Constrictive pericarditis occurs when a scarred, thickened, and calcified pericardium impairs cardiac filling. The pathophysiological hallmark of pericardial constriction is equalization of the end-diastolic pressures in all four cardiac chambers. This occurs because the filling is determined by the limited pericardial volume, not the compliance of the chambers themselves.
Initial ventricular filling occurs rapidly in early diastole as blood moves from the atria to the ventricles without much change in the total cardiac volume. However, once the pericardial constraining volume is reached, diastolic filling stops abruptly. The stiff pericardium also isolates the cardiac chambers from respiratory changes in intrathoracic pressures, resulting in Kussmaul's sign.
Patients with pericardial constriction typically present with manifestations of elevated systemic venous pressures and low cardiac output. Typically, there will be marked jugular venous distension, hepatic congestion, ascites, and peripheral edema. The limited cardiac output typically presents as exercise intolerance. Patients with pericardial constriction are much more likely to have left-sided or bilateral pleural effusions.
Making the diagnosis:
- The normal inspiratory drop in jugular venous distention may be replaced by a rise in venous pressure (Kussmaul's sign).
- The classic auscultatory finding of pericardial constriction is a pericardial knock. This occurs as a high-pitched sound early in diastole when there is sudden cessation of rapid ventricular diastolic filling.
- Pericardial calcification seen on the lateral plane chest x-ray is suggestive of pericardial constriction.
- 2 mm) that can be imaged by echocardiography, CT, and MRI" lfo="3" listitemdepth="1" orderedlistitem="false"> Most patients with pericardial constriction have a thickened pericardium (>2 mm) that can be imaged by echocardiography, CT, and MRI.
- Doppler echocardiography is important in the evaluation of patients with suspected pericardial constriction. The echocardiogram may demonstrate pericardial thickening and calcification. However, increased pericardial thickness can be missed on a transthoracic echocardiogram. Transesophageal echocardiography is more sensitive and accurate in determining pericardial thickness. Doppler echocardiography frequently demonstrates restricted filling of both ventricles.
- In some patients with acute onset pericardial constriction, the symptoms and constrictive features may resolve with medical therapy alone. Medical management includes the use of anti-inflammatory agents, colchicine, and/or steroids.
- In more chronic pericardial constriction, definitive treatment is surgical pericardial decortication with resection of both the visceral and parietal pericardium.