Single versus sequential saphenous vein grafting of the circumflex system: a flowmetric study

OBJECTIVE: We sought to evaluate if patients with proximal critical circumflex (CX) lesions did better with single SV-CABG on the best obtuse marginal (OM), or with sequential SV-CABG on two OM branches. DESIGN: Ninety patients were prospectively randomised to single SV-CABG on the best OM (sSV-CABG-45 patients; Group A) or to sequential SV-CABG on 2 OM (seqSV-CABG 45 patients; Group B). Transit-time flowmetry (TTF), and graft flow reserve were evaluated. Recurrent angina, acute myocardial infarction, readmission for coronary reintervention were defined "treatment failure" during follow-up. RESULTS: SeqSV-CABG showed better intraoperative maximum (119.1+/-57.5 ml/min vs. sSV-CABG 62.4+/-29.6; p=0.001), mean (56.3+/-31.5 ml/min vs. 30.8+/-12.8; p=0.0001), minimum flow (22.8+/-9.2 ml/min vs. 11.8+/-8.9; p=0.001) and P.I. (0.71+/-0.4 vs.1.46+/-0.9; p=0.006). Graft flow reserve also proved to be higher (95.4+/-29.7 ml/min mean flow vs. sSV-CABG 42.3+/-15.2 ml/min mean flow; p=0.0001; flow reserve 1.72+/-0.99 vs 1.32+/-1.09; p=0.001) as well as freedom from treatment failure (97.5+/-0.5% vs 88.7+/-0.4%; p=0.05). CONCLUSIONS: SeqSV-CABG showed higher TTF flows, with no incremental risk for perioperative morbidity. Higher flows and graft flow reserve may allow lower treatment failure at mid-term follow-up.