High prevalence of silent, severe coronary ischemia in patients with diabetic foot ulcers

Limited research has been conducted on the extent of coronary artery disease (CAD) in patients with diabetic foot ulcer (DFU). We hypothesize that coronary computed tomography angiography (cCTA) and computed tomography-derived fractional flow reserve (FFR_CT) scans will demonstrate the occurrence of CAD in patients with DFU.

Patients with DFU seen at our institution between June 2022 and July 2024 who underwent cCTA were included. Exclusion criteria were a known history of CAD, prior coronary interventions, or angina. Severe lesion specific ischemia was defined as FFR_CT ≤0.75 distal to a >30% coronary stenosis. Potentially significant ischemia was defined as FFR_CT ≤0.80 distal to a >30% coronary stenosis. The primary outcome was the presence and extent of CAD.

Thirty-three patients met inclusion criteria. Six patients (18.2%) died before obtaining cCTA, four (12.1%) from a major adverse cardiac event. One patient suffered a myocardial infarction and had a lifesaving coronary artery bypass grafting prior to their cCTA. Another patient did not have a cCTA done due to his chronic kidney disease. Four patients (15.2%) had cCTA but did not undergo FFR_CT due to minimal or mild CAD. Results were based on 25 patients who received cCTA. Fifteen (60%) had FFR_CT ≤0.80, with 13 (52%) having FFR_CT ≤0.75 (seven with multi-vessel severe CAD and six with single-vessel severe CAD). Severe disease in the left main and proximal left anterior descending was found in three patients (12%). Six patients (24%) had diffuse atherosclerosis that was not potentially significant. Six patients (24%) underwent cardiac catheterization, with four requiring coronary intervention.

Given the high prevalence of silent severe CAD (proximal or multivessel) in patients with DFU, we recommend that all patients be evaluated with a cCTA with FFR_CT when appropriate.