[Echo-Doppler evaluation of normal Starr-Edwards prostheses in mitral and aortic position]

Although the Starr valve still is the most commonly used prosthesis, no systematic Doppler evaluation of its normal functioning has yet been performed. For this reason, 49 patients with mitral (25) or aortic (25) Starr valve and without evidence of cardiac failure, other valve disease or coronary disease were prospectively explored. Parameters measured were: maximum velocity, maximum and mean gradients, half-decrease time under pressure and corresponding valve areas. A. Mitral prosthesis. With Starr valves size 3 M and 4 M, corresponding to diameters of 30 and 32 mm respectively, the results obtained were: Vmax 1,7 +/- 0.3 m/s, maximum gradient 12.3 +/- 4.5 mmHg, mean gradient 5.3 +/- 2.2 mmHg, T1/2 120 + 30 ms, valve area 1.96 + 0.45 cm2. These 5 parameters were not significantly different with 3M and 4M valves. B. Aortic prosthesis. Contrary to mitral valve prosthesis, the results here were influenced by the size of the valve. With Starr valve No 10 (diameter 24 mm), values were: Vmax 3.3 +/- 0.4 m/s, maximum gradient 45 +/- 11.6 mmHg, mean gradient 26.7 +/- 8.8 mmHg. Aortic regurgitation was present in 20 p. 100 of the cases. The validity of the continuity equation was tested for non-invasive determination of the aortic valve functional area.