Refractory Torsades de Pointes Due to Dofetilide Overdose

Area of Science:

• Cardiology
• Clinical Pharmacology

Background:

• Dofetilide is a Class III antiarrhythmic used for cardiac arrhythmias.
• Antiarrhythmic drugs, including dofetilide, can prolong the QT interval, leading to bradycardia and Torsades de Pointes (TdP).

Observation:

• A rare case of intentional dofetilide overdose in a patient with multiple comorbidities is presented.
• The patient experienced refractory TdP lasting four days, necessitating extensive interventions beyond initial stabilization.

Findings:

• Both therapeutic and excessive dofetilide doses can induce TdP.
• Standard guidelines for TdP management (magnesium, electrolyte correction) may be insufficient in severe dofetilide overdose.
• Isoproterenol and dopamine were crucial in managing persistent TdP, serving as a bridge to overdrive pacing.

Implications:

• This case underscores the scarcity of data on managing prolonged dofetilide overdose and refractory TdP.
• Highlights the potential need for advanced interventions like isoproterenol and dopamine in severe cases.
• Emphasizes the importance of continuous monitoring and tailored treatment strategies for dofetilide toxicity.