A 65-year-old man is evaluated for progressive shortness of breath. He has had exertional dyspnea for the past year and has been experiencing weight gain and peripheral edema for the last several weeks. He has no previous history of cardiac or pulmonary disease. Cardiac biopsy of the left ventricle shows the histopathologic findings on the slide below. Which of the following are the most likely echocardiographic findings in this patient?

Question

A 65-year-old man is evaluated for progressive shortness of breath. He has had exertional dyspnea for the past year and has been experiencing weight gain and peripheral edema for the last several weeks. He has no previous history of cardiac or pulmonary disease. Cardiac biopsy of the left ventricle shows the histopathologic findings on the slide below.

Which of the following are the most likely echocardiographic findings in this patient?

Quizplus · Accepted Answer

11ec160b_38b0_4546_9249_fd4cb3d5b468_MD0001_00 This patient with decompensated heart failure (eg, progressive dyspnea, weight gain, peripheral edema) has copious pink, amorphous material (hyaline) on cardiac biopsy, which is characteristic of amyloid cardiomyopathy. Amyloidosis is a systemic disorder caused by the extracellular deposition of fibrils of misfolded amyloid protein in various tissues (eg, liver, kidney, blood vessels), resulting in organ enlargement and dysfunction (eg, hepatomegaly, nephrotic syndrome, easy bruising). Cardiac amyloid deposition typically causes a restrictive cardiomyopathy with uniformly thickened ventricular walls (normal thickness is seen with other noninfiltrative etiologies) that are stiff with impaired diastolic relaxation. Left ventricular (LV) cavity size is normal or decreased, and the impaired diastolic relaxation both increases LV filling pressure and reduces cardiac output (leading to dyspnea). The elevated LV pressure is transmitted backward, leading to left atrial dilation, increased pulmonary arterial pressure, and progressive right-sided heart failure (eg, jugular venous distension, peripheral edema). (Choice A) A dilated left atrial cavity with normal LV parameters is indicative of mitral stenosis. Patients typically have pulmonary edema in addition to symptoms of right-sided heart failure. Accumulation of amorphous extracellular material is not expected on autopsy. (Choice B) Dilated left atrial and ventricular cavities with normal LV wall thickness is consistent with dilated cardiomyopathy, which results from contractile dysfunction after direct myocardial insult (eg, infection, chronic alcohol toxicity). LV relaxation may be normal or impaired depending on the disease progression and underlying etiology. Interstitial fibrosis would be prominent on microscopy in addition to findings specific to the underlying cause (eg, inflammatory cells in viral myocarditis). (Choice D) These changes are not characteristic of any specific cardiac condition. (Choice E) Normal left atrial cavity size with a dilated LV cavity and thickened LV walls but normal LV relaxation is consistent with the changes that occur in response to intense endurance training in an athlete's heart. As these changes are physiologic, decompensated heart failure does not occur. Educational objective: Amyloid cardiomyopathy, caused by the accumulation of misfolded amyloid fibrils, appears as pink, amorphous extracellular material on light microscopy. The ventricular walls become stiff and uniformly thickened, leading to impaired diastolic relaxation, a dilated left atrial cavity, and progressive left- and right-sided heart failure. Left ventricular cavity size is typically normal or decreased. __________ References: Serial Doppler echocardiographic follow-up of left ventricular diastolic function in cardiac amyloidosis. (http://www.ncbi.nlm.nih.gov/pubmed/2229760) Comprehensive Doppler assessment of right ventricular diastolic function in cardiac amyloidosis. (http://www.ncbi.nlm.nih.gov/pubmed/2295749)

A 65-Year-Old Man Is Evaluated for Progressive Shortness of Breath