Accelerated Degeneration of a Bovine Pericardial Bioprosthetic Aortic Valve in Children and Young Adults
Background—Experience with aortic valve replacement (AVR) using current-generation pericardial bioprostheses in young patients is limited. The death of a child with accelerated bioprosthetic aortic stenosis prompted enhanced surveillance of all such patients at our institution.
Methods and Results—We reviewed records of 27 patients who had undergone AVR (median follow-up 13.7 months) with a bovine pericardial bioprosthesis at age ≤30 years. In the Mitroflow® LXA valve group (n=15), freedom from valve failure was 100% at 1 year, 53% (95% confidence interval [CI] 12-82%) at 2 years, and 18% (CI 1-53%) at 3 years. No Magna®/Magna Ease® valves (n=12) failed by 3 years. Among valve failure patients, median age at AVR was 12 years (range 10-21 years). Life-threatening prosthetic aortic stenosis was detected at a median of 6 months following prior echocardiograms showing ≤ mild gradients. Patients with Mitroflow® LXA compared to Magna®/Magna Ease® valves were smaller (median BSA 1.42 vs. 1.93, p=0.002) and younger (median 13.0 vs. 20.9 years, p=0.02) at AVR. Pathology demonstrated diffuse intrinsic leaflet calcification, unassociated with inflammation or infection, and virtually immobile leaflets in closed position.
Conclusions—Young patients undergoing AVR with Mitroflow® LXA pericardial valves are at high risk for rapid progression from ≤ mild to severe aortic stenosis over months, highlighting their need for heightened echocardiographic surveillance and suggesting that this aortic bioprosthesis should not be implanted in the young. Current data are insufficient to assess the safety of AVR with other pericardial bioprostheses in children and the youngest adults.
- Received March 3, 2014.
- Revision received April 4, 2014.
- Accepted April 15, 2014.