Stentless bioprostheses for the small aortic root.

摘要: BACKGROUND AND AIMS OF THE STUDY: Despite a variety of different artificial heart valves no ideal prosthesis for the small aortic root is yet available. Conventional stented are hemodynamically disadvantageous because higher transvalvular pressure gradients. Stentless bioprostheses were implanted in such patients to evaluate their performance as an alternative homografts and conventional mechanical prostheses. MATERIALS METHODS: We analyzed 57 with roots who underwent stentless valve replacement (Toronto SPV) from March 1993 November 1995. All but two had stenosis. The mean age at operation was 70.9 (+/-8.2) years. annular diameter 18-23 mm (mean 21.4 +/- 1.1 mm) all patients. Of patients, 17 received 23 40 25 prosthesis. RESULTS: Using oversizing technique, size adjusted according sinotubular junction diameter, allowing gain 2-4 be achieved On pre-discharge echocardiography maximum flow velocity 2.3 0.4 m/s, gradient 19.1 6.8 mmHg, effective orifice area 1.46 0.27 cm2. NYHA class I or II discharge. One patient reoperated due folded annulus caused by too much oversizing. At six months follow up there significant reduction gradients increase areas relation decrease pre-existing left ventricular hypertrophy. CONCLUSIONS: show excellent hemodynamics comparably large internal flexibility. Controlled safe technique without additional complications. As larger sizes can implanted, enlargement not necessary. superior hemodynamic profile especially advantageous roots.