Noncardiac surgery is a major stressor to the cardiovascular system, increasing risks for myocardial infarction, heart failure and arrhythmias among other effects, according to a presentation at the 2025 annual Perioperative Medicine Summit. Clinicians can use the most recent guidelines for perioperative cardiovascular management for noncardiac surgery to determine when to proceed with surgery or pause for further evaluation (Circulation 2024;150[19]:e351-e442).

About 1 in 33 noncardiac surgical hospitalizations are associated with major adverse cardiovascular events (JAMACardiol 2017;2[2]:181-187), said Nathaniel Smilowitz, MD, a co-author of the guidelines and an interventional cardiologist at NYU Langone Health, in New York City.

“We want to make sure we’re not missing severe left main or three-vessel coronary artery disease,” he said. “We also want to make sure we’re not missing severe aortic stenosis, severely reduced left ventricular ejection fractions and other high-risk cardiovascular disease prior to surgery.”

Patients who need emergency surgery should proceed, Smilowitz said, while management of those who have known cardiovascular conditions, such as heart failure or unstable arrhythmias, should be done by a multidisciplinary team.

To estimate perioperative risk in patients without known heart disease, it is recommended using a validated risk calculator, such as the Revised Cardiac Risk Index (RCRI) or Universal NSQIP Perioperative MI and Cardiac Arrest Risk Calculator.

Next, according to Smilowitz, consider any risk modifiers that would not be detected by calculators, including severe valvular heart disease, severe pulmonary hypertension, elevated-risk congenital heart disease, prior coronary stents or bypass surgery, recent stroke, pacemaker or frailty.

“It doesn’t mean that if you have these things, you are necessarily high risk,” he said, “but it does require you to think about that patient differently than somebody who has no cardiac history.” A person with a pacemaker “may do perfectly well” in the OR, but you may need to change the device settings ahead of time.

If the patient has a low calculated risk and no risk modifiers, they can proceed to the OR, Smilowitz said. However, if there is an elevated cardiac risk or at least one risk modifier, additional follow-up is needed. For elevated calculated risk and no modifiers, optimize medical therapy and consider a 12-lead ECG. If there is a risk modifier present with any calculated risk, bring other experts, such as a neurologist or cardiologist, into the discussions around perioperative risk stratification and consider a 12-lead ECG or echocardiography, particularly for patients with suspected valvular heart disease, as well as medical management for underlying cardiovascular conditions.

For elevated-risk surgery in a patient with known coronary or cerebrovascular disease, perform an ECG prior to surgery, Smilowitz said. This may identify acute cardiac conditions, but it is important to establish a baseline so if someone has an issue postoperatively, changes in the ECG can be easily identified. Any new abnormalities like ST changes or new Q waves found preoperatively should be factored into the decision to proceed to surgery.

If the patient has new dyspnea, physical exam findings of heart failure, or suspected or new/worsening left ventricular dysfunction, see if they have a heart failure diagnosis, he said. If they don’t, get an echocardiogram to guide perioperative management. If they do, get a repeat echo to see if anything has changed since their previous test.

From there, assess the patient’s functional capacity. Beyond asking about climbing two flights of stairs to estimate four minutes of exercise tolerance (METs) and moving them on to the OR, look to other measures. The Duke Activity Status Index (DASI) is an easy questionnaire patients can complete that asks about activities from gardening to running. Studies have found DASI scores of at least 34 to be associated with reduced odds of 30-day death or myocardial infarction following noncardiac surgery (Lancet 2018;391[10140]:2631-2640).

Biomarkers such as troponin and BNP/NT-proBNP also can be used to determine fitness for surgery, Smilowitz said. If findings are abnormal, multidisciplinary team discussion regarding the risks and benefits of additional cardiac evaluation should be considered.

Stress testing may be considered to evaluate for inducible myocardial ischemia in selected patients: those undergoing elevated-risk, noncardiac surgery with poor or unknown functional capacity, elevated cardiac biomarkers, and elevated risk for perioperative cardiovascular events.

Coronary calcium scores from existing, non-gated chest CT scans in patient electronic health records could be factored into predicting perioperative risk for adverse outcomes, Smilowitz said. A study that he coauthored found that the risk for perioperative death or myocardial infarction was substantially higher in patients who had coronary calcium versus no coronary calcium, and adding that to RCRI can help refine risk prediction (Circulation 2023;148[15]:1154-1164).

There is no benefit from routine, preoperative invasive coronary angiography, he said, and data are insufficient that the test improves long-term postoperative outcomes. However, it remains indicated for selected conditions: acute coronary syndromes, angina despite maximal medical therapy, moderate to severe ischemia, suspected left main disease and cardiomyopathy. Preoperative coronary revascularization generally is not recommended except for patients with left main coronary artery disease and those with acute coronary syndromes being considered for elective noncardiac surgery, who should be treated for their acute cardiac condition while deferring surgery.

Overall, Smilowitz said, the guidelines are just recommendations and can’t replace clinical judgment. “Look at the patient in front of you and listen to what they’re telling you when you make decisions about cardiovascular testing.”

Smilowitz’s work “has been incredibly impactful in the perioperative field and having him at the summit was a huge win for us,” commented anesthesiologist Angela Selzer, MD, the medical director of pre-procedure services at the University of Colorado Hospital, in Aurora, who moderated the session. “His research has informed our ability to appropriately risk-stratify the patients we see in our preoperative clinics every day.”

By Karen Blum

Selzer reported no relevant financial disclosures. Smilowitz reported service on an advisory board and is a consultant to Abbott Vascular.