Introduction: Constrictive pericarditis is a pathology rarely found in current practice, of various etiologies, characterized by fibrosis and thickening or even calcification of the pericardium. These changes impair diastolic filling, with relative preservation of cardiac systolic function. A correct diagnosis is based primarily on high clinical suspicion and is difficult to establish on clinical signs alone, posing a challenge even for expe-rienced cardiologists. Confirmation by non-invasive multimodal imaging or cardiac catheterization is required. The main differential diagnosis should be made with restrictive cardiomyopathies. This is sometimes difficult to achieve, but of major importance, given the existence of potentially reversible causes of constrictive pericarditis. Among the more common etiologies are tuberculosis, various neoplasias, autoimmune diseases, radiotherapy of the chest or history of cardiac surgery.

Case presentation: 65 years old patient, known with grade II arterial hypertension, paroxysmal atrial fibrillation and dyslipidemia comes to the emergency department with dyspnea at rest, orthopnea and noc-turnal paroxysmal dyspnea of two weeks duration. Cli-nical examination reveals dyspnea at rest, with jugular vein distention, important peripheral edema and bilateral pleural fluid confirmed by chest X-ray. ECG at admission shows sinus tachycardia and nonspecific di-ffuse changes of the ST-T segment. Echocardiography shows constrictive pericarditis, with septal deviation and E/A ratio greater than 2. A chest CT is performed and shows calcification and thickening of the pericar-dium with a maximum thickness of 1.5cm. Thoracen-tesis is performed, showing clear fluid, high in proteins and LDH, low in glucose, with negative cultures. Coro-nary angiography reveals 50% lesion on the left main coronary artery. Given the need for high doses of di-uretic administered continuously to maintain euvole-mic status, pericardiectomy is scheduled with favorable postoperative evolution.

Particularity: The peculiarity of this case lies in the presentation of a constrictive pericarditis as acute heart failure with the predominance of right sided heart-failure in a previously asymptomatic patient. No infec-tious, autoimmune or malignant cause of constrictive pericarditis could be found. Also, 50% left main ste-nosis becomes significant in the context of pericardial constriction and impaired diastolic filling, posing spe-cific problems related to the surgical treatment of such a patient. Constrictive pericarditis is a rare pathology with inconsistent response to medical treatment, that requires treatment of the patient in a center experienced in cardiac surgery.