Objective: To compare results of aortic valve replacement in patients with normal annulus and in those undergoing anterior and posterior enlargement of a small annulus to implant a larger prosthesis.
Methods: The study included 22 patients with enlargement of a small aortic annulus and 23 with a normal aortic annulus, with similar demographic characteristics and selected from a large surgical population. For normal annulus, simple valve replacement was performed. For annular enlargement, the posterior approach required incision in the mid portion of the non-coronary sinus, up to the anterior mitral leaflet; anterior enlargement was achieved by an incision between the left and right coronary ostium, extended to the ventricular septum for 2 cm. The aorta was reconstructed with bovine pericardium patches. The results analyzed included diameter of aortic annulus at surgery, clinical evolution (2 to 11 years of follow-up), left outflow tract obstruction and left ventricular mass (by Doppler echocardiography).
Results: Enlargement increased the aortic annulus from 18.3 +/- 2.2 mm to 24.8 +/- 2.0 mm (p < 0.001), a value similar to aortic annulus considered normal: 24.9 +/- 1.5 mm (NS). For annular enlargement, the peak systolic gradient at the prosthesis decreased from 83.6 +/- 22.3 mmHg (preoperative) to 26.7 +/- 11.4 mmHg (p < 0.01) at the last evaluation. For normal annulus, a reduction from 68.2 +/- 28.7 mmHg to 32.8 +/- 16.2 mmHg occurred (p < 0.001) (final values similar between groups; NS). Left ventricular mass at the last evaluation was 147.2 +/- 45.9 for patients with enlargement and 148.1 +/- 70.4 for those with normal annulus.
Conclusion: Anterior and posterior aortic annulus enlargement enabled increases in annular diameter and valve prosthesis size, providing clinical and echocardiographic results similar to patients with valve replacement in a normal annulus.