Role of B-mode venous mapping in infrainguinal in situ vein-arterial bypasses.

Two hundred and eighty patients underwent B-mode mapping (B-map) of their saphenous vein over a period of 3 years (1984-1987) before lower limb revascularization. B-map deemed that 229 veins were suitable for bypass, 26 were questionable and 25 were unsuitable. A successful bypass was achieved in 97.8 per cent of the suitable group (all in situ), 85 per cent of the questionable group (in situ and composite vein), and 80 per cent of the unsuitable group (composite vein). At a minimum follow-up period of 1 year the overall patency rate was 95.0 per cent with a revision rate of 15.8 per cent. There was no correlation between revision rate and vein complexity or calf vein diameter. Calf vein diameter greater than 2.5 mm was correlated with a successful bypass (P less than 0.001). It is concluded that B-map is the investigation of choice for saphenous vein assessment before infrainguinal bypass surgery.