Myocardial Contrast Echocardiography Demonstrates That Collateral Flow Can Preserve Myocardial Function Beyond a Chronically Occluded Coronary Artery

Assessment of collateralized myocardium with Cardiac Magnetic Resonance (CMR): Transmural extent of infarction but not angiographic collateral vessel filling determines regional function and perfusion in collateral-dependent myocardium

“…Furthermore, perfusion and function were not different in regions with good vs. poor angiographic collateral vessel filling. It has been shown earlier that angiographically visualized collateral vessels do not always imply the presence of viable myocardium [19] and there is a poor correlation between angiographic collateral vessel filling and myocardial function or perfusion [6]. Our study confirms these earlier results.…”

“…Similarly, a poor correlation between perfusion or wall motion and angiographic collateral filling has been reported [6,19]. Among other things, this has been related to limited image resolution of standard coronary angiography, with inability to detect collaterals less than 100 μm diameter.…”

“…Furthermore, assessment of coronary collaterals might be relevant for drug treatment in patients with coronary artery disease (CAD) since drugs such as β-blockers commonly used in these patients might hamper collateral perfusion [5]. While standard angiographic collateral vessel filling [6] shows a weak correlation between regional myocardial perfusion or function, additional testing with pressure/flow wire provides reliable data of collateral circulation complementary to coronary angiography [7]. Non-invasive techniques would facilitate the clinical approach to assess coronary collateral circulation.…”

Quantitative contrast echocardiographic assessment of collateral derived myocardial perfusion during elective coronary angioplasty

“…Grill et al studied 24 patients without coronary occlusion and found that contrast echocardiography using subsequent ipsilateral and contralateral intracoronary contrast injections was capable of mapping the collateral receiving territory and detecting changes in collateral supply induced by angioplasty 22. In 21 patients with previous myocardial infarction, left ventricular wall motion abnormality, and a chronically occluded coronary artery, Vernon et al showed a positive correlation between regional wall motion score and collateral receiving area size determined by contrast echocardiography after intracoronary contrast injections, indicating that collateral derived perfusion is associated with preserved regional function in patients with total coronary occlusion 23. Interestingly, no correlation between wall motion and angiographic collateral grade was found in that study, proving the inability of angiography to provide sufficient relevant functional information on coronary collaterals.…”

Techniques for Phenotyping Coronary Artery Disease in the Cardiac Catheterization Laboratory for Applications in Translational Research

“…The 100 um resolution of angiography exceeds the size of most collateral channels, rendering them invisible by this technique. Further, angiography only reveals epicardial collateral channels and fails to provide information on myocardial perfusion, thus limiting their value as a quantitative tool [14,15]. Quantification of recruitable collaterals is more accurately accomplished by the use of fractional collateral flow reserve, described in the current issue of this journal [3].…”