Flexibility for clinicians in managing RAS inhibitors in noncardiac surgery

Editor's Note

A new study, the Stop-or-Not Trial, has found no significant difference in outcomes for patients undergoing noncardiac surgery who either continued or discontinued their renin-angiotensin system (RAS) inhibitor therapy, MedPage Today August 31 reports. The randomized clinical trial, which included over 2,200 patients, reported the rate of death and major complications at 28 days postoperatively was 22% for both groups (RR 1.02, 95% CI 0.87-1.19). This finding suggests that either strategy may be acceptable, allowing clinicians more flexibility based on individual patient needs and the specifics of the surgical procedure.

The study, presented at the European Society of Cardiology (ESC) meeting and published in JAMA Network, involved patients who had been on RAS inhibitors for at least 3 months before surgery. These medications, including angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs), are commonly prescribed for hypertension and heart failure.

Matthieu Legrand, MD, PhD, lead researcher from the University of California, San Francisco, highlighted during the ESC meeting the findings could simplify decision-making for clinicians. He noted that most patients could safely continue or withhold RAS inhibitors during the perioperative period, depending on their medical history and surgical circumstances. However, he also mentioned that patients with a high risk of hypotension, bleeding, or those undergoing complex surgery might benefit from discontinuing these medications.

While the trial indicated a slightly higher incidence of intraoperative hypotension (54% vs 41%) among those who continued RAS inhibitors, this did not lead to an increase in serious postoperative complications such as cardiovascular events or acute kidney injury. The authors suggest this may be due to the rapid correction of blood pressure during surgery.

Despite the study's findings, American and European guidelines remain cautious, suggesting the decision to continue or discontinue RAS inhibitors should be individualized. Philip Devereaux, MD, PhD, a discussant at the ESC meeting, emphasized the importance of considering perioperative hemodynamics, particularly for patients with pre-existing hypertension or hypotension. Some limitations of the study, such as the lack of blinding and its focus on a single country, suggest that more data are needed to guide perioperative management of RAS inhibitors more broadly.