A 32-year-old woman comes to the outpatient clinic due to shortness of breath for the past 6 months. The patient says she can walk only 3-4 blocks on level ground before feeling out of breath. She also has an occasional dry cough at night. The patient denies any chest pain, palpitations, syncope, weight loss, or lower extremity swelling. She immigrated from Guatemala 8 years ago. Medical history is unremarkable. On physical examination, the patient appears comfortable. Blood pressure is 128/75 mm Hg and pulse is 78/min and regular. Peripheral pulses are full and symmetric. The lungs are clear on auscultation. S1 is loud. With the patient positioned on her left side and breath held at the end of expiration, a diastolic murmur is heard at mid- and end diastole. Otherwise, examination is unremarkable. Which of the following are the most likely left ventricular hemodynamic findings at rest in this patient?

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11ec160b_3c9b_61ab_9249_45536bcabbbc_MD0001_00 This patient's mid-to-late diastolic murmur is consistent with mitral stenosis (MS). MS usually occurs due to underlying rheumatic heart disease, which in the United States is most commonly seen in patients who emigrated from Latin America, Africa, or Asia. MS can lead to heart failure due to restriction of left ventricular (LV) diastolic filling. Patients usually experience exertional dyspnea as the first symptom, which results from an inability to increase cardiac output to meet exertional demands. As MS worsens, elevated left atrial pressure can lead to orthopnea, paroxysmal nocturnal dyspnea, productive cough/hemoptysis, and eventual right-sided heart failure with resulting jugular venous distension and lower extremity edema. This patient's presentation with exertional dyspnea in the absence of volume overload (ie, dry cough, no pulmonary crackles, no peripheral edema) suggests relatively early, mild-to-moderate disease. A loud S1 (caused by the stiff leaflets snapping shut) is further suggestive of more mild disease, as the intensity of S1 diminishes with disease progression due to heavy calcification that limits valve motion. Although severe MS can cause reductions in LV diastolic pressure and afterload (due to reduced ventricular filling), these parameters typically remain normal until later in the disease course (especially at rest). LV contractility is also normal at rest in early disease; however, with severe MS the reduction in cardiac output stimulates increased sympathetic activity to increase LV contractility. (Choices A and C) Decreased LV contractility occurs in heart failure due to LV systolic dysfunction (eg, dilated cardiomyopathy, ischemic heart disease). LV diastolic pressure and afterload are initially near normal but increase over time due to worsening systolic function and progressive ventricular dilation. (Choice B) Increased LV diastolic pressure in the setting of normal contractility occurs in heart failure due to LV diastolic dysfunction. Depending on etiology, afterload may be increased (eg, early stages of hypertensive heart disease) or normal (eg, cardiac amyloidosis). Educational objective: Mitral stenosis usually occurs due to underlying rheumatic heart disease and initially presents with exertional dyspnea. Orthopnea, paroxysmal nocturnal dyspnea, productive cough, and hemoptysis can develop as the disease becomes more advanced. At rest, left ventricular diastolic pressure, afterload, and contractility remain normal until the mitral stenosis is severe. __________ References: Mitral stenosis. (http://www.ncbi.nlm.nih.gov/pubmed/28613493)

A 32-Year-Old Woman Comes to the Outpatient Clinic Due to Shortness