Case Presentation: A 44-year-old female with severe opioid use disorder (OUD) was admitted after a benzodiazepine withdrawal seizure. Her history was significant for methadone 165 mg daily dosing, anxiety managed with daily unprescribed benzodiazepines, and alcohol use disorder in remission. She had a prolonged QT interval, with a notable episode 18 months prior, when she suffered cardiac arrest from Torsades de Pointes (TdP) due to a QT of 640 ms. This was attributed to severe electrolyte abnormalities, alcohol withdrawal, and medication induced from methadone and ondansetron. During that hospitalization, electrophysiology was consulted and advised against implantable cardioverter defibrillator (ICD) placement, as the arrest was deemed related to reversible causes. She was started on buprenorphine, which was ineffective, leading to a restart of methadone with careful electrocardiogram monitoring in the outpatient setting. In her current admission upon arrival, her QT was 607 ms, leading to a temporary cessation of methadone. Shortly after, she experienced recurrent cardiac arrest from TdP, achieving resuscitation after one round of CPR. Electrophysiology and addiction medicine were consulted. Despite her history of two cardiac arrests, she expressed a strong desire to continue methadone, which she considered essential for managing her OUD. Given her ongoing risk for future TdP events, the multidisciplinary team offered and proceeded to implant a dual chamber ICD for secondary prevention. After the procedure, she was restarted on methadone and discharged on 120 mg daily, with close follow-up at her opioid treatment program (OTP). At her six-month ICD follow-up, she remained in early remission, with stable device interrogation and no adverse events.
Discussion: Methadone is a life-saving treatment for OUD, reducing mortality and overdose risk by up to 50%. However, it carries the risk of QT interval prolongation, especially at higher doses or in patients with other QT prolonging factors such as electrolyte derangements or in conjunction with other medications. The incidence of methadone associated QT prolongation is difficult to quantify due to variability in definitions and numerous risk factors. While QT prolongation is not uncommon among methadone users, the development of TdP remains rare. This risk may limit methadone use in OUD treatment. Clinicians often view methadone as a reversible cause of QT prolongation, which can lead to overlooking ICD considerations in this vulnerable population. Discontinuing methadone significantly increases the risk of relapse, overdose, and death. Existing case series indicate that ICDs can be lifesaving for patients continuing methadone therapy after TdP. In the fentanyl era, there is a need for individualized and patient-centered approaches in the treatment of OUD. This case highlights a thoughtful multidisciplinary discussion and shared decision making surrounding the consideration and placement of secondary prevention ICD in a patient with a history of TdP associated cardiac arrest who had previously failed buprenorphine therapy and had a strong desire to continue methadone therapy.
Conclusions: Methadone is an essential option for OUD treatment, effectively reducing mortality and overdose risks. Secondary prevention ICD should be thoughtfully considered and advocated for in patients with a history of TdP associated cardiac arrest who have previously failed buprenorphine therapy and have a strong preference to continue methadone therapy.