OBJECTIVE
To analyze the causes and structure of arterial and venous bypass graft dysfunction in various morphofunctional systems (graft-artery junction) within 10 years after coronary artery bypass grafting (CABG).
MATERIAL AND METHODS. W
E visually analyzed 102 angiograms in late postoperative period after CABG. Causes and structure of dysfunctions were established throughout more than 10-year follow-up period.
RESULTS
Dysfunctions accounted for 28.8% of all grafts (occlusions — 81.7%, stenoses — 18.3%). Dysfunctions of venous grafts comprised 34%, left internal thoracic artery (LITA) — 20.1%, right ITA (RITA) — 26%, radial artery (RA) — 41.6%. Stenoses in LITA-right coronary artery (RCA) system occurred in 3 (17.8%) cases, RITA-RCA — 3 (17.8%), vein-diagonal artery (DA) — 1 (5.8%), vein-RCA — 5 (29.2%), vein-obtuse marginal artery 1 (OMA) — 3 (17.8%), vein-OMA2 — 1 (5.8%), RA-RCA — 1 (5.8%). Occlusion of LITA-LAD was noted in 12 (15.8%) cases, LITA-DA — 4 (5.3%), LITA-OMA1 — 2 (2.6%), RITA-LAD — 3 (4%), RITA-RCA — 5 (6.6%), RITA- OMA1 — 2 (2.6%), vein-DA — 9 (12%), vein- OMA1 — 12 (15.8%), vein- OMA2 — 2 (2.6%), vein-RCA — 21 (27.5%), RA-RCA — 2 (2.6%), RA- OMA1 — 2 (2.6%). The causes of stenosis in 2 (11.8%) cases were poor distal coronary bed, in 2 (11.8%) cases — progression of atherosclerosis of bypassed coronary arteries, in 5 (29.4%) cases — competitive blood flow, in 8 (47%) cases — graft degeneration. The causes of occlusion were poor distal coronary bed — 38 (50%), progression of atherosclerosis in bypassed coronary arteries — 1 (1.3%), competitive blood flow — 29 (38.1%), graft degeneration — 3 (4%), unclear cause — 5 (6.6%) cases.
CONCLUSION
LITA graft patency was 80%, vein patency — 66%. The main cause of venous graft dysfunction was poor distal bed and degeneration following atherosclerosis. In case of arterial grafts, the main cause was competitive blood flow also explaining «disuse atrophy» phenomenon.