NT-proBNP levels fail to predict risk of CV events after noncardiac surgery: JAMA

A cohort study of over 3000 patients with elevated cardiovascular (CV) risk undergoing noncardiac surgery yielded no conclusive evidence of a difference between an N-terminal pro–B-type natriuretic peptide (NT-proBNP)-based and a self-reported functional capacity-based estimate of major adverse cardiac events (MACE) risk.

Nearly 16 million surgical procedures are performed yearly in North America, and postoperative CV events are frequent. Guidelines suggest functional capacity or BNP to guide perioperative management. Data comparing the performance of these approaches are inadequate. To fill this knowledge gap, Giovanna Lurati Buse, Heinrich Heine University, Düsseldorf, Germany, and colleagues aimed to compare the addition of either NT-proBNP or self-reported functional capacity to clinical scores to estimate MACE risk in a cohort study.

MACE was defined as a composite endpoint of in-hospital cardiovascular mortality, myocardial infarction, cardiac arrest, stroke, and congestive heart failure requiring transfer to a higher unit of care.

The study included patients undergoing elective, inpatient, and noncardiac surgery at 25 tertiary care hospitals in Europe between 2017 and 2020. Eligible patients were either aged 45 years or older with a National Surgical Quality Improvement Program, Risk Calculator for Myocardial Infarction and Cardiac (NSQIP MICA) above 1%, Revised Cardiac Risk Index (RCRI) of 2 or higher, or they were aged 65 years or older and underwent intermediate or high-risk procedures.

The exposures were preoperative NT-proBNP and the following self-reported measures of functional capacity: (1) questionnaire-estimated metabolic equivalents (METs), (2) ability to climb 1 floor, and (3) level of regular physical activity.

Based on the study, the researchers reported the following findings:

• A total of 3731 eligible patients undergoing noncardiac surgery were analyzed; 3597 patients had complete data (35.0% were women; 1463 were aged 75 years or older; 86 experienced a MACE).
• Discrimination of NT-proBNP or functional capacity measures added to clinical scores did not significantly differ (Area under the receiver operating curve: RCRI, age, and 4MET, 0.704; RCRI, age, and 4MET plus floor climbing, 0.702; RCRI, age, and 4MET plus physical activity, 0.724; RCRI, age, and 4MET plus NT-proBNP, 0.736).
• Benefit analysis favoured NT-proBNP at a threshold of 5% or below, i.e. if true positives were valued 20 times or more compared with false positives. The findings were similar for NSQIP MICA as baseline clinical scores.

"Our findings suggest that caution about the clinical applicability of an NT-proBNP–based preoperative assessment is warranted," the researchers concluded.

Reference:

Lurati Buse G, Larmann J, Gillmann H, et al. NT-proBNP or Self-Reported Functional Capacity in Estimating Risk of Cardiovascular Events After Noncardiac Surgery. JAMA Netw Open. 2023;6(11):e2342527. doi:10.1001/jamanetworkopen.2023.42527