Congenital heart disease (CHD) Exam with Questions and Solutions

It covers key domains which include; Septal Defects, Obstructive Lesions, Cyanotic Heart Defects, Single Ventricle Physiology, Multisystem and Late-Stage complications and Neurodevelopmental and Psychiatric Issues. A newborn is found to have a fixed split S2 and a systolic ejection murmur at the left upper sternal border. Which defect is most likely responsible for these findings? a. Ventricular septal defect b. Atrial septal defect c. Patent ductus arteriosus d. Tetralogy of Fallot Correct Answer: b Rationale: An atrial septal defect causes a left-to-right shunt at the atrial level, increasing right heart volume and prolonging right ventricular systole, which produces a fixed split S2 due to consistent delayed pulmonic valve closure regardless of respiration. The systolic ejection murmur at the left upper sternal border results from increased flow across the pulmonic valve rather than turbulence at the defect itself.