Persistent ST-segment elevation after primary stenting for acute myocardial infarction: its relation to left ventricular recovery.
BACKGROUND
Early restoration of coronary artery patency in acute myocardial infarction (AMI) has been linked to improvement in survival. However, early recanalization of an occluded epicardial coronary artery by either thrombolytic agents or percutaneous transluminal coronary angioplasty (PTCA) does not necessarily lead to left ventricular (LV) function recovery.


OBJECTIVE
The aim of this study was to evaluate the relation between persistent ST elevation shortly after primary stenting for acute myocardial infarction (AMI) and LV recovery.


METHODS
Thirty-one patients with primary stenting for AMI were prospectively enrolled. To evaluate the extent of microvascular injury, serial ST-segment analysis on a 12-lead electrocardiogram recording just before and at the end of the coronary intervention was performed. Persistent ST-segment elevation (Persistent Group, n = 11) was defined as > or = 50% of peak ST elevation and resolution (Resolution Group, n = 20) was defined as < 50% of peak ST elevation. Echocardiography was performed on Day 1 and 3 months after primary stenting.


RESULTS
At 3 months, infarct zone wall-motion score index (WMSI, 2.1 +/- 0.6 vs. 2.7 +/- 0.3, p < 0.05) was smaller in the Resolution Group than in the Persistent Group, whereas wall motion recovery index (RI, 0.4 +/- 0.3 vs. 0.1 +/- 0.2, p < 0.05) and ejection fraction (58 +/- 5 vs. 43 +/- 10%, p < 0.05) were larger in the Resolution Group than in the Persistent Group. The extent of persistent ST elevation (% ST) shortly after successful recanalization of the infarct-related artery was significantly related to RI at 3 months (r = -0.4, p < 0.05). However, time to reperfusion was not related to RI at 3 months. There was also significant correlation between corrected TIMI frame count and %ST (r = 0.4, p < 0.05).


CONCLUSIONS
Persistent ST-segment elevation shortly after successful recanalization (> or = 50% of the peak value), as a marker of impaired microvascular reperfusion, predicts poor LV recovery 3 months after primary stenting for AMI.
Lee
San-Gon
SG
Department of Medicine, Ulsan University Hospital, Dong-go, Korea. sglee@uuh.ulsan.kr
Cheong
Jong-Pil
JP
Shin
Je-Kyoun
JK
Kim
Jin-Woo
JW
Park
Jae-Hoo
JH
D000368:Aged; D019917:Blood Vessel Prosthesis Implantation; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000150:complications / Q000503:physiopathology* / Q000601:surgery*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D020127:Recovery of Function / Q000502:physiology*; D015607:Stents; D013997:Time Factors; D014654:Vascular Patency / Q000502:physiology; D018487:Ventricular Dysfunction, Left / Q000209:etiology* / Q000503:physiopathology* / Q000601:surgery