Color Doppler echocardiographic assessment of Sorin mitral prosthetic valve.
Doppler echocardiographic characteristics of 57 normally functioning Sorin prosthetic valves (a tilting valve) in the mitral position were studied in the early postoperative period. The three valve sizes (in mm) studied were: 25 (n = 15), 27 (n = 32) and 29 (n = 10). The mean gradients (mmHg) and the valve area (Sq cm) calculated by pressure half time method) for the three valve sizes were 3.46 +/- 1.69 and 2.49 +/- 0.26; 3.46 +/- 1.25 and 2.57 +/- 0.44; and 3.2 +/- 1.23 and 2.55 +/- 0.41; respectively. There was no significant difference in gradients and valve area between the three sizes, variations in pressure half time and therefore the calculated valve area was large. Color Doppler evaluation revealed a bifid nonturbulent jet directed anteriorly towards the interventricular septum. 12 patients (20%) had mild valvar and 7 (12%) had paravalvar mitral regurgitation (mild in 5 and moderate in 2) without any associated prosthetic valve dysfunction. The paravalvar regurgitation persisted in all the 5 patients restudied at 5-12 months postoperatively. Sorin prosthetic valves have similar gradients and valve area when compared to other disc valves. The incidence of of paravalvar regurgitation was slightly higher in our series. The limitations of Doppler derived gradients and area of prosthetic valve are discussed.