Abstract 582: Impact of Duration of Ischemia on Left Ventricular Diastolic Properties Following Reperfusion for Acute Myocardial Infarction
Background: The duration of ischemia is an important determinant of left ventricular systolic function and survival following acute ST-elevation myocardial infarction (STEMI). However, the impact of the duration of ischemia on left ventricular diastolic properties following reperfusion for AMI has not been previously studied. A restrictive filling pattern is correlated with significant diastolic dysfunction and elevated filling pressures. We determined the correlation between the symptom-to-reperfusion time and the finding of a restrictive filling pattern in patients undergoing primary angioplasty (PAMI) for STEMI.
Methods: A total of 99 consecutive patients undergoing PAMI had a transthoracic echocardiogram performed on day 3 following their procedure. A restrictive filling pattern was recognized as a deceleration time of <140 ms or an E/A ratio of >2.0. Follow-up obtained at 2 years on all patients determined cumulative rates of major adverse cardiovascular events (MACE) (death, reinfarction, heart failure or revascularization).
Results: The mean age of patients was 63±13 years, 71% were males, 60 patients (61%) had hypertension and 20 patients (20%) had diabetes. The left anterior descending artery was the culprit artery in 48 patients (49%). The symptom-to-reperfusion time in the whole group was 295±196 minutes, and the mean biplane LVEF at day 3 was 50±8%. A total of 20 patients (20%) had a restrictive filling pattern (RFP) on day 3. The symptom-to-reperfusion time in the RFP group was 407±91 minutes compared to 264±150 minutes in the non-restrictive filling pattern (Non-RFP) group (p = 0.04). A total of 8 patients (40%) in the RFP had a MACE event, compared to 6 patients (8%) in the Non-RFP group (p <0.001). In a multivariate model incorporating baseline clinical and angiographic characteristics and LVEF at day 3, a restrictive filling pattern was the only independent predictor of MACE at 2 years (HR 3.8 (95%CI 1.7–7.2, p <0.001).
Conclusions: Delayed reperfusion following acute myocardial infarction was associated with a restrictive diastolic filling pattern, which in turn was strongly correlated with adverse long-term outcomes. Minimising the duration of ischemia may preserve diastolic function and hence improve prognosis in this setting.