Predictors of success in bypass to the distal segment of completely occluded coronary arteries.

Suitability for grafting and efficacy of aortocoronary bypass to the completely occluded coronary artery were studied in 25 patients in whom bypasses were attempted to the segments distal to the complete occlusion. We concluded that even when a coronary artery is occluded completely, if the distal coronary artery has a suitable lumen and viable muscle remains, bypass to the segment distal to the occlusion is worthwhile. Bypasses on the left anterior descending arteries were successfully constructed in 80% of grade 3 patients where distal segments of occlusion were severely compromised. Thallium-201 stress-myocardial scintigraphy is reliable in confirming myocardial viability beyond the area of complete coronary artery occlusion.