Among patients with a failed mitral bioprosthetic valve, transcatheter mitral valve-in-valve (mVIV) treatment was associated with a lower rate of death or disabling stroke at one year compared with standard repeat mitral valve replacement surgery (rMVR), according to results from the SURVIV study presented during a Late-Breaking Clinical Trial session at ACC.26 in New Orleans.

The investigator-initiated study conducted across seven referral cardiovascular hospitals in Brazil randomized 150 patients (mean age, 58 years; 72% women) with severe symptomatic mitral bioprosthetic valve dysfunction 1:1 to either mVIV or surgical rMVR. All patients were considered suitable candidates for either procedure; about a quarter had already undergone more than one prior mitral valve surgery. About 70% of patients had pulmonary hypertension, 50% had atrial fibrillation and many had rheumatic heart disease.

At one year, the primary endpoint of all-cause death or disabling stroke occurred in 20.8% of patients treated with rMVR group and in 5.3% of those treated with mVIV (hazard ratio, 0.23; p=0.005). This difference was largely driven by events occurring in the early postoperative period.

Looking at secondary endpoints at 30 days, death from cardiovascular causes was higher in the surgical than the mViV group (12.5% vs. 0%). Also occurring more frequently in the two groups, respectively, was acute kidney injury (15.3% vs. 0%; p<0.001) and life-threatening or major bleeding complications (11.1% vs. 1.3%; p=0.016). The rate of stroke was low in the two groups (1.4% vs. 0%).

In terms of valve performance, the mean mitral gradient was 5.9 mm Hg and 5.3 mm Hg in the mViV and surgery groups at three months and 6.7 mm Hg and 5.4 mm Hg (p=0.07) at 12 months. In the two groups respectively, the peak mitral gradient was 12.9 mm Hg and 14.5 mm Hg at three months (p=0.49) and 15.2 mm Hg and 13.9 mm Hg at 12 months, and the mitral valve area was 1.5 and 1.8 (p<0.001) at three months and 1.4 and 1.8 at 12 months (p=0.003).

Substantial improvement in symptoms and quality of life was seen with both procedures.

Among the study limitations is its small size and being conducted in a single country making it less generalizable to other populations and that many patients had rheumatic heart disease and pulmonary hypertension which could increase surgical risk. Although the study was not blinded, there was a blinded independent expert committee that adjudicated patient outcomes.

“These results suggest that a transcatheter valve-in-valve procedure may offer an important short-term clinical benefit in selected high-risk patients,” said principal investigator Dimytri Siqueira, MD, PhD, noting this was the first time outcomes between mVIV and rMVR were compared in a randomized, controlled trial. “However, long-term follow-up of patient outcomes is essential to better understand durability and the overall role of this approach in clinical practice.” The researchers plan to follow the patients in the study for a total of 10 years.

Clinical Topics: Arrhythmias and Clinical EP, Cardiac Surgery, Diabetes and Cardiometabolic Disease, Heart Failure and Cardiomyopathies, Invasive Cardiovascular Angiography and Intervention, Prevention, Pulmonary Hypertension and Venous Thromboembolism, Atrial Fibrillation/Supraventricular Arrhythmias, Cardiac Surgery and Arrhythmias, Cardiac Surgery and Heart Failure, Pulmonary Hypertension, Interventions and Vascular Medicine, Hypertension

Keywords: ACC Annual Scientific Session, ACC26, New Orleans, Atrial Fibrillation, Hypertension, Pulmonary, Transcatheter Aortic Valve Replacement, Mitral Valve, Rheumatic Heart Disease, Acute Kidney Injury, Hemorrhage, Stroke