Case history:
Question: What are the cardiac implications of untreated
hypothyroidism?
Answer: We present a case of pericardial effusion from primary
hypothyroidism.
A 70-year-old female with a history of chronic obstructive pulmonary
disease (COPD), chronic arthritis with no documented hypothyroidism
presented to the emergency department with dyspnea evolving over the
last month, generalized weakness, and arthritic pain. Initial vitals,
were notable for bradycardia and hypoxia, with an oxygen saturation of
80% necessitating supplemental oxygen. She was awake, appeared frail,
and was not in acute distress. The exam revealed muffled heart sounds,
jugular venous distension, and features consistent generalized myxedema
(figure 1). Initial workup revealed pancytopenia with macrocytosis and
an unremarkable chemistry panel with a brain natriuretic peptide (BNP)
of 133.4 PG/ML. Imaging revealed cardiomegaly and pulmonary congestion
on chest radiography (figure 2), while computerized tomography (CT)
chest with contrast revealed a moderate to large pericardial effusion
(figure 3). Thyroid-stimulating hormone (TSH) was 102.94 UIU/ML (normal
range 0.30-5.50 UIU/ML) with a free T4 less than 0.1
NG/DL (normal range 0.9-1.8 NG/DL). A transthoracic echocardiogram
confirmed a sizable pericardial effusion without tamponade physiology
and severe concentric left ventricular hypertrophy (figure 4). She was
started on high dose intravenous levothyroxine and hydrocortisone. She
was discharged on an oral course of levothyroxine with close follow-up
with a cardiologist.