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Related Experiment Video

Updated: Jun 18, 2026

Electrocardiogram Recordings in Anesthetized Mice using Lead II

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Published on: June 20, 2020

[Medication associated long QT syndrome].

M Bruggisser¹, A Rätz Bravo, M Bodmer

¹Abteilung für Klinische Pharmakologie und Toxikologie und Regionales Pharmakovigilance Zentrum Basel.

|December 3, 2009

Summary

This summary is machine-generated.

A 76-year-old woman experienced fainting due to orthostatic syncope, likely triggered by the drug citalopram. Discontinuing citalopram promptly normalized her prolonged QT interval, preventing potential cardiac events.

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Area of Science:

Cardiology
Clinical Pharmacology

Background:

Orthostatic syncope is a common cause of fainting, particularly in older adults.
Drug-induced long QT syndrome (LQTS) is a serious condition that can lead to life-threatening ventricular arrhythmias.

Observation:

A 76-year-old woman presented with syncope and was found to have sinus bradycardia, hypokalemia, and a prolonged QT interval.
The prolonged QT interval resolved rapidly after discontinuation of citalopram.

Findings:

Citalopram was identified as the probable cause of the prolonged QT interval.
The patient's clinical presentation and recovery supported a diagnosis of orthostatic syncope, with drug-induced LQTS as a critical differential diagnosis.

Implications:

This case highlights the importance of considering drug-induced LQTS in patients with syncope and QT prolongation.
Awareness of citalopram's potential to prolong the QT interval is crucial for clinicians managing patients at risk for cardiac arrhythmias.