Keywords

Hypothyroidism, cardiac tamponade, pericardiocentesis, thyroxine

Hypothyroidism is a multisystem disease affecting various parts and altering various functions of the body. Even though the occurrence of pericardial effusion has been described in the previous literatures, the occurrence of tamponade in such patients is extremely rare. Diagnosis of tamponade in hypothyroid cases is difficult as it is overlooked due to the presence of features of heart failure like tachycardia, pedal edema and cardiomegaly in chest X-ray. Emergent action in the form of closed pericardiocentesis can ensure the stability and prognostic improvement in such patients along with the addition of thyroxine supplements.

Case Report

A 32-year-old male patient presented to the emergency department with history of breathlessness of 3 months duration aggravated since 7 days, easy fatigability and decreased exercise tolerance. Breathlessness was insidious in onset and gradually progressed over 3 months, it was present even at rest when he was admitted to the hospital. There was no history of palpitation or chest pain; neither was he a known case of hypertension or diabetes. The patient was treated at a peripheral center for anemia.

On examination, he was pale with puffiness of face and bilateral pitting type of pedal edema. His pulse was 90 bpm, low volume, feeble and regular. In addition, pulsus paradoxus was present. Blood pressure was 80/50 mmHg. His oxygen saturation was 91% at room air. Respiratory rate was 30 cycles/min. Cardiovascular system examination revealed raised jugular venous pressure (JVP) of about 12 cm above sternal margin. Heart sounds were muffled. He had delayed deep tendon reflexes, hoarseness of voice, delayed speech. Other systemic examination was within normal limits. His random blood sugar was 120 mg%, hemoglobin of 11.2 mg%. Renal and liver parameters were within normal limits. Electrocardiogram (ECG) revealed low voltage complexes (Fig. 1). Chest X-ray showed cardiomegaly with typical money bag appearance (Fig. 2). Two-dimensional echocardiography showed the presence of early diastolic collapse of right ventricle and a large pericardial effusion, suggestive of cardiac tamponade (Fig. 3).

In the view of worsening of general condition; emergency therapeutic closed pericardiocentesis was performed and about 1.6 liters of serous fluid was drained. Analysis of pericardial fluid revealed proteins of 4.8 g/dL, sugar of 50 mg/dL, cytology was negative for malignant cells, culture yielded no growth, negative for acid-fast bacilli and Gram staining, lipase of 27.23 IU/L, amylase of 51 IU/L, cholesterol of 121 mg/dL and adenosine deaminase levels of 18 IU/L. Test for collagen vascular markers were normal.

After therapeutic pericardiocentesis, his general condition improved and thyroid function test results came and were as follows: Tri-iodothyronine (T3)-0.25 ng/mL, thyroxine (T4)-1.80 µg/dL, thyroid-stimulating hormone (TSH)-2.11 µIU/mL, free T3 (FT3)-<1 pg/mL, FT4-0.40 ng/dL. Patient was started with thyroxine supplements and advised to follow-up after a month. Follow-up general condition was satisfactory and 2D echocardiography confirmed that patient did not develop further fluid accumulation.

Discussion

The occurrence of a pericardial effusion due to hypothyroidism seems to be related to the severity and duration of the disease. The incidence is reported to be as low as 3% in early mild stage to as high as 80% when myxedema is present.¹ Cardiac tamponade is usually a dreadful consequence of increased pericardial pressure with accumulation of pericardial fluid within the pericardial sac that may be caused by acute pericarditis, tumor, uremia, hypothyroidism, trauma, cardiac surgery or other inflammatory/noninflammatory conditions.² Cardiac tamponade in patients diagnosed with hypothyroidism is probably rare as it is due to pericardial distensability and the slow accumulation of fluid, allowing significant fluid accumulation without hemodynamic compromise. It is important to suspect cardiac tamponade when patients have hemodynamic compromise regardless of the amount of pericardial effusion.³ For patients diagnosed with cardiac tamponade without sinus tachycardia, hypothyroidism should be suspected.⁴

The pathophysiologic derangements responsible for the collection of fluid in the serous cavities of hypothyroid patients are probably increased systemic capillary permeability and disturbances in electrolyte metabolism.⁵ Alexander first used the term “Gold Paint Effusion” to describe the golden brown appearance of the pericardial fluid due to the shimmering satin cholesterol crystals. The high cholesterol content of the fluid has been attributed to disturbances in lipid metabolism; possibly, a churning action of the heart plays a role in the precipitation of cholesterol from pericardial fluid or the poor absorptive capacity of the pericardium may be a major factor.^3,5,6 Thyroid replacement alone is sufficient for resolution of these effusions, although it may take many months.

In our case, patient generally improved with symptoms and there was no further accumulation of serous fluid within pericardium in the subsequent follow-up examinations. Pericardiocentesis is indicated only if cardiac tamponade develops.

This rare but significant condition should be considered, especially when it occurs after acute cold exposure. Pericardial effusion, lipid metabolic abnormality and abnormal liver function can be easily reversed with thyroid replacement.^7-9

Conclusion

Hypothyroidism should be suspected and evaluated in a case of cardiac tamponade when there is relative bradycardia, high TSH, low thyroid hormones since tamponade itself might be the only presenting feature. A physician needs to familiarize themselves with this presentation as a part of their workup for early diagnosis, which is important for improving the management aspect and outcome.

References

1. Hardisty CA, Naik DR, Munro DS. Pericardial effusion in hypothyroidism. Clin Endocrinol (Oxf). 1980;13(4):349-54.
2. Saito Y, Donohue A, Attai S, Vahdat A, Brar R, Handapangoda I, et al. The syndrome of cardiac tamponade with “small” pericardial effusion. Echocardiography. 2008;25(3):321-7.
3. Retnam VJ, Chichgar JA, Patkar LA, Chikhalikar AA, Golwalla AF. Myxedema and pericardial effusion with cardiac tamponade (a case report). J Postgrad Med. 1983;29(3):188-190B.
4. Wang JL, Hsieh MJ, Lee CH, Chen CC, Hsieh IC, Lin JD, et al. Hypothyroid cardiac tamponade: clinical features, electrocardiography, pericardial fluid and management. Am J Med Sci. 2010;340(4):276-81.
5. Chou SL, Chern CH, How CK, Wang LM, Huang CI, Lee CH. A rare case of massive pericardial effusion secondary to hypothyroidism. J Emerg Med. 2005;28(3):293-6.
6. Usalan C, Atalar E, Vural FK. Pericardial tamponade in a 65-year-old woman. Postgrad Med J. 1999;75(881):183-4.
7. Chatterji A. An unusual cause of pericardial tamponade. Scott Med J. 2009;54(1):58.
8. Lin CT, Liu CJ, Lin TK, Chen CW, Chen BC, Lin CL. Myxedema associated with cardiac tamponade. Jpn Heart J.2003;44(3):447-50.
9. Al-Mahroos HM, Al-Bannay RA. Massive pericardial effusion as a sole manifestation of hypothyroidism: a case report. Bahrain Med Bull. 2000;22(4):188-91.