Left ventricular remodeling and heart failure in diabetic patients treated with primary angioplasty for acute myocardial infarction

Background-Diabetes mellitus has been recognized as a strong predictor of heart failure (HF) in patients with acute myocardial infarction ( AMI). However, considerable controversy exists regarding the pathogenetic mechanisms of HF after AMI in diabetic patients. We hypothesized that the increased incidence of HF in diabetic patients was associated with a greater propensity for left ventricular (LV) remodeling. Methods and Results-A series of 325 patients ( 42 diabetics) with AMI successfully treated with primary angioplasty underwent serial 2D echocardiography from admission to 1 and 6 months and 6-month angiography. No significant difference was found between diabetics and nondiabetics regarding baseline clinical, angiographic, and echocardiographic characteristics, as well as 6-month restenosis and reocclusion rates. At 6 months, a similar incidence of LV remodeling was observed in diabetics and nondiabetics (33% versus 25%; P = 0.234), with similar patterns of changes in LV volumes and LV global and regional systolic function. At 5 years, the incidence of HF was higher in the diabetics (43% versus 20%, P = 0.001). Diabetes was found to be an independent predictor of HF at 5 years (hazard ratio, 1.8; P = 0.0366). However, LV remodeling was predictive of HF in the nondiabetics (P = 0.023) but not in the diabetics (P = 0.123). In a subgroup of patients, higher LV chamber stiffness ( as assessed by echocardiography) was detected in the diabetics with HF. Conclusions-The more frequent progression to HF in the diabetics after AMI is not explained by a greater propensity for LV remodeling. Other factors, such as diastolic dysfunction, may play a role.