Division of Cardiology, Department of Pediatrics, Medical University of South Carolina, Charleston, SC.
Division of Cardiology, Department of Pediatrics, Medical University of South Carolina, Charleston, SC.
J Thorac Cardiovasc Surg. 2017 Dec;154(6):2054-2059.e1. doi: 10.1016/j.jtcvs.2017.06.051. Epub 2017 Jul 5.
Preoperative risk factors associated with poor outcomes after patent ductus arteriosus ligation in preterm infants have not been well defined. The aim of this study was to determine the association between preoperative echocardiographic measures of left ventricular mechanics and postoperative clinical outcomes after patent ductus arteriosus ligation.
Preterm infants less than 90 days of age with no other significant congenital anomalies who underwent patent ductus arteriosus ligation between 2007 and 2015 were considered for retrospective analysis. The primary outcome was peak postoperative vasoactive inotropic score. Conventional echocardiographic measures of ventricular size, function, and patent ductus arteriosus size were performed. Echocardiographic single-beat, pressure-volume loop analysis estimates of contractility (end-systolic elastance) and afterload (arterial elastance) were calculated. Ventriculoarterial coupling was assessed using the arterial elastance/end-systolic elastance ratio. Multivariable linear regression was performed using clinical and echocardiographic data.
Echocardiograms from 101 patients (42.5% male) were analyzed. We found a statistically significant association between vasoactive inotropic score and both end-systolic elastance and arterial elastance. No patient with arterial elastance/end-systolic elastance greater than 0.78 (n = 32) had a vasoactive inotropic score 20 or greater. Analysis of our secondary outcomes found associations between preoperative end-systolic elastance and postoperative urine output less than 1 mL/kg/h at 24 hours, creatinine change greater than 0.5 mg/dL, and time to first extubation.
End-systolic elastance and arterial elastance were the only predictors of postoperative vasoactive inotropic score after patent ductus arteriosus ligation in preterm infants. Those neonates with increased contractility and low afterload were at highest risk for elevated inotropic support. These findings suggest a role for echocardiographic end-systolic elastance and arterial elastance in the preoperative assessment of preterm infants undergoing patent ductus arteriosus ligation.
早产儿动脉导管未闭结扎术后不良结局的术前危险因素尚未明确。本研究旨在确定左心室力学术前超声心动图测量值与动脉导管未闭结扎术后临床结局之间的关系。
回顾性分析 2007 年至 2015 年间接受动脉导管未闭结扎术的小于 90 天龄、无其他重大先天性畸形的早产儿。主要结局指标为术后峰值血管活性正性肌力评分。进行心室大小、功能和动脉导管未闭大小的常规超声心动图测量。计算收缩期弹性（收缩末期弹性）和后负荷（动脉弹性）的超声心动图单次搏动、压力-容积环分析估计值。使用动脉弹性/收缩末期弹性比评估心室-动脉偶联。使用临床和超声心动图数据进行多变量线性回归。
对 101 例患者（42.5%为男性）的超声心动图进行了分析。我们发现血管活性正性肌力评分与收缩末期弹性和动脉弹性均有统计学显著关联。没有动脉弹性/收缩末期弹性比大于 0.78（n=32）的患者血管活性正性肌力评分大于 20。我们对次要结局的分析发现，术前收缩末期弹性与术后 24 小时尿量小于 1ml/kg/h、肌酐变化大于 0.5mg/dL和首次拔管时间之间存在关联。
收缩末期弹性和动脉弹性是早产儿动脉导管未闭结扎术后血管活性正性肌力评分的唯一预测指标。那些收缩力增加和后负荷降低的新生儿发生正性肌力支持升高的风险最高。这些发现表明超声心动图收缩末期弹性和动脉弹性在接受动脉导管未闭结扎术的早产儿术前评估中发挥作用。
