A 73-year-old man with a 15-year history of hypertension and stage 3 chronic kidney disease presents to the clinic with progressive dyspnea on exertion and bilateral lower extremity edema over the past 3 months. His wife notes he has become increasingly fatigued. Vital signs are: BP 162/96 mmHg, HR 102 bpm, RR 22, SpO2 97% on room air. On physical examination, jugular venous pressure is elevated at 10 cm H2O, the liver is palpable 4 cm below the costal margin and tender to palpation, and there is bilateral pitting ankle edema. Cardiac auscultation reveals a holosystolic murmur at the left lower sternal border that increases in intensity with inspiration. Chest X-ray shows pulmonary edema and cardiomegaly. Transthoracic echocardiography demonstrates severe right ventricular dilatation (RV diameter 5.2 cm) with an ejection fraction of 35%, global hypokinesis, and severe tricuspid regurgitation with an estimated right atrial pressure of 18 mmHg. BNP is 520 pg/mL. Blood cultures are negative, and there is no history of intravenous drug use or recent instrumentation. Which of the following best explains the pathophysiology of this patient's murmur?

1. A)Rheumatic mitral stenosis causing pulmonary hypertension and secondary tricuspid regurgitation
2. B)Primary degenerative tricuspid valve disease with leaflet prolapse
3. C)Functional tricuspid regurgitation secondary to right ventricular dilatation and annular dilationGABARITO
4. D)Acute papillary muscle rupture of the tricuspid valve from myocardial infarction
5. E)Infective endocarditis of the tricuspid valve with vegetation-induced insufficiency