A 64-year-old man is evaluated for lower extremity edema and increasing abdominal discomfort. His past medical history is significant for diet-controlled type 2 diabetes mellitus and mitral valve repair surgery 12 years ago. He has smoked a pack of cigarettes daily for the last 40 years. His blood pressure is 142/80 mm Hg, and pulse is 92/min and regular. Jugular venous pressure is estimated at 16 cm H₂O. A middiastolic sound is heard on cardiac auscultation. Lungs are clear to auscultation. There is significant ascites and 4+ lower extremity edema bilaterally. Laboratory values show serum albumin level of 3.2 g/dL. 24-hour urine protein excretion is 280 mg. Chest x-ray reveals normal heart size, clear lung fields, and spotty calcifications along the left heart border. Echocardiogram shows enlarged atria, normal left ventricular wall thickness, normal right ventricular size, and left ventricular ejection fraction of 65%. There is mild mitral regurgitation. Which of the following is the most likely cause of this patient's symptoms?

Question

Quizplus · Accepted Answer

11ec25c8_d342_3127_bc81_03a6d4d0cc4b_MD0003_00 This patient's presentation with peripheral edema, ascites, and elevated jugular venous pressure (JVP) with clear lung fields is suggestive of right heart failure, most likely due to constrictive pericarditis (CP). CP results from a thickened and often calcified pericardium that limits diastolic filling. Idiopathic pericarditis or pericardial involvement from prior cardiac surgery (eg, coronary artery bypass surgery, cardiac valve surgery), mediastinal irradiation, tuberculosis, malignancy, or uremia are common antecedents. Patients typically present with signs of right heart failure. Other features include hepatic congestion with hepatomegaly and eventual progression to cirrhosis (cardiac cirrhosis). Patients can also have hypoalbuminemia due to protein-losing enteropathy (likely from intestinal lymphangiectasia in the setting of increased systemic venous pressures). Physical examination shows elevated JVP (normal <8 cm H₂O) with prominent y descent, hepatojugular reflux, Kussmaul sign (increase or lack of decrease in JVP on inspiration), pericardial knock (middiastolic sound), and pericardial calcifications on chest radiograph. Echocardiography typically shows increased pericardial thickness, abnormal septal motion, and biatrial enlargement, although some findings (eg, thickness) may be missed or absent. (Choice A) Echocardiography in cardiac amyloidosis will show increased ventricular wall thickness with a normal or nondilated left ventricular (LV) cavity. Patients with amyloidosis may also have nephrotic-range proteinuria (ie, >3.5 g/day), periorbital purpura, and hepatomegaly. This patient's non-nephrotic-range proteinuria likely represents moderately increased albuminuria due to diabetes. (Choice C) Cor pulmonale refers to right ventricular failure from pulmonary hypertension due to severe lung disease (eg, chronic obstructive pulmonary disease), pulmonary vascular disease, or obstructive sleep apnea. Echocardiogram shows pulmonary hypertension, dilated right ventricle, and tricuspid regurgitation. (Choice D) Patients with obstructive coronary artery disease (CAD) typically present with progressive angina and/or dyspnea on exertion. (Choice E) Severe and long-standing hypertension can lead to LV hypertrophy and diastolic heart failure with preserved ejection fraction. There is no such history in this patient. (Choice F) Patients with hypertrophic cardiomyopathy usually present with dyspnea, chest pain, palpitations, and/or presyncope or syncope. Echocardiogram typically shows increased LV wall thickness, most pronounced in the basal anterior septum (asymmetric septal hypertrophy). (Choice G) Inferior vena cava obstruction presents with swelling and edema in the lower extremities due to an increase in the venous pressure below the liver. JVP is usually reduced or normal. (Choice H) Stress-induced cardiomyopathy is characterized by transient LV dysfunction in the absence of significant CAD. It is typically caused by intense physical or emotional stress. Patients often present with substernal chest pain, dyspnea, ECG abnormalities, and elevated cardiac biomarkers. (Choice I) Superior vena cava (SVC) syndrome is caused by external or internal compression of the SVC. This leads to elevated upper body venous pressure, with facial swelling and distended veins in the neck and/or chest wall. Ascites and lower extremity edema are typically not present. (Choice J) Severe tricuspid regurgitation can cause right heart failure similar to the presentation of this patient. However, there are no significant valvular abnormalities on the echocardiogram. Educational objective: Constrictive pericarditis is an important cause of right heart failure and is characterized by progressive peripheral edema, ascites, elevated jugular venous pressure, pericardial knock (middiastolic sound), and pericardial calcifications on chest radiograph. References: Constrictive pericarditis after cardiac surgery. (http://www.ncbi.nlm.nih.gov/pubmed/23266135)

A 64-Year-Old Man Is Evaluated for Lower Extremity Edema and Increasing