A 54-year-old woman comes to the office due to exertional dyspnea and fatigue. The patient gets short of breath while walking to a store 2 blocks away from her home. She also has trouble breathing at night and sleeps with 2 or 3 pillows to prop her up. She has had occasional palpitations but no chest pain. The patient takes no medications on a regular basis, and does not use tobacco, alcohol, or illicit drugs. After initial evaluation, she is scheduled for a left heart catheterization, the findings of which are shown below. Which of the following is the most likely diagnosis?

Question

A 54-year-old woman comes to the office due to exertional dyspnea and fatigue.  The patient gets short of breath while walking to a store 2 blocks away from her home.  She also has trouble breathing at night and sleeps with 2 or 3 pillows to prop her up.  She has had occasional palpitations but no chest pain.  The patient takes no medications on a regular basis, and does not use tobacco, alcohol, or illicit drugs.  After initial evaluation, she is scheduled for a left heart catheterization, the findings of which are shown below.  Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

11ec160b_3a92_243d_9249_c74a17aa4aeb_MD0001_00 This patient's left heart catheterization shows pressure tracings consistent with mitral regurgitation (MR). In the cardiac cycle, passive filling of the left atrium with blood from the pulmonary veins (atrial diastole) occurs essentially in sync with left ventricular (LV) systole. Left atrial pressure gradually increases to approximately 10 mm Hg in the normal heart with a characteristic "V wave" created at the end of passive filling. However, in the setting of MR, an incompetent mitral valve allows backflow of blood from the left ventricle during ventricular systole, leading to markedly elevated left atrial pressure during this time. This creates an early and large V wave, the characteristic pressure tracing finding in patients with MR. The elevated left atrial pressure in MR leads to atrial dilation and often precipitates atrial fibrillation, symptomatically manifesting with palpitations. Over time, decompensated heart failure, evidenced by dyspnea and orthopnea in this patient, can also occur. (Choice A) In aortic regurgitation, backflow of blood from the aorta into the left ventricle during diastole results in rapid loss of aortic pressure and elevated LV end-diastolic volume with a compensatory increase in LV stroke volume. Pressure tracings show loss of the aortic dicrotic notch (normally seen around aortic valve closure), rapid decline of aortic pressure during diastole, and elevated peak LV and aortic systolic pressures. There is also early closure of the mitral valve due to elevated LV diastolic pressure. (Choice B) Aortic stenosis causes obstruction of LV outflow resulting in discordance of LV and aortic systolic pressure. Pressure tracings characteristically show peak LV systolic pressure significantly higher than aortic systolic pressure. (Choice D) Mitral stenosis causes elevated left atrial pressures throughout the cardiac cycle with peak atrial pressure occurring at the time of atrial kick, just before the mitral valve closes at the end of ventricular diastole. (Choice E) Tricuspid regurgitation causes an early and large V wave on right atrial pressure tracing, similar to that seen on left atrial pressure tracing in the setting of MR. Left-sided pressure tracings (left atrial, left ventricular, aortic) are minimally affected in tricuspid regurgitation. Educational objective: Left ventricular systole corresponds to the time of passive filling of the left atrium (atrial diastole). Mitral valve regurgitation leads to markedly elevated left atrial pressure during this period, creating the characteristic early and large V wave on left atrial pressure tracing.

A 54-Year-Old Woman Comes to the Office Due to Exertional