Bigi R, Galati A, Curti G, Coletta C, Barlera S, Partesana N, Bordi L, Ceci V, Occhi G, Fiorentini C
Division of Cardiac Rehabilitation, E. Morelli Hospital, Sondalo, Italy.
Eur Heart J. 1997 Dec;18(12):1873-81. doi: 10.1093/oxfordjournals.eurheartj.a015195.
Risk stratification after uncomplicated myocardial infarction is major clinical problem. In particular, the prognostic value of residual inducible ischaemia is still controversial. We compared the relative prognostic value of exercise ECG and dobutamine stress echocardiography performed in the early post-infarction period.
Four hundred and six patients (53 female) aged 57 +/- 9 years, undergoing maximal exercise ECG and dobutamine stress echocardiography within 10 days of an uncomplicated myocardial infarction off therapy, were prospectively followed-up for 8.8 months. Age, sex, diabetes, smoking habit, hypertension, dyslipidaemia, infarct location, thrombolysis and resting wall motion score index were taken into account among clinical variables. Prognostic correlations were made vs spontaneous events (cardiac death, non-fatal reinfarction and unstable angina requiring hospitalization) whilst patients undergoing revascularization (by means of percutaneous transluminal coronary angioplasty or coronary artery bypass surgery) at the time of the procedure were censored.
One hundred and twenty-seven events occurred during the follow-up: 41 (10%) were spontaneous (five deaths, 12 reinfarctions and 24 unstable angina) and 86 procedural (27 angioplasty and 59 bypass surgery). Spontaneous events were not predicted by any clinical, exercise ECG or dobutamine stress echocardiography variable, but the negative predictive value of both tests was excellent (91% and 90% respectively). With a multivariate Cox analysis, male gender, positive low-workload (< 100 W) exercise ECG (P < 0.0001), positive low-dose dobutamine stress echocardiography (P < 0.0001) and rest-stress wall motion score index variation (P < 0.001) were found to predict cumulative cardiac events with an independent and additive value. Dobutamine stress echocardiography was significantly more sensitive (P < 0.05) and less specific (P < 0.01) in predicting the outcome of patients with anterior infarction, whilst exercise ECG was significantly more sensitive (P < 0.05) in patients with non-Q wave infarction.
(1) Spontaneous events are poorly predicted by provocative tests in low-risk patients after uncomplicated myocardial infarction. (2) However, both exercise ECG and dobutamine stress echocardiography can predict a favourable outcome with a very high negative predictive value. (3) Dobutamine stress echocardiography should be considered a secondary option in cases where the exercise ECG is equivocal or when the location of ischaemia is a relevant issue. (4) The possibility that the two tests have a differential utility depending on the infarct location and type (Q wave vs non-Q wave) may be clinically relevant and deserves further evaluation.
非复杂性心肌梗死后的风险分层是一个主要的临床问题。特别是，残余诱发性缺血的预后价值仍存在争议。我们比较了在心肌梗死后早期进行的运动心电图和多巴酚丁胺负荷超声心动图的相对预后价值。
406例患者（53例女性），年龄57±9岁，在未接受治疗的非复杂性心肌梗死后10天内接受了最大运动心电图和多巴酚丁胺负荷超声心动图检查，并进行了为期8.8个月的前瞻性随访。临床变量包括年龄、性别、糖尿病、吸烟习惯、高血压、血脂异常、梗死部位、溶栓治疗及静息壁运动评分指数。对自发性事件（心源性死亡、非致命性再梗死和需要住院治疗的不稳定型心绞痛）进行预后相关性分析，而在检查时接受血运重建（经皮冠状动脉腔内血管成形术或冠状动脉旁路移植术）的患者被排除。
随访期间发生了127起事件：41起（10%）为自发性事件（5例死亡、12例再梗死和24例不稳定型心绞痛），86起为手术相关事件（27例血管成形术和59例旁路手术）。任何临床、运动心电图或多巴酚丁胺负荷超声心动图变量均不能预测自发性事件，但两种检查的阴性预测值均极佳（分别为91%和90%）。多因素Cox分析显示，男性、低负荷（<100W）运动心电图阳性（P<0.0001）、低剂量多巴酚丁胺负荷超声心动图阳性（P<0.0001）和静息-负荷壁运动评分指数变化（P<0.001）可独立且累加地预测累积心脏事件。多巴酚丁胺负荷超声心动图在预测前壁梗死患者的预后时敏感性显著更高（P<0.05），特异性更低（P<0.01），而运动心电图在非Q波梗死患者中敏感性显著更高（P<0.05）。
（1）非复杂性心肌梗死后低风险患者的激发试验对自发性事件的预测效果较差。（2）然而，运动心电图和多巴酚丁胺负荷超声心动图均可通过极高的阴性预测值预测良好预后。（3）当运动心电图结果不明确或缺血部位是一个相关问题时，多巴酚丁胺负荷超声心动图应被视为次要选择。（4）两种检查根据梗死部位和类型（Q波与非Q波）具有不同效用的可能性可能具有临床相关性，值得进一步评估。
