[Psychopharmaceuticals and arrhythmias]

Area of Science:

• Pharmacology
• Cardiology
• Psychiatry

Background:

• Psychoactive drugs have a known association with cardiac arrhythmias for decades.
• Torsades de pointes (TdP) was initially linked to pre-existing heart conditions or intoxication.
• Increasing recognition of non-cardiac drugs impacting cardiac repolarization and causing ventricular tachycardia.

Purpose of the Study:

• To review the association between psychoactive drugs and cardiac arrhythmias.
• To highlight the mechanisms by which these drugs affect cardiac repolarization, particularly QT-interval prolongation.
• To assess the arrhythmia risk associated with different classes of psychoactive medications.

Main Methods:

• Literature review of studies on psychoactive drugs and cardiac arrhythmias.
• Analysis of drug mechanisms affecting the potassium channel Ikr and QT-interval.
• Categorization of psychoactive drugs based on their reported association with arrhythmia risk.

Main Results:

• Low-potency phenothiazines, especially thioridazine, are frequently implicated in serious arrhythmias.
• High-potency phenothiazines and butyrophenones have fewer reported arrhythmia events.
• Atypical antipsychotics generally show a low risk of arrhythmic events despite some QT-interval prolongation.
• Tricyclic antidepressants are not recommended post-myocardial infarction; SSRIs appear safe.
• Drug interactions significantly contribute to fatalities involving QT-prolonging drugs.

Conclusions:

• Psychoactive drugs can induce significant cardiac repolarization abnormalities and arrhythmias.
• Risk stratification is crucial, especially for patients with pre-existing QT prolongation or TdP history.
• Careful consideration of drug interactions is vital to prevent fatal arrhythmic events.