SHM Converge Scientific Abstract ePoster Gallery-A Perfect Storm: A Case of Methadone-Associated QTC Prolongation Leading to Torsades De Pointes

Pdf Summary

This case report describes a 57-year-old man with opioid use disorder and chronic pain who developed torsades de pointes (TdP) from severe QTc prolongation while taking high-dose methadone. He had been switched from buprenorphine to methadone about six months earlier, and his dose was increased to 150 mg daily without repeat ECG monitoring. He was also taking sertraline and had recently started ondansetron, both of which can contribute to QT prolongation.<br /><br />He presented to the emergency department with dizziness, shortness of breath, and nausea. Initial labs showed hypokalemia and low-normal magnesium. His ECG revealed marked QTc prolongation to 669 ms. While on telemetry, he developed nonsustained ventricular tachycardia that progressed to torsades de pointes, resulting in cardiac arrest. He received ACLS and achieved return of spontaneous circulation. Workup did not show evidence of structural heart disease or ischemia.<br /><br />The authors attribute the arrhythmia to a “perfect storm” of risk factors: high-dose methadone, additional QT-prolonging medications, and electrolyte abnormalities. The report emphasizes that methadone is well known to prolong QTc, especially at doses above 120 mg/day, and that ECG monitoring is recommended during titration. Current guidelines suggest repeat ECGs at 30–40 mg/day and again at 100 mg/day, along with careful review of other QT-prolonging drugs and metabolic risk factors.<br /><br />The patient was advised to switch back to buprenorphine but declined due to concerns about pain control. Instead, he was tapered to a lower methadone dose, changed to a non-QT-prolonging SSRI, and told to avoid other QT-prolonging agents. His QTc normalized to 445 ms before discharge. The case highlights the importance of vigilant monitoring and medication review to reduce TdP risk in patients receiving methadone.

Asset Subtitle

Tyler Cho

Meta Tag

Author List Phillip Hamilton, Tyler Cho

Category Clinical Vignettes

Concept Torsades de Pointes

Concept Antipsychotic-Induced QT Prolongation

Concept Methadone

Concept Electrocardiogram

Concept Hypokalemia

Distinguished Non-Finalist

Presenter Organization The Ohio State University Wexner Medical Center

Presenting Author Tyler Cho

Track Adult

Keywords

methadone

torsades de pointes

QTc prolongation

ventricular tachycardia

cardiac arrest

opioid use disorder

electrolyte abnormalities

sertraline

ondansetron

ECG monitoring

Torsades de Pointes

Antipsychotic-Induced QT Prolongation

Methadone

Electrocardiogram

Hypokalemia