Microvascular Obstruction and Left Ventricular Remodeling Early After Acute Myocardial Infarction

Author:

Gerber Bernhard L.1,Rochitte Carlos E.1,Melin Jacques A.1,McVeigh Elliot R.1,Bluemke David A.1,Wu Katherine C.1,Becker Lewis C.1,Lima João A. C.1

Affiliation:

1. From the Cardiology Division, Department of Medicine, and Department of Radiology, Johns Hopkins School of Medicine, Baltimore, Md, and the Division of Cardiology, University of Louvain, Brussels, Belgium (J.A.M.).

Abstract

Background —The presence of microvascular obstruction (MO) within infarcted regions may adversely influence left ventricular (LV) remodeling after acute myocardial infarction. This study examined whether the extent of MO directly alters the mechanical properties of the infarcted myocardium. Methods and Results —Seventeen dogs underwent 90 minutes of balloon occlusion of the left anterior descending coronary artery, followed by reperfusion. Gadolinium-enhanced perfusion MRI and 3D-tagging were performed 4 to 6 and 48 hours (8 animals) and 10 days (9 animals) after reperfusion. Early increase in LV end-diastolic volume (from 42±9 to 54±14 mL, P <0.05) between 4 to 6 and 48 hours after reperfusion was predicted by both extent of MO ( r =0.89, P <0.01) and infarct size ( r =0.83, P <0.01), defined as MRI hypoenhanced and hyperenhanced regions, respectively. Multivariate analysis demonstrated that extent of MO had better and independent value to predict LV volume than overall infarct size. A strong inverse relationship existed between magnitude of first principal strain ( r =−0.80, P <0.001) and relative extent of MO within infarcted myocardium. Also, infarcted myocardium involved by extensive areas of MO demonstrated reductions of circumferential ( r =−0.61, P <0.01) and longitudinal ( r =−0.53, P <0.05) stretching. Furthermore, significant reductions of radial thickening (9±6% versus 14±3%, P <0.01) occurred in noninfarcted regions adjacent to infarcts that had increased (>35%) amounts of MO. Conclusions —In the early healing phase of acute myocardial infarction, the extent of MO in infarcted tissue relates to reduced local myocardial deformation and dysfunction of noninfarcted adjacent myocardium. Such strain alterations might explain the increased remodeling observed in patients with large regions of MO.

Publisher

Ovid Technologies (Wolters Kluwer Health)

Subject

Physiology (medical),Cardiology and Cardiovascular Medicine

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3