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Propensity matched long-term analysis of mechanical versus stentless aortic valve replacement in the younger patient.

OBJECTIVES
The choice of prosthesis for aortic valve replacement (AVR) in younger patients remains controversial. Stentless AVR was introduced 3 decades ago, with the aim of better haemodynamics and durability than stented xenografts. The objective of this analysis was to compare the long-term outcomes to mechanical prostheses in younger patients (age ≤60 years).


METHODS
All adult patients who underwent AVR due to aortic valve stenosis and/or insufficiency between 1993 and 2002 were identified. After the exclusion of patients with congenital heart defects, aortic dissections and Ross-procedures, 158 patients with stentless valves and 226 patients with bi-leaflet mechanical valves were finally included in this analysis. Sixty-six patient pairs could be included in a propensity matched analysis. Mortality and morbidity including stroke, bleeding, endocarditis and reoperation were analysed.


RESULTS
Group baseline characteristics and operative data did not differ significantly after propensity matching. Hospital mortality was 0.0% in the stentless and 1.5% in the mechanical group. Total patient years/median follow-up was 2029.1/15.4 years (completeness: 100.0%, range: 0-25 years). After 20 years, actuarial survival was 47.0 ± 6.4% in the stentless and 53.3 ± 6.6% in mechanical group (P = 0.69). Bleeding, endocarditis and stroke occurred rarely and did not differ significantly between groups. After 20 years, actuarial overall freedom-from-reoperation was 45.1 ± 8.2% in the stentless group and 90.4 ± 4.1% in the mechanical group (P < 0.001). Hospital mortality while reoperation was 7.4% in the stentless group and 0% in the mechanical group (P = 1.0).


CONCLUSIONS
Long-term morbidity and mortality of stentless and mechanical aortic valves were statistically not different besides a significantly higher reoperation rate after stentless AVR combined with a probably higher risk of in-hospital mortality. Thus, mechanical AVR should remain the procedure of choice in younger patients.