Dardas Petros S, Pitsis Antonis A, Tsikaderis Dimitris D, Mezilis Nikos E, Geleris Parashos N, Boudoulas Harisios K
Thessaloniki Heart Institute, St. Lucas Hospital, Thessaloniki, Greece.
J Heart Valve Dis. 2004 Jan;13(1):27-32.
Despite the effect of mitral valve repair in left ventricular (LV) function having been extensively studied, investigations of left atrial (LA) performance indices are minimal. This prospective study was undertaken to analyze LA volumes, function and work in patients with chronic mitral valve regurgitation (MR) who underwent mitral valve repair; the analyses were conducted both before and six months after surgery.
Twenty patients (15 males, five females; mean age 51.4 +/- 12.5 years) with severe MR (grade IV) due to floppy mitral valve/mitral valve prolapse (FMV/MVP; anterior, posterior or both) underwent mitral valve repair. LA volumes, maximal at mitral valve opening (LAmax); minimal at valve closure (LAmin); and at onset of atrial systole (P-wave on ECG, LAP); and transmitral Doppler A-wave velocity were measured before and six months after surgery. LA stroke volume (LASV) = LAP - LAmin; LA ejection fraction (LAEF) = LASV/LAP; LA kinetic energy (LAKE) = 1/2 x LASV x 1.06 (specific gravity of blood) x A2 (dyne x cm x 10(3)); LA and LV dimensions and functions were assessed at the same time.
NYHA functional class was improved postoperatively by at least one grade. LV systolic and diastolic dimensions were reduced significantly in all patients (p <0.001). LA volumes (LAmax, LAmin and LAP) were decreased significantly in all patients (p <0.001); LASV remained unchanged. LAEF and LAKE were increased significantly (both p <0.001). The A-wave was also increased (p <0.001).
Increased LA work (LAKE) after mitral valve repair, despite a decrease in LA volumes, suggests that LA muscle dysfunction was present before surgery. LA involvement may precede LV involvement. The determination of LA performance and work will help to optimize the timing of surgery in patients with FMV/MVP and MVR.
尽管二尖瓣修复对左心室（LV）功能的影响已得到广泛研究，但对左心房（LA）性能指标的研究却很少。本前瞻性研究旨在分析接受二尖瓣修复的慢性二尖瓣反流（MR）患者的左心房容积、功能和做功情况；分析在手术前和术后六个月进行。
20例因二尖瓣脱垂/二尖瓣脱垂（FMV/MVP；前叶、后叶或两者均有）导致严重MR（IV级）的患者（15例男性，5例女性；平均年龄51.4±12.5岁）接受了二尖瓣修复。在手术前和术后六个月测量左心房容积，二尖瓣开放时最大（LAmax）；瓣膜关闭时最小（LAmin）；以及心房收缩开始时（心电图上的P波，LAP）；并测量二尖瓣多普勒A波速度。左心房搏出量（LASV）=LAP - LAmin；左心房射血分数（LAEF）=LASV/LAP；左心房动能（LAKE）=1/2×LASV×1.06（血液比重）×A2（达因×厘米×10(3)）；同时评估左心房和左心室的大小及功能。
术后纽约心脏协会（NYHA）功能分级至少提高了一级。所有患者的左心室收缩和舒张尺寸均显著减小（p<0.001）。所有患者的左心房容积（LAmax、LAmin和LAP）均显著降低（p<0.001）；LASV保持不变。LAEF和LAKE显著增加（均p<0.001）。A波也增加了（p<0.001）。
二尖瓣修复后左心房做功（LAKE）增加，尽管左心房容积减小，提示手术前存在左心房肌肉功能障碍。左心房受累可能先于左心室受累。测定左心房性能和做功将有助于优化FMV/MVP和MVR患者的手术时机。
