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.

OBJECTIVES 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. BACKGROUND Ischemic insult after coronary occlusion affects not only regional LV systolic but also diastolic function. METHODS 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. RESULTS 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. CONCLUSIONS 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.