Bilateral internal thoracic artery operations in the elderly

Elderly surgical patients have higher operative morbidity and mortality than younger cohorts, particularly when the procedure is lengthy and complex. While use of bilateral internal thoracic arteries (BITA) is often associated with increased surgical risk, we nevertheless hypothesized that the use of BITA in elderly coronary artery bypass patients would not significantly increase their operative risk beyond that encountered using single internal thoracic arterial (SITA) or saphenous vein grafts (SVG). We maintained that arterial grafts remain essentially unaffected by arteriosclerosis, and that extension of a high-quality life is a desirable outcome regardless of age at operation.

We studied myocardial revascularization in 673 patients over 65 years of age at the time of operation. All operations were conducted or supervised by a single surgeon during a ten-year period from January 1986 to January 1996. Preoperative and operative dates were recorded prospectively.

All patients underwent coronary artery bypass grafting.

The study compared outcomes in patients having all veins, SITA or BITA operations. For the first analysis, 673 patients were divided into three groups: 163 patients (Group 1) had saphenous vein used for all bypasses; 338 patients had a SITA with supplemental vein grafts (Group 2); and 172 patients (Group 3) had BITAs with additional vein grafts as needed. In the second analysis, Group 3 was subdivided and grouped by the coronary arteries which received the ITA grafts, and the analysis was repeated. One hundred and sixteen patients (Group 3A) underwent traditional placement of ITA bypasses (left ITA to the LAD, right ITA to the RCA); in Group 3B, 56 patients received revascularization of branches of the left coronary artery (left ITA to the circumflex system, right ITA to the LAD).

We communicated directly with 90.5% of the patients, their families, or their physicians. The survival status of the remainder was determined through the National Social Security Death Index Network. This allowed us to obtain follow-up longevity data for 100% of the study sample at a mean observation period of 5.03+/-3.1 years with variation between 10.8 years to 2.4 years.

A multivariate analysis showed that placement of both ITA grafts to left-sided arteries in older patients independently improved long-term survival (p=0.031).

The BITA procedure does not have greater operative morbidity or mortality in the elderly despite the length or complexity of the surgery. To realize improved long-term survival rates, however, both ITAs must be grafted to the left coronary artery branches.