Abstract
Background Congenital heart defects remain the largest group of congenital anomalies and a leading cause of infant mortality. Surgical outcome depends not only on the anatomy of the defect but also on concomitant extracardiac pathology, among which infectious conditions occupy a special position: they are potentially preventable. Objective To determine the prevalence and pattern of infectious comorbidity in children with congenital heart disease, quantify its association with inhospital mortality, and develop an internally validated risk stratification score incorporating infectious factors. Materials and methods A single-centre retrospective comparative study was performed in Almaty, Kazakhstan, over 2012–2022. Five hundred children aged 0 to 18 years were analysed: 350 with extracardiac pathology and 150 without it, together with 295 autopsy observations. The Mann–Whitney and chi-squared tests, logistic regression, characteristic curve analysis, and bootstrapping were applied. Results Extracardiac pathology was registered in 70 % of admissions, concentrated in the neonatal period (59.5 versus 10 %). The leading infectious conditions were pneumonia (62.2 %), congenital infection (28 %), and neonatal sepsis (16 %); their frequency was independent of the haemodynamic type of defect. In-hospital mortality amounted to 17.4 versus 3.3 %. Four of twelve significant mortality predictors were infectious. The scale developed showed an area under the characteristic curve of 0.90 (sensitivity 76 %, specificity 79 %). Conclusions Infectious comorbidity represents a major and potentially preventable component of preoperative risk in children with congenital heart disease. Earlier antenatal detection, targeted screening for congenital infections, and timely referral before pneumonia develops may reduce in-hospital mortality. Bangladesh Journal of Medical Science Vol. 25 No. 04 October’26 Page: 1247-1258