Left ventricular remodeling and systolic deterioration in acute myocardial infarction: findings from the Stent-PAMI Study.

Background: Left ventricular systolic deterioration (LVSD) develops in some patients despite successful percutaneous intervention and medical therapy for myocardial infarction (MI). We sought to determine predictors of LVSD by comparing demographic, procedural, angiographic variables, and 6-month major adverse cardiac events (MACE) in patients with and without LVSD after MI.
Methods: We performed a posthoc analysis of patients prospectively enrolled in the Stent-PAMI trial if they had successful percutaneous intervention for MI (<50% residual stenosis and TIMI-3 grade flow), normal left ventricular systolic function on index ventriculogram, and protocol driven coronary angiography with ventriculography at 6 months. We defined LVSD as an absolute decrease in ejection fraction > or =15% compared to baseline value.
Results: Of the 900 patients enrolled in Stent-PAMI, 187 patients met the inclusion criteria. LVSD developed in 30 patients (16%) and occurred independent of demographic, procedural, angiographic variables, and 6-month MACE. Multivariate predictors of LVSD were higher baseline ejection fraction (P = 0.0065, OR 1.09; 95% CI = 1.02-1.16) and peak creatine phosphokinase (CPK) level (P = 0.0022, OR 1.04; 95% CI = 1.02-1.07).
Conclusions: LVSD occurs in a minority of patients despite successful mechanical reperfusion and occurred independent of procedural, angiographic variables, target vessel revascularization, reinfarction, and combined MACE. Infarct size (determined by peak CPK) and high baseline ejection fraction predicted development of LVSD at 6 months. LVSD in this population likely occurred by negative left ventricular remodeling.