左心室射血分数在不同病理瓣膜手术中的临床意义

目的 探讨左心室射血分数(LVEF)在单纯二尖瓣狭窄、二尖瓣关闭不全、主动脉狭窄、主动脉瓣关闭不全瓣膜手术中的指导意义.方法 自1993年1月至2004年12月北京安贞医院心外科共进行瓣膜手术5066例,其中单纯二尖瓣狭窄984例(47.7％),单纯二尖瓣关闭不全653例(31.7％),单纯主动脉瓣狭窄138例(6.7％),单纯主动脉瓣关闭不全288例(13.9％).患者均在体外循环下行瓣膜置换术或瓣膜成形术.分析术前LVEF值对不同病理改变的患者住院病死率的影响,同时对手术前后LVEF值的变化进行比较.结果 按照临床标准,以LVEF≥50％为正常,LVEF＜ 50％为减低.①单纯二尖瓣狭窄患者中,术前LVEF减低患者住院病死率为3.7％ (4/109),LVEF正常患者为3.4％(30/875),两者比较,差异无统计学意义(P＞0.05)；单纯二尖瓣关闭不全患者中,术前LVEF减低患者的住院病死率为12.0％ (10/83),明显高于LVEF正常患者住院病死率3.3％ (19/570)] (P＜0.01)；单纯主动脉瓣狭窄患者中,LVEF减低患者的住院病死率为4.5％ (1/22),LVEF正常患者住院病死率2.6％ (3/116),差异无统计学意义(P＞0.05)；单纯主动脉瓣关闭不全患者LVEF减低患者的住院病死率为8.5％(5/59),明显高于LVEF正常患者2.2％(5/229)](P＜0.05).②单纯二尖瓣狭窄患者中,术前LVEF正常者术后LVEF下降(61±9)％比(64±7)％,P ＜0.01]；LVEF减低者术后LVEF升高(56±11)％比(44±6)％,P＜0.01].单纯二尖瓣关闭不全患者中,术前LVEF正常患者术后LVEF明显下降(58±10)％比(64±7)％,P＜0.01].单纯主动脉瓣狭窄患者中,术前LVEF减低者,术后LVEF明显升高(57±13)％比(43±5)％,P＜0.01]；术前LVEF正常者,术后LVEF下降(60±12)％比(66±9)％,P＜0.01].单纯主动脉关闭不全患者中,术前LVEF正常者,术后LVEF明显下降(57±10)％比(62±7)％,P＜0.01].结论 LVEF在不同病理改变的瓣膜病中意义不同.单纯二尖瓣狭窄中LVEF不是敏感指标,其参考意义有限.单纯二尖瓣关闭不全中LVEF是重要的评估指标.二尖瓣关闭不全中,LVEF降至正常,则预示心功能严重受损,且已失代偿.在单纯主动脉瓣狭窄病变中,LVEF不是反映病变程度的最敏感指标,同时受心室壁张力影响,不能完全代表心肌功能的改变,临床上不应作为判断手术风险的主要指标.单纯主动脉瓣关闭不全中,LVEF可以真实反映左心室功能,且LVEF 值的降低是心脏失代偿的表现,且对预后产生不利影响,因此应作为手术指征和判断预后重要的参考指标之一.

Clinical significance of left ventricular ejection fraction in different pathological valve surgery

Objectives To determine the clinical significance of left ventricular ejection fraction（LVEF） in different pathological valve surgery. Methods All 984 consecutive patients with isolated mitral stenosis（ MS）, 653 patients with isolated mitral insufficiency （MI）, 138 patients with isolated aortic stenosis （AS）, and 288 patients with aortic insufficiency（AI） from 1993 to 2004 were evaluated. All of them underwent valve replacement or repair, and LVEF was detected preoperatively and postoperatively. Results （1）The hospital mortality of patients with preoperative LVEF 〈 50% was similar as that of patients with LVEF ≥ 50% in MS group 3.7% （4/109） vs 3.4% （30/875）, P 〉0.05 ] and AS group4.5% （1/22） vs 2.6% （3/116）, P 〉 0.05 ]. The mortality of patients with preoperative LVEF 〈 50% was significantly higher than that of patients with LVEF ≥50% in MI group 12.0% （ 10/ 83）vs 3.3% （19/570）, P〈0.01] and AI group 8.5% （5/59） vs 2.2% （5/229）, P〈0.05]. （2）In MS group, after treatment, the LVEF of patients with preoperative LVEF ≥50% decreased （61 ±9）% vs（64 ±7）%, P 〈 0.01 ], and increased in patients with preoperative LVEF 〈 50% （56 ± 11 ） % vs （44 ± 6） %, P 〈 0.01 ]. In MI group, after treatment, the LVEF of patients with preoperative LVEF ≥ 50% decreased （58 ± 10） % vs （ 64 ± 7） %, P 〈 0.01 ]. In AS group, after treatment, the LVEF of patients with preoperative LVEF 〈 50% increased （57 ± 13）% vs（43 ± 5）%, P 〈 0.01 ] , and decreased in patients with preoperative LVEF ≥50% （60 ± 12）% vs（66 ± 9）%, P 〈 0.01 ]. In AI group, after treatment, the LVEF of patients with preoperative LVEF ≥ 50% decreased （57 ± 10 ） % vs （ 62 ± 7 ） %, P 〈 0.01 ]. Conclusions LVEF has different influence on hospital mortality in different pathological valve diseases in valve surgery. To MI and AI patients, LVEF is an important risk factor on hospital mortality, but in MS and AS patients, it is not a sensitive index.