Abstract-In the thrombolytic era, hypertension has been shown to adversely affect the development of heart failure after acute myocardial infarction (AMI). We sought to examine the relation between antecedent hypertension and heart failure after mechanical reperfusion and to test the impact of postinfarction left ventricular remodeling on heart failure in hypertensive patients. A series of 953 patients (324 hypertensives) with AMI treated with successful primary percutaneous coronary intervention underwent a 5-year follow-up. A subgroup of 325 subjects underwent 2D echocardiography at admission, 1 month, and 6 months. From day 1 to 6 months, despite similar improvement in regional and global left ventricular function and similar 6-month infarct artery patency rate, left ventricular end-diastolic volume increased in the normotensives (122Ϯ36 mL to 131Ϯ47 mL; PϽ0.001) but not in the hypertensives (127Ϯ41 mL to 128Ϯ31 mL; Pϭ0.768). At 6 months, the incidence of left ventricular remodeling in hypertensive and normotensive patients was not different (22% versus 28%; Pϭ0.210). However, at 5 years, the incidences of hospitalization for heart failure (7% versus 3%; Pϭ0.014) and of New York Heart Association functional class Ն2 (53% versus 40%; PϽ0.001) were higher in hypertensive as compared with normotensive patients. Hypertension was found to be a predictor of heart failure (hazard ratio, 2.23; Pϭ0.015). In conclusion, patients with antecedent hypertension are at higher risk to develop heart failure after AMI, even when successfully reperfused by primary percutaneous coronary intervention. However, the increased incidence of heart failure in hypertensive patients is not associated with a greater propensity to postinfarction left ventricular remodeling. Key Words: heart failure Ⅲ hypertrophy Ⅲ remodeling Ⅲ coronary artery disease Ⅲ myocardial infarction H ypertension is a well-known risk factor for coronary artery disease and heart failure. It has been shown that after thrombolysis for acute myocardial infarction (AMI), antecedent hypertension increases the risk of heart failure (HF) and other adverse events. [1][2][3][4][5] The progression to HF after AMI is mainly related to left ventricular (LV) remodeling. 6 However, animal 7,8 and human studies 5,9,10 evaluating the relation between hypertension and early LV remodeling after AMI have yielded conflicting or inconclusive results.Several studies have demonstrated that mechanical reperfusion (primary percutaneous coronary intervention, PCI) is superior to pharmacological reperfusion (thrombolysis), because it allows brisk and sustained flow achievement in the infarct-related artery (IRA) in a higher proportion of patients with subsequent improved myocardial salvage and better long-term outcome. 11 Thus, in the last decade, an increasing number of centers have adopted primary PCI as the preferred reperfusion therapy for AMI.In this study, we sought to examine the relation between antecedent hypertension and the development of HF after successful primary PCI for AMI. An...