Abnormal regional left ventricular systolic and diastolic function in patients with coronary artery disease undergoing percutaneous coronary intervention: clinical significance of post-ischemic diastolic stunning.

Abstract

This study was designed to characterize both regional left ventricular (LV) systolic and diastolic function after percutaneous coronary intervention by using strain imaging (SI) derived from 2-dimensional speckle-tracking echocardiography. Ischemic insult after coronary occlusion affects not only regional LV systolic but also diastolic function. Regional LV transverse peak strain and strain changes during the first one-third of diastole duration (strain imaging diastolic index [SI-DI]) were monitored in at-risk segments after percutaneous coronary intervention in 30 patients with coronary artery disease. The segments were divided into proximal and distal. Strain data in the at-risk segments were compared with values derived from remote nonischemic segments. Coronary occlusion induced a marked reduction in the systolic strain in both proximal and distal at-risk segments (from 36.9 +/- 6.0% to 12.0 +/- 3.9% and from 31.9 +/- 5.6% to 6.2 +/- 3.3%, respectively, p < 0.0001). Concomitantly, SI-DI values decreased (from 76.6 +/- 5.3% to -21.2 +/- 9.1% and from 72.5 +/- 5.9% to -48.7 +/- 20.8%, respectively, p < 0.0001). Upon reperfusion, systolic deformation parameters returned to near-normal pre-occlusion values. However, SI-DI values in the both proximal and distal at-risk segments decreased (43.2 +/- 9.5%, p < 0.01, and -17.3 +/- 11.1%, p < 0.0001, respectively) 30 min after reperfusion and were still lower (51.5 +/- 9.9%, p < 0.01) in the distal at-risk segment 24 h after reperfusion. SI analysis provides detailed mechanical characterization of regions with myocardial ischemic insult and can demonstrate post-ischemic diastolic stunning despite complete systolic functional recovery after reperfusion.