Viability Tested with Dobutamine Stress Echocardiography and Prognosis Early after Acute Myocardial Infarction: A Meta-Analysis

In non-high risk patients treated without primary PCI for acute myocardial infarction (AMI), the updated American Heart Association/American College of Cardiology guidelines recommend a selective pharmacoinvasive strategy (IIb, level C). Early risk assessment is essential to select patients with an increased risk for ischemic events or cardiac death. A potential prognostic value has been ascribed to viability in the infarct region. Viability-testing with Low Dose Dobutamine echocardiography (LDDE) can safely be performed in the early phase after AMI. Since the prognostic value of viability after acute myocardial infarction remains unclear and is still debated, we performed a meta-analysis of post-infarction studies to elucidate the importance and prognostic value of viability early after AMI. The literature was scanned by formal searches of electronic databases from 1966 to June 2010. We used the following selection criteria for inclusion in this meta-analysis: a) viability testing with LDDE within 14 days after Acute Myocardial Infarction (AMI), b) preserved left ventricular function (ejection fraction(EF) ≥40% or wall motion score index (WMSI) ≤1.9), c) prognosis scored by clinical endpoints (death, AMI or unstable angina (UA)). Eight observational studies were included in the meta-analysis (2301 patients). Results: The presence of viability was strongly associated with an increase in ischemic cardiac events [OR 5.0 (1.53 - 16.36), p=0.008]. No predictive value was found for mortality [OR 0.91 (0.38 - 2.18), p=0.84]. In conclusion, patients with preserved left ventricular function and proven viability early after AMI are at risk for ischemic cardiac events, without any difference in mortality (Metaanalysis, acute myocardial infarction, viability, echocardiography).