How decisive is the number of distal arterial anastomoses in coronary bypass surgery?

The benefit of arterial revascularization in coronary surgery remains controversial. The incremental value of additional grafts to the left internal thoracic artery (ITA) has been mainly assessed according to the number of arterial grafts, possibly limiting the detection of its actual impact. We analyzed the influence of the number of distal arterial anastomoses (DAA) performed on late mortality in patients having received from one to three arterial grafts.

Retrospective review of 3685 primary isolated coronary artery bypass grafting (CABG) performed from 1989 to 2014 was conducted with a 13-year mean follow-up. One arterial graft (SITA) was used in 969 patients, two arterial grafts, ITA or gastroepiploic artery (GEA), in 1883 patients (BITA: 1644; SITA+GEA: 239), and three arterial grafts in 833 patients (BITA+GEA). Totally, 795 patients (22%) received one DAA, 1142 patients (31%) two, 1337 patients (36%) three, and 411 patients (11%) four or more. A sub-group analysis was done in the 2104 patients with 3-vessel disease who received at least 2 arterial grafts.

In this series the early mortality was 1.6% and it was not influenced by the surgical technique. Late mortality was significantly influenced by age, gender, heart failure, LV ejection fraction, diabetes status, complete revascularization, number of arterial grafts, number of DAA, both ITA, sequential ITA graft, GEA graft. In multivariable analysis with Cox regression model, the number of DAA was the only technical significant independent prognosis factor of late survival (p < 0.0001), predominant over both ITA, complete revascularization and number of arterial grafts. The impact of the number of DAA on survival was found discriminant from 1 to 3; after 3 there was no more additional effect. In 3-vessel disease patients who received at least 2 arterial grafts, the number of DAA remained a significant independent prognosis factor of late survival (p < 0.0001).

The number of distal arterial anastomoses is an independent predictor of long-term survival, predominant over the number of arterial grafts and the completeness of the revascularization; higher the number, better the late survival. It is a strong support of the extensive use of arterial grafting in CABG.