Predictors of Unfavourable Outcomes in Children and Adolescents Submitted to Surgical Mitral Valvuloplasty Secondary to Chronic Rheumatic Heart Disease

Abstract Background: Mitral valve repair in paediatric patients with chronic rheumatic heart disease is superior to valve replacement and has been used with good results. Objective: To identify predictors of unfavourable outcomes in children and adolescents submitted to surgical mitral valvuloplasty secondary to rheumatic heart disease. Methods: Retrospective study of 54 patients under the age of 16 operated at a tertiary paediatric hospital between March 2011 and January 2017. The predictors of risk for unfavourable outcomes were: age, ejection fraction, degree of mitral insufficiency, degree of pulmonary hypertension, presence of tricuspid insufficiency, left chamber dilation, preoperative functional classification, duration of cardiopulmonary bypass, duration of anoxia, presence of atrial fibrillation, and duration of vasoactive drug use. The outcomes evaluated were: death, congestive heart failure, reoperation, residual mitral regurgitation, residual mitral stenosis, stroke, bleeding and valve replacement. For all analyzes a value of p < 0.05 was established as significant. Results: Of the patients evaluated, 29 (53.7%) were female, with an average of 10.5 ± 3.2 years. The functional classification of 13 patients (25%) was 4. There was no death in the sample studied. The average duration of extracorporeal circulation was 62.7±17.8 min, and anoxia 50 ± 15.7 min. The duration of use of vasoactive drug in the immediate postoperative period has an average of 1 day (interquartile interval 1-2 days). The logistic regression model was used to evaluate the predictive variables for each unfavourable outcome. The duration of use of vasoactive drug was the only independent predictor for the outcomes studied (p = 0.007). Residual mitral insufficiency was associated with reoperation (p = 0.044), whereas tricuspid insufficiency (p = 0.012) and pulmonary hypertension (p = 0.012) were associated with the presence of unfavourable outcomes. Conclusion: The duration of vasoactive drug use is an independent predictor for unfavourable outcomes in the immediate and late postoperative period, while residual mitral regurgitation was associated with reoperation, and both tricuspid regurgitation and pulmonary hypertension were associated with unfavourable outcomes.

摘要 背景：慢性风湿性心脏病患儿的二尖瓣修复术（mitral valve repair）效果优于瓣膜置换术（valve replacement），且临床应用效果良好。目的：明确风湿性心脏病继发外科二尖瓣成形术（surgical mitral valvuloplasty）的儿童及青少年患者不良预后的预测因素。方法：回顾性分析2011年3月至2017年1月间，某三级儿童医院收治的54例16岁以下接受手术的患者。本次研究评估的不良预后风险预测因素包括：年龄、射血分数（ejection fraction）、二尖瓣反流（mitral insufficiency）程度、肺动脉高压（pulmonary hypertension）程度、三尖瓣反流（tricuspid insufficiency）情况、左心腔扩张（left chamber dilation）情况、术前功能分级（preoperative functional classification）、体外循环（cardiopulmonary bypass）时长、缺氧（anoxia）时长、心房颤动（atrial fibrillation）情况以及血管活性药物（vasoactive drug）使用时长。本次研究评估的结局指标包括：死亡、充血性心力衰竭（congestive heart failure）、再次手术、残余二尖瓣反流（residual mitral regurgitation）、残余二尖瓣狭窄（residual mitral stenosis）、脑卒中、出血事件及瓣膜置换术。所有统计分析均以p<0.05作为显著性阈值。结果：纳入研究的患者中，29例（53.7%）为女性，平均年龄为10.5±3.2岁。13例患者（25%）的功能分级为4级。本研究样本中无死亡病例。体外循环平均时长为62.7±17.8分钟，缺氧平均时长为50±15.7分钟。术后即刻血管活性药物使用时长的平均值为1天（四分位间距（interquartile interval）为1~2天）。采用logistic回归模型（logistic regression model）对各项不良预后的预测变量进行评估。结果显示，血管活性药物使用时长是本次研究中唯一的独立预后预测因素（p=0.007）。残余二尖瓣反流与再次手术相关（p=0.044），而三尖瓣反流（p=0.012）与肺动脉高压（p=0.012）则与不良预后的发生相关。结论：血管活性药物使用时长是术后即刻及远期不良预后的独立预测因素；残余二尖瓣反流与再次手术相关，三尖瓣反流与肺动脉高压均与不良预后的发生存在关联。