右胸电导纳容积图(小循环心功能测试)法评价二尖瓣手术效果初步报告

二尖瓣狭窄或关闭不全得以纠正（成形或换瓣）后最敏感的血流动力学改变表现在左心房前负荷和（或）肺静脉血容积方面。物理学上，在有顺应性的空间或管道内，容积的改变总是早于压力的变化。右胸电导纳容积图法可敏感地测试到小（肺）循环容积变化，进而反映二尖瓣的生理功能或左心功能的状态。作者对４４例二尖瓣病人手术前后右胸电导纳图小循环心功能进行了观察，其中二尖瓣狭窄１１例、二尖瓣关闭不全７例、狭窄并关闭不全２６例。结果示术前肺静脉负荷指标（ｈＣ／ｈＺ）和心室收缩间期指标Ｑｊ／ｊＺ异常增高；术后早期ｈＣ／ｈＺ恢复或接近正常，Ｑｊ／ｊＺ明显降低；术后１年Ｑｊ／ｊＺ进一步下降，但仍未恢复正常；ｈＣ／ｈＺ改变与左心房压呈极显著正相关（ｒ＝０．７２，Ｐ＜０．００１）。作者认为，此项小循环心功能检测技术无创、简单、易行，对心脏瓣膜病病人手术前、后肺静脉负荷的改变以及术后随访观察病人的心功能状态具比较敏感和可靠等优点。

Preliminary Report on Evaluation of Effectiveness of Mitral Valvular Operation by Lesser Circulation Heart Functional Test with Right Chest Electric Admittance Plethysmography

The most sensitive hemodynamic parameter changed after the mitral operation,either valvular plasty or valvular replacement for mitral stenosis or regurgitation or both,is the preload of the left atrium or the blood volume in the pulmonary vein.According to the physics,the volume change always takes place prior to pressure alterations inside of a compliant space or tube.The lesser circulation heart functional test with right chest electric admittance plethysmography has been proved to be a sensitive test for volume changes in the lesser (pulmonary) ciculation which reflect either the adequacy of the mitral orifice or left ventricular function.For this reason,lesser circulation heart functional tests with right chest electric admittance plethysmography were performed on 44 patients including 11 cases of MS,7 MI and 26 MS MI,before and after mitral operations for correcting the valvular lesions.The results showed that hC/hZ ratio representing the preload of the left heart and Q j/j Z ratio representing ventricular contraction period markedly increased prior to operation.Seven days after the mitral surgery,hC/hZ ratio return to nearly normal range while Q j interval markedly shortened and j Z interval prolonged resulting in significant decrease of Q j/j Z ratio.One year after operation,the j Z interval further prolonged with further decrease of Q j/j Z ratio but not yet to the normal level.The correlative analysis of the data demonstrated that LAP was highly correlated with hC/hZ ratio(r=0.72,P=0.006).The results indicate RCEAPm is a noninvasive and useful new method in assessing the heart function by using the more sensitive parameters.On patients undergoing heart valvular surgery in the immediate postoperativ period and during the late follow up.