Cardiac Evaluation of Patients with Diabetes Mellitus Before Noncardiac Surgery

Up to 40% of patients undergoing elective surgeries have underlying diabetes mellitus (DM), and therefore an elevated risk of perioperative adverse cardiovascular outcomes. Preoperative cardiovascular risk assessment and therapeutic optimization are warranted in all patients with DM. This is an updated review on preoperative evaluation of cardiac risk in patients with DM undergoing surgery and strategies to minimize the risk. This article summarizes the current evidence and recommendations for cardiac evaluation in DM before noncardiac surgery. Preoperative risk estimation includes risk stratification of the proposed surgery and estimating the risk in the patient using available risk calculators such as the Revised Cardiac Risk Index and assessment of the functional status of the patient in terms of metabolic equivalents of tasks. Preoperative cardiac investigations such as electrocardiogram, echocardiography, stress testing, or cardiac biomarkers should be done in high-risk surgeries, and in certain subsets of patients undergoing low- or intermediate-risk surgeries. Additional testing and preoperative optimization are warranted in patients with heart failure and reduced or preserved ejection fraction, those with cardiac autonomic neuropathy, hypertension with or without end-organ damage, and patients undergoing transplant surgery, all of which are discussed in the current review.