Newly published findings are questioning physicians’ enthusiasm for early aortic valve replacement (AVR) in patients with asymptomatic severe aortic stenosis (AS). Led by Sanjay Kaul, MD, from Cedars-Sinai Medical Center in Los Angeles, the review gathered findings from four key trials that did not support endorsing early AVR, especially transcatheter AVR (TAVR), as the preferred therapy for low-risk patients with asymptomatic severe AS. “Expanding early or preemptive interventional treatment to all asymptomatic patients who might formally meet hemodynamic and anatomical criteria may be premature. For now, awaiting symptoms remains a justifiable strategy,” said Kaul, referencing a recent NEJM editorial. Comparing trial outcomes The review, which appears in the April 15 issue of the Journal of the American College of Cardiology, compared trial outcomes where asymptomatic patients with severe AS were enrolled under criteria ranging from stress test responses to biomarker elevations and evidence of myocardial fibrosis. Of note were two trials assessing surgical AVR (SAVR), with one focused only on TAVR and the other included a blend of both approaches. Kaul highlighted that patient ages, sample sizes, and the time to intervention also differed widely among the studies. One major observation was the discrepancy in conversion rates to AVR in the clinical surveillance (CS) arm. In some trials, nearly half of the CS patients required conversion within the first year, a figure that sharply contrasts with the natural history of asymptomatic severe AS, where about 20% of patients are expected to convert annually. Impact less clear In addition, while early intervention groups showed a reduction in unplanned cardiovascular hospitalizations and stroke in several studies, the impact on all-cause and cardiovascular mortality was less clear. Only the SAVR trials demonstrated a mortality benefit, and even then, the number of events was relatively small. “…the quality and the quantity of evidence is not sufficient to justify a Class I guideline recommendation,” said Kaul. “Compared with SAVR trials, it might have been more difficult to show a mortality difference in EARLY TAVR because the CS patients crossed over much sooner and to a greater extent than in the SAVR trials.” Definitive evidence required In conclusion, Kaul commented that the current strategy of clinical surveillance with delayed AVR remained justifiable until more definitive evidence emerged. He added that the quantum of evidence required for upgrading guideline recommendations for early TAVR in these patients should ideally be based on stringent trial design using unbiased primary endpoints and longer follow-up ideally using placebo control. Until then, he said, the current guidelines need not necessarily change. Sources: Kaul S. Aortic Valve Replacement for Asymptomatic Severe Aortic Stenosis: Is Enthusiasm Exceeding the Evidence? J Am Coll Cardiol. 2025;85:1511–1514. Image Credit: rocketclips – stock.adobe.com