二尖瓣病变患者运动负荷测验通气功能特点

二尖瓣病变患者多有活动后呼吸困难，探讨其运动时通气功能特点，方法：２３例女性患者采用踏车运动测验，以１０例正常女性作为对照。结果ＭＶＤ组ＶＯ２ａｘ／ｋｇ、ＶＯ２ＡＴ／ｋｇ、ＶＥｍａｘ、ＶＴｍａｘ、ＲＲｍａｘ、ＶＣＯ２ｍａｘ与ＤＩｍａｘ均低于对照组。

Ventilation during Exercise Test in Mitral Valve Disease

Objective: Rheumatic mitral valve disease(MVD)patients often complained exertional dyspnea. To investigated ventilation of MVD patients during exercise. Method: Cycle ergometer exercise testing with 16W/whn increment was carried out in 23 famales MVD patients and 10 normal females as controls. Results: During maximum exercise MVD patients compared with controls showed that in MVD group VO_2max/kg, VO_2max/kg, VEmax, VTmax, RRmax, VCO_2max and DImax were lower than controls, but VD/VTmax and VE/VCO_2 max were higher than controls. Slope of MVD in plot VEVO_2 shifted to left. Conclution: MVD patients had a higher level of VE at the same VO_2 espeially the energy was supplied from anaerobic metabolism during exercise, and consistence with cardiac dysfunction. MVD patients prefered rapid shallow breathing pattern to high VT for increasing VE. The fact that VD/VTmax and VE/VCO_2max were increased in MVD indicated lower respiratory efficiency. Four cases of tham after PBMV and cardiac function improved, the curve of VE-VO_2 shifted to right and near to normal. MVD patients had a higher ventilatory reserve and stopped exercise at DI max 0.5 because of cardiac limitation.