The effect of sequential versus single vein aortocoronary bypass surgery on resting left ventricular function.

To study the effectiveness of sequential vein grafts in coronary bypass surgery, left ventricular (LV) function was serially estimated in 28 patients with sequential grafts and compared with that in 24 patients with multiple single vein grafts. Early patency of sequential grafts was 98% vs. 94% for single veins. Late patency (mean 28 months after operation) of sequential veins was 97% vs. 85% for single vein grafts (mean 32 months after operation). Various parameters of resting LV function (pressure, volumes, ejection fraction, regional contraction score, mean velocity of fiber shortening) showed only slight and non-significant changes during the angiographic follow-up in the sequential vein graft group, with the exception of LVEDP, which was significantly lower at the late follow-up (p less than 0.05). There was an apparently spurious highly significant decline in fiber shortening velocity in the sequential graft group (p less than 0.001). Division of the series into subgroups of complete or incomplete revascularization did not improve the predictive power of resting LV function. The data reveal that sequential vein grafts are comparable to multiple single vein grafts as far as the influence on LV function at rest is concerned.