MSFinals-0152

A 55-year-old woman from India visits the general practice clinic, reporting fatigue and tiredness after completing household tasks. During the examination, the physician observes periodic involuntary contractions of her left arm and multiple lumps beneath the skin. The doctor inquires about the patient’s medical history and asks if she had any childhood illnesses. The patient discloses that she had a severe throat infection in India as a child but did not receive any treatment.
What is the most frequent abnormality that can be detected by listening to the heart during auscultation?