Normall, shortening of the minor (transverse) axis accounts %85-90 of the left ventricular
stroke volume. The change in shapc and orifice area of mitral valve during systolic
contraction has bccn shown. Large diameter mitral valves provide large orifice area with low
diastolic gradient but may cause the limitation in the shortening of the minor axis during
systole and led to a detcrioration in systolic functiotı. in this stduy, left ventricular functions
of 12 patients treated with 29 mm, and 15 patients treated with 31 mm mitral valve
replacement with Mcdtronic-Hall prosthetic valve were evaluated with two-dimensional
echocardiographic techniquc in the late postopcrative period (postoperative 16-34 month).
There was no differcnce between two groups preoperatively. Jn the late postoperative
period, ejection fraction (EF) was found significantly higher and end systolic volume index
(ESVI) significantly lower in the 29 mm valve group (EF: %68±7 and %60.5±7; ESVI: 29.9+12.7
and 42.3+14.1 in 29 and 31 mm valve group respectivcly, p<0.05). Differences between
enddiastolic volume index (EDVI) and stroke volume index (STKVI) were not found as
significant statistically. in conclusion, large diameter mitral valve may have ncgative effcct on
left ventricular systolic function.