Mitroflow LXA valves showed a rapid decline in freedom from valve failure to 18% by 3 years in patients ≤30 years, indicating high risk for severe aortic stenosis.
Does the Mitroflow LXA bovine pericardial bioprosthesis compared to Magna/Magna Ease valves increase the risk of rapid valve failure in patients ≤30 years of age undergoing aortic valve replacement?
The Mitroflow LXA bovine pericardial bioprosthesis is associated with rapid, life-threatening structural valve deterioration in children and young adults, indicating it should not be implanted in this population.
Absolute Event Rate: 0% vs 0%
Background— Experience with aortic valve replacement (AVR) with 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 ≤30 years of age. In the Mitroflow LXA valve group (n=15), freedom from valve failure was 100% at 1 year, 53% (95% confidence interval, 12–82) at 2 years, and 18% (95% confidence interval, 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 after prior echocardiograms showing mild or less gradients. Patients with Mitroflow LXA compared with Magna/Magna Ease valves were smaller (median body surface area, 1.42 versus 1.93 m 2 ; P =0.002) and younger (median age, 13.0 versus 20.9 years; P =0.02) at AVR. Pathology demonstrated diffuse intrinsic leaflet calcification, not associated 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 or less 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.
Saleeb et al. (Wed,) reported a other. Mitroflow LXA valves showed a rapid decline in freedom from valve failure to 18% by 3 years in patients ≤30 years, indicating high risk for severe aortic stenosis.