EVOLVED Evaluates Early Aortic Valve Intervention in Patients With Asymptomatic Severe AS and Myocardial Fibrosis

October 28, 2024—The EVOLVED trial found that early aortic valve intervention in patients with asymptomatic, severe aortic stenosis (AS) and midwall myocardial fibrosis on MRI did not reduce the incidence of the composite primary endpoint of all-cause death or unplanned AS hospitalization compared with guideline-directed conservative management.

The EVOLVED findings were presented at TCT 2024, the 36th annual Transcatheter Cardiovascular Therapeutics annual scientific symposium of the Cardiovascular Research Foundation held October 27-30 in Washington, DC, and simultaneously published by Krithika Loganath, MD, et al online in Journal of the American Medical Association.

According to the TCT press release, the EVOLVED trial was an international, multicenter, prospective, randomized, open-label, blinded-endpoint trial conducted at 24 sites in the United Kingdom and Australia.

As summarized by TCT, patients in the trial were asymptomatic with severe AS (aortic valve peak velocity ≥ 4 m/s, ≥ 3.5 m/s with an indexed aortic valve area < 0.6 cm²/m²). Key exclusion criteria included left ventricular ejection fraction < 50%, concomitant severe aortic or mitral regurgitation, estimated glomerular filtration rate > 30 mL/min/1.73 m², contraindications to MR, and patients deemed unfit for intervention.

A total of 427 participants were screened. Of these, 278 were eligible for cardiac MR. The 224 patients with myocardial fibrosis were randomized to early intervention (n = 113) or guideline-directed conservative management (n = 111). The 49 patients without myocardial fibrosis were entered into an observational registry to maintain blinding. The choice of surgical or transcatheter valve replacement was determined by the local heart valve team.

TCT reported the following findings:

• The median time to intervention was 15 months shorter among patients randomized to valvular intervention.
• The primary endpoint (composite of all-cause death or unplanned AS-related hospitalization) was not met (hazard ratio [HR], 0.79; 95% CI, 0.44-1.43; P = .44).
• The secondary endpoint of all-cause death was also not met (HR, 1.22; 95% CI, 0.59-2.51). However, unplanned AS-related hospitalization was lower in the early intervention group (HR, 0.37; 95% CI, 0.16-0.88).
• New York Heart Association symptom class at 12 months favored the early intervention group (odds ratio, 0.37; 95% CI, 0.20-0.70).

“Although early intervention did not reduce the incidence of the composite primary endpoint of all-cause death or unplanned AS hospitalization, our study did find other benefits,” commented Mark R. Dweck, MD, in the TCT press release. “The principal benefit of early intervention appears to be in the reduction of emergency hospitalization and in preventing the development of limiting symptoms. This appears to be a consistent finding across all the trials to date and an important outcome for patients with this condition.”

Dr. Dweck is Chair of Clinical Cardiology at the University of Edinburgh, British Heart Foundation Senior Clinical Research Fellow, and a consultant cardiologist at the University of Edinburgh in Edinburgh, Scotland.