A56-year-old man complains of fatigue, dyspnea on exertion, and palpitations. He has had a murmur since childhood. Examination reveals a lift at the left sternal border, split S1, and fixed splitting of S2. There is a grade 3/6 midsystolic pulmonic murmur and a 1/6 middiastolic tricuspid murmur at the lower left sternal border. CXR shows right ventricular enlargement and prominent pulmonary arteries. An ECG demonstrates atrial fibrillation with a RBBB. Which of the following is the most likely diagnosis?
- coarctation of the aorta
- ASD
- patent ductus arteriosus
- tetralogy of Fallot
- VSD
Answer(s): B
Explanation:
ASD is the second most common form of congenital heart disease in adults, after a bicuspid aortic valve.
The murmur heard in childhood is often considered innocent, and symptoms do not appear until adulthood.
A left-to-right shunt of blood between the atria causes right ventricular overload and increased pulmonary circulation. These result in the classic findings of a pulmonic systolic ejection murmur, late pulmonic valve closure with wide splitting of S2, and a tricuspid flow murmur. CXR has signs of cardiomegaly and pulmonary overcirculation. Characteristic ECG changes are atrial fibrillation and an incomplete or complete RBBB. In the more common ostium secundum type of ASD, there is often right axis deviation; whereas, the ostium primum type has a left axis deviation pattern.
Coarctation of the aorta, patent ductus arteriosus, and VSDs are not associated with the findings of the patient described in the question, and tetralogy of Fallot would not present in adulthood.