Summary

We report a patient who presented to our hospital with unusual symptoms of non-specific complaints and uncontrolled hypertension. Acute cardiac tamponade was suspected from cardiomegaly on routine chest x-ray and confirmed with an echocardiogram. Analysis of the pericardial fluid and other laboratory data ruled out all the common causes except for hypothyroidism as a cause of cardiac tamponade. Tamponade results from increased intrapericardial pressure caused by the accumulation of pericardial fluid. The rapidity of fluid accumulation is a greater factor in the development of tamponade than absolute volume of the effusion. Hypothyroidism is a well-known cause of pericardial effusion. However, tamponade rarely develops owing to a slow rate of accumulation of pericardial fluid. The treatment of hypothyroidic cardiac tamponade is different from other conditions. Thyroxine supplementation is all that is necessary. Rarely, pericardiocentesis is needed in a severely symptomatic patient.