Identification of stunned myocardium with parametric imaging-based, quantitative myocardial contrast echocardiography...

Microvascular integrity demonstrated by myocardial contrast echocardiography (MCE) predicts functional recovery after an acute myocardial infarction (AMI). Recently, parametric imaging-based quantitative MCE has been developed. Our aim was to assess the usefulness of parametric imaging-based quantitative MCE parameters to predict the functional recovery of akinetic segments after primary percutaneous transluminal coronary angioplasty (PTCA). Fifty-three consecutive patients with a first AMI were enrolled. They underwent primary PTCA. Standard echocardiography and real-time MCE were performed. Qualitative analysis and parametric imaging-based quantitative parameters were measured offline by different blinded investigators. Dobutamine stress echocardiography was performed 1 month later. A new standard echocardiogram to assess the functional status of the akinetic segments and coronary angiography to evaluate the presence of restenosis at the level of the culprit lesion were performed 6 months later. The mean patient age was 62.9 +/- 14 years, and 42 were men (79%); 170 segments were akinetic. Of these, 105 (62%) recovered their function. The best parameter to predict functional recovery was the myocardial blood flow velocity (beta). These results were better than those obtained using dobutamine stress echocardiography and qualitative MCE to predict functional recovery. In conclusion, parametric imaging-based quantitative MCE is an accurate diagnostic tool to detect stunned myocardium after AMI. Its diagnostic accuracy in predicting the functional recovery of akinetic segments after primary PTCA is better than the accuracy of dobutamine stress echocardiography and qualitative MCE.