Constrictive pericarditis results from inflammation and fibrosis of the pericardium, ultimately leading to impairment of diastolic filling and right heart failure. Various processes such as inflammation, infection, mediastinal radiation, and pericardial trauma during cardiac surgery, can lead to pericardial constriction. In the United States and other Western countries, many patients with constrictive pericarditis have no history of antecedent infection and are presumed to have had subclinical viral infections as the etiology for pericardial constriction. Often such cases are termed idiopathic when a specific cause is not identifiable. In most surgical series from developed countries, this idiopathic category constitutes the largest group of patients undergoing pericardiectomy for constrictive pericarditis. In our practice among patients undergoing pericardiectomy for constriction, prior cardiac surgery has become the second most common inciting cause. Thus, in many patients, constrictive pericarditis is a consequence of therapies in modern medicine, that is, cardiac surgery and mediastinal radiation.

Common symptoms in patients with constrictive pericarditis include fatigue, peripheral edema, shortness of breath, and abdominal swelling. In decompensated patients, venous congestion, hepatomegaly, pleural effusions, and ascites may occur. Constrictive pericarditis should be suspected in a patient with right heart failure and preserved left ventricular systolic function, especially in the absence of tricuspid valve regurgitation. The differential diagnosis includes other causes of systolic and diastolic heart failure, in particular restrictive cardiomyopathy, as well as chronic liver disease (causing ascites), tricuspid valve disease, and right heart failure due to myocardial infarction, pulmonary embolism, and chronic lung disease. The distinction between constrictive pericarditis and other causes of heart failure is important because pericardiectomy can cure constrictive pericarditis. Diagnosis of constrictive pericarditis is based on characteristic clinical, hemodynamic, and anatomical features determined using echocardiography, cardiac MRI, CT scanning, and, in some patients, cardiac catheterization. Although present in only approximately 30% of patients, pericardial calcification strongly suggests the diagnosis of constriction in a patient with heart failure.

Common echocardiographic findings in patients with constrictive physiology include septal shift that varies with respiration, and variation in transmitral velocities and hepatic vein flow with respiration. The diagnosis of constrictive pericarditis should be suspected when an echocardiogram for any diagnosis reveals abnormal septal motion or diastolic dysfunction with preserved or increased mitral annular e′ velocities. Indeed, in a recent study of echocardiographic findings in constrictive pericarditis, Welch et al. describe five principal variables that were helpful in differentiating constriction from tricuspid valve regurgitation and restrictive cardiomyopathy. These echocardiographic features were respiration-related ventricular septal shift, variation in mitral inflow E velocity, medial mitral annular e′ velocity, ratio of medial mitral annular e′ to lateral e′, and hepatic vein expiratory diastolic reversal ratio. The presence of ventricular septal shift with respiration in combination with either medial e′ ≥9 cm/second or hepatic vein expiratory diastolic reversal ratio ≥0.79 corresponded to a sensitivity (87%) and specificity (91%) in establishing the diagnosis of constriction, and specificity increased to 97% when all three factors were present.

Imaging with CT or cardiac MR is often useful to determine presence or absence of pericardial thickening and other morphologic features. Cardiac MR has the advantages of lack of radiation and ability to provide physiologic information. Normal pericardium should be less than 4 mm in thickness on MR imaging, and with constriction, pericardial thickening may be diffuse or focal and measure up to 9 mm. Other findings on cardiac MR that suggest pericardial constriction include increased diameter of the inferior vena cava (3 cm vs. normal ≤2 cm), septal “bounce,” and gadolinium enhancement of the pericardium.

In some patients, cardiac catheterization is required to determine the diagnosis, and typical findings include elevation and equalization of diastolic filling pressures and reduced cardiac output. Similar to echocardiographic findings, respiratory changes in filling of the left and right ventricles and enhanced ventricular interaction are distinctive hemodynamic features of constriction. These abnormalities have been described as discordance between the pressures in left and right ventricles; during inspiration, filling of the left ventricle is reduced producing a fall in left ventricular systolic pressure as result of the decrease in intrathoracic pressure and increased filling of right ventricle. This increases right ventricular pressure and pushes the interventricular septum toward the left. With expiration and decreased intrathoracic pressure, right ventricular filling is decreased, but the left ventricle fills, pushing the interventricular septum rightward.

Medical treatment with diuretics may have temporary benefit in some patients, and in the early effusive–constrictive phases of pericarditis, anti-inflammatory drug therapy may be useful. Effusive–constrictive pericarditis (ECP) is being recognized with increasing frequency, and like chronic constrictive pericarditis, may result from a wide variety of causes including infections such as tuberculosis. It is not possible to know which patients with ECP will require pericardiectomy, but a trial medical therapy is usually safe to determine whether the inflammatory changes are reversible.

Pericardiectomy is indicated in patients with symptomatic constrictive pericarditis, especially those patients requiring increasing doses of diuretics. Pericardiectomy is also indicated in patients with ECP who do not respond to anti-inflammatory medications and selected patients with relapsing inflammatory pericarditis. Most patients with relapsing pericarditis improve with medical therapy, but some continue to have intolerable symptoms or complications of corticosteroid use that impairs quality of life. Pericardiectomy should be considered in patients with severe relapsing pericarditis in whom an adequate drug treatment has failed.

Generally, constrictive pericarditis is irreversible, and once the diagnosis of constrictive pericarditis is made in patients with symptoms of heart failure, pericardiectomy is advised. Transient constrictive pericarditis has been reported and some degree of constrictive physiology is not uncommon after cardiac surgery. A limited trial of nonsteroidal anti-inflammatory drugs may be helpful in some patients with recent onset of symptoms.

The contraindications of pericardiectomy are essentially the same with those of other major cardiac procedures. Absolute contraindications include serious systemic illness leading to a limited life expectancy that cannot be prolonged by pericardiectomy, irreversible hepatic dysfunction that has led to cirrhosis, uncontrolled ongoing systemic or local infection, or other systemic disease with multiorgan involvement. In addition, cachectic patients with severe physical or mental disability who are unable to go through recovery process after cardiac surgery are not good candidates for pericardiectomy.

Pericardiectomy for chronic constrictive pericarditis is typically done with supine positioning through median sternotomy. Median sternotomy is chosen when cardiopulmonary bypass is necessary or concomitant procedures are scheduled. Also, pericardiectomy can be done via left anterolateral, or bilateral thoracotomy. Complete pericardiectomy, which only leaves the pericardium along the phrenic nerves and posterior to the left atrium in the oblique sinus, may be difficult through left anterolateral thoracotomy. Because bilateral thoracotomy often produces more pain postoperatively and carries more risk of respiratory problems compared to median sternotomy, its use is reserved for redo surgery or when anterolateral thoracotomy is already performed and its exposure is not sufficient.

The potential advantage of the anterolateral thoracotomy is access to the posterior portion of the pericardium, which may be difficult to expose through the median sternotomy unless cardiopulmonary bypass is used. If the anterolateral approach is used and cardiopulmonary bypass is necessary, cannulation can be performed through the femoral artery and vein or through the axillary artery. The disadvantage of this approach is inadequate access to the right side of the heart if intracardiac repair is necessary. However, it provides excellent exposure of left side of the heart and minimizes risk of cardiac injury in patients who have had previous sternotomy.