A Case Report on QTc Prolongation: Understanding the Medication Risks and Electrolyte Imbalance

Prolonged QTc interval is one of the critical risk factors for sudden cardiac death. We all know that sudden cardiac death is often caused by acute onset ventricular arrhythmia, and QTc prolongation is one of the potential risk factors. It can be congenital or acquired. The acquired ones are commonly witnessed in day-to-day clinical practice. Several classes of mediations are well known to cause these conditions. Among many antiarrhythmic agents, especially amiodarone, is a critical drug to be monitored, as it strongly potentiates QTc prolongation. Especially in combination with metabolic abnormalities, this abnormality can occur rapidly with notable clinical presentation. This case report elicits an interesting clinical scenario in which a 79-year-old pleasant lady with multiple comorbidities presents with a syncopal episode. Missing the cardiologist’s appointment for dose adjustments of her medication, amiodarone was noteworthy. Also, an acute electrolyte imbalance from the possibly recent use of diuretics aggravated the clinical situation. On presentation, the electrocardiogram showed a remarkably prolonged QTc, which was way more compared to the prior ones available. Discontinuation of amiodarone and repletion of the electrolytes brought down the QTc interval to almost a normal range and no syncopal episode within two days. Hence, understanding the medications’ potential risks and having a close watch on the possible side effects is key to avoiding dreadful complications of arrhythmia and sudden cardiac death from the same. This case report cumulatively covers this essential medical knowledge and practical, vital points.