Diagnostic Value of Angiographic Collateral Vessels to Determine Myocardial Viability

Diagnostic value of angiographic collateral vessels to eletermine myocardial viability in severe asynergic regions was investigated in patients with chronic coronary artery disease. For this purpose, 30 consecutive patients with at least one completely occluded major coronary artery supplying severe asynergic myocardial regions were evaluated. Collateral vessels were graded as grade l (none), grade 2 (minimal) and grade 3 (well developed) according to the degree of distal opasification of the totally occluded vessel. Myocardial viability was determined by exercise planar Tl-20 1 myocard perfusion scintigraphy (MPS) with reinjection method. Myocardial regions which had at least 50% activity in redistribution or reinjection images were accepted as viable. To evaluate wall motion and compare them with MPS, a left ventriculography model consisted of 1 O regions was established. There were 37 completely occluded vessels. Thirtythree of them were major, 4 were minor vessels. Of the 125 severe asynergic regions related with completely occluded vessels; 79, 46 and 3 of them were supplied by grade 3, grade 2 and grade 1 collateral vessels respectively. Sixtyseven of 76 regions supplied by grade 3 collaterals, 39 of 46 regions with grade 2 and 2 of 3 regions supplied with grade 1 collaterals were viable. It is concluded, in patients depicted above, well developed collateral vessels have a high predictive value for myocardial viability bul the presence of minimal or absent angiographic collateral flow does not indicate the nonviable myocardium.