Porcine or human stentless valves for aortic valve replacement? Results of a 10-year comparative study

Stentless porcine valves in the aortic position exhibit similar excellent hemodynamic performance to homografts, but have the advantage of availability. Their performance was compared over a 10-year period in a single-surgeon and single-institution series.

Demographic, operative and mortality data were obtained retrospectively. Survivors were interviewed by telephone according to a defined protocol. Definitions and analyses were in accordance with joint STS/AATS guidelines.

A total of 408 stentless porcine and homograft aortic valve replacements (AVR) was performed between 1991 and 2001. Five patients were excluded due to incomplete data, in addition to 82 patients who underwent AVR with a free-standing root replacement technique. Hence, 321 patients (217 males, 104 females; mean age 67 +/- 12 years) had a subcoronary implant. The median time to follow up was 4.9 years (range: 2.9-6.6 years). No differences were noted between homograft and stentless porcine valves in one- and five-year freedom from structural valve deterioration (99.1 versus 97.2% and 95.7 versus 93.1%; p = 0.10), reoperation (99.2 versus 99.4% and 97.8 versus 96.7%; p = 0.45) and endocarditis (98.3 versus 99.4% and 97.4 versus 99.4%; p = 0.14). Overall one- and five-year survival comparing homograft to stentless porcine valve was 90.4 versus 92.3% and 80.8 versus 73.7%, respectively; p = 0.23. Independent predictors of mortality on multivariate analysis were: ventricular function (p < 0.0001), increasing age (p < 0.001), increasing serum creatinine (p < 0.001) and concomitant coronary surgery (p = 0.05). Treated hypercholesterolemia was independently protective against mortality, with an odds ratio of 0.26 (CI 0.10 to 0.66; p = 0.005).

The porcine stentless valve, when implanted in the subcoronary position, is an excellent alternative to the homograft and shows excellent clinical performance and durability at mid term.