RUDRA Registry (Real-World Clinical Registry for Patients With Recurrent Pericarditis)

Inclusion Criteria: 1. Men or women 18 years of age or older at the time of data recording or pericarditis debut; 2. Presence of one of the following conditions: * a specialist-confirmed diagnosis of recurrent pericarditis without an established etiology at the time of inclusion in the study (suspected "idiopathic recurrent pericarditis"); * a specialist-confirmed diagnosis of "idiopathic recurrent pericarditis". Exclusion Criteria: 1. Age below 18 years at the time of inclusion in the registry or debut of pericarditis; 2. Specialist-confirmed secondary genesis of RP (infectious, autoimmune, neoplastic, metabolic, traumatic, iatrogenic, etc.); 2. Manifestations and complications of myocarditis, various diseases of thoracic organs, systemic diseases, cardiac surgery, radiation therapy, tuberculosis, etc.); 3. lack of possibility of screening examination and dynamic follow-up; 4. Organ/tissue transplantation less than 5 years prior to study inclusion or debut of pericarditis; 5. Oncologic disease less than 3 years prior to study inclusion or pericarditis debut; 6. Chemotherapy with anthracycline-type drugs at the time of pericarditis debut; 7. Administration of amphetamine-type drugs at the time of pericarditis debut; 8. Cardiac/pericardial surgery in the last 6 months prior to study inclusion or pericarditis debut; 9. Myocardial infarction in the last 3 months prior to study inclusion or debut of pericarditis; 10. Traumatic chest injury in the last 3 months prior to study inclusion or pericarditis debut; 11. Absence of an informed consent form signed by the patient for participation in the study