Cardiac Amyloidosis: A Rare Cause of Recurrent Chylothorax

Amyloidosis is caused by the extracellular deposition of fibrils composed of low molecular weight protein subunits. Its two main types are amyloid light chain (AL) amyloidosis and amyloid A (AA) amyloidosis (previously referred to as secondary amyloidosis). Clinical manifestations are dependent upon location, type, and amount of deposit. We report a case of a 72-year-old female who presented to the emergency department for evaluation of cough, fatigue, and shortness of breath. Physical examination was notable for decreased breath sounds bilaterally over the lower lung fields. Computed tomography (CT) of the chest showed a large lobulated right pleural effusion and atelectasis. Two liters of milky, white pleural fluid was removed via thoracocentesis, and pleural fluid analysis was consistent with chylothorax. Over the next 10-day period, there was a reaccumulation of the pleural fluid, which required a pleural catheter placement. The patient underwent video-assisted thoracoscopic surgery with pleural and pericardial tissue biopsy that was consistent with kappa or lambda AL amyloid. Unfortunately, her respiratory status subsequently declined, requiring mechanical ventilation, and eventually leading to cardiac arrest. Cardiac amyloidosis can rarely cause chylous ascites and chylothorax. The absence of electrocardiographic findings of left ventricular hypertrophy combined with apparent left ventricular hypertrophy on echocardiography is strongly suggestive of infiltrative cardiomyopathy such as cardiac amyloidosis. In these cases, cardiac amyloidosis should be considered in the differential diagnosis of chylothorax.