Constrictive pericarditis is a condition characterized by the thickening and fibrosis of the pericardium, leading to impaired diastolic filling of the heart. The chronic nature of this condition often results in pericardial inflammation, fibrotic scarring, calcification, and restricted cardiac filling.
The pathophysiology of constrictive pericarditis involves a restrictive, thickened pericardium that limits cardiac volume expansion. Unlike the normal pericardium, the inelastic pericardium in constrictive pericarditis hinders the transmission of intrathoracic pressure changes to the heart chambers during inspiration, leading to impaired ventricular filling. Ventricular interdependence occurs as the right heart volume expands due to the interaction with the left ventricle. The early diastolic filling is rapid, and as the disease progresses, ventricular volumes and stroke volumes decrease.
Hemodynamically, the disease manifests as a dip-and-plateau waveform on pressure tracings, distinguishing it from restrictive cardiomyopathy. The preservation of myocardial function in early diastole helps differentiate constrictive pericarditis from restrictive cardiomyopathy, as systolic function is typically affected only in the late stages. Over time, symptoms of congestive heart failure develop due to inadequate stroke volume, leading to venous engorgement and decreased cardiac output. The clinical presentation and hemodynamic findings underscore the importance of distinguishing constrictive pericarditis from other cardiac conditions for appropriate management.
The etiology of constrictive pericarditis can be broadly classified into common, less common, and rare forms. Common causes encompass idiopathic cases, infections (bacterial, viral, and fungal), radiation therapy, cardiac surgery, and connective tissue disorders. Less common causes involve neoplasms, uremia, drugs, trauma, and myocardial infarction. Rare forms include occurrences after implantation of cardiac devices, Mulibrey nanism, sclerotherapy for esophageal varices, and chylopericardium. The varied etiological spectrum underscores the importance of a comprehensive evaluation in diagnosing and managing constrictive pericarditis.
To summarize, constrictive pericarditis exhibits a diverse range of etiologies, as evidenced by case series from tertiary care centers:
Accounts for 42 to 61 percent of cases.
Represents a significant contributor, ranging from 11 to 37 percent.
Contributes in 2 to 31 percent of cases, particularly after Hodgkin disease or breast cancer.
Occurs in 3 to 7 percent of cases.
Tuberculous or purulent pericarditis contributes to 3 to 15 percent of cases.
Malignancy, trauma, drug-induced factors, asbestosis, sarcoidosis, and uremic pericarditis collectively contribute to 1 to 10 percent of cases.
This variety in etiological factors highlights the importance of a comprehensive assessment when diagnosing and managing constrictive pericarditis.
Constrictive pericarditis poses a diagnostic challenge due to its diverse symptomatology, making reliance on clinical history alone nearly impractical. Patients often experience a gradual onset of symptoms over several years, rendering them unaware until prompted. These symptoms overlap with those of right-sided congestive heart failure (CHF), adding complexity to the diagnostic process. Dyspnea, universally present and frequently the initial symptom, is accompanied by fatigue, orthopnea, and manifestations such as lower-extremity edema, abdominal swelling, and discomfort. Nausea, vomiting, and right upper quadrant pain, when present, are attributed to hepatic or bowel congestion.
In the early stages, physical findings may be subtle, demanding meticulous examination to avoid overlooking the diagnosis. Advanced stages may manifest with significant illness features, including muscle wasting, cachexia, or jaundice. Noteworthy cardiovascular findings include elevated jugular venous pressures, sinus tachycardia, and an often impalpable apical impulse. The presence of a pericardial knock, indicative of sudden ventricular filling cessation, is notable, occurring along the left sternal border.
While a cardiac murmur is typically absent, pulsus paradoxus, if present, rarely exceeds 10 mm Hg. The Kussmaul sign, elevation of systemic venous pressures with inspiration, is a common but nonspecific finding. Gastrointestinal and pulmonary manifestations may include hepatomegaly, ascites, spider angiomata, palmar erythema, and dependent edema. Right-sided heart cardiac catheterization aids in direct assessment, revealing a characteristic ventricular pressure waveform and contributing to a comprehensive understanding of the condition. The interplay of clinical history and physical examination findings is crucial in navigating the diagnostic intricacies of constrictive pericarditis.
The evaluation of patients suspected of having constrictive pericarditis involves a comprehensive approach that includes clinical history, physical examination, and various diagnostic tests. The following key points summarize the diagnostic process:
Elevated plasma BNP is less common in constrictive pericarditis compared to other cardiomyopathies.
Timing is critical, with better results observed in early interventions, minimizing calcification and heart failure risk.
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