The Reliability Of Angiography In Predicting Quality And Caliber Of The Distal Coronary-Artery Lumen In Preparation For Bypass-Surgery

To determine whether coronary arteriograms accurately predict the presence of distal coronary lumena that are inadequate for bypass because of diffuse disease and/or small caliber, angiographic grading of distal lumen (DL) caliber was carried out on 867 diseased coronary arteries on which bypass was subsequently attempted. Where the DL was graded as normal, bypasses could be successfully constructed in 96% of cases. Where the general DL caliber was normal but one or more localized distal stenoses were present, bypasses could be successfully constructed in 95.6% of cases. Where the DL caliber was reduced to a mild-moderate degree angiographically, bypasses were successfully constructed in 83.6%. Where the DL had a severely reduced caliber or could not be visualized at all, bypasses were successfully constructed in 73.0%. Thus, even when a severely narrowed or totally occluded DL appears present, bypass can still be performed in almost 75% of cases. The angiographic diagnosis of a nongraftable distal segment is therefore unreliable and patients should not be denied bypass on this basis alone.