This patient requires no further intervention at this time. She developed a wide complex rhythm shortly after percutaneous coronary intervention and reperfusion of her infarct-related artery. The electrocardiogram (ECG) shows a regular wide complex rhythm at 92/min with no clearly discernible atrial activity, findings consistent with accelerated idioventricular rhythm (AIVR). AIVR is postulated to result from abnormal automaticity in the subendocardial Purkinje fibers. It is observed in up to 15% of patients who undergo reperfusion of an infarct-related artery. The rate is almost always less than 120/min and usually less than 100/min. Most studies have shown that it is a benign rhythm when it occurs within 24 hours of reperfusion. This patient is tolerating the rhythm well and is already on a β-blocker for post–myocardial infarction care; therefore, no intervention is required.

Neither amiodarone nor lidocaine is indicated because AIVR is a benign ventricular arrhythmia and usually does not recur. Studies of prophylactic lidocaine after acute coronary syndromes have demonstrated potential harm, and amiodarone has been associated with decreased survival after myocardial infarction.

Cardioversion is not indicated because AIVR is a transient rhythm and, in this patient, it is well-tolerated.

AIVR usually indicates successful (or at least partial) reperfusion and is considered a reversible arrhythmia. Implantable cardioverter-defibrillator (ICD) placement is not indicated at this time given the patient's recent revascularization and nature of the arrhythmia. If the left ventricular ejection fraction remains low despite medical therapy, ICD placement might be indicated in the future.