The assessment of myocardial perfusion using contrast echocardiography

: A brief survey is given on the state of the art of qualitative and quantitative myocardial contrast echocardiography as well as on the contrast agents used. Exact qualitative assessment of coronary perfusion areas is possible. In addition, myocardial areas of collaterals of less than 100 microns in diameter can be visualized and measured that were not seen by routine coronary angiography. Quantitative analysis was done in 5 normal subjects and 16 patients with coronary artery disease before and after right ventricular stimulation (170 bpm over 75 s). While decay half time (T1/2) remained unchanged in normal subjects before and after pacing (7 +/- 4 s vs 7 +/- 5 s), it increased significantly from 5 +/- 1 to 16 +/- 1 s in patients with coronary stenoses between 50% and 75%. Stenotic area reduction greater than 75% had significant prolongations of T 1/2 = 12 +/- 7 s already at rest with further prolongation to 36 +/- 17 s (p less than 0.05) after pacing. Regional wall motion in these areas, however, was not significantly altered either in the fixed axis or floating axis system. Following dipyridamole hyperaemia (0.56 mg/kg i.v.), normal subjects showed a significant shortening of T 1/2 (6 +/- 2 vs 1.6 +/- 1; p less than 0.01; n = 5), while T 1/2 of patients with multiple vessel disease was prolonged from 9 +/- 6 to 15 +/- 6 s (p less than 0.01; n = 7). This prolongation was not uniform, since some myocardial areas were found to be hyperaemic after dipyridamole. One patient showed an opening of antegrade collaterals following dipyridamole. In first results myocardial contrast echocardiography proved capable of recognizing ischaemic and hyperaemic myocardium.(ABSTRACT TRUNCATED AT 250 WORDS)