Evaluating the incidence of syncope and electrocardiogram changes in methadone-treated volunteers quitting addiction in yazd

Objectives: Methadone is a synthetic opioid with a high affinity for opioid receptors, widely used as an effective intervention for opioid dependence and the management of acute and chronic pain. However, its use has been associated with serious cardiac side effects, including torsades de pointes (TdP) and prolonged QTc intervals. This study investigated the incidence of syncope and electrocardiogram (ECG) changes in individuals who underwent methadone treatment for addiction. Methods: This cross-sectional study, conducted in Yazd in 2020, involved 100 participants seeking methadone treatment at an addiction clinic. A cardiologist recorded initial ECGs using a 12-lead ECG device, assessing parameters such as heart rhythm, QTc interval, and premature contractions. Participants were informed about the study procedures and the necessity of follow-up ECGs one week and three months after starting methadone. The researchers monitored the patients for three months with regular outpatient visits. Results: The findings revealed a significant difference in syncope incidence based on ECG rhythm on day seven and month three, with higher rates observed in patients exhibiting junctional rhythms or PVC (p-value=0.000). Additionally, a significant relationship was found between syncope frequency and U wave status at month three (p-value=0.046).No significant associations were noted for ST segment changes or T wave variations. Furthermore, higher methadone doses, longer QTc intervals on day seven, and prolonged PR intervals correlated with increased syncope occurrences. Conclusions: This study indicates that ECG-related variables and methadone dosage significantly influence syncope incidence among treated patients. Specifically, individuals with junctional rhythms or PVC and those receiving higher doses of methadone were at greater risk for syncope. Monitoring PR and QTc intervals is crucial for preventing syncope in patients undergoing methadone treatment.