Infants with congenital heart diseases often require mechanical ventilation and a prolonged intensive care unit (ICU) stay due to complex cardiopulmonary complications. The primary objective of the study was to determine the incidence and predictors of tracheal extubation failure in infants undergoing modified Blalock-Taussig shunt (MBTS). The secondary objective was to evaluate if extubation failure was associated with increased mortality and longer ICU and hospital stays.