Successful treatment with ivabradine for haemodynamically unstable junctional ectopic tachycardia occurring early after ST-elevation myocardial infarction.

Junctional ectopic tachycardia (JET) is a relatively uncommon arrhythmia predominantly observed in infancy, often occurring after congenital heart surgery. Although JET is rare in adults, it can occur in the presence of myocardial ischaemia. We describe a woman in her early 70s who presented with multivessel ST-segment elevation myocardial infarction and underwent percutaneous coronary intervention on left anterior descending artery and right coronary artery. She developed JET on the second day, resulting in haemodynamic compromise. Despite initial treatment attempts including amiodarone and beta-blocking agents proving insufficient in controlling JET, we successfully managed by administering ivabradine. Subsequently, she was discharged with recovered cardiac function without recurrence of JET. JET often proves refractory to multiple antiarrhythmic agents and can lead to unfavourable outcomes. Several case reports have demonstrated the effectiveness of ivabradine in treating JET during infancy, which can also be an effective therapeutic option for adult without adversely affecting haemodynamics.