Prospective National Audit of the Anesthetic Management of Children With Long QT Syndrome

It is recognized that the perioperative anesthetic management of children with long QT syndrome may be complex, as they are at risk of life-threatening arrhythmias such as ventricular tachycardia, torsades des pointes, ventricular fibrillation, or severe bradycardia. There is uncertainty regarding the incidence of complications as well as which techniques might be acceptable or preferable in this group of patients.

In collaboration with the Congenital Cardiac Anesthesia Network, we conducted a prospective audit of the anesthetic management, complications, and outcomes of children with long QT syndrome.

Following receipt of ethics committee approval and an extensive process of communication within the Congenital Cardiac Anesthesia Network and elsewhere, over approximately a two-year period in the United Kingdom we prospectively collected fully anonymized data relating to the anesthetic management of children with long QT syndrome using an online secure reporting portal.

90 episodes of anesthesia for cardiac/cardiological (44) and non-cardiac (46) procedures were reported in 81 patients, with a median age of 6 years and a median weight of 22 kg. 59% were male. In 57 patients (70%), the diagnosis of long QT syndrome had been confirmed by genotyping. Where available, the QTc on a preoperative ECG ranged from 340 to 650 milliseconds. 14 patients had a history of previous out-of-hospital cardiac arrest, and 18 patients had an in situ cardiac pacing/defibrillation system. Three patients had a previous history of major complications under anesthesia, including ventricular tachycardia or ventricular fibrillation. Three patients experienced a significant complication, including intermittent atrioventricular block, ventricular tachycardia, changes in QRS morphology on the electrocardiograph, and bradycardia necessitating cardiopulmonary resuscitation. Both intravenous and inhalational agents were used perioperatively. No patient required unplanned admission to an intensive care unit. In every case, the patient was anesthetized by a consultant.

This complex group of patients has a significant complication rate under general anesthesia. Perioperative management of such patients should be delivered by experienced anesthetists, and in the majority of cases, it is appropriate for this to take place in centers where there is relevant additional cardiological expertise.