Radial artery graft flowmetry is better than saphenous vein on postero-lateral wall

Although general agreement exists on internal mammary graft as the first conduit, the second choice is still questioned. Despite radial artery (RA) grafting has been suggested, saphenous veins (SV) continue to be extensively used.

A prospective series of isolated RA-CABG (150 patients) or SV-CABG (180 patients), performed either off-pump (OP-CABG) and on-pump (CPB-CABG), in diabetics and non-diabetics, in elderly and young patients, during the last 5-years at a single institution were evaluated. RA was harvested with harmonic scalpel, flowmetry was performed with a transit-time flowmeter (TTF). Graft flow reserve (GFR) was calculated with intra-aortic balloon-pump. Follow-up was collected by outpatient clinic database or by telephone interview with general practitioners.

The 2 groups showed comparable preoperative and intraoperative variables. Mortality, morbidity, myocardial infarction, troponin I leakage, and echocardiographic parameters were comparable (p=NS). RA-CABG demonstrated significantly higher TTF maximum, mean and minimum flow (p<.001) with lower Pulsatility Index (p<.001), either in the circumflex and the right coronaries. Compared to SVG-grafting, significantly higher GFR was found in RA-CABG on the circumflex (p=.001) and right (p=.028) coronaries. 38.1+/-0.9 SE months follow-up resulted in higher survival and freedom from cardiac events in RA-CABG. Better TTF and GFR were demonstrated in OP-CABG, CPB-CABG, diabetics, non-diabetics, either on the circumflex and right coronary systems (p<.05). Better mean flow was detected in RA-CABG on the circumflex in the elderly (p=.04) and the young (p=.05).

RA-CABG demonstrated better TTF and GFR results compared to SV-CABG. These data may contribute to explain the survival benefit of arterial revascularization already reported.