SAT-484 Presyncope as Initial Presentation of Massive Pericardial Effusion with Tamponade in a Patient with Primary Hypothyroidism

Presyncope as initial presentation of massive pericardial effusion with tamponade in a patient with primary hypothyroidism Background: Hypothyroidism is an endocrinologic disorder that affects multiple systems ranging from cardiovascular, central nervous system, musculoskeletal, etc. One of the possible cardiovascular complications of hypothyroidism is pericardial effusion which is only rarely associated with tamponade. In this case report we have a 49 years old woman who presented with impending pericardial tamponade secondary to chronic primary hypothyroidism. Clinical case: A 49 years old woman with history of hypothyroidism presented to the hospital on account of headache, dizziness with presyncope episode, generalized weakness and shortness of breath for 7 days, physical exam showed normal vital signs, distant heart sounds, laboratory tests showed TSH:29.5 uIU/mL (normal range 0.270- 0.4200 uIU/mL), fT4: <0.1ng/dL (normal range 0.9–1.8 ng/dL), fT3: 1.68 pg/mL (normal range 1.80–4.60 pg/mL. Electrocardiogram showed low voltage QRS, chest CT showed large pericardial effusion with findings suggestive of right heart failure, Echocardiogram showed left ventricular dysfunction and large pericardial effusion. The patient was taken to the operating room for emergent pericardial window creation with pericardiectomy and was admitted to the Cardiac Care Unit for management of tamponade status post pericardial window. Levothyroxine 150 mcg, Liothyronine 25 mcg and Hydrocortisone 50 mg were started, the steroid was discontinued after adrenal insufficiency was ruled out. The pericardial drain was removed after 8 days and repeated tests showed TSH: 13.1 uIU/mL, fT3: 3.37 pg/mL, fT4: 0.5 ng/dL, studies of pericardial fluid only showed polymorphonuclear cells. The patient’s symptoms resolved and she was discharged on Levothyroxine 150 mcg and Liothyronine 25 mcg. During follow up visits the thyroid function tests were normal, Liothyronine was discontinued and a repeated Echocardiogram showed normal systolic function. Conclusions: Pericardial effusion can be found in 3–30% of patients with hypothyroidism but only in very rare cases (less than 3%) is associated with cardiac tamponade and occurs when there is a severe underlying condition like myxedema coma or prolonged untreated hypothyroidism (1). It is important not to miss that dizziness and presyncope in a patient with hypothyroidism may be a manifestation of cardiac tamponade. Once the diagnosis of hypothyroidism is made it is imperative to start treatment early as untreated hypothyroidism can cause severe cardiovascular complications but even when such are present, they can be reversible with thyroid replacement therapy. Reference: (1) Kahaly, G. and Dillmann, W. (2005). Thyroid Hormone Action in the Heart. Available at: https://academic.oup.com/edrv/article/26/5/704/2355198 [Accessed July 12 2019].