39-Year-Old Female With an Early Diastolic Heart Sound
39-year-old female with no significant past medical history presented to her primary care physician’s office with exertional dyspnea and fatigue since 2 months and intermittent atypical chest pain. She denied other possible cardiac symptoms (palpitations, paroxysmal nocturnal dyspnea, orthopnea, edema or syncope) and had no fever, weight loss or change in appetite.
On examination, she was comfortable and looked well with a blood pressure of 120/82, pulse of 70 bpm, respiratory rate of 14, no fever, and 100% saturation on room air. Jugular veins were not distended and there were no carotid bruit. Precordial examination revealed a normal non-displaced apex without thrills or heaves.
Auscultatory findings: An early diastolic heart sound was detected, especially with the patient seated and leaning forward (video-audio file 1 of phonocardiogram). Peripheral pulses were normal and there was no edema. The remaining physical examination was normal.
What is the most likely etiology of the diastolic heart sound?