Coronary blood flow assessment after successful angioplasty for acute myocardial infarction predicts the risk of long-term cardiac events

Background - Analysis of coronary flow velocity (CFV) in the recanalized infarct-related coronary artery (IRA) with a Doppler guidewire is useful for predicting recovery of regional left ventricular function, in-hospital complications, and survival. We postulated that the CFV pattern after IRA reperfusion for acute myocardial infarction (AMI) would predict long-term adverse cardiac events. Methods and Results - Sixty-eight consecutive patients with a first AMI underwent CFV measurement with a Doppler guidewire after successful reopening of the IRA by coronary angioplasty. At the end of follow-up, 3.8 +/- 1.7 years after AMI, 44 of the 65 surviving patients (67.7%) were free of long-term cardiac events. Univariate analysis showed that the following factors were predictive of an end point combining cardiac death, recurrent MI, and congestive heart failure: hypertension, age greater than or equal to65 years, time from onset of chest pain to PTCA greater than or equal to6 hours, peak creatine kinase >4000 IU/L, ejection fraction less than or equal to50%, proximal left anterior descending artery occlusion, resting average peak velocity less than or equal to10 cm/s, average systolic peak velocity less than or equal to5 cm/s, a rapid diastolic deceleration time (less than or equal to600 ms), and early retrograde systolic flow. In the final multivariate model, only age greater than or equal to65 years (OR, 3.6; 95% CI, 1.1 to 11.8; P = 0.03), time to PTCA greater than or equal to6 hours (OR, 2.9; 95% CI, 1.0 to 8.3; P = 0.04), and a rapid diastolic deceleration time (OR, 5.4; 95% CI, 1.5 to 19.3; P = 0.01) were independent predictors. Conclusions - The CFV pattern appears to be an accurate predictor of long-term cardiac events in patients having undergone successful reopening of the IRA after AMI, identifying a subset of at-risk patients.