Residual Lesions Linked to Postoperative Congenital Cardiac Surgery Outcomes

Fallot’s tetralogy. Colored X-ray of the chest of an infant with Fallot’s tetralogy and rickets. Fallot’s tetralogy is a congenital heart defect that results in insufficient oxygen in the blood (cyanosis), which can cause the baby to turn blue. It is caused by 4 malformations of the heart. There is a hole between the 2 bottom chambers (ventricles) of the heart, a narrowing of the valve leading to the pulmonary arteries, a thickening of the right ventricle and blood can enter the aorta from both ventricles, not only the left. Treatment is with a series of operations. Rickets, soft bones due to a lack of vitamin D, has lead to a misshapen chest. It is treated with vitamin D supplements.
This study evaluated factor associated with outcomes after cardiac surgery for congenital heart defects.

Residual lesions after congenital cardiac surgery are associated with in-hospital outcomes, with the greatest effects occurring after more complex operative procedures, according to a study recently published in the Journal of the American College of Cardiology.

This multicenter, prospective observational study included 1149 infants aged <1 year enrolled between 2015 and 2017 for 5 different types of cardiac operations (tetralogy of Fallot [TOF] with pulmonary stenosis repair, n=250; complete atrioventricular septal defect [CAVSD] repair, n=249; arterial switch operation, n=251; coarctation or hypoplastic or interrupted arch with ventricular septal defect [VSD] closure [Arch/VSD], n=150; Norwood operation, n=249). Residual lesion score (RLS) was categorized by clinical events postoperation, as well as by echocardiography.

RLS 1 was classified as trivial/no residual lesions, RLS 2 as minor lesions, and RLS 3 as major residual lesions requiring reintervention before discharge. The study’s primary outcome was alive and out-of-hospital days within 30 days of surgery (60 days for Norwood). Secondary outcomes included postoperative course, days in the hospital, and major medical events. Kruskal-Wallis and analysis of variance were used to assess continuous outcomes across RLS categories, while a Fisher exact test was used for categorical outcome comparison.

Although RLS 2 vs RLS 1 was not consistently significant for different outcomes across operations, categorization of RLS 3 vs RLS 1 was associated with worse outcomes for days alive and out of hospital as well as postoperation stay in hospital. RLS 3 vs RLS 1 was also associated with poorer secondary outcomes following coarctation/interrupted arch with VSD repair and Norwood. RLS accounted for 5% of the variation of the least complex surgery, TOF, and 20% in the most complex operation, Norwood.

Limitations to this study included a small amount of missing data, diverse major medical events, the use of local interpretation for the arterial switch operation, uncertain generalizability of the study’s findings, and a focus on early postoperative (rather than medium- or long-term) outcomes.

“Major residual lesions were most strongly associated with worse in-hospital outcomes in the most complex operations but had less predictive value for operations of lower complexity”, the study authors noted.

Reference

Nathan M, Levine JC, Van Rompay MI, et al.; for the Pediatric Heart Network Investigators. Impact of major residual lesions on outcomes after surgery for congenital heart disease. J Am Coll Cardiol. 2021;77:2382-94.