333 MASSIVE PERICARDIAL EFFUSION IN HYPOTHYROIDISM: A CASE REPORT

Abstract

Abstract Chronic massive pericardial effusion (PE) without cardiac tamponade is relatively rare. Of all possible etiologies of PE, hypothyroidism is an uncommon one. We reported a case of a 75-year-old woman, admitted at E.R. with confusion and unresponsive status, with diffuse face and lower limb'swelling . First-level examinations were performed: blood gas analysis showed hypoxia, respiratory acidosis and severe anaemia; the EKG revealed slow atrial fibrillation with ventricular rate of approximately 40 bpm and low QRS voltages. Echocardiogram showed massive PE, without sings suggestive of cardiac tamponade. A CT-scan of the brain, chest and abdomen was performed to exclude major active bleeding or neoplastic formations, and confirmed the presence of massive PE. Eventually, the effusion was drained with a pigtail catheter through a sub-xiphoid approach. Meanwhile blood tests results revealed a TSH level of 115 mIU/L (normal range 0,28–4,3 mIU/L) and fT4 level of 0,4 ng/L (normal range 8,0–17,0 ng/L). Severe, previously unknown, hypothyroidism was then diagnosticated and specific treatment with L-thyroxine was started. PE formation in hypothyroidism is due to several pathophysiologic mechanisms that include increased capillary permeability, extravasation of hygroscopic mucopolysaccharides, increased volume of albumin distribution, reduced lymphatic drainage, along with an increase in salt and water retention. The fluid accumulation in the pericardial space is a slow, chronic process, leading to huge effusions with no cardiac tamponade. PE may represent a severe complication of hypothyroidism, which should be taken into account in the differential diagnosis of the underlying cause. Echocardiogram is the best diagnostic tool, able to provide useful information about location, volume and hemodynamic impact of the effusion. Pericardiocentesis is not normally required to establish an accurate etiological diagnosis, which in most cases can be obtained simply on the basis of the clinical history and simple blood tests. Treatment is aimed at targeting the specific cause, thus, in our case, replacing the missing hormone.