Eek Christian, Grenne Bjørnar, Brunvand Harald, Aakhus Svend, Endresen Knut, Smiseth Otto A, Edvardsen Thor, Skulstad Helge
Department of Cardiology, Rikshospitalet University Hospital, Oslo, Norway.
Eur J Echocardiogr. 2011 Jul;12(7):483-9. doi: 10.1093/ejechocard/jer055. Epub 2011 May 24.
Differentiation between necrotic and viable myocardium is difficult in the setting of acute myocardial infarction (MI). Post-systolic shortening (PSS) has been proposed as a marker of recovery after revascularization, but has not previously been assessed in patients with NSTEMI prior to revascularization. In this study, we aimed to examine the relation between PSS and improvement of contractile function after successful revascularization.
Thirty-five patients with non-segment elevation MI and regional systolic dysfunction were examined immediately prior to revascularization, and at follow-up 9 ± 3 months after successful revascularization. Regional systolic function was assessed by speckle tracking echocardiography as regional strain, expressed as mean peak negative longitudinal strain in segments supplied by the culprit artery. Recovery of systolic function was assessed as the difference between regional strain at follow-up and baseline (ΔStrain). Post-systolic shortening was defined as shortening in diastole beyond minimum systolic length. By multivariate regression analysis, several other variables that may affect viability were also assessed. Post-systolic shortening was observed in 32 patients (91%), mean -1.9 ± 1.4%. Mean ΔStrain was -3.3 ± 2.9%. After adjustment for baseline systolic function, PSS (β = 0.77, P= 0.022), and angiographic severity were independent predictors of viability by multiple regression analysis. Interestingly, troponin T was not a significant predictor.
Post-systolic shortening is associated with improved myocardial function after revascularization in patients with acute MI. It predicts long-term systolic function, and provides information on the potential benefit of the procedure.
在急性心肌梗死（MI）情况下，区分坏死心肌和存活心肌很困难。收缩期后缩短（PSS）已被提议作为血运重建后恢复的标志物，但此前尚未在非ST段抬高型心肌梗死（NSTEMI）患者血运重建前进行评估。在本研究中，我们旨在探讨PSS与成功血运重建后收缩功能改善之间的关系。
35例非ST段抬高型心肌梗死且有局部收缩功能障碍的患者在血运重建前即刻接受检查，并在成功血运重建后9±3个月进行随访。通过斑点追踪超声心动图评估局部收缩功能，以局部应变表示，即罪犯血管供血节段的平均负向纵向峰值应变。收缩功能的恢复以随访时与基线时的局部应变差值（Δ应变）来评估。收缩期后缩短定义为舒张期缩短超过最小收缩期长度。通过多变量回归分析，还评估了其他几个可能影响心肌存活的变量。32例患者（91%）观察到收缩期后缩短，平均为-1.9±1.4%。平均Δ应变为-3.3±2.9%。在调整基线收缩功能后，通过多元回归分析，PSS（β = 0.77，P = 0.022）和血管造影严重程度是心肌存活的独立预测因素。有趣的是，肌钙蛋白T不是一个显著的预测因素。
急性心肌梗死患者血运重建后，收缩期后缩短与心肌功能改善相关。它可预测长期收缩功能，并提供有关该手术潜在益处的信息。
