Observation of the Ischemic Cascade in Humans Using Contrast Echocardiography During Dobutamine Stress

Experimental studies have postulated the ischemic cascade and the present study was designed to elucidate whether it can be observed in the clinical setting. Fifty-three patients suspected of having coronary artery disease were studied. Myocardial perfusion abnormalities (MPA) and wall motion abnormalities (WMA) were assessed simultaneously by infusion of Levovist during dobutamine stress echocardiography. Time - intensity data of myocardial opacification were fitted for Y=A (1-e-β t) from which the rate of increase (β) of intensity were derived both at rest and during stress. Wall motion was also given a score. Bright opacification was observed in 50 patients: 25 showed significant stenosis (>50%) in the left anterior descending artery (group II) on coronary angiography and 25 did not (group I). Significant differences were found in the β ratio (stress/rest) between the 2 groups at a low-dose (2.0±0.3 vs 1.5±0.5, p