Bilateral versus unilateral internal mammary revascularization in patients with diabetes

Area of Science:

• Cardiovascular Surgery
• Diabetology
• Thoracic Surgery

Background:

• Coronary artery bypass grafting (CABG) is a common procedure for multivessel disease.
• The use of internal mammary artery (IMA) grafts is standard practice.
• The benefit of bilateral IMA (BIMA) grafts in diabetic patients remains a subject of investigation.

Purpose of the Study:

• To evaluate the efficacy of BIMA grafts compared to single IMA (SIMA) grafts in diabetic patients undergoing CABG.
• To assess early and long-term outcomes, including graft patency and survival rates.
• To determine if ejection fraction influences the benefit of BIMA grafts.

Main Methods:

• Historical cohort study of 1131 patients undergoing isolated, primary, multiple CABG with skeletonized IMA grafts.
• Comparison between diabetic patients receiving SIMA (n=277) and BIMA (n=190) grafts.
• Median follow-up of 8.1 years, analyzing graft patency, hospital mortality, and long-term survival.

Main Results:

• Early graft patency was significantly higher with BIMA (97.7%) versus SIMA (93.8%).
• No significant difference in overall survival rates between SIMA and BIMA groups.
• In patients with preserved ejection fraction, BIMA use was associated with significantly higher 10-year survival and improved freedom from adverse cardiac events.

Conclusions:

• Skeletonized BIMA grafts offer significant benefits in coronary revascularization for diabetic patients with preserved ejection fraction.
• The survival benefit of BIMA grafts is limited in diabetic patients with reduced ejection fraction due to higher cardiac mortality.
• BIMA grafting should be considered in selected diabetic patients to improve long-term outcomes.