This cross-sectional study was conducted at Neonatology, Pediatric Medicine, Pediatric Cardiology and Cardiovascular Surgery OPDs of Seth Sukhlal Karnani Memorial (SSKM) Hospital, Kolkata, India, between December, 2016 to June, 2018. Ethical approval was obtained from the Institutional Ethics Committee of SSKM Hospital. Assent and informed consent were obtained from the participants’ and participant’s guardian wherever applicable, prior to study enrollment. All patients (age 0-14 year) attending relevant OPDs were included. The diagnoses were confirmed by echocardiography, and classified according to Q20-Q28 of tenth revision of International Classification of Diseases (ICD) [5], and International Pediatric and Congenital Cardiac Code (IPCCC) [6]. Major CHDs included atrial septal defect (ASD), ventricular septal defect (VSD), patent ductus arteriosus (PDA), pulmonary stenosis (PS) and tetralogy of Fallot (TOF). ASD <4.0 mm diameter was not considered as a cardiac defect. If a patient had more than one lesion, the defect that required treatment or caused hemodynamic effect was considered the main malformation. Standardized, validated questionnaires administered by trained research assistants were used for collecting data. Age-at-diagnosis was considered 0 day if CHD was reported from maternity ward, or age-at-first hospitalization for CHD, or age-at-cardiac procedure.

Proportion of CHD was calculated as number of pediatric patients affected with CHD out of total attendance of pediatric OPDs in hospital. Chi square tests were used to test difference in proportions among categorical variables. Analysis was done using PC-SAS program (V9.2, SAS institute, Cary, NC, USA).

The high proportion of VSD in our study is in agreement with reported range of 21-53% from other studies [4,7,8]. ASD was the second most common CHD (31.7%), and was higher compared to reported figures of 10-23% in Indian studies [4,7]. TOF was the most common cyanotic heart disease and its proportion (21%) was higher compared to reported figures of 4.6-18.3% [9]. Though our study did not document detailed history on socioeconomic and nutritional background of mothers, our study population comprised mostly middle- and low socioeconomic class, and our findings seem consistent with studies that report premature birth, low socio-economic status and poor nutrition as important factors associated with CHDs among Asian population [10].

Most studies state that 50% of all cases of CHD are detected by 1 month, 75% by 3 months and 100% by 3-4 years age [9]. This variation at CHD detection occurs due to hemodynamic alterations occurring after birth. Our study showed that about 5% of cases were detected by 1 month, majority (83.1%) by 5 years and diagnosis was delayed beyond 10 years in 11.7% of cases. The delay in diagnosis of CHD can be explained by lack of awareness, and less health facilities and pediatric cardiac care programs in India.

The nature of survey only provided us with an estimation of proportion and pattern of CHD and no conclusions can be drawn on prevalence and causality of CHD from this study. Nevertheless, this is the first survey from eastern India providing an up-to-date data on CHD, and filling some gaps in knowledge of CHD from this geographical region.

Contributors: SC, SD, NB: study conception, analysis and interpretation of data, and manuscript writing; SG, SD: data collection and manuscript revision. All authors approved the final version of manuscript and agree to be accountable for all aspects of this work.

Funding: Department of Health Research, Ministry of Health and Family Welfare, Government of India as HRD Fellowship – Start-up grant.

Competing Interest: None stated.

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