Full-motion pulse inversion power Doppler contrast echocardiography differentiates stunning from necrosis and predicts recovery of left ventricular function after acute myocardial infarction.

OBJECTIVES: The goal of this study was to determine, in patients with a recent myocardial infarction (MI) and residual wall motion abnormalities within the distribution of the infarct-related artery, whether normal perfusion by myocardial contrast echocardiography (MCE) would accurately predict recovery of segmental left ventricular (LV) function. BACKGROUND: Left ventricular dysfunction after acute MI may be secondary to myocardial stunning or necrosis. Recent technical innovations in contrast echocardiography, including pulse inversion imaging and power Doppler, now allow full-motion echocardiographic perfusion assessment from a venous injection of fluorocarbon-based contrast agent. METHODS: Thirty-four patients with recent MI underwent baseline wall motion assessment and MCE two days after admission and follow-up echocardiography a mean of 55 days later. RESULTS: Perfusion by MCE predicted recovery of segmental function with a sensitivity of 77%, specificity of 83%, positive predictive value of 90% and overall accuracy of 79%. The mean wall motion score at follow-up was significantly better in perfused, compared with nonperfused, segments (1.4 vs. 2.2, p < 0.0001). Additionally, 90% of perfused segments improved, while the majority of nonperfused segments remained unchanged. CONCLUSIONS: Full-motion MCE utilizing an intravenous fluorocarbon-based agent and pulse inversion power Doppler techniques, identifies stunned myocardium, and accurately predicts recovery of segmental LV function in patients with recent MI.

Enhanced endocardial visualization with noncontrast harmonic imaging during stress echocardiography.

The diagnostic value of echocardiography hinges on the reader's ability to adequately visualize the endocardium of the left ventricle. This study was designed to evaluate the potential benefit of noncontrast harmonic imaging to enhance endocardial visualization. Eighty consecutive outpatients who underwent treadmill stress echocardiography were randomly assigned to either fundamental or harmonic imaging. The echoes were interpreted by 2 experienced readers. Compared with fundamental imaging, harmonic imaging of tissue improved the overall endocardial visualization score by 35% and 21% for readers 1 and 2, respectively (P <.001). Harmonic imaging also reduced the percentage of nondiagnostic segments by one half (P <.01). In patients undergoing treadmill stress echo, harmonic imaging offers a clinically significant improvement in endocardial visualization.