This patient most likely has mitral stenosis (MS), which causes increased pressure proximal to the stenosis, sparing the left ventricle.
This patient presents with signs and symptoms of heart failure, and on exam has a murmur consistent with mitral stenosis (MS). MS causes increased pressure proximal to the stenosis, and can result in increased pulmonary capillary wedge pressure, increased PA systolic pressure, loss of pulmonary vascular compliance, a dilated RV, and perhaps functional tricuspid regurgitation. However, it is important to note that the left ventricle is spared and does NOT experience increased pressure, and so PCWP is not an accurate measure of LVEDP. Indeed, the gradient between the PCWP (which should be equal to left atrial pressure) and the left ventricle is used to grade the severity of MS.
Shipton and Wahba discuss the management of valvular disease. Specifically, they state that balloon valvuloplasty is an effective treatment for mitral stenosis that is recommended for any patients with New York Heart Association Heart Failure Class II, III, or IV.
Hildick-Smith et al. discuss whether PCWP is an accurate measurement of left atrial pressure. They measured PCWP in 36 patients and compared it to left atrial pressure and found that while PCWP is an accurate estimator of left atrial pressure, it overestimates the transmitral gradient
Illustration A demonstrates the classic "fish mouth" appearance of a stenotic mitral valve.
Illustration B shows the relationship between transmitral gradient (LVEDP - LA pressure) and MS severity.
Video V demonstrates the late diastolic murmur associated with mitral stenosis.
Answer 1: Pulmonary vascular compliance is decreased in MS.
Answer 2: PASP is increased in MS.
Answer 3: LVEDP is typically normal in MS.
Answer 5: This patient has signs of severe MS, and likely has an increased transmitral gradient.
Shipton B, Wahba H. Valvular heart disease: review and update. Am Fam Physician. 2001 Jun 1;63(11):2201-8. Review.
PMID:11417772 (Link to Abstract)
Hildick-Smith DJ, Walsh JT, Shapiro LM. Pulmonary capillary wedge pressure in mitral stenosis accurately reflects mean left atrial pressure but overestimates transmitral gradient. Am J Cardiol. 2000 Feb 15;85(4):512-5, A11.
PMID:10728964 (Link to Abstract)
USMLE World Step 1 QBank Question #234. Copyright © USMLEWorld, LLC 2012