Background: The aim of this study was to evaluate early and mid-term improvement in functional capacity and left ventricular mass in young adults following implantation of 19-mm or 21-mm bileaflet mechanical aortic prostheses.

Methods: Fourteen patients (10 males, 4 females; mean age 25±7 years; range 17 to 41 years) underwent isolated aortic valve replacement due to rheumatic aortic valve stenosis. The size of the bileaflet mechanical prostheses was 19 mm in six patients, and 21 mm in eight patients. The mean body surface area was 1.7±0.15 m² (1.58 m² and 1.76 m² for 19- and 21-mm prostheses, respectively). Functional capacity was New York Heart Association (NYHA) class II in 10 patients, and class III in four patients. Implantation was performed without enlargement of the aortic root in all but two patients. At the end of a mean follow-up of 32±11 months (range 12 to 56 months), transvalvular gradients, effective orifice area, and the diameter of the left ventricle were calculated by transthoracic echocardiography in all the patients during rest and after maximal treadmill exercise.

Results: There was no mortality or any postoperative complications. All the patients were in NYHA functional class I at the last follow-up (p=0.01). Compared to preoperative values, significant improvements were observed postoperatively in the mean transvalvular gradient (p=0.005) and left ventricular mass (p=0.01).

Conclusion: Our results suggest that implantation of 19-mm or 21-mm aortic bileaflet mechanical prostheses results in significant symptomatic and functional improvement in young adults, without contributing to mortality and complications.

Keywords : Aortic valve; aortic valve stenosis/surgery; echocardiography, Doppler; heart valve diseases/surgery; heart valve prosthesis; hemodynamic processes; prosthesis design