Taniguchi I
Second Department of Surgery, Tottori University Medical School, Yonago, Japan.
Nihon Kyobu Geka Gakkai Zasshi. 1990 Jul;38(7):1135-44.
Right ventricular function was studied in 9 patients with mitral valve stenosis who underwent mitral valve replacement (St. Jude Medical valve 29-31 mm) (MVR). The right ventricular systolic pressure/end-systolic volume index (RVSP/ESVI) correlated well with right ventricular ejection fraction (RVEF) in the normal control group thus it considered to be a index of right ventricular contractility. At rest, RVEF in the MVR group was significantly lower than that in the control group. However there was no difference in the RVSP/ESVI between both groups. In the MVR group, the total pulmonary resistance index (TPRI) and mean pulmonary arterial pressure (mPAP) were higher than those in the control group. During exercise, the RVSP/ESVI became higher in both groups, but RVEF did not increase in the MVR group. In the control group, RVEF became higher during exercise. In addition, TPRI and mPAP increased in the MVR group but the control group did not show significant changes during exercise. In conclusion, low RVEF after MVR, which reflects pump function of the right ventricle, was not caused by contractile dysfunction of the right ventricle but mainly by excess afterload due to irreversible pulmonary vascular resistance persisting after operation as a result of chronic pulmonary vascular hypertension.
对9例接受二尖瓣置换术（使用29 - 31mm圣犹达医疗瓣膜）的二尖瓣狭窄患者的右心室功能进行了研究。在正常对照组中，右心室收缩压/收缩末期容积指数（RVSP/ESVI）与右心室射血分数（RVEF）相关性良好，因此它被认为是右心室收缩力的一个指标。静息时，二尖瓣置换术组的RVEF显著低于对照组。然而，两组之间的RVSP/ESVI没有差异。在二尖瓣置换术组中，总肺阻力指数（TPRI）和平均肺动脉压（mPAP）高于对照组。运动期间，两组的RVSP/ESVI均升高，但二尖瓣置换术组的RVEF没有增加。在对照组中，运动期间RVEF升高。此外，二尖瓣置换术组的TPRI和mPAP升高，但对照组在运动期间没有显著变化。总之，二尖瓣置换术后低RVEF反映了右心室的泵功能，其并非由右心室收缩功能障碍引起，而是主要由慢性肺血管高压导致术后持续存在的不可逆肺血管阻力引起的后负荷过重所致。
