Division of Cardiovascular Surgery, Department of Surgery, University of Toronto, The Hospital for Sick Children, Toronto, Ontario, Canada.
J Thorac Cardiovasc Surg. 2012 Jan;143(1):126-36, 136.e1. doi: 10.1016/j.jtcvs.2011.09.008. Epub 2011 Oct 22.
Low birth weight and prematurity and are known risks for mortality in congenital heart lesions. It is not known whether risks of delayed intervention are offset by benefits of growth and maturation. We explored this question.
All 1618 infants admitted to our institution within 30 days after birth for a congenital heart defect since 2000 were analyzed. Birth details and admission progress notes were detailed on all. For infants requiring cardiac interventions, clinical conference records and progress notes enabled their management to be classified as either USUAL (normal timing and mode of intervention) or DELAYED (intentional delay for growth/maturation). The survival implications of birth weight and prematurity were examined via parametric multiphase methodology with bootstrap resampling. Subsequently, the impact of DELAYED management was sought in propensity-adjusted and multivariable time-related models.
Low birth weight is a strong, robust and independent predictor of death within the first year of life (P < .0001; 99.6% bootstrap resamples). The relationship is nonlinear with an inflection point at approximately 2.0 kg, below which decrements in survival are increasingly pronounced. Prematurity is also associated with poor outcome but less reliably so (P < .0001; 53% resamples); its variance appears partially mitigated by colinearity with multiple factors including diagnosis and chromosomal aneuploidy. Of the 149 infants with birth weight less than 2.0 kg (highest risk and most likely to receive delayed care in this cohort), care was USUAL in 34 and DELAYED in 46. The remaining children received comfort care only (27), were not considered for intervention owing to severe noncardiac problems (12) or were routinely observed for nonurgent lesions (30). Survival between the children weighing less than 2.0 kg and receiving USUAL or DELAYED care was identical (78% ± 2% at 1 year; P = .88), even when adjusted via propensity score (P = 0.65) or multivariable analysis (P = 0.55). Major determinants of death in this very low-birth-weight population were antenatal diagnosis (P = .01), presence of congenital gastrointestinal defects (P = .07), or lesion type (all higher risk: anomalous pulmonary venous drainage, P = .03; pulmonary atresia and intact septum, P = .05; and truncus, P = .01).
For very low-birth-weight neonates (<2.0 kg) with congenital heart defects, imposed delays in intervention neither compromise nor improve survival. Other factors instead appear to account for survival differences, including lesion type, associated noncardiac congenital defects, and antenatal diagnosis.
低出生体重和早产是先天性心脏病患者死亡的已知风险因素。目前尚不清楚延迟干预的风险是否被生长和成熟的益处所抵消。我们探讨了这个问题。
分析了 2000 年以来我院出生后 30 天内入院的 1618 例先天性心脏病患儿的所有资料。所有患儿的出生细节和入院进展记录均详细记录。对于需要心脏介入治疗的患儿，临床会议记录和进展记录可将其管理分类为常规（正常时机和干预模式）或延迟（为生长/成熟而故意延迟）。通过参数多阶段方法和引导重采样检查了出生体重和早产的生存意义。随后，在倾向调整和多变量时间相关模型中寻求了延迟管理的影响。
低出生体重是婴儿期（<1 岁）死亡的强有力、稳健且独立的预测因素（P<.0001；99.6%引导重采样）。这种关系是非线性的，拐点约为 2.0kg，在此之下，生存率的下降越来越明显。早产也与不良预后相关，但可靠性较低（P<.0001；53%的重采样）；其方差似乎部分通过与多种因素（包括诊断和染色体非整倍体）的共线性得到缓解。在 149 名出生体重<2.0kg 的婴儿中（该队列中风险最高且最有可能接受延迟治疗），34 名接受常规治疗，46 名接受延迟治疗。其余患儿仅接受舒适护理（27 例），因严重非心脏问题（12 例）而不考虑介入治疗，或因非紧急病变而常规观察（30 例）。接受常规或延迟治疗的体重<2.0kg 的患儿的生存率相同（1 年时为 78%±2%；P=.88），即使通过倾向评分（P=.65）或多变量分析进行调整（P=.55）也是如此。极低出生体重患儿死亡的主要决定因素是产前诊断（P=.01）、先天性胃肠道缺陷的存在（P=.07）或病变类型（所有风险较高：异常肺静脉引流，P=.03；肺动脉闭锁伴完整室间隔，P=.05；和共同动脉干，P=.01）。
对于出生体重<2.0kg 的极低出生体重新生儿（<2.0kg），介入治疗的延迟既不会影响也不会改善生存率。相反，其他因素似乎解释了生存率的差异，包括病变类型、相关的非心脏先天性缺陷和产前诊断。
