A 37-year-old woman comes to the emergency department due to left-sided weakness that started several hours ago. She has had no fever, headache, or vision changes. Over the past 6 months, the patient has had progressive exertional dyspnea, nocturnal cough, and occasional hemoptysis. She also has had frequent episodes of palpitations and an irregular heartbeat. The patient emigrated from Cambodia 2 years ago. She has never used tobacco and does not use alcohol. On neurologic examination, left-sided hemiparesis is present. Which of the following is the most likely diagnosis?
Mitral stenosis in adults | |
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This patient's left-sided hemiparesis is likely due to thromboembolic stroke from atrial fibrillation in the setting of mitral stenosis (MS).
In a young patient from a developing country, progressive dyspnea, nocturnal cough, and hemoptysis are highly suggestive of MS due to rheumatic heart disease. Long-standing MS leads to an increase in left atrial pressure, which in turn leads to elevated pulmonary pressures and pulmonary vascular congestion; these changes can cause dyspnea, orthopnea, paroxysmal nocturnal dyspnea, and hemoptysis and can eventually lead to right-sided heart failure.
In addition, the increased left atrial pressure causes left atrial enlargement that predisposes to the development of atrial fibrillation (evidenced by palpitations and an irregular heartbeat), increasing the risk of left atrial thrombus formation and systemic thromboembolic complications (eg, stroke).
(Choice A) Rheumatic heart disease can involve the aortic valve and lead to aortic stenosis or aortic regurgitation (AR); however, mitral valve involvement is much more common. Left atrial pressures are typically lower in patients with AR than in those with MS. Hemoptysis, atrial fibrillation, and cardioembolic stroke are much more likely to occur with MS than with AR.
(Choice B) Hypertrophic cardiomyopathy (HCM) is an inherited disorder of the cardiac sarcomere characterized by left ventricular hypertrophy that is most prominent at the interventricular septum. Depending on the extent of hypertrophy and outflow tract obstruction, patients may have fatigue, exertional dyspnea, chest pain, palpitations, presyncope, or syncope. Hemoptysis is not expected, and atrial fibrillation is rare.
(Choice D) Pulmonary arterial hypertension refers to an elevation in pulmonary arterial pressure resulting from increased resistance in the pulmonary arterioles, and it most commonly presents in women in their 30s-40s. Exertional dyspnea is common; however, because the left atrium is unaffected, left atrial enlargement is unlikely. Therefore, atrial fibrillation and left atrial thrombus formation are not expected.
(Choice E) Wolff-Parkinson-White (WPW) syndrome involves the development of paroxysmal supraventricular tachycardia (usually atrioventricular reentrant tachycardia) due to the presence of an accessory pathway. Patients commonly have palpitations during episodes, but hemoptysis, exertional dyspnea, and thromboembolic complications are not expected.
Educational objective:
Mitral stenosis leads to an increase in pulmonary pressures and pulmonary vascular congestion, manifesting as dyspnea, orthopnea, paroxysmal nocturnal dyspnea, and hemoptysis. It also causes left atrial enlargement, predisposing to atrial fibrillation and systemic thromboembolic complications (eg, stroke).