Disorders of the pericardium are commonly associated with
pericardial effusion. Its etiology comprises a broad spectrum of diseases including also
malignancies. Pericardiocentesis, pericardioscopy and targeted epicardial biopsy with consecutive pericardial fluid and epicardial biopsy analysis by cytology, molecular biology and immunology establish the underlying etiology in the majority of cases. Of particular therapeutic and prognostic importance is the definite differentiation of malignant
pericardial effusion from benign
pericardial effusion.
Biomarkers for
cardiovascular diseases can be divided into biochemical, histological, immunologic, serologic and molecular markers as well as imaging
biomarkers.
Biomarkers have proven to be useful in the diagnosis, differential diagnosis and prognosis of
ischemic heart disease and
heart failure. With respect to pericardial disorders, a comprehensive approach combining clinical information, imaging
biomarkers,
biomarkers of
pericardial effusion and analysis of epicardial biopsies often leads to the definite etiologic diagnosis of
pericardial effusion. Computed tomography and magnetic resonance imaging allow further characterization of the effusion and, of note, also of the surrounding tissue, which is of particular interest in case of
malignancies.
Biomarkers of
pericardial effusion include
biochemical markers,
autoantibodies,
tumor markers, and
cytokines. Analysis of pericardial fluid specific gravity,
protein level and
lactate dehydrogenase (LDH) separates transudates from exsudates. High
adenosine deaminase levels (ADA) and low levels of
carcinoembryonic antigen (CEA) in the
pericardial effusion are observed in
tuberculous pericarditis allowing the differentiation from malignant
pericardial effusion. Additional markers, such as
interferon and
lysozyme, have also been suggested for the diagnosis of
tuberculous pericarditis.
Tumor markers in pericardial fluid have been used to diagnose malignant
pericarditis. CEA levels are significantly higher in malignant than benign effusion. By a cutoff level of CEA > 5 ng/ml the diagnostic sensitivity and specificity are 75% and 100%, respectively, in the diagnosis of malignant
pericardial effusion. Further analysis of
cytokines and mediators, serologic, immunologic and inflammatory markers may help to understand the pathophysiology of the pericardial disease and provide useful diagnostic information.