Severe primary hypothyroidism presenting with torsades de pointes.

Area of Science:

• Cardiology
• Endocrinology

Background:

• Transient loss of consciousness and cardiac arrhythmias can have diverse etiologies.
• Prolonged QT interval and torsades de pointes are serious conditions requiring urgent investigation.

Observation:

• An 85-year-old female presented with recurrent syncope, junctional bradycardia, and QT prolongation.
• Telemetry documented episodes of torsades de pointes despite initial management with drug withdrawal and electrolyte correction.

Findings:

• Severe primary hypothyroidism was identified as the underlying cause of bradycardia and QT prolongation.
• Treatment with levothyroxine and a permanent pacemaker resolved the arrhythmia and prevented recurrence.

Implications:

• This case highlights the critical link between severe hypothyroidism and potentially fatal cardiac arrhythmias.
• Endocrine evaluation should be considered in patients with unexplained bradycardia and QT prolongation.
• Management requires addressing both the underlying endocrine disorder and the cardiac manifestations.