Abstract 2727: Extent of Myocardial Viability Detected by Myocardial Contrast Echocardiography Early after Acute Myocardial Infarction is An Independent Predictor of Hard Cardiac Events
Background Myocardial viability (MV) detected by myocardial contrast echocardiography (MCE) has been shown to predict recovery of left ventricular (LV) function in patients with acute myocardial infarction (AMI). However, to date no study has shown its value to predict major adverse outcomes in such patients.
Methods Accordingly, 95 stable AMI patients underwent low power MCE at 7±2 days after thrombolysis. Contrast perfusion index (CPI), a measure of residual myocardial viability, was obtained by adding contrast score(1=homogenous;2=reduced;3=minimal/absent opacification) in all 16 LV segments divided by 16. At discharge 65 (68%) patients had either undergone or were scheduled for revascularization independent of the MCE result. The patients were subsequently followed up for cardiac death, AMI and emergency revascularization.
Results During the mean follow up time of 46±16 months, there were 21 cardiac events (21%) of which, 8 were cardiac deaths, 5 AMIs and 8 emergency revascularizations. Amongst the clinical, biochemical and echocardiographic markers of prognosis, the extent of residual MV was the only independent predictor of cardiac death (p=0.001); cardiac death or AMI (p=0.001); and cardiac death or AMI or emergency revascularization (p=0.001) apart from age which was also found to be an independent predictor of cardiac death (p=0.03). Cardiac death occured in only 1% of patients with significant MV (CPI of ≤1.81) compared to 27% in patients demonstrating lack of MV (p=0.0004). (Figure⇓)
Conclusion The extent of residual myocardial viabilty as assessed by MCE is a powerful predictor of hard cardiac events in patients following AMI and thrombolysis.