Should mitral valve replacement age guidelines be lowered due to better bioprosthetic mitral valve durability?

Objective: Guideline recommendations for mechanical or bioprosthetic valve for mitral valve replacement by age remains controversial. We sought to determine bovine pericardial valve durability by age and risk of reintervention.

Methods: This retrospective study between 2 large university-based cardiac surgery programs examined patients who underwent bioprosthetic mitral valve replacement from 2004 to 2020. Follow-up was obtained through June 2022. Durability outcomes involving structural valve deterioration were compared by age decile.

Results: Of 1544 available patients, mean age was 66 ± 13 years and 652 (42%) were aged less than 65 years. Indications for mitral valve replacement were as follows: mitral regurgitation greater than 2+ in 53% (n = 813), mitral stenosis in 44% (n = 650), endocarditis in 18% (n = 277), and reoperation in 39% (n = 602). Concomitant procedures were aortic valve replacement in 28% (n = 426), tricuspid valve in 36% (n = 550), and coronary artery bypass in 19% (n = 290). Thirty-day mortality was 5.4%. In follow-up (clinical: median [interquartile range] 75 [25-129] months), reoperation for endocarditis and new stroke were low (0.30 and 1.06 per 100 patient/years, respectively). The cumulative incidence of mitral valve reintervention for structural valve deterioration among all patients was 6.2% at 10 years and 9.0% at 12 years with no statistical difference in structural valve deterioration in patients aged 40 to 70 years (P = .1). In 90 patients with mitral valve reintervention, 30-day mortality after reintervention was 4.7% (n = 2) for 43 with mitral valve-in-valve and 6.4% (n = 3) for 47 with reoperation.

Conclusions: Bovine pericardial mitral valve replacement is a durable option for younger patients. The opportunity to avoid anticoagulation and the associated risks with mechanical mitral valve replacement may be of benefit to patients. These insights may provide data needed to revise the current guidelines.