小左心室患者瓣膜置换术后早期心脏形态及功能的变化

Structural and functional changes of postoperative small left ventricle patients

目的研究小左心室患者心脏瓣膜术后早期形态学及左心室收缩功能变化。方法2003年1月至2008年8月，51例合并小左心室的风湿性瓣膜病患者接受二尖瓣置换术。男性7例，女性44例，年龄31～69岁，平均（48±5）岁。病程5—49年，平均（18±9）年。患者病变以重度二尖瓣狭窄为主。同期行主动脉瓣置换术6例，冠状动脉旁路移植术1例，三尖瓣成形术48例，左心房血栓清除术36例，左心房折叠术42例。结果围手术期死亡2例（3．9％），1例因不能脱离辅助循环死亡，1例于术后10d死于继发的多脏器功能衰竭。术后早期发生重度低心排血量14例（27．5％），多器官功能不全11例，频发室性心律失常5例。术前及术后早期（7—14d）行超声心动图。左心室舒张末期内径术前（36．5±3．2）mm，术后（38．6±5．3）mm；左心室舒张末期容积指数术前（45．9±3．8）ml／m^2，术后（48．2±7．4）ml／m^2；差异无统计学意义。手术前后射血分数为48．6％±6．7％和52．8％±8．3％，缩短分数为25．5％±3．3％和27．1％±1．3％，差异无统计学意义。结论小左心室患者瓣膜术后早期易发生低心排血量。左心室舒张末期内径术后早期一般不会立即恢复。

Objective To explore the perioperative features of surgical treatment in valvular patients with small left ventricle, and investigate the postoperative early structural changes of left ventricle and its correlation with cardiac function. Methods A total of 51 patients with small left ventricle underwent mitral valve replacement from January 2003 to August 2008. There were 7 males and 44 females with mean age of （48±5） years old. The mean pathologic course was （18 ± 9） years old. The concomitant procedures included aortic valve replacement in 6 cases, coronary artery bypass grafting in 1 case, tricuspid valvularplasty in 48 cases, left atrial thrombi scavenging in 36 eases, and left atrium folding in 42 cases. Results The perioperative mortality was 3.9% （2/51）. Fourteen patients （27. 5% ） suffered from severe low-output syndrome in the earlier period postoperatively. Among them, 5 patients needed secondary cardiopulmonary bypass （CPB） to assist circulation, with the result of 1 patient died of weaning off CPB unsuccessfully, 1 patient revived with intra-aortie balloon pump assisted for another 2 d after termination of CPB and another 1 patient died of multiple organ failure （MOF） 10 d later. Eleven cases complicated with MOF. Five patients complicated with ventricular arrhythmia. The echocardiographic examinations showed that the left ventrieular dimensions didn＇t expand significantly postoperatively at 7 to 14 d postoperatively. Left ventricular end-diastolic diameter （LVEDD） was （36. 5 ± 3.2） mm preoperatively and （ 38.6 ± 5.3 ） mm postoperatively （ P 〉 0. 05 ）. Preoperative LVEDD index （LVEDDI） was （45.9 ±3.8 ） ml/m^2 and postoperative LVEDDI was （48. 2 ± 7.4 ） ml/m^2 （ P 〉 0. 05 ）. The contract function of left ventricle was improved postoperatively but with no statistical significance. Ejection fraction was 48.6% ± 6. 7% preoperatively and 52. 8% ± 8.3% postoperatively. Left ventricular fraction shortness was 25.5% ± 3.3% preoperatively and 27.1% ± 1.3% postoperatively. Conclusions For the patients with small left ventricle usually, the postoperative emphases should be put on the management of low output syndrome. The decreased dimension of left ventricle doesn＇t expand in the early period after valvular operation.