American Board of Internal Medicine (ABIM) Certification Practice Exam

Which patient demographic is indicated for CABG if they have disease of the left anterior descending artery?

1. Non-diabetic with single vessel disease

2. Diabetic with disease of left anterior descending AND one of the circumflex arteries

3. Non-diabetic with two vessel disease

4. Diabetic with single vessel disease

The correct answer is: Diabetic with disease of left anterior descending AND one of the circumflex arteries

Coronary artery bypass grafting (CABG) is often indicated for patients with significant coronary artery disease, particularly when it involves critical vessels. In the context of left anterior descending artery (LAD) disease, the presence of diabetes mellitus significantly influences surgical decision-making. Patients with diabetes are at higher risk for coronary artery events and typically have worse outcomes if treated with percutaneous interventions alone. When a diabetic patient has significant stenosis involving the left anterior descending artery and also one of the circumflex arteries, this indicates potential multi-vessel disease that requires more extensive revascularization to improve both survival and quality of life. CABG can offer better long-term outcomes in such populations, particularly in diabetic patients with coronary artery disease. In contrast, non-diabetic patients or those with single-vessel disease may not necessarily require CABG, especially if the left anterior descending artery is the only affected vessel, as many of these patients can be managed effectively with medical therapy or percutaneous interventions. Therefore, option B correctly identifies a demographic that should be evaluated for CABG due to the higher risk associated with diabetes and the multi-vessel involvement1.