Study: Mechanical heart valves outperform biological for long-term survival in middle-aged patients

Editor's Note

Patients aged 50 to 70 undergoing heart valve replacement may benefit from mechanical valves over biological ones, according to a new study from the University of Bristol. Healthcare-in-Europe.com reported the news February 13.

As detailed in the article, short-term outcomes between the two options were similar. However, mechanical valves were associated with better long-term survival—especially for patients receiving smaller-sized replacements. These findings challenge the increasing preference for biological valves in this age group and suggest the need for a reevaluation of current surgical trends.

The study, published in the European Journal of Cardio-Thoracic Surgery, analyzed data from 1,708 patients treated at the Bristol Heart Institute between 1996 and 2023, the outlet reports. Of these, 69.7% received biological valves, despite existing guidelines recommending mechanical valves for patients under 50 and leaving the choice open for those aged 50 to 70. While no differences were observed in early outcomes, mechanical valve recipients demonstrated a survival advantage up to 13 years post-surgery.

The article also details the critical role of valve size in determining outcomes. Patients with a 19 mm biological valve—commonly used in females—had the poorest long-term survival, while those with a 21 mm mechanical valve fared better than recipients of both 19 mm and 21 mm biological valves. Severe patient-prosthesis mismatch (PPM) was confirmed as a major risk factor for poor outcomes.

Lead researcher Gianni Angelini, BHF Professor of Cardiac Surgery, emphasizes in the article that the study’s findings should prompt a reassessment of the growing preference for biological valves in middle-aged patients. The data suggest mechanical valves provide a significant long-term survival benefit, particularly for smaller valve sizes, despite the requirement for lifelong anticoagulation therapy.

Limitations reportedly include the study’s single-institution design, retrospective data collection, and lack of randomization, which could introduce bias. Nonetheless, researchers argue the findings provide strong evidence that mechanical valves may offer superior long-term outcomes for many patients in this age group.