title: Late coronary bypass graft flow: quantitative assessment by roentgendensitometry.
abstract: Quantitative assessment of the flow in 45 saphenous vein aortocoronary bypass grafts in 30 patients was performed by a roentgendensitometric technique. Detalis of the technique are given. Mean graft flow for all grafts measured in the early postoperative period (two weeks) and again in the late postoperative period (six months to 3 years; average, 1.5 years) significantly decreased (72.6 +/- 34.7 to 57.4 +/- 28.6 ml/min; p less than 0.01). Mean graft diameter also significantly decreased over the same period (3.5 +/- 0.6 to 3.0 +/-  0.6 mm; p less than 0.01). Differences could not be related to graft site or to the time interval between early and late recatheterization. Changes in diameter did not correlate with changes in flow. During a 3-year follow-up, saphenous vein grafts significantly decreased in diameter and flow but still functioned adequately; and vein grafts generally remained larger than the recipient arteries. The determinant of adequacy of flow is the native coronary bed.
mesh_terms: D015502:Absorptiometry, Photon / Q000379:methods*; D000328:Adult; D000368:Aged; D001783:Blood Flow Velocity; D002932:Cineangiography / Q000379:methods*; D017023:Coronary Angiography; D001026:Coronary Artery Bypass; D003326:Coronary Circulation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged