A 68-year-old woman comes to the office due to a month-long history of worsening fatigue, shortness of breath, and dry cough. The patient has symptoms that worsen with exertion and when lying flat. She has had no chest pain, palpitations, or lightheadedness. The patient has a history of hypertension and breast cancer that is in remission after surgery and doxorubicin-based chemotherapy 15 years ago. She does not use tobacco, alcohol, or illicit drugs. Blood pressure is 110/62 mm Hg and pulse is 94/min. Physical examination shows crackles at the lung bases and bilateral pedal edema. Which of the following sets of findings are most likely present in this patient?

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11ec160b_3a74_d801_9249_0fc169f6c0d1_MD0001_00 This patient with fatigue, dyspnea on exertion, orthopnea, cough, and lower extremity swelling is in acute decompensated heart failure. Anthracycline chemotherapeutic agents (eg, doxorubicin) are a common cause of dilated cardiomyopathy and can precipitate symptomatic heart failure that presents years after exposure. Dilated cardiomyopathy results from a direct insult to cardiomyocytes that impairs their contractile function. There is an increase in left ventricular volume that is initially compensated for by the Frank-Starling mechanism and later by eccentric hypertrophy to maintain cardiac output. However, overwhelming wall stress eventually leads to marked impairment in myocardial contractile function, reduced cardiac output, and symptomatic decompensated heart failure. The elevated left ventricular end-diastolic pressure (LVEDP) is transmitted backward to the pulmonary veins and capillaries, leading to pulmonary edema (evidenced by crackles on lung auscultation). Patients with advanced heart failure also develop elevated right atrial pressure (RAP). RAP is representative of central venous pressure and elevation is indicative of underlying volume overload and possible right-sided heart failure (which most commonly occurs secondary to left-sided heart failure due to backward transmission of elevated pressure overloading the right ventricle). In addition, since the underlying insult in dilated cardiomyopathy often directly affects the right ventricular myocardium, concomitant right ventricular failure is particularly likely in these individuals. (Choice A) Decreased RAP and LVEDP can occur in the setting of intravascular volume depletion. (Choices B and F) Increased LVEDP with normal or decreased RAP can occur early in the course of left-sided heart failure (eg, due to prolonged systemic hypertension). However, by the time overt signs of volume overload develop (eg, peripheral and pulmonary edema), RAP is invariably elevated. (Choices C and E) Increased RAP with normal or decreased LVEDP suggests right-sided heart failure in the absence of left-sided heart failure, as can occur with pulmonary arterial hypertension or hypoxic lung disease (eg, interstitial lung disease). Right ventricular output is impaired, causing reduced blood flow through the lungs to the left atrium (low or normal left-sided pressures). In contrast, this patient's pulmonary crackles are indicative of increased left-sided pressures. Educational objective: Patients with decompensated heart failure have elevated left ventricular end-diastolic pressure and decreased cardiac output that is most often primarily due to left ventricular dysfunction. Right atrial pressure (ie, central venous pressure) is also elevated in advanced heart failure due to volume overload; right-sided heart failure (most often occurring secondary to left-sided failure) can also contribute to elevated right atrial pressure.

A 68-Year-Old Woman Comes to the Office Due to a Month-Long