The "T-MIDCAB" procedure. Use of extension grafts from the undisturbed internal mammary artery in high-risk patients.

BACKGROUND

Minimally invasive direct coronary artery bypass grafting (MIDCAB) is an attractive new alternative for revascularizing patients with high perioperative risk for standard coronary surgery. However, limited surgical exposure through a small thoracotomy makes harvesting the full length of the internal mammary artery (IMA) very difficult and time consuming. We are now employing a new alternative with a "T" shaped bridge graft constructed from the undisturbed IMA using a 4 centimeter interposition segment of donor vessel. We prefer this approach in high risk cases in order to reduce the trauma of the thoracotomy, minimize pain and narcotic use, promote early extubation, and achieve immediate post-operative mobilization and recovery in patients who would otherwise be at risk for a poor outcome with conventional grafting techniques.

METHODS

From September 10, 1997 to December 19, 1997 eight high-risk patients underwent at least one "T-MIDCAB" graft from the undisturbed IMA to the coronary artery using a short segment of either radial artery or saphenous vein. All cases were performed using a limited access anterior thoracotomy through the bed of the resected costal cartilage and without intercostal retraction. Five males and three females ranging from 58 to 83 years (average 73 years) were operated using this new concept. Pre-operative ejection fractions ranged from 25% to 80% (mean 43%). Parsonnet scores ranged from 21 to 43 (average 34) with predicted mortalities ranging from 30 to 40%.

RESULTS

Eleven "T" grafts were placed (1.38 distals/patient). All 8 patients survived. Postoperative complications were minimal. The average length of stay was only 8 days (range 3 to 9 days). Intensive care unit stay averaged 3 days (range 1 to 4 days). One patient underwent postoperative angiography which demonstrated full patency of the conduit and all anastomoses.

CONCLUSIONS

"T-MIDCAB" using a bridge graft of free radial artery or saphenous vein appears to be successful in high risk patients. The authors noted shorter operative times, reduced chest wall trauma and better pain control than with standard MIDCAB and full IMA harvesting. Cautious use of this procedure as an alternative to more morbid types of surgical revascularization is advised.