MYOCARDIAL CONTRAST ECHOCARDIOGRAPHY IN HUMAN-BEINGS - CORRELATION OFRESTING PERFUSION DEFECTS TO SESTAMIBI SINGLE-PHOTON EMISSION COMPUTED-TOMOGRAPHY

The presence of myocardial perfusion abnormalities is generally accept ed to suggest underlying coronary artery disease. In previous animal s tudies, myocardial contrast echocardiography (MCE) has been shown to b e useful in delineating areas at risk after coronary occlusions. We so ught to compare the presence or absence, size, and location of perfusi on defects detected in human beings by MCE and sestamibi single photon emission computed tomography (SPECT). Regional wall motion was qualit atively assessed in the parasternal and apical views of a resting two- dimensional echocardiogram. Coronary angiography was performed in all patients and myocardial contrast echocardiography performed with 2 ml of intracoronary sonicated meglumine (Nycomed). A cine loop of the dig itized contrast echocardiograms was used to analyze perfusion defects. Gated SPECT resting images in standard views were obtained after tech netium 99m sestamibi (20 mCi) was administered. Visually perceived per fusion defects were established at 30% of maximal counts at end diasto le. Perfusion defects by both techniques were planimetered, assigned t o one of three perfusion artery territories, and expressed as a percen tage of the perfusion territory studied. Comparison was made by linear regression analysis. Forty-one patients were studied. Perfusion defec ts were observed in 12 (29%) patients by MCE, 19 (46%) patients by SPE CT, and 11 (27%) patients by both techniques. No perfusion defects wer e detected by MCE in 29 (70%) patients, by SPECT in 22 (53%) patients, or by either technique in 21 (51%) patients. The two techniques agree d in 78% of the patients. In 67 matching orthogonal views suitable for comparison between the two techniques, an 82% concordance for the pre sence or absence of defects was observed. The location of the defects matched in 86% of the cases. A significant correlation (p < 0.001; r = 0.62) between these techniques was observed in assessing the size of perfusion defects. In conclusion, our results suggest that MCE and ses tamibi SPECT are comparable techniques for detecting severely underper fused myocardium in human beings.