aVR导联T波直立对心血管性死亡的预测意义

Clinical significance of discordant T waves in lead aVR for predicting cardiovascular death

健康人群中心电图T波异常很常见,但aVR导联T波直立的临床意义及其与心血管病的关系尚不清楚。美国和芬兰健康人群中aVR导联T波直立者,其心血管性死亡风险比T波倒置者高出5倍。冠心病陈旧性心肌梗死(old myocardial infarction,OMI)患者aVR导联T波直立者,其心脏终点事件的发生率均显著升高;前壁OMI伴aVR导联T波直立者,其血流动力学改变更严重。冠心病缺血性心肌病患者aVR导联T波直立与心脏骤停密切相关,其心脏骤停的发生率显著高于T波倒置者。aVR导联T波直立对潜在心肌病患者、慢性肾病实施肾透析患者的不良预后具有重要的预测意义,对应激性心肌病与急性心肌梗死的鉴别诊断也有重要价值。aVR导联T波直立的病理生理机制与左心功能不全、心室壁应力增加、心肌梗死后心肌运动异常以及心肌梗死后心肌去神经化所致的复极异常等有关。

Abnormal T waves are commonly seen in ECGs of healthy people,however the clinical significance of discordant T wave in lead aVR and its relationship with cardiovascular diseases has not been found. In America and Finland,the risk of cardiovascular death among healthy people with discordant T waves in lead aVR is 5 times higher than those with concordant T waves. For the patients with coronary heart disease( CHD) and old myocardial infarction( OMI),the incidence of cardiac endpoint events significantly increases among those with discordant T waves in lead aVR.For the patients with anterior OMI complicated by discordant T waves in lead aVR,hemodynamic changes are worsened. For CHD patients with ischemic cardiomyopathy,discordant T waves in lead aVR is closely related to sudden cardiac arrest and the incidence of sudden cardiac arrest is significantly higher than those with concordant T waves. The electrophysiological phenomenon of discordant T waves in lead aVR plays an important role in predicting the poor prognosis of the patients with potential cardiomyopathy and those with chronic kidney disease undergoing renal dialysis. It is also clinically valuable in making differential diagnosis between stress cardiomyopathy and acute myocardial infarction. The physiopathologic mechanism of discordant T waves in lead aVR is related to various factors including left cardiac insufficiency,increased ventricular wall stress,abnormal myocardi-al motion after myocardial infarction,and repolarization abnormality caused by denervation of myocardium after myocardial infarction.