Tuberculosis remains a major public health issue in Morocco. Pulmonary tuberculosis is the most common form, but various extrapulmonary forms exist. Tuberculous pericarditis is a rare form of extrapulmonary tuberculosis that can be complicated by cardiac tamponade, pericardial constriction or their combination, which can threaten the patient's life. Its clinical and radiological signs are nonspecific, and the clinical presentation can be misleading and incomplete, sometimes even with an initial tamponade. We report the case of a 68-year-old female patient admitted for intense retrosternal chest pain associated with acute dyspnoea, evolving in the context of unquantified weight loss and general deterioration. Additionally, she reported a history of fever and night sweats. Clinical examination revealed a conscious, febrile, hypotensive, tachycardic, polypneic patient with good oxygen saturation, signs of right heart failure and muffled heart sounds on auscultation. Chest X-ray revealed cardiomegaly, and the ECG showed diffuse low voltage. Given the presence of Beck's triad suggestive of cardiac tamponade, a transthoracic echocardiogram was performed, revealing a large pericardial effusion with a 'swinging heart'. A chest CT scan also confirmed the large pericardial effusion. The diagnosis of cardiac tamponade was made based on the clinical and radiological findings, and pericardial drainage was performed, after which the patient showed clinical improvement. PCR GenXpert MTB/RIF Ultra detected the presence of in the pericardial fluid, with no resistance to rifampicin. Culture was positive for . The diagnosis of tuberculous pericarditis was, thus, confirmed, and the patient was started on quadruple antituberculosis therapy with good clinical progress.