Cardiovascular Center, Seoul National University Hospital, Seoul, Korea; Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
Ann Thorac Surg. 2012 Jun;93(6):1888-95. doi: 10.1016/j.athoracsur.2012.01.113. Epub 2012 Apr 25.
Although atrial fibrillation (AF) and decreased exercise capacity are common in chronic mitral regurgitation patients, the relationship between rhythm status and exercise capacity after corrective surgery is largely unknown.
Seventy-one patients undergoing repair or replacement of mitral valve for chronic severe mitral regurgitation were examined with preoperative and 6 months' postoperative cardiopulmonary exercise test and two-dimensional echocardiography. Patients were divided into three groups according to preoperative versus postoperative rhythm (sinus/sinus, SS [n=42]; AF/sinus, AS [n=17]; AF/AF, AA group [n=12]).
Preoperative maximal oxygen consumption was lower and ventilatory efficiency was higher in the AS and AA groups compared with the SS group. However, maximal oxygen consumption improved only in the AS group at 6 months' postoperative cardiopulmonary exercise test (24.0±6.9 versus 24.6±6.1 mL·kg(-1)·min(-1) in the SS group, 19.3±5.9 versus 23.2±6.4 mL·kg(-1)·min(-1) in the AS group, 19.8±5.4 versus 18.8±5.1 mL·kg(-1)·min(-1) in the AA group; p=0.016 for maximal oxygen consumption by analysis of covariance) as well as ventilatory efficiency. Echocardiography verified more significant reduction of left atrial volume in the SS and AS groups than in the AA group (172.2±68.0 versus 96.7±31.0 mL in the SS group, 247.5±77.8 versus 129.2±25.7 mL in the AS group, 316.7±210.0 versus 192.0±95.0 mL in the AA group; p=0.001 for left atrial volume by analysis of covariance) as well as pulmonary artery systolic pressure. When analyzed for significant predictors of postoperative maximal oxygen consumption, being in the AS group but not the SS group was a significant positive predictor when compared with the AA group (β=5.475; p=0.006).
Successful sinus conversion of AF, preferably by maze operation, in patients undergoing surgical correction of chronic severe mitral regurgitation confers improved exercise capacity. Reduction of left atrial volume and pulmonary artery pressure may contribute to this improvement.
尽管心房颤动（AF）和运动能力下降在慢性二尖瓣反流患者中很常见，但节律状态与矫正手术后运动能力的关系在很大程度上尚不清楚。
对 71 例行二尖瓣修复或置换术的慢性重度二尖瓣反流患者进行术前和术后 6 个月的心肺运动试验和二维超声心动图检查。根据术前与术后节律（窦性节律/窦性节律，SS[42 例]；AF/窦性节律，AS[17 例]；AF/AF，AA 组[12 例]）将患者分为三组。
与 SS 组相比，AS 和 AA 组术前最大摄氧量较低，通气效率较高。然而，只有 AS 组在术后 6 个月的心肺运动试验中最大摄氧量增加（SS 组 24.0±6.9 与 24.6±6.1mL·kg^-1·min^-1，AS 组 19.3±5.9 与 23.2±6.4mL·kg^-1·min^-1，AA 组 19.8±5.4 与 18.8±5.1mL·kg^-1·min^-1；p=0.016 时协方差分析的最大摄氧量）和通气效率。超声心动图证实 SS 组和 AS 组的左心房容积较 AA 组明显减小（SS 组 172.2±68.0 与 96.7±31.0mL，AS 组 247.5±77.8 与 129.2±25.7mL，AA 组 316.7±210.0 与 192.0±95.0mL；p=0.001 时协方差分析的左心房容积）和肺动脉收缩压。分析术后最大摄氧量的显著预测因子时，与 AA 组相比，AS 组而非 SS 组是术后最大摄氧量的显著正预测因子（β=5.475；p=0.006）。
慢性重度二尖瓣反流患者行二尖瓣修复或置换术后，AF 成功转为窦性心律（最好通过迷宫手术）可改善运动能力。左心房容积和肺动脉压的降低可能有助于这种改善。
