Pfisterer M E, Buser P, Osswald S, Weiss P, Bremerich J, Burkart F
Department of Internal Medicine, University Hospital, Basel, Switzerland.
J Am Coll Cardiol. 1998 Jul;32(1):97-102. doi: 10.1016/s0735-1097(98)00188-0.
We sought to test the hypothesis that late recanalization of infarct-related coronary arteries (IRAs) improves long-term left ventricular (LV) function.
Reperfusion within 24 h of an acute myocardial infarction (MI) has been shown to improve myocardial healing and to reduce infarct expansion. Uncontrolled data suggest that there may be a time window of several weeks for such an effect.
Sixteen asymptomatic patients 10 +/- 4 days after a first Q wave anterior wall MI with persistent left anterior descending coronary artery occlusion and infarct-zone akinesia were randomized to immediate (2 weeks) or delayed (3 months) angioplasty. Repeat catheterization and cardiac magnetic resonance imaging (MRI) were performed after 3 and 12 months.
Angiography 3 months after MI revealed that LV ejection fraction (LVEF) had increased ([mean +/- SD] 54.4 +/- 4.3% vs. 63.9 +/- 7.4%, p < 0.01) as a result of improved regional function (p < 0.01) and LV end-systolic volume had decreased (p < 0.002), whereas LV end-diastolic volume remained unchanged. With delayed angioplasty, LVEF, infarct zone wall motion and LV volumes did not improve. Cardiac MRI at baseline and at 3 and 12 months confirmed these findings and extended them up to 1 year, indicating that delayed angioplasty could no longer improve LV function because of marked LV dilation (p < 0.01). Immediate angioplasty had a high success rate, but restenosis (50%) was accompanied by new severe angina as a clinical indicator of salvaged myocardium, which did not occur after delayed angioplasty.
This pilot study in selected patients supports the hypothesis that myocardial viability persists ("hibernation") for 2 to 3 weeks but not for 3 months after MI, during which time it may be worthwhile to restore blood flow to a large myocardial territory, even in asymptomatic patients, to improve long-term LV function.
我们试图验证梗死相关冠状动脉（IRA）的晚期再通可改善长期左心室（LV）功能这一假说。
急性心肌梗死（MI）后24小时内进行再灌注已被证明可改善心肌愈合并减少梗死扩展。未经控制的数据表明，这种效应可能存在数周的时间窗。
16例首次Q波前壁心肌梗死后10±4天、左前降支冠状动脉持续闭塞且梗死区运动减弱的无症状患者被随机分为即刻（2周）或延迟（3个月）血管成形术组。在3个月和12个月后进行重复导管检查和心脏磁共振成像（MRI）。
心肌梗死后3个月的血管造影显示，由于局部功能改善（p<0.01），左心室射血分数（LVEF）增加（[均值±标准差]54.4±4.3%对63.9±7.4%，p<0.01），左心室收缩末期容积减小（p<0.002），而左心室舒张末期容积保持不变。延迟血管成形术时，LVEF、梗死区壁运动和左心室容积未改善。基线及3个月和12个月时的心脏MRI证实了这些发现，并将其延长至1年，表明由于明显的左心室扩张（p<0.01），延迟血管成形术不再能改善左心室功能。即刻血管成形术成功率高，但再狭窄（50%）伴有新的严重心绞痛，作为挽救心肌的临床指标，延迟血管成形术后未出现这种情况。
这项针对特定患者的初步研究支持以下假说：心肌梗死后心肌存活性可持续（“冬眠”）2至3周，但不是3个月，在此期间，即使是无症状患者，恢复大面积心肌区域的血流以改善长期左心室功能可能是值得的。
