An 80-year-old woman comes to the office due to progressive lower extremity edema over the last 2 months. Her mobility is impaired due to knee osteoarthritis, but recently she has become somewhat tired and short of breath with daily activities. Her stomach feels full and her appetite has been decreased. The patient has had no forgetfulness or mood problems. Blood pressure is 136/75 mm Hg and pulse is 70/min and regular. Jugular veins are distended with the patient in the seated position. There are no heart murmurs. Breath sounds are decreased at the bases bilaterally. The abdomen is distended with flank dullness on percussion. There is 3+ peripheral edema. Laboratory results are as follows: Urine albumin excretion is 1 g/24 hr. Echocardiogram reveals left atrial enlargement, marked concentric left ventricular hypertrophy, and left ventricular ejection fraction of 70%. Which of the following is the most likely cause of this patient's symptoms?

Question

An 80-year-old woman comes to the office due to progressive lower extremity edema over the last 2 months.  Her mobility is impaired due to knee osteoarthritis, but recently she has become somewhat tired and short of breath with daily activities.  Her stomach feels full and her appetite has been decreased.  The patient has had no forgetfulness or mood problems.  Blood pressure is 136/75 mm Hg and pulse is 70/min and regular.  Jugular veins are distended with the patient in the seated position.  There are no heart murmurs.  Breath sounds are decreased at the bases bilaterally.  The abdomen is distended with flank dullness on percussion.  There is 3+ peripheral edema.  Laboratory results are as follows: Urine albumin excretion is 1 g/24 hr.  Echocardiogram reveals left atrial enlargement, marked concentric left ventricular hypertrophy, and left ventricular ejection fraction of 70%.  Which of the following is the most likely cause of this patient's symptoms?

Quizplus · Accepted Answer

11ec25c8_d32d_4981_bc81_95b055e2510e_MD0003_00 Amyloidosis can cause multisystemic disease due to fibril deposition in tissues. Cardiac amyloidosis, a form of restrictive cardiomyopathy, should be suspected in patients who have manifestations of congestive heart failure (eg, progressive dyspnea, lower extremity edema, jugular venous distension, ascites) with echocardiographic findings of concentric left ventricular (LV) hypertrophy and nondilated LV cavity, especially in the absence of a history of hypertension. Right heart failure symptoms tend to predominate. As LV wall thickness increases (due to fibril deposition), LV cavity size decreases and a restrictive physiology develops. Atrial enlargement is common and cardiac conduction abnormalities may occur. Restrictive cardiomyopathy is less common than dilated or hypertrophic cardiomyopathy but is an important cause of heart failure with preserved ejection fraction. It may be idiopathic or due to infiltrative diseases (eg, sarcoidosis, amyloidosis), storage diseases (eg, hemochromatosis), or endomyocardial fibrosis. Other clinical manifestations suggestive of amyloidosis include: asymptomatic proteinuria (eg, >300 mg/day), as seen in this patient, or nephrotic syndrome (eg, >3.5 g/day); waxy skin; anemia (seen in this patient); easy bruising with ecchymosis; hepatomegaly; gastrointestinal bleeding; early satiety (also seen in this patient); subcutaneous nodules; enlarged tongue; and peripheral or autonomic neuropathy. (Choice A) Hypertrophic cardiomyopathy is characterized by asymmetric septal hypertrophy and systolic anterior motion of the mitral valve, leading to LV outflow tract (LVOT) obstruction. Patients can be asymptomatic or have dyspnea, chest pain, palpitations, or presyncope/syncope. Cardiac auscultation reveals a harsh ejection systolic murmur at the left sternal border that varies in intensity with physiologic maneuvers. ("Hypertrophic obstructive cardiomyopathy" was dropped in favor of "hypertrophic cardiomyopathy" because LVOT obstruction is not always present; hypertrophic cardiomyopathy should be distinguished from hypertrophy due to other cardiovascular diseases [eg, hypertension, valvular, ischemic].) (Choice B) Inferior vena cava thrombosis can lead to lower extremity edema and ascites. However, jugular venous pressure is typically low or normal, there is no associated proteinuria, and LV hypertrophy would not be expected. (Choice C) Ischemic cardiomyopathy refers to LV systolic dysfunction due to coronary artery disease or prior myocardial infarction. Echocardiogram would reveal wall motion abnormalities and decreased LV ejection fraction. (Choices D and E) Protein malnutrition and generalized edema can occur in patients with heavy proteinuria and nephrotic syndrome. However, congestive heart failure with concentric LV hypertrophy would not be expected. (Choice G) Thiamine deficiency can lead to beriberi heart disease, a form of high-output heart failure that leads to the development of dilated (not hypertrophic) cardiomyopathy. It also would not explain this patient's proteinuria. Educational objective: Amyloid cardiomyopathy should be suspected in patients with unexplained congestive heart failure, proteinuria, and left ventricular hypertrophy in the absence of a history of hypertension. References: Cardiac transthyretin amyloidosis. (http://www.ncbi.nlm.nih.gov/pubmed/22888163)

An 80-Year-Old Woman Comes to the Office Due to Progressive