Multidisciplinary Cardiovascular Research Centre & Leeds Institute of Genetics, Health and Therapeutics, University of Leeds, Great George St, Leeds LS2 9JT, England.
Radiology. 2013 Jun;267(3):701-8. doi: 10.1148/radiol.12121516. Epub 2013 Feb 4.
To compare the relationship of myocardial edema and corresponding contractile function over time in patients with reperfused acute myocardial infarction (AMI).
This study was approved by the regional ethics committee; all patients gave written informed consent. Thirty-nine patients (34 men; mean age, 57 years; age range, 35-73 years) underwent T2-weighted, tagging, and late gadolinium enhancement magnetic resonance imaging at three time points after primary percutaneous coronary intervention for ST-elevation AMI. Circumferential strain, T2-weighted signal intensity, and volume of infarct zones, peri-infarct zones, and remote myocardium were measured. Patients were stratified by presence or absence of peri-infarct edema, defined as areas with T2-weighted signal intensity of two or more standard deviations above that of remote myocardium. Statistical analysis was performed with repeated-measures analysis of variance with post hoc Bonferroni correction.
Edematous peri-infarct myocardium had attenuated strain compared with remote myocardium at day 2 (-0.137 vs -0.226, P < .001), day 30 (-0.188 vs -0.240, P < .01), and day 90 (-0.207 vs -0.241, P = .01). Nonedematous peri-infarct myocardium had similar (P > .05) strain to remote myocardium at all time points. Strain improved in edematous peri-infarct myocardium at day 30 (P = .02) and day 90 (P < .01), closely mirroring resolution of intensity and volume of edema. Decreased strain correlated with edema volume (r = 0.30, P = .01) and normalized edema signal intensity (r = 0.28, P < .01). In eight patients with fully transmural infarction, infarct zone strain improved between day 2 and day 90 (P = .02).
Improvement of strain in peri-infarct myocardium closely follows regression of myocardial edema. Volume of edema and intensity of signal on T2-weighted images relate to functional recovery after reperfused AMI.
比较再灌注急性心肌梗死(AMI)患者心肌水肿及其相应收缩功能随时间的变化关系。
本研究经地区伦理委员会批准,所有患者均签署了书面知情同意书。39 名患者(34 名男性;平均年龄 57 岁;年龄 35-73 岁)在首次经皮冠状动脉介入治疗 ST 段抬高型 AMI 后 3 个时间点进行 T2 加权、标记和晚期钆增强磁共振成像。测量梗死区、梗死周边区和远隔心肌的周向应变、T2 加权信号强度和容积。根据 T2 加权信号强度比远隔心肌高两个或两个以上标准差的区域是否存在梗死周边水肿,将患者分为存在或不存在梗死周边水肿。采用重复测量方差分析和事后 Bonferroni 校正进行统计学分析。
与远隔心肌相比,第 2 天(-0.137 比-0.226,P <.001)、第 30 天(-0.188 比-0.240,P <.01)和第 90 天(-0.207 比-0.241,P =.01)时,水肿性梗死周边心肌的应变减弱。在所有时间点,非水肿性梗死周边心肌的应变与远隔心肌相似(P >.05)。第 30 天(P =.02)和第 90 天(P <.01),水肿性梗死周边心肌的应变增加,与水肿的强度和容积消退密切相关。应变与水肿体积(r = 0.30,P =.01)和标准化水肿信号强度(r = 0.28,P <.01)呈负相关。在 8 例完全透壁性梗死患者中,梗死区应变在第 2 天和第 90 天之间改善(P =.02)。
梗死周边心肌应变的改善与心肌水肿的消退密切相关。T2 加权图像上的水肿体积和信号强度与再灌注 AMI 后的功能恢复有关。