Auscultation of the heart of a 17-year-old boy reveals an increased intensity of the pulmonary component of the second heart sound. He complains of dyspnea on exertion but no other cardiac or pulmonary symptoms. Which of the following explanations is the most likely cause of his dyspnea?
- Pulmonary hypertension is associated with an increased intensity of the second heart sound, which coincides with the end of the T wave on ECG. It is the pulmonic component of the second heart sound that is increased.
- Pulmonary stenosis can cause dyspnea on exertion but auscultation will reveal a systolic murmur and decreased second heart sound (pulmonic component).
- As well, there may be prominent waves in the jugular venous pulse, a right ventricular heave, an ejection click, and a right ventricular fourth heart sound. When signs and symptoms are apparent, pulmonary hypertension is usually moderate to severe.