Objective: To present primary causes of in-hospital mortality in large surgical population who underwent surgical correction for CHDs for the period of a decade at our institute.

Methods: Retrospective analysis of pediatric cardiac surgery database along with decision of morbidity and mor-tality meeting at Department of Cardiac Surgery at CPE Institute of Cardiology from January 2009 to April 2021. Results: An overall 3705 patient underwent surgery for CHDs. The in-hospital mortality for CHDs surgery is 2.37% with RV dysfunction, Residual cardiac defect with valve dysfunction (TR/PR), pulmonary hypertensive complication, mediastinal bleeding, cardiac tamponade, respiratory complication, MODs, heart block as major primary cause of in-hospital mortality with frequency of 15.91%, 18.18%, 18.18%,18.18%,9.09%,10.23%, 4.54% and 4.54% respectively.

Conclusion: in our population of 3705 congenital cardiac surgery patients, incidence of overall in-hospital mortali-ty is promising for wide range of CHDs. RV dysfunction, residual RV defects with vale regurgitation, pulmonary hypertension, bleeding complications and respiratory failure are major primary causes of in-hospital mortality.

Keywords: In-hospital Mortality, Atrial septal defect (ASD), Tetralogy of Fallot (TOF), Ventricular septal defect