A 44-year-old man comes to the office due to persistent cough and dyspnea on exertion for approximately the last 3 months. He has had no fever, chills, rhinorrhea, or sputum production. Over the past year, the patient has had progressively worsening shortness of breath and is unable to sleep lying flat. He has no chest pain or diaphoresis but has had palpitations previously. The patient does not use tobacco or alcohol. He moved to the United States from Southeast Asia 10 years ago. On examination, the patient is alert but in mild distress. Temperature is 36.7 C (98 F), blood pressure is 110/70 mm Hg, and pulse is 100/min. BMI is 34 kg/m². Heart sounds are distant due to body habitus. The lungs demonstrate crackles on auscultation. Chest x-ray reveals an enlarged cardiac silhouette with vascular congestion. The left main stem bronchus appears to be elevated. There is no other visible lung pathology. ECG shows an irregularly irregular rhythm. Which of the following is the most likely cause of this patient's presentation?

Question

Quizplus · Accepted Answer

11ec25c8_d137_ba88_bc81_45d400fa39ca_MD0003_00 This patient likely has decompensated heart failure due to mitral stenosis. Mitral stenosis usually occurs in the setting of rheumatic heart disease, which in the United States is most often seen in patients who emigrated from Latin America, Africa, or Asia. Mitral stenosis causes eventual backflow of blood into the left atrium, leading to elevated left atrial and pulmonary vascular pressures. This classically presents as dyspnea on exertion, often the only symptom of mitral stenosis, and can progress to pulmonary edema. Manifestations vary from cough (productive or nonproductive, occasionally with hemoptysis) to orthopnea, paroxysmal nocturnal dyspnea, and other features of decompensated heart failure (eg, vascular congestion, enlarged cardiac silhouette). The increased left atrial pressure also leads to left atrial dilation that causes upward displacement of the left mainstem bronchus on chest x-ray. Left atrial dilation can also disrupt atrial electrical conduction, commonly leading to atrial fibrillation (eg, palpitations, irregularly irregular rhythm on ECG). The loss of organized atrial contraction often precipitates an acute decompensation because not enough pressure can be generated to mitigate the elevated left atrial pressures and provide adequate blood flow across the stenotic valve. (Choice A) Patients with acute pericarditis can go on to develop pericardial effusion and cardiac tamponade, with associated dyspnea, orthopnea, and an enlarged cardiac silhouette on chest x-ray. However, this patient has no history of recent infection or chest pain that would suggest acute pericarditis. (Choice B) Interstitial lung disease can present with progressive dyspnea and persistent cough. However, chest x-ray typically shows increased reticular or nodular interstitial markings without significant cardiac enlargement or left main stem bronchus elevation. chest x-ray (Choice C) Primary lung malignancy can present with symptoms of fatigue, chest pain, hemoptysis, weight loss, progressive dyspnea, and persistent cough. However, it is less likely in the absence of a smoking history and is less likely to explain cardiac enlargement on chest x-ray. (Choice E) Sarcoidosis is a systemic granulomatous disease that may be asymptomatic or present with fatigue, weight loss, cough, dyspnea, and chest pain. Chest x-ray usually shows bilateral hilar adenopathy with or without parenchymal reticular opacities. Educational objective: Mitral stenosis usually occurs in the setting of rheumatic heart disease and presents with exertional dyspnea, cough, and orthopnea. Left atrial dilation is typical and may be recognized by elevation of the left main stem bronchus on chest x-ray. Atrial fibrillation is a common complication and can precipitate acute decompensated heart failure in previously well-compensated patients. References: Rheumatic heart disease. (http://www.ncbi.nlm.nih.gov/pubmed/8736683) Mitral stenosis. (http://www.ncbi.nlm.nih.gov/pubmed/19747723)

A 44-Year-Old Man Comes to the Office Due to Persistent