A 45-year-old man who recently immigrated to the United States from China comes to the physician because of dyspnea, fatigue, and abdominal distention for the past 2 months. He has no other medical problems and takes no medication. The patient has worked as a farmer his entire life. His temperature is 36.7° C (98° F), blood pressure is 110/60 mm Hg, pulse is 80/min, and respirations are 16/min. Examination shows pedal edema, increased abdominal girth with free fluid, and elevated jugular venous pressure without inspiratory decline. Chest auscultation reveals decreased heart sounds and an accentuated sound directly after the second heart sound in early diastole. Chest x-ray demonstrates a ring of calcification around the heart, and jugular venous pressure tracings show prominent x and y descents. Which of the following is the most likely cause of this patient's symptoms?
Features of constrictive pericarditis | |
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Clinical presentation |
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Diagnostic findings |
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*Increase in JVD with inspiration. JVD = jugular venous distension. | |
The most likely diagnosis in this patient is constrictive pericarditis, a condition marked by pericardial fibrosis and obliteration of the pericardial space. Constrictive pericarditis impairs ventricular filling during diastole, causing patients to experience symptoms related to decreased cardiac output (fatigue and dyspnea on exertion) and signs of venous overload (elevated JVP, ascites, and pedal edema). Kussmaul's sign, defined as lack of the typical inspiratory decline in central venous pressure, and the presence of a pericardial knock (early heart sound after S2) may also be seen. Sharp x and y descents are characteristically seen on central venous tracing. Pericardial calcifications can sometimes be seen on chest x-ray and, when present, help confirm the diagnosis.
In developing countries and endemic areas (eg, Africa, India & China), tuberculosis is a common cause of constrictive pericarditis. In the United States, the most common causes include idiopathic or viral pericarditis (>40%), radiation therapy (~30%), cardiac surgery (~10%), and connective tissue disorders.
(Choice A) Chronic obstructive pulmonary disease and pulmonary emboli are the most common causes of cor pulmonale, which develops due to pulmonary hypertension. Signs of pulmonary hypertension on physical examination include a widely split S2 and increased intensity of the pulmonic component of S2. This patient's pericardial calcifications are more suggestive of constrictive pericarditis.
(Choice B) The pneumoconioses are occupational lung diseases caused by inhalation of inorganic dust; examples include asbestosis and silicosis. Patients may gradually develop dyspnea on exertion, pulmonary hypertension, and cor pulmonale years after exposure. Chest x-ray shows parenchymal nodules (silicosis) and pleural plaques (asbestosis).
(Choice C) Psittacosis is a disease transmitted to humans by birds. Patients present with fever, dry cough, and headache. On physical examination, pulmonary findings are most prominent. Cardiac involvement is rare.
(Choice D) Trypanosoma cruzi is the cause of Chagas disease. It is endemic in South America and may cause megacolon, megaesophagus, and cardiac disease. Chagas disease causes both systolic and diastolic heart failure. It may also cause arrhythmias and mitral/tricuspid regurgitation. This patient's pericardial calcification and lack of cardiomegaly on chest x-ray make this diagnosis unlikely.
Educational objective:
Constrictive pericarditis is caused by pericardial scarring and thickening that result in diastolic heart dysfunction. Patients present with signs of decreased cardiac output and venous overload. Common etiologies in the United States include viruses, cardiac surgery, chest radiation, and idiopathic causes. Tuberculosis is the most common cause in developing countries and endemic areas such as Africa, India, and China.