Aortic valve replacement with the freestyle stentless bioprosthesis with respect to spacial orientation of patient coronary ostia

Abstract

Objective: This study evaluates our results for safety and efficacy of aortic valve replacement using the Freestyle bioprosthesis (Medtronic, Inc, Minneapolis, Minn) with a new modified subcoronary implantation technique. This technique takes into account the spacial orientation of the stentless bioprosthesis in the aortic root with respect to the patient’s coronary ostia rather than the native commissures. Methods: Fifty-two consecutive patients with predominant aortic valve stenosis underwent aortic valve replacement with a Freestyle bioprosthesis by means of the described modified subcoronary technique over a 15-month period. Fifty of them were followed up by means of echocardiography at discharge, 6 months, and 1 year. There were 19 men and 31 women, with a mean age of 76 ± 7 years (range, 58-87 years). Valve size ranged from 21 to 27 mm. Results: Patients with bicuspid aortic valves had a significantly larger angle between both coronary ostia than patients with tricuspid aortic valves ( P = .0001). The peak and mean systolic gradients decreased significantly during the first postoperative year for each valve size ( P ≤ .001), and the effective valve areas increased significantly during this time interval for each valve size ( P ≤ .01). Only 13 patients had aortic insufficiency at discharge, which was trivial in 9 and mild in 4 patients. The prevalence of trivial aortic insufficiency decreased during the first postoperative year, and that of mild aortic insufficiency remained unchanged. The sinotubular junction diameter was significantly greater than that of the aortic anulus for each valve size before operation ( P < .001). The sinotubular junction diameter decreased significantly after aortic valve replacement and remained unchanged during the first postoperative year for each valve size ( P < .001). Conclusions: Aortic valve replacement with the Freestyle bioprosthesis using the modified subcoronary technique, which takes into account the spacial orientation of the patient’s coronary ostia, has hemodynamic results similar to those of other series with different subcoronary implantation techniques. This technique is reproducible, safe at the coronary ostial level, and effective in accommodating variability in angles between human coronary ostia, ranging from 130° to 170°. Moreover, the great preoperative discrepancies between aortic anulus and sinotubular junction diameters are corrected immediately after operation. (J Thorac Cardiovasc Surg 2000;119:1185-93)