Decision-making for patients with patent left internal thoracic artery grafts to left anterior descending.

BACKGROUND

It is unknown whether coronary reintervention confers a survival advantage when a previously placed left internal thoracic artery graft to the left anterior descending coronary artery (LAD) is patent. We compared survival after medical therapy, percutaneous intervention, and reoperative coronary artery bypass grafting in such patients who developed non-LAD territory jeopardy.

METHODS

From 1971 to 2000, 4,640 patients with prior coronary artery bypass grafting that included left internal thoracic artery to LAD grafting were found on angiography during active follow-up to have a patent left internal thoracic artery to LAD graft, but at least 50% stenosis of non-LAD territories or grafts to them. Two survival analyses were performed: (1) intent-to-treat, which included patients undergoing reoperative coronary artery bypass grafting (n = 731) or percutaneous intervention (n = 994) within 6 weeks of angiography or medical management (n = 2,782), and (2) competing risk/crossover, in which patients were classified as medically managed until crossover to coronary artery bypass grafting or percutaneous intervention.

RESULTS

In the intent-to-treat analysis, propensity-adjusted early (<1 year) survival was similar for all patients, but late survival was slightly better after percutaneous intervention than with medical management (p < or = 0.05). In the competing risk/crossover analysis, adjusted survival was best for medically treated patients early; however, late survival was similar among all three groups.

CONCLUSIONS

Patients with patent left internal thoracic artery to LAD grafts who develop non-LAD territory jeopardy derive no survival benefit from reintervention, consistent with previous observations that for coronary reintervention to improve survival, the LAD territory must be jeopardized. Reintervention in patients with a patent left internal thoracic artery to LAD graft may be warranted to relieve symptoms, without expecting a survival benefit.