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Karen K Stout and Alan S Pearlman
American Heart Hospital Journal Volume 7 No.1

A 35-year-old man is admitted for evaluation of non-ST-elevation myocardial infarction (STEMI) and heart failure. He has a history of leukemia treated with chemotherapy and radiation as a child, but has not had a cardiac evaluation in 10 years. He had been well until he developed dyspnea with exertion that progressed to dyspnea at rest over two days. At presentation, his blood pressure is 80/60mmHg, his heart rate is 110bpm, and his oxygen saturation is 91% in room air. Examination demonstrates bibasilar crackles, elevated jugular venous pressure, and a summation gallop without murmur. His extremities are notable for bilateral lowerextremity edema and he is cool to the touch from foot to knee. Chest X-ray demonstrates bilateral effusions, pulmonary edema, and cardiomegaly. Electrocardiogram (ECG) shows relatively low-voltage and non-specific ST changes (see Figure 1). Laboratory data demonstrate a troponin of 1.0mg/dl (upper limit of normal 0.4mg/dl). He is taken urgently to cardiac catheterization out of concern that his symptoms could be related to an acute coronary syndrome. His coronary arteries are normal however, his left ventricular end-diastolic pressu (LVEDP) is 30mmHg. An echocardiogram is ordered to evaluate global LV systolic function and diastolic function and to assess in more detail the reason(s) for the high filling pressures.

Echocardographic Findings
A transthoracic echo study demonstrates moderately decreased LV systolic function with mild biventricular enlargement and moderately increased LV and right ventricular (RV) wall thickness (see Figure 2).It is noted that the myocardium appears bright and granular. The mitral and tricuspid valves appear thickened, with only mild regurgitation. Both atria are significantly dilated (see Figure 3). There is a small pericardial effusion and bilateral pleural effusions. On spectral Doppler recordings, the mitral E velocity is elevated, early deceleration time is shortened, and mitral A velocity is decreased (see Figure 4). The patient is admitted and given intravenous (IV) diuretics and standard heart failure therapies, with rapid clinical improvement. Based on his history and echocardiographic findings, the possibility of amyloidosis is raised. Urine and serum protein electrophoreses are performed, demonstrating a monoclonal immunoglobulin G (IgG) lambda spike concerning for amyloid. Colonic biopsy shows amyloid deposition, and bone marrow biopsy demonstrates plasma cell dyscrasia. Further biopsies are planned to help distinguish between AA and AL amyloid, as the therapeutic and prognostic implications are different.

Discussion
Amyloidosis is a disorder marked by deposition of amyloid material in tissues. Amyloid fibrils are precursors of a variety of serum proteins, and the type of protein is related to the underlying etiology of the disease. There are many types of amyloidosis, some acquired and some hereditary, with different underlying pathophysiologies and prognoses. AA and AL amyloidosis are the most common types seen in adults and in tertiary care centers. AL (primary) amyloidosis is due to deposition of monoclonal protein fragments, and is most commonly associated with plasma cell dyscrasias such as multiple myeloma.