Idiopathic bilateral chylothorax associated with chylopericardium is an exceptionally rare clinical entity in adults. We present the case of a 32-year-old female admitted with progressive dyspnea, cardiac tamponade, and bilateral pleural effusions. Pericardial and pleural drainage yielded chylous fluid with triglyceride levels >200 mg/dL. Conservative management with fasting and total parenteral nutrition failed after three weeks. Advanced lymphatic imaging, including lymphangiography, demonstrated a defect at the thoracic duct crossing. The patient underwent successful thoracoscopic thoracic duct ligation with complete resolution of both pleural and pericardial effusions and excellent postoperative recovery. This case highlights the diagnostic value of lymphatic imaging and supports minimally invasive thoracic duct ligation as a definitive treatment strategy in refractory chylous effusions.

Keywords: chylothorax, chylopericardium, thoracic duct ligation, thoracoscopy, minimally invasive surgery, lymphangiography.