Contrast echocardiography for evaluation of myocardial perfusion: Effects of coronary angioplasty

Abstract

Assessment of viable myocardium before and after interventional therapy has become a critical issue in modern cardiology. This report describes a new contrast echocardiographic technique using conventional two-dimensional imaging during direct intracoronary injections of small volumes (1.5 to 2.0 cc) of sonicated Renografin-76. Contrast echocardiography was performed before and after coronary angioplasty in seven patients with single vessel coronary artery disease. Before angioplasty a contrast (that is, perfusion) defect was noted in all seven patients. This defect correlated with the anatomic distribution of the epicardial coronary stenosis. After angioplasty the mean gradient across the stenotic lesion decreased from 52 +/- 11 to 13 +/- 14 mm Hg (p less than 0.01) in association with a fall in the mean diameter of the lesion from 84 +/- 8 to 29 +/- 13% (p less than 0.001). Increased myocardial perfusion to the area of "contrast defect" was demonstrated in only five of the seven patients, despite hemodynamically and angiographically successful angioplasty. Thus, contrast echocardiographic techniques performed during interventional therapy and used in conjunction with standard coronary angiographic procedures may provide additional physiologic information regarding regional myocardial perfusion after attempts at revascularization.

Study of Coronary Flow Reserve with Intravenous Use of Microbubbles (Contrast Echocardiography) and Adenosine: Protocol for Clinical Application in Patients Suspected of Having Coronary Heart Disease

“…This observation is supported by a study by Lang et al 52 , who showed that the increase in the intensity of contrast is greater in the regions related to obstructed arteries that undergo angioplasty than in regions related to normal arteries due to subsequent hyperemia.…”

Combined Assessment of Myocardial Perfusion and Regional Left Ventricular Function by Analysis of Contrast-Enhanced Power Modulation Images

“…1,7 Contrast echocardiography is increasingly referred to as a technique that could potentially allow quantification 4 -6 or at least imaging of myocardial perfusion. 2,3,8,16,17 This goal, however, still remains a great challenge. 18 Although LV opacification for improved endocardial visualization is better established than perfusion imaging, it is qualitative, because there is no technique to automatically detect the endocardial border from contrast-enhanced images.…”

Visualization of subendocardial myocardial ischemia with myocardial contrast echocardiography in humans.

“…22,28 Quantification, rather than the presence or absence of the enhanced contrast, was investigated in experimental studies.24, 25 Kemper et a125 showed that the amount of contrast enhancement can provide quantitative information about myocardial blood flow. A recent clinical study20 showed that measurement of peak contrast intensity after intracoronary injections of contrast medium provides a relative index of myocardial perfusion that allows assessment of regional coronary reserve in patients with coronary artery disease.…”