Torsade de pointe. Report of 18 cases

Area of Science:

• Cardiology
• Electrophysiology

Background:

• Torsade de pointe (TdP) is a life-threatening ventricular arrhythmia associated with a prolonged QT interval.
• Understanding the underlying causes and precipitating factors of TdP is critical for effective management.

Purpose of the Study:

• To investigate the factors contributing to the development of TdP in patients with long QT interval.
• To compare the characteristics and management of TdP based on its underlying cause.

Main Methods:

• Retrospective analysis of 18 patients with recurrent TdP and prolonged QT interval.
• Evaluation of patient history, ECG findings, underlying cardiac conditions, and response to interventions.

Main Results:

• Antiarrhythmic drugs were the most common cause (55.5%), followed by complete heart block (33.5%).
• Drug-induced TdP showed moderate QT prolongation, frequent hypokalemia, and bradycardia.
• Heart block-induced TdP presented with marked QT prolongation, very slow heart rates, and less frequent hypokalemia.
• A long-short sequence initiated TdP in 83% of observed episodes.
• Drug withdrawal or correction of the cause was effective; isoproterenol and ventricular pacing were beneficial.

Conclusions:

• Identifying the precipitating factor is essential for TdP management.
• Treatment strategies should be tailored to the underlying cause, with drug cessation or correction of reversible factors being primary.
• Lidocaine was often ineffective or detrimental, while cardioversion required repeated application.