shou)縮(suo)在(zai)(zai)Lown氏分(fen)級4~6級的(de)(de)(de)(de)患(huan)者(zhe)。321例患(huan)者(zhe)被隨(sui)(sui)機(ji)(ji)分(fen)為(wei)2組(zu)(zu)(zu),分(fen)別用(yong)(yong)(yong)(yong)安(an)(an)(an)慰劑(ji)、胺(an)(an)(an)碘(dian)(dian)(dian)酮(tong)(tong)和(he)(he)其(qi)(qi)(qi)(qi)他抗(kang)(kang)(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)物(wu)治(zhi)(zhi)(zhi)療(liao)(liao)(liao),結(jie)(jie)果(guo)胺(an)(an)(an)腆(tian)酮(tong)(tong)治(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)的(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)性(xing)(xing)猝死(si)(si)率(lv)(lv)為(wei)5%,顯著低于安(an)(an)(an)慰劑(ji)治(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)的(de)(de)(de)(de)11.4%t和(he)(he)其(qi)(qi)(qi)(qi)他抗(kang)(kang)(kang)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang)藥(yao)物(wu)治(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)的(de)(de)(de)(de)9%。此外(wai)(wai),另外(wai)(wai)兩(liang)項(xiang)大規模隨(sui)(sui)機(ji)(ji)臨(lin)床試(shi)(shi)驗(yan)“加拿大胺(an)(an)(an)碘(dian)(dian)(dian)酮(tong)(tong)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)梗(geng)死(si)(si)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang)試(shi)(shi)驗(yan)(Canadian amiodarone myocardial infarction arrhythmia trial,CAMIAT)”和(he)(he)歐洲心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)梗(geng)死(si)(si)胺(an)(an)(an)碘(dian)(dian)(dian)酮(tong)(tong)試(shi)(shi)驗(yan)“European myocardial infarction amiodarone trial,EMIAT)”正(zheng)在(zai)(zai)進行,最(zui)后(hou)(hou)(hou)(hou)結(jie)(jie)果(guo)尚(shang)未(wei)揭曉。CAMLAT有(you)21個醫(yi)學(xue)(xue)中心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)參加,計劃入選心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)梗(geng)死(si)(si)后(hou)(hou)(hou)(hou)6~45天(tian)伴室(shi)(shi)性(xing)(xing)期(qi)(qi)前(qian)收(shou)縮(suo)10次/h以上(shang)或室(shi)(shi)性(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)動(dong)過(guo)速(su)1次以上(shang)的(de)(de)(de)(de)患(huan)者(zhe),隨(sui)(sui)機(ji)(ji)分(fen)為(wei)胺(an)(an)(an)碘(dian)(dian)(dian)酮(tong)(tong)治(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)和(he)(he)安(an)(an)(an)慰劑(ji)治(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu),預試(shi)(shi)完成77例,20個月的(de)(de)(de)(de)觀(guan)察表明,胺(an)(an)(an)碘(dian)(dian)(dian)酮(tong)(tong)治(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)的(de)(de)(de)(de)病死(si)(si)率(lv)(lv)4%而(er)安(an)(an)(an)慰劑(ji)治(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)的(de)(de)(de)(de)病死(si)(si)率(lv)(lv)14%。EMIAT由61個醫(yi)學(xue)(xue)中心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)參加,計劃入選心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)梗(geng)死(si)(si)后(hou)(hou)(hou)(hou)5~21天(tian)、左心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)室(shi)(shi)射血分(fen)數在(zai)(zai)40%以下的(de)(de)(de)(de)室(shi)(shi)性(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang)患(huan)者(zhe),隨(sui)(sui)機(ji)(ji)分(fen)為(wei)安(an)(an)(an)慰劑(ji)治(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)和(he)(he)胺(an)(an)(an)碘(dian)(dian)(dian)酮(tong)(tong)治(zhi)(zhi)(zhi)療(liao)(liao)(liao)組(zu)(zu)(zu)。中期(qi)(qi)結(jie)(jie)果(guo)表明,胺(an)(an)(an)腆(tian)酮(tong)(tong)可顯著降低心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)肌(ji)梗(geng)死(si)(si)后(hou)(hou)(hou)(hou)室(shi)(shi)性(xing)(xing)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)律(lv)(lv)失(shi)(shi)常(chang)(chang)(chang)(chang)患(huan)者(zhe)的(de)(de)(de)(de)心(xin)(xin)(xin)(xin)(xin)(xin)(xin)(xin)臟(zang)(zang)性(xing)(xing)猝死(si)(si)率(lv)(lv)。
索他洛爾(sotalol)與胺碘酮相似,也(ye)具有混(hun)合性抗心律失(shi)常作用。許多學者的臨(lin)床(chuang)(chuang)觀察表明,索他洛爾對心律失(shi)常患者的生(sheng)存有益,但還缺乏長期多中心臨(lin)床(chuang)(chuang)試驗的結果。
②β-腎(shen)上(shang)腺(xian)素受(shou)體阻(zu)滯(zhi)藥:β-腎(shen)上(shang)腺(xian)能(neng)受(shou)體阻(zu)滯(zhi)藥的(de)(de)作用在于競(jing)爭心臟,血(xue)管和支氣(qi)管等組織器官β腎(shen)上(shang)的(de)(de)腺(xian)素能(neng)受(shou)體,使受(shou)體不能(neng)恢復到(dao)高親(qin)和力狀態而(er)與激動(dong)劑結合,從而(er)抑制β腎(shen)上(shang)腺(xian)素能(neng)受(shou)體的(de)(de)活性而(er)發(fa)揮一系(xi)列的(de)(de)藥理作用。
β受體阻滯藥在心臟性猝死中的(de)應用(yong)價(jia)值仍有(you)爭議,但(dan)多數(shu)學者認為在一(yi)些心臟的(de)某一(yi)亞組可使心臟性猝死的(de)發(fa)生率(lv)降(jiang)低。
到(dao)目前為止,已(yi)有大量(liang)的(de)(de)(de)研(yan)究提示(shi),心(xin)(xin)肌(ji)梗(geng)死(si)(si)后的(de)(de)(de)患者(zhe)(zhe)接受(shou)(shou)β受(shou)(shou)體(ti)阻滯(zhi)劑治療非常有益,特別是(shi)在(zai)降(jiang)低心(xin)(xin)臟(zang)性猝死(si)(si)方(fang)面有較顯著的(de)(de)(de)意義,并(bing)且還有人發(fa)(fa)(fa)現,在(zai)一定范圍內心(xin)(xin)率降(jiang)得(de)越慢效(xiao)果越明顯。已(yi)有2項多中心(xin)(xin)隨機(ji)臨床試驗(yan)-(MIAMI)和(he)(ISIS-I)觀察了β受(shou)(shou)體(ti)阻滯(zhi)劑在(zai)胸(xiong)痛(tong)發(fa)(fa)(fa)作12~24h內早期干預的(de)(de)(de)作用(yong)(yong)。MIAMI入(ru)選胸(xiong)痛(tong)發(fa)(fa)(fa)作24h以內的(de)(de)(de)心(xin)(xin)肌(ji)梗(geng)死(si)(si)患者(zhe)(zhe)5778例,首先使用(yong)(yong)美托洛爾(er)15mg靜脈注(zhu)射,然后200mg/d口服,1周病死(si)(si)率下降(jiang)13%。ISIS-I入(ru)選胸(xiong)痛(tong)發(fa)(fa)(fa)作12h內的(de)(de)(de)心(xin)(xin)肌(ji)梗(geng)死(si)(si)患者(zhe)(zhe)16000例,首先靜脈注(zhu)射阿替洛爾(er)5~10mg,然后每(mei)周口服100mg,1周內心(xin)(xin)血(xue)管病死(si)(si)率下降(jiang)15%。β-受(shou)(shou)體(ti)阻滯(zhi)藥的(de)(de)(de)作用(yong)(yong)主要是(shi)降(jiang)低了心(xin)(xin)室顫動或心(xin)(xin)臟(zang)破裂的(de)(de)(de)發(fa)(fa)(fa)生(sheng)率。在(zai)心(xin)(xin)肌(ji)梗(geng)死(si)(si)的(de)(de)(de)后期,使用(yong)(yong)β-受(shou)(shou)體(ti)阻滯(zhi)藥可(ke)使心(xin)(xin)血(xue)管總病死(si)(si)率降(jiang)低20%~25%,但對心(xin)(xin)臟(zang)性猝死(si)(si)發(fa)(fa)(fa)生(sheng)率的(de)(de)(de)影響尚(shang)不(bu)清(qing)楚。
在高血(xue)(xue)(xue)壓患者(zhe)中,β-受體(ti)(ti)阻(zu)滯藥(yao)治(zhi)療也對心(xin)臟性(xing)猝(cu)(cu)死具有(you)防治(zhi)作用。但更多(duo)的(de)學者(zhe)認為,只有(you)脂溶(rong)性(xing)的(de)β-受體(ti)(ti)阻(zu)滯藥(yao)如美(mei)托(tuo)洛(luo)爾才能有(you)效地(di)降低心(xin)臟性(xing)猝(cu)(cu)死的(de)發生率。脂溶(rong)性(xing)β-受體(ti)(ti)阻(zu)滯藥(yao)在消化(hua)道易于(yu)吸收,易于(yu)通(tong)過(guo)血(xue)(xue)(xue)腦屏障,在中樞神經(jing)系統(tong)可(ke)以達到(dao)較高的(de)血(xue)(xue)(xue)藥(yao)濃度。一些小樣本研究提(ti)示,選擇性(xing)β-受體(ti)(ti)阻(zu)滯藥(yao)美(mei)托(tuo)洛(luo)爾和阿替(ti)爾對心(xin)臟性(xing)猝(cu)(cu)死的(de)防治(zhi)有(you)效。
③正性肌力藥物:
在充(chong)血(xue)性(xing)心(xin)力(li)衰(shuai)竭患者中(zhong)(zhong),心(xin)臟性(xing)猝(cu)(cu)死的(de)(de)(de)發生(sheng)很高。1993年,Goldman等報道,冠(guan)心(xin)病(bing)引(yin)起的(de)(de)(de)充(chong)血(xue)性(xing)心(xin)力(li)衰(shuai)竭患者中(zhong)(zhong)44%死于心(xin)臟性(xing)猝(cu)(cu)死;非冠(guan)心(xin)病(bing)引(yin)起的(de)(de)(de)充(chong)血(xue)性(xing)心(xin)力(li)衰(shuai)竭患者中(zhong)(zhong),心(xin)臟性(xing)猝(cu)(cu)死的(de)(de)(de)發生(sheng)率(lv)為48%。因此,正性(xing)肌力(li)藥物在心(xin)臟性(xing)猝(cu)(cu)死防治中(zhong)(zhong)的(de)(de)(de)價(jia)值受到人們的(de)(de)(de)關注。
正性肌力藥(yao)物(wu)主要(yao)包括兩類(lei),即洋地黃類(lei)藥(yao)物(wu)和cAMP依(yi)賴性強心劑(ji)。
洋地(di)黃類藥(yao)物(wu)仍是目前治(zhi)療心(xin)力(li)衰(shuai)(shuai)竭的(de)基本藥(yao)物(wu)。近年來的(de)研究(jiu)表明(ming),洋地(di)黃類藥(yao)物(wu)不僅能增強心(xin)肌收縮力(li)、減慢心(xin)率(lv)和傳(chuan)導(dao),而(er)且(qie)具(ju)有神(shen)經(jing)內(nei)分(fen)泌調節作用,可(ke)改(gai)善(shan)心(xin)力(li)衰(shuai)(shuai)竭患者的(de)壓力(li)感受器功(gong)能低(di)下和交感神(shen)經(jing)系統、腎素-血(xue)管緊張素-醛固(gu)酮(tong)系統的(de)功(gong)能亢進,并可(ke)提高心(xin)鈉素的(de)分(fen)泌,降(jiang)低(di)心(xin)臟(zang)前負(fu)荷。盡管洋地(di)黃的(de)應用已有200多年的(de)歷史,但他在充血(xue)性心(xin)力(li)衰(shuai)(shuai)竭治(zhi)療中是否能降(jiang)低(di)心(xin)臟(zang)性猝死的(de)發(fa)生率(lv)仍不十分(fen)清楚。1998年以(yi)來,已有幾項大規模隨機臨床(chuang)試(shi)驗(yan)結果可(ke)直接或間接反映地(di)高辛(xin)治(zhi)療心(xin)力(li)衰(shuai)(shuai)竭是有效的(de),不僅能改(gai)善(shan)充血(xue)性心(xin)力(li)衰(shuai)(shuai)竭的(de)癥狀,而(er)且(qie)可(ke)以(yi)提高患者的(de)運(yun)動量和心(xin)功(gong)能,但均未(wei)闡明(ming)地(di)高辛(xin)對心(xin)臟(zang)性猝死的(de)防治(zhi)作用。
CAMP依(yi)賴性強心(xin)劑(ji)(ji)包(bao)括:受體激動劑(ji)(ji)和(he)磷酸(suan)二酯酶Ⅲ抑制劑(ji)(ji)。前者(zhe)(zhe)主要多巴酚(fen)丁(ding)胺、沙丁(ding)胺醇等;后(hou)者(zhe)(zhe)包(bao)括氨(an)力(li)農(nong)。米力(li)農(nong)。臨(lin)床實(shi)踐的(de)結果表明(ming),cAMP依(yi)賴性強心(xin)劑(ji)(ji)在增強心(xin)肌收縮力(li)和(he)改善患者(zhe)(zhe)的(de)癥狀方面(mian)具有一(yi)度的(de)療效,但口(kou)服給藥的(de)不良反應(ying)較多,而且可增加心(xin)臟性猝死(si)的(de)發生率。因此(ci),氨(an)力(li)農(nong)和(he)米力(li)農(nong)等藥物的(de)口(kou)服給藥已經禁止(zhi)采用。
④抗血小板藥:
A.臨床常用(yong)的抗(kang)血小板藥物及其作用(yong)原理(li):
抗血小(xiao)板(ban)藥物是指能阻礙血小(xiao)板(ban)黏附(fu)、聚(ju)集(ji)和釋放反應,以防止(zhi)血栓形成的藥物。根據作用的環節,常(chang)用的抗血小(xiao)板(ban)藥物包括以下幾類:
a.環氧(yang)化酶(mei)抑制藥:
包括阿(a)司(si)匹林(aspirin)、磺吡(bi)酮(tong)(苯磺唑酮(tong))等(deng)。阿(a)司(si)匹林是一(yi)種非甾體抗(kang)(kang)炎(yan)藥,1971年發現它有抑制環氧(yang)化酶的(de)作用(yong),目前已(yi)成為最常用(yong)的(de)抗(kang)(kang)血小板藥物。
花生(sheng)四(si)烯酸在(zai)(zai)環(huan)氧(yang)化酶(即(ji)前列(lie)腺素(su)合成(cheng)酶)的(de)(de)作用下(xia)形成(cheng)不穩(wen)定(ding)的(de)(de)環(huan)內過(guo)氧(yang)化物,即(ji)前列(lie)腺素(su)C2(PGG2)和前列(lie)腺素(su)H2(PGH2)。環(huan)內過(guo)氧(yang)化物在(zai)(zai)血(xue)(xue)小(xiao)板(ban)(ban)微(wei)(wei)粒體中血(xue)(xue)栓烷合酶的(de)(de)作用下(xia)生(sheng)成(cheng)血(xue)(xue)栓素(su)A2(TXA2),但TXA2不穩(wen)定(ding),半(ban)衰(shuai)期為(wei)(wei)30s,迅速轉(zhuan)變為(wei)(wei)穩(wen)定(ding)的(de)(de)TXB2。在(zai)(zai)血(xue)(xue)管壁微(wei)(wei)粒體中,環(huan)內過(guo)氧(yang)化物在(zai)(zai)6(9)-環(huan)氧(yang)化酶作用下(xia)合成(cheng)前列(lie)腺素(su)I2(PGl2),然后代謝為(wei)(wei)6-酮(tong)-PGFla。TAX2使(shi)血(xue)(xue)管收縮(suo),降低血(xue)(xue)小(xiao)板(ban)(ban)cAMP,促進(jin)血(xue)(xue)小(xiao)板(ban)(ban)聚集和血(xue)(xue)栓形成(cheng)。
阿司(si)匹(pi)(pi)(pi)林(lin)主要抑(yi)制(zhi)環氧化酶(mei),使其活性基團(tuan)乙酰化,從而(er)阻止TXA2和PGI2的(de)生成。由(you)于(yu)阿司(si)匹(pi)(pi)(pi)林(lin)在抑(yi)制(zhi)TXB2的(de)同時,也對(dui)PGI2造成了抑(yi)制(zhi),則阿司(si)匹(pi)(pi)(pi)林(lin)使用的(de)有益作用被削弱或抵消(xiao)。大量研究(jiu)表(biao)明,75~325mg/d的(de)阿司(si)匹(pi)(pi)(pi)林(lin)給藥對(dui)PGI2的(de)影響較弱或幾(ji)乎沒(mei)有影響,而(er)對(dui)TXB2的(de)仍(reng)有明顯的(de)抑(yi)制(zhi)作用。
磺(huang)吡酮(苯磺(huang)唑酮)是保(bao)太(tai)松(song)類藥(yao)物的(de)衍生物,1950年被用于治療痛風(feng),1965年發現它對血(xue)(xue)小板(ban)(ban)功能具有明顯(xian)影(ying)響。現已(yi)知道(dao),主要(yao)抑制血(xue)(xue)小板(ban)(ban)的(de)環氧化(hua)酶而抑制TXA2的(de)合成(cheng),并可抑制血(xue)(xue)小板(ban)(ban)的(de)聚集和(he)釋(shi)放(fang)反應。對血(xue)(xue)管內皮細(xi)胞(bao)合成(cheng)的(de)PGI2影(ying)響極小。
b.磷(lin)酸二酯酶(mei)抑制(zhi)藥:
包(bao)括雙(shuang)嘧(mi)達(da)莫(mo)(persantine)等(deng)。雙(shuang)嘧(mi)達(da)莫(mo)又(you)叫潘(pan)生(sheng)丁,是一(yi)種(zhong)廣泛應用(yong)于(yu)臨床的(de)抗血小(xiao)板(ban)(ban)(ban)藥物,其(qi)機(ji)制是抑(yi)制血小(xiao)板(ban)(ban)(ban)的(de)磷酸二酯(zhi)酶,使血小(xiao)板(ban)(ban)(ban)的(de)cAMP含量升高。同(tong)時,雙(shuang)嘧(mi)達(da)莫(mo)(潘(pan)生(sheng)丁)還可通過增(zeng)(zeng)加血液的(de)腺(xian)(xian)苷(gan)濃度而抑(yi)制血小(xiao)板(ban)(ban)(ban)的(de)聚(ju)集(ji)和釋放反應。潘(pan)生(sheng)丁可抑(yi)制紅細胞(bao)和心、肺等(deng)組織細胞(bao)對(dui)血中腺(xian)(xian)苷(gan)的(de)攝取(qu)。則腺(xian)(xian)苷(gan)不能(neng)被腺(xian)(xian)苷(gan)脫胺(an)酶所破壞,血液中腺(xian)(xian)苷(gan)水(shui)平增(zeng)(zeng)加,一(yi)般口服給藥,每次(ci)400mg,1~2次(ci)/d。主要不良反應為胃腸道癥狀。
c.血栓合成酶抑(yi)制藥:
包括水楊酸(suan)咪(mi)唑(咪(mi)唑)、達唑氧(yang)苯(dazoxiben)、對乙酰氨基(ji)酚(APA)等。
d.腺苷酸(suan)環化酶激活劑:
依前(qian)列(lie)醇(chun)(前(qian)列(lie)腺素I2)和(he)前(qian)列(lie)地爾(前(qian)列(lie)腺素E1) 等。
e.其他:
噻氯匹定(ding)(噻氯吡啶)、舒洛地爾(suloctidil)等。
B.抗血小(xiao)板(ban)藥物防(fang)治心臟性(xing)猝死(si)的價(jia)值:
在(zai)抗(kang)血小板(ban)藥(yao)物(wu)的(de)(de)(de)研(yan)究(jiu)中,較多(duo)(duo)的(de)(de)(de)資料為阿(a)(a)(a)(a)(a)司匹(pi)林(lin)(lin)。許多(duo)(duo)研(yan)究(jiu)表(biao)明(ming),阿(a)(a)(a)(a)(a)司匹(pi)林(lin)(lin)在(zai)穩定(ding)性(xing)和不穩定(ding)性(xing)心(xin)絞痛(tong)患者(zhe)(zhe)中的(de)(de)(de)應用(yong)(yong)后(hou),可(ke)顯著降(jiang)低致(zhi)死(si)(si)(si)(si)(si)性(xing)和非致(zhi)死(si)(si)(si)(si)(si)性(xing)心(xin)肌(ji)(ji)梗(geng)死(si)(si)(si)(si)(si)的(de)(de)(de)發(fa)(fa)生(sheng)率(lv)(lv);在(zai)心(xin)肌(ji)(ji)梗(geng)死(si)(si)(si)(si)(si)患者(zhe)(zhe)應用(yong)(yong)后(hou),可(ke)顯著降(jiang)低再(zai)梗(geng)死(si)(si)(si)(si)(si)的(de)(de)(de)發(fa)(fa)生(sheng)率(lv)(lv)。但是,有關阿(a)(a)(a)(a)(a)司匹(pi)林(lin)(lin)防治(zhi)心(xin)臟(zang)(zang)病猝死(si)(si)(si)(si)(si)的(de)(de)(de)價值,不同學者(zhe)(zhe)的(de)(de)(de)報道不盡一致(zhi)。德國-奧地(di)利多(duo)(duo)中心(xin)研(yan)究(jiu)結果(guo)提示(shi),阿(a)(a)(a)(a)(a)司匹(pi)林(lin)(lin)對心(xin)臟(zang)(zang)性(xing)猝死(si)(si)(si)(si)(si)的(de)(de)(de)防治(zhi)有一定(ding)作(zuo)用(yong)(yong)。Elwood等報道用(yong)(yong)阿(a)(a)(a)(a)(a)司匹(pi)林(lin)(lin)治(zhi)療心(xin)肌(ji)(ji)梗(geng)死(si)(si)(si)(si)(si)進行隨機(ji)、雙盲大宗(zong)病例研(yan)究(jiu)的(de)(de)(de)結果(guo),發(fa)(fa)現在(zai)心(xin)肌(ji)(ji)梗(geng)死(si)(si)(si)(si)(si)后(hou)6周以(yi)內使用(yong)(yong)阿(a)(a)(a)(a)(a)司匹(pi)林(lin)(lin)者(zhe)(zhe),33個月隨訪期間(jian)的(de)(de)(de)心(xin)臟(zang)(zang)性(xing)猝死(si)(si)(si)(si)(si)率(lv)(lv)在(zai)阿(a)(a)(a)(a)(a)司匹(pi)林(lin)(lin)組為7.8%、安慰劑組為13.5%,阿(a)(a)(a)(a)(a)司匹(pi)林(lin)(lin)組心(xin)臟(zang)(zang)性(xing)猝死(si)(si)(si)(si)(si)的(de)(de)(de)發(fa)(fa)生(sheng)率(lv)(lv)降(jiang)低了42%。如果(guo)阿(a)(a)(a)(a)(a)司匹(pi)林(lin)(lin)的(de)(de)(de)使用(yong)(yong)時間(jian)較晚則(ze)對心(xin)臟(zang)(zang)性(xing)猝死(si)(si)(si)(si)(si)的(de)(de)(de)發(fa)(fa)生(sheng)率(lv)(lv)無明(ming)顯作(zuo)用(yong)(yong)。
雙(shuang)(shuang)(shuang)嘧(mi)達莫(潘(pan)(pan)生(sheng)丁(ding))在心(xin)臟性(xing)猝死防治中的評價研究(jiu)多為(wei)與阿(a)司(si)匹(pi)林聯合應用。雙(shuang)(shuang)(shuang)嘧(mi)達莫(潘(pan)(pan)生(sheng)丁(ding))和阿(a)司(si)匹(pi)林的再梗死研究(jiu)(PARIS)的結(jie)果提示,雙(shuang)(shuang)(shuang)嘧(mi)達莫(潘(pan)(pan)生(sheng)丁(ding))和阿(a)司(si)匹(pi)林合用可降低心(xin)肌(ji)梗死后的總病死率和心(xin)臟性(xing)猝死發(fa)生(sheng)率。
磺(huang)吡(bi)酮(tong)(苯磺(huang)唑酮(tong))在(zai)心臟性(xing)猝(cu)死防治(zhi)中的(de)價值(zhi)研究不(bu)多(duo)。美(mei)國(guo)磺(huang)吡(bi)酮(tong)(苯磺(huang)唑酮(tong))研究組(zu)報道,在(zai)6個月(yue)內,磺(huang)吡(bi)酮(tong)(苯磺(huang)唑酮(tong))可顯(xian)著(zhu)降(jiang)低心臟性(xing)猝(cu)死的(de)發生率;而在(zai)6個月(yue)后對心臟性(xing)猝(cu)死的(de)發生率無明顯(xian)影響。
⑤血管緊張素轉換酶抑制藥:
血管緊張素轉換酶抑制藥(yao)(angiotensin converting enzyme inhibitor,ACEI)是目前(qian)世(shi)界上發(fa)展最快的一(yi)類(lei)心(xin)血管藥(yao)物(wu),目前(qian)在(zai)臨(lin)床上得到(dao)廣泛應用(yong),許多研究(jiu)發(fa)現(xian),ACEI對心(xin)肌梗死(si)、高血壓和充血性(xing)心(xin)力衰竭等(deng)疾病可能并發(fa)的心(xin)臟性(xing)猝死(si)具有(you)一(yi)定的防(fang)治作用(yong)。
目前(qian)(qian),ACEI已發展到幾十種(zhong)。根據其(qi)含有的(de)(de)基(ji)(ji)團(tuan)不(bu)同,ACEI可分(fen)為(wei)3種(zhong)類(lei)型:A.含巰基(ji)(ji)的(de)(de)ACEI。主要有卡托普(pu)(pu)(pu)(pu)利(li)(captopril);B.含羥基(ji)(ji)的(de)(de)ACEI。主要有依那普(pu)(pu)(pu)(pu)利(li)(enalapril)、雷米普(pu)(pu)(pu)(pu)利(li)(ramipril)、貝那普(pu)(pu)(pu)(pu)利(li)(苯拉普(pu)(pu)(pu)(pu)利(li))等。C.含磷(lin)酰基(ji)(ji)的(de)(de)ACEI。主要有福辛普(pu)(pu)(pu)(pu)利(li)(fosinopril)等。其(qi)基(ji)(ji)本作(zuo)用(yong)機制是抑(yi)制血管(guan)緊(jin)(jin)(jin)張(zhang)(zhang)素(su)轉(zhuan)(zhuan)換酶(mei)(mei)(mei),血管(guan)緊(jin)(jin)(jin)張(zhang)(zhang)素(su)轉(zhuan)(zhuan)換酶(mei)(mei)(mei)是一種(zhong)含有鋅(xin)離(li)子(zi)的(de)(de)金屬蛋白,各個活性部位都含有鋅(xin)離(li)子(zi),ACEI的(de)(de)巰基(ji)(ji)、羥基(ji)(ji)或磷(lin)酰基(ji)(ji)可與鋅(xin)離(li)子(zi)發生牢固(gu)的(de)(de)絡合(he)作(zuo)用(yong)而使血管(guan)緊(jin)(jin)(jin)張(zhang)(zhang)素(su)轉(zhuan)(zhuan)換酶(mei)(mei)(mei)失(shi)去活性。結果血管(guan)緊(jin)(jin)(jin)張(zhang)(zhang)素(su)Ⅰ不(bu)能(neng)轉(zhuan)(zhuan)變為(wei)血管(guan)緊(jin)(jin)(jin)張(zhang)(zhang)素(su)Ⅱ,可導(dao)致血管(guan)擴張(zhang)(zhang)、醛固(gu)酮分(fen)泌減(jian)(jian)少(shao)和(he)(he)交(jiao)感神經張(zhang)(zhang)力降低。此外(wai),ACEI還可抑(yi)制激(ji)肽酶(mei)(mei)(mei),減(jian)(jian)慢緩激(ji)肽的(de)(de)降解,引起(qi)血管(guan)擴張(zhang)(zhang);同時,緩激(ji)肽的(de)(de)濃度(du)增(zeng)高可激(ji)活前(qian)(qian)磷(lin)脂酶(mei)(mei)(mei)而使前(qian)(qian)列腺素(su)的(de)(de)生成增(zeng)加(jia)。ACEI還可減(jian)(jian)少(shao)鈣離(li)子(zi)內流(liu),使心肌(ji)細(xi)胞內鈣離(li)子(zi)超負荷(he)而引起(qi)的(de)(de)心律失(shi)常減(jian)(jian)少(shao)。這些作(zuo)用(yong)對于冠心病、高血壓病和(he)(he)充血性心力衰(shuai)竭(jie)等具有治療(liao)價值,還可增(zeng)加(jia)心肌(ji)細(xi)胞電活動的(de)(de)穩定性。
⑥代謝類藥物:
曲(qu)美他(ta)嗪(萬(wan)爽力(li)),抑制(zhi)心(xin)肌(ji)(ji)細(xi)胞(bao)線粒體內脂肪酸的氧化,加速糖原酵(jiao)解,增(zeng)加心(xin)肌(ji)(ji)細(xi)胞(bao)無氧代謝下ATP的產生(sheng),增(zeng)強心(xin)肌(ji)(ji)細(xi)胞(bao)的抗缺血能力(li),從(cong)而可(ke)預防(fang)心(xin)臟性猝死的發(fa)生(sheng)。
埋(mai)藏式(shi)自(zi)動(dong)心(xin)臟(zang)復律除顫(zhan)器(ICD)的應用(yong)是防(fang)(fang)治(zhi)心(xin)臟(zang)性(xing)猝死(si)的重要進展(zhan),對(dui)致命性(xing)室性(xing)心(xin)律失常引起的心(xin)臟(zang)性(xing)猝死(si)具有肯(ken)定的防(fang)(fang)治(zhi)作用(yong)。
植入ICD的(de)臨床價值(zhi)在(zai)于有效(xiao)地防治(zhi)心(xin)臟(zang)猝死(si)。據文(wen)獻報道,美國(guo)每年(nian)因心(xin)臟(zang)驟(zou)(zou)停(ting)而發(fa)生心(xin)臟(zang)性猝死(si)的(de)患(huan)者(zhe)(zhe)達50萬人以上,歐洲約40萬人。其中75%~80%的(de)患(huan)者(zhe)(zhe)在(zai)第1次(ci)心(xin)臟(zang)驟(zou)(zou)停(ting)發(fa)作時(shi)死(si)亡(wang),經有效(xiao)心(xin)肺腦復(fu)蘇(su)而幸(xing)存(cun)者(zhe)(zhe)中20%~25%的(de)患(huan)者(zhe)(zhe)可在(zai)1年(nian)內再(zai)次(ci)發(fa)生心(xin)臟(zang)驟(zou)(zou)停(ting),因此,ICD的(de)應用范圍非(fei)常廣泛。
也有(you)一些學(xue)者對(dui)植入(ru)ICD的(de)(de)(de)兩(liang)種不(bu)同(tong)方式進行了對(dui)比(bi),結果發現經靜脈(mo)植入(ru)ICD的(de)(de)(de)圍術期病(bing)死(si)率較低,長期隨訪的(de)(de)(de)存活率高,應列為(wei)首(shou)選方法(fa)。Saksena等總結了221例多中心植入(ru)ICD的(de)(de)(de)結果,開(kai)胸(xiong)法(fa)植入(ru)ICD的(de)(de)(de)圍術期病(bing)死(si)率為(wei)4.2%,經靜脈(mo)法(fa)為(wei)0.8%,隨訪2年的(de)(de)(de)總成活率分別為(wei)81.9%和87.6%,并無顯著性(xing)差(cha)異。
為了明確(que)揭示埋(mai)藏(zang)(zang)式(shi)(shi)心(xin)(xin)(xin)(xin)(xin)臟(zang)復(fu)律(lv)除顫(zhan)器(qi)防治(zhi)心(xin)(xin)(xin)(xin)(xin)臟(zang)猝死(si)的價值,有(you)學(xue)者進行了一(yi)些多中心(xin)(xin)(xin)(xin)(xin)隨(sui)機化前瞻性(xing)對照研(yan)究(jiu)。抗心(xin)(xin)(xin)(xin)(xin)律(lv)失(shi)常(chang)藥(yao)物與埋(mai)藏(zang)(zang)式(shi)(shi)心(xin)(xin)(xin)(xin)(xin)臟(zang)復(fu)律(lv)除顫(zhan)器(qi)對致命性(xing)室(shi)性(xing)心(xin)(xin)(xin)(xin)(xin)律(lv)失(shi)常(chang)復(fu)蘇(su)(su)患者治(zhi)療比較(jiao)研(yan)究(jiu)(AVID)表(biao)明,室(shi)顫(zhan)復(fu)蘇(su)(su)者或有(you)癥狀和血(xue)流(liu)動力學(xue)障礙的持續性(xing)室(shi)性(xing)心(xin)(xin)(xin)(xin)(xin)動過(guo)速患者,應用埋(mai)藏(zang)(zang)式(shi)(shi)心(xin)(xin)(xin)(xin)(xin)臟(zang)復(fu)律(lv)除顫(zhan)器(qi)與抗心(xin)(xin)(xin)(xin)(xin)律(lv)失(shi)常(chang)藥(yao)物相比,可明顯提高生存率。其他一(yi)些多中心(xin)(xin)(xin)(xin)(xin)試驗如多中心(xin)(xin)(xin)(xin)(xin)自動除顫(zhan)器(qi)埋(mai)藏(zang)(zang)試驗(MADIT)、加(jia)拿大埋(mai)藏(zang)(zang)式(shi)(shi)除顫(zhan)器(qi)研(yan)究(jiu)(CIDS)、漢(han)堡心(xin)(xin)(xin)(xin)(xin)臟(zang)驟(zou)停研(yan)究(jiu)(CASH)、美國心(xin)(xin)(xin)(xin)(xin)、肺(fei)和血(xue)液研(yan)究(jiu)所埋(mai)藏(zang)(zang)式(shi)(shi)心(xin)(xin)(xin)(xin)(xin)臟(zang)復(fu)律(lv)除顫(zhan)器(qi)(NHLBHCD)等有(you)的已(yi)經(jing)完成,有(you)的正(zheng)在進行,最后將揭示ICD防治(zhi)心(xin)(xin)(xin)(xin)(xin)臟(zang)性(xing)猝死(si)的確(que)切價值。
從心臟性猝死復蘇過來的幸運者在1年內發生致命性心律失常的復發率達25%~30%。已有試驗表明,ICD能有效轉復心臟性猝死患者的復發性心室顫動。Newman等對心臟驟停復蘇過來的幸存者進行了回顧性研究,60例患者植入ICD而120例患者僅僅使用藥物治療,兩組病例的年齡、左心室射血分數、心律失常類型、基礎心臟病和藥物治療情況相似。結果,ICD植入者的心臟性猝死率降低50%(10%∶5%,P<0.01),3年實際病死率降低31%(51%∶35%,P<0.01),5年的生存曲線也有明顯差異。但是,也必須注意,許多心臟性猝死幸存者(20%~70%)最后并不一定死于致命性心律失常,大約5%的心臟性猝死幸存者死于電-機械分離,而ICD對這種類型的心律失常無效。
①經導管(guan)射頻消(xiao)融治療(liao)室性(xing)心律失常(chang):室性(xing)心動過(guo)速(su)發(fa)作時常(chang)引起嚴重(zhong)的(de)(de)血流(liu)動力學障礙,心臟性(xing)猝(cu)死的(de)(de)發(fa)生(sheng)率(lv)高。1988年,Davis首(shou)次使用(yong)射頻消(xiao)融治療(liao)室性(xing)心動過(guo)速(su)成(cheng)(cheng)功,開創(chuang)射頻消(xiao)融的(de)(de)新領域(yu),但至今仍不如室上性(xing)心動過(guo)速(su)使用(yong)普遍。室性(xing)心動過(guo)速(su)的(de)(de)消(xiao)融,成(cheng)(cheng)功的(de)(de)關(guan)鍵之一是心動過(guo)速(su)的(de)(de)起源定位(wei),其方(fang)法(fa)是進(jin)行心內(nei)膜標(biao)測(ce)(ce),一般根(gen)據(ju)Josephson提出(chu)的(de)(de)18個(ge)點標(biao)測(ce)(ce),左心室12,右心室6個(ge),標(biao)測(ce)(ce)方(fang)法(fa)有(you)3種:
A.竇性心律(lv)時(shi)的標(biao)測(ce):
在竇性心律下,在心室的不同部位尋找有明顯延遲碎裂電位的部位。延遲破裂電位是缺血區殘存心肌纖維的非同步除極,常常被大量結締組織所包繞,彼此連接較少,因此傳導很慢,形成緩慢傳導區,成為室性心動過速折返環的重要組成部分。在低倍放大條件下,延遲碎裂電位表現為高頻成分組成的低振幅波(<1mV),持續100ms以上。但必須注意,延遲破裂電位僅僅表示該部位有傳導延緩。并不表示一定為室性心動過速的起源部位,因此,竇性心律下的標測是不可靠的。
B.起搏標測:
用電極(ji)在心(xin)(xin)室的不同部位(wei)作(zuo)心(xin)(xin)內(nei)膜起(qi)搏,起(qi)搏頻(pin)(pin)率(lv)與心(xin)(xin)動(dong)(dong)(dong)過(guo)速(su)(su)的頻(pin)(pin)率(lv)相(xiang)同,記錄12導(dao)(dao)聯(lian)心(xin)(xin)電圖,若11個以(yi)上導(dao)(dao)聯(lian)的圖形與心(xin)(xin)動(dong)(dong)(dong)過(guo)速(su)(su)發作(zuo)時(shi)的相(xiang)同,可認為該起(qi)搏部位(wei)即是心(xin)(xin)動(dong)(dong)(dong)過(guo)速(su)(su)的起(qi)源(yuan)部位(wei),但起(qi)搏標測也(ye)不可靠。
C.心動(dong)過(guo)速時的標(biao)測:
有(you)心(xin)(xin)(xin)動過速發作時,在心(xin)(xin)(xin)室(shi)內不同部(bu)(bu)位記錄心(xin)(xin)(xin)內膜(mo)電圖,比(bi)較哪一(yi)部(bu)(bu)位的(de)(de)(de)心(xin)(xin)(xin)室(shi)激動時間比(bi)體表心(xin)(xin)(xin)電圖的(de)(de)(de)QRS波(bo)提前,則最早(zao)激動的(de)(de)(de)部(bu)(bu)位是心(xin)(xin)(xin)動過速的(de)(de)(de)起源點(dian)。心(xin)(xin)(xin)運過速的(de)(de)(de)標測是室(shi)性心(xin)(xin)(xin)動過速定位的(de)(de)(de)較可(ke)靠(kao)方法。
準確(que)定位后,行射頻消(xiao)融,一般(ban)用30~40W,10~30s。成功的因素是:精(jing)確(que)的起(qi)搏標(biao)測;最早(zao)的局部心(xin)室(shi)激(ji)動(dong);導(dao)管電(dian)極(ji)與心(xin)內(nei)膜密切接觸(chu)。失敗的因素是:消(xiao)融電(dian)極(ji)未到達(da)起(qi)源點;導(dao)管電(dian)極(ji)與心(xin)內(nei)膜接觸(chu)不緊(jin)密;室(shi)性心(xin)動(dong)過速的起(qi)源點位于心(xin)肌內(nei)或(huo)心(xin)外膜。
不(bu)同(tong)類型的(de)(de)室速(su),消(xiao)融(rong)的(de)(de)療效不(bu)同(tong),其中,無器質(zhi)心(xin)臟病的(de)(de)特發性室速(su),成功率(lv)(lv)達94%。束支折(zhe)(zhe)(zhe)返(fan)性心(xin)動(dong)(dong)過(guo)(guo)速(su),是由希氏-心(xin)肌傳導(dao)系統參與的(de)(de)大(da)(da)折(zhe)(zhe)(zhe)返(fan),消(xiao)融(rong)右束即可(ke)(ke)終(zhong)止室速(su),成功率(lv)(lv)超過(guo)(guo)90%。目前(qian)較困難的(de)(de)是梗死后(hou)室性心(xin)動(dong)(dong)過(guo)(guo)速(su)成功率(lv)(lv)不(bu)高,一般在(zai)(zai)45%~93%,差異較大(da)(da),其原因在(zai)(zai)于梗死性心(xin)動(dong)(dong)過(guo)(guo)速(su)的(de)(de)機(ji)制較復雜所(suo)致。梗死后(hou)室性心(xin)動(dong)(dong)過(guo)(guo)速(su)的(de)(de)射(she)頻(pin)消(xiao)融(rong),包括以下幾(ji)種(zhong)情形:a.瘢(ban)痕(hen)周(zhou)(zhou)圍(wei)折(zhe)(zhe)(zhe)返(fan):必須在(zai)(zai)瘢(ban)痕(hen)組(zu)織(zhi)周(zhou)(zhou)圍(wei)產(chan)(chan)生較大(da)(da)損傷,折(zhe)(zhe)(zhe)返(fan)才能終(zhong)止;b.瘢(ban)痕(hen)內折(zhe)(zhe)(zhe)返(fan):大(da)(da)部分(fen)病例可(ke)(ke)用射(she)頻(pin)消(xiao)融(rong)成功;c.功能性折(zhe)(zhe)(zhe)返(fan):射(she)頻(pin)消(xiao)融(rong)常常無效。有(you)時(shi),射(she)頻(pin)消(xiao)融(rong)術后(hou)可(ke)(ke)在(zai)(zai)功能性上折(zhe)(zhe)(zhe)返(fan)的(de)(de)基礎上,增加一個解剖(pou)性因素而(er)產(chan)(chan)生更為頑固的(de)(de)折(zhe)(zhe)(zhe)返(fan)性心(xin)律失常。
②經皮(pi)球囊冠狀動脈成形術治(zhi)療冠心(xin)(xin)(xin)病。從(cong)理(li)論上(shang)講,經皮(pi)球囊冠狀動脈形成術治(zhi)療冠心(xin)(xin)(xin)病應(ying)能有效降(jiang)低心(xin)(xin)(xin)臟性(xing)猝死的發生率。當迄今未見到多中心(xin)(xin)(xin)隨機臨(lin)床觀察資料。
①室(shi)性心(xin)律(lv)失常的外科(ke)治(zhi)療:
近10幾年來,用手術(shu)切割、冷凍或激光等手段可成功地控制或根治室性(xing)心(xin)動(dong)過速(su)/或心(xin)室顫動(dong),從而(er)減少(shao)心(xin)臟性(xing)猝死的發生率。
A.內膜病灶切除術:
這種治療方(fang)法于1979年(nian)由Harken用于臨床,其方(fang)法是首先進行(xing)病(bing)灶(zao)(zao)(zao)定位(wei)。Harken等(deng)的(de)方(fang)法是在(zai)常溫體外循環下,用手持移動電極在(zai)心(xin)(xin)內(nei)膜面進行(xing)標測(ce),找出最早(zao)心(xin)(xin)室激(ji)動部位(wei),經左心(xin)(xin)室切口對標測(ce)出來的(de)最早(zao)心(xin)(xin)室激(ji)動部位(wei)作直徑2~3cm厚約(yue)數毫米的(de)盤狀切除。心(xin)(xin)內(nei)膜病(bing)灶(zao)(zao)(zao)切除術適用于病(bing)灶(zao)(zao)(zao)局限(xian),尤(you)其適用于位(wei)于室壁瘤邊(bian)緣而遠離心(xin)(xin)臟傳導系統和乳頭肌的(de)病(bing)灶(zao)(zao)(zao)。
B.心(xin)內(nei)膜環(huan)形心(xin)室(shi)肌切除術:
對(dui)于(yu)(yu)有室(shi)壁瘤而(er)伴發室(shi)性(xing)心動過速的患者可在室(shi)壁瘤邊(bian)緣的正(zheng)常心內膜作弧(hu)形切口,深達心肌層(ceng),直到(dao)僅留(liu)一層(ceng)靠(kao)近心外膜的肌橋。該(gai)法由Guiraudon等于(yu)(yu)1987年首創(chuang)。因術后左室(shi)受損,現已少(shao)用。
C.心(xin)室隔離(li)術(shu):
僅適(shi)用于右(you)心室游離壁或(huo)右(you)心室流(liu)出(chu)道(dao)的(de)病灶。其方法是以右(you)房溝為(wei)基底,圍繞某一分(fen)(fen)支血管對可疑(yi)心室壁做半島狀切開,使(shi)它和右(you)心室壁的(de)其余部分(fen)(fen)分(fen)(fen)離。
D.外科冷凍消(xiao)融術:
對于靠近心臟傳(chuan)導(dao)系統(tong)或腱索的病灶(zao),直接進行(xing)外科手術切除術可發(fa)生嚴重的并發(fa)癥,則宜在(zai)外科手術直視(shi)下進行(xing)冷凍治療,使病灶(zao)降溫至0℃持續(xu)1min。如(ru)果有(you)效則降溫至-60℃持續(xu)2min。
E.外科激光消融術:
用激光代(dai)替冷凍而消除心律失常的病灶(zao)。
②冠狀動脈旁路術:
對(dui)于嚴(yan)重(zhong)冠(guan)狀動(dong)脈病(bing)變(bian)的(de)(de)患(huan)者進(jin)行冠(guan)狀動(dong)脈旁(pang)路術(shu)可有(you)效的(de)(de)改善(shan)心(xin)肌供血,減輕或消除心(xin)絞痛的(de)(de)癥狀。已有(you)一些多中心(xin)研究結(jie)果(guo)顯(xian)示(shi),冠(guan)狀動(dong)脈旁(pang)路術(shu)可延長冠(guan)心(xin)病(bing)患(huan)者的(de)(de)生存期(qi),但對(dui)心(xin)臟性(xing)猝死發生率的(de)(de)影響,所見報道極少。
(1)判斷意識
拍雙肩,喚雙耳(er),搭(da)脈搏,10秒鐘內完成
(2)呼(hu)救(撥打120)
完成第(di)一(yi)步后,馬上拔打120,給病人爭取救治的第(di)一(yi)時間。
(3)擺放仰臥體(ti)位
(4)胸外按壓(ya)30次(ci)(兒童15次(ci))
位置:胸部正中,兩乳頭連線中點;
姿勢:肩關節、肘關節、腕關節垂直成一條直線。
雙手掌重(zhong)疊,手指抬起;掌根用力(li)。
力度:按下去至少5cm;
頻率:至(zhi)少100次(ci)/分鐘;
(5)開(kai)放氣道(仰頭(tou)舉頦法)
(6)人工吹氣2次(兒童1次)捏鼻,口包口,吹氣
(7)重復第四、五、六步
(8)注意事(shi)項:研究發(fa)現,倒地1分鐘內(nei)進行(xing)心肺(fei)復蘇,救(jiu)活的概率為90%;2分鐘內(nei)60%;4分鐘內(nei)40%;8分鐘內(nei)為20%;超過10分鐘,基本上就是零(ling)了(le)。為了(le)預防(fang)心源(yuan)性(xing)猝死,中、老年人和肥胖者(zhe)、糖尿病(bing)者(zhe)、應定期到醫(yi)院檢查(cha),發(fa)現潛在性(xing)心血管病(bing)就及時治療,并(bing)應防(fang)止各種(zhong)誘(you)發(fa)因素。
飲食適宜
建(jian)議適當(dang)限制辛辣生冷刺激性食物。缺血(xue)性心臟病(bing)常(chang)伴有高(gao)(gao)血(xue)壓高(gao)(gao)血(xue)脂(zhi)(zhi)糖(tang)尿病(bing),如果你同時伴有以上疾(ji)病(bing),可針對給予低(di)鹽(yan)低(di)脂(zhi)(zhi)低(di)糖(tang)飲(yin)食。
建議平(ping)時飲(yin)食(shi)(shi)清淡,不(bu)可集(ji)中食(shi)(shi)用(yong)過多蔬(shu)菜或高脂(zhi)食(shi)(shi)物,低鹽低脂(zhi)飲(yin)食(shi)(shi),少吃動(dong)物的(de)內臟,多喝水,避免辛辣(la)和(he)(he)生冷(leng),戒煙酒,適當(dang)運(yun)動(dong)鍛(duan)煉(lian),保(bao)(bao)持樂(le)觀舒暢的(de)心情,保(bao)(bao)持良好的(de)睡眠,不(bu)要(yao)長(chang)時間熬夜,放(fang)松精(jing)神,心態平(ping)和(he)(he)。
飲食禁忌
紅肉(rou):這些肉(rou)類含有大量阻塞(sai)動脈的飽和脂肪,不利(li)于(yu)心臟健康。
汽(qi)水(shui):汽(qi)水(shui)含有大量單糖和熱量,是引起兒童和成人肥(fei)胖的食品(pin)之一。
薯(shu)條(tiao):薯(shu)條(tiao)含有飽和(he)(he)脂肪(fang)和(he)(he)轉脂肪(fang),會引起人(ren)們(men)肥胖,增加心(xin)臟病(bing)風險(xian)。
(1)定期(qi)體檢(jian):老年人(ren)本身是心臟病(bing)及各種疾病(bing)的高發(fa)人(ren)群(qun),應定期(qi)到醫院進行(xing)(xing)體檢(jian)。青、中年人(ren)工作緊張(zhang)、生活節奏(zou)快、工作生活壓力大(da)也容易(yi)患冠心病(bing)、高血(xue)壓等疾病(bing)。定期(qi)體檢(jian)及早(zao)檢(jian)查(cha)便于及時(shi)發(fa)現疾病(bing),及早(zao)進行(xing)(xing)治(zhi)療,減少猝死風險。
(2)避免過度疲(pi)勞(lao)和精神緊張:過度疲(pi)勞(lao)和精神緊張會使機體處于(yu)應激狀(zhuang)態(tai),使血壓升高,心臟負(fu)擔加(jia)重,使原(yuan)(yuan)有(you)(you)(you)心臟病(bing)加(jia)重。即使原(yuan)(yuan)來沒有(you)(you)(you)器質性心臟病(bing)也(ye)會引發室顫的發生(sheng)。所(suo)以,每個人應該對自己的工作、生(sheng)活有(you)(you)(you)所(suo)安(an)排,控制工作節奏和工作時間,不可(ke)過快(kuai)過長。
(3)戒煙、限(xian)酒、平衡膳食、控制體重(zhong)、適當運動,保持良好的(de)生(sheng)活習慣會(hui)減少心腦血管(guan)疾病的(de)發(fa)生(sheng)。
(4)注(zhu)意(yi)過度(du)疲勞的(de)危險信(xin)號及重(zhong)視發(fa)病的(de)前兆(zhao)癥狀:長(chang)期過度(du)疲勞會(hui)引發(fa)身體出(chu)現(xian)一些改變。如(ru)焦慮易怒、記憶力減退(tui)、注(zhu)意(yi)力不(bu)集(ji)中、失眠及睡眠質(zhi)量差、頭痛頭暈耳(er)鳴、性功能(neng)減退(tui)、脫發(fa)明(ming)顯(xian)等。當(dang)機體出(chu)現(xian)這些情況,應調整工作節(jie)奏、適(shi)當(dang)休息(xi),調整節(jie)奏,保持愉快的(de)心情。讓(rang)機體功能(neng)得以恢(hui)復。如(ru)不(bu)能(neng)緩(huan)解(jie),應立即前往醫院救治(zhi)。
(5)對已患有冠心病(bing)、高血壓等疾病(bing)的患者應在醫生指導下(xia)堅持服藥治療。
(6)注(zhu)意對室性心律失常進行危險評估(gu),包括進行常規心電(dian)(dian)圖、動態(tai)心電(dian)(dian)圖、其他心電(dian)(dian)學技術、超(chao)聲(sheng)心動圖、心內電(dian)(dian)生理檢查等檢查,以明確(que)心律失常類型,評估(gu)心臟猝死風險,做出治療決策。
(7)注(zhu)意(yi)加強心梗后心臟猝死的預防。