Radiofrequency ablation of right-sided accessory pathways in pediatric patients

Asymptomatic Wolff-Parkinson-White Syndrome: An Ounce of Prevention Is Worth the Risk of Cure

PURPOSE OF REVIEW

With increased electrocardiogram screening, asymptomatic preexcitation has become more prevalent. Historically, the asymptomatic-symptomatic dichotomy has directed management. This approach warrants scrutiny, as asymptomatic Wolff-Parkinson-White (WPW) syndrome is not without risk. Children may be unreliable symptom reporters, have atypical arrhythmia symptoms, yet have years to become symptomatic.

RECENT FINDINGS

In a large WPW study, symptomatic patients were more likely to undergo ablation than asymptomatic patients, yet, except for symptoms, there were no differences in clinical or electrophysiology study (EPS) characteristics. Present data confirm real risk in asymptomatic WPW-sudden death can be the first symptom. Although malignant arrhythmias correlate better with EPS risk stratification than with symptoms, EPS data are imperfect predictors. Unlike adults with WPW, children have yet to prove survivorship. Asymptomatic children must be treated differently than adults. Sudden death risk is low but front-loaded in the young. An aggressive approach to asymptomatic WPW is warranted in this era of highly successful, low-risk catheter ablations.

Electroanatomic mapping of the right coronary artery: a novel approach to ablation of right free-wall accessory pathways

BACKGROUND

Catheter ablation of right free-wall (RFW) accessory pathways continues to be associated with lower success and higher recurrence rates compared with other pathway locations. Reliably identifying the precise location of RFW accessory pathways often contributes to the difficulty in ablating these pathways. Improved localization of RFW accessory pathways has been described utilizing multielectrode right coronary artery (RCA) catheterization. This approach has not been widely adopted, in part due to concerns of prolonged catheter placement within the RCA. We describe the technique of creating a 3-D electroanatomic map of the right atrioventricular groove, limiting the duration of a microcatheter within the RCA, to facilitate ablation of RFW accessory pathways.

METHODS AND RESULTS

Following intracardiac identification of a RFW accessory pathway, an octapolar microcatheter was placed in the RCA. A 3-D electroanatomic map of the RCA was created during retrograde accessory pathway conduction using ventricular pacing. Immediately following creation of the map, the RCA catheter was removed. Endocardial mapping and ablation of the RFW accessory pathway was performed using the RCA electroanatomic map as a guide. This technique was used in four pediatric patients. The microcatheter was within the RCA for less than 1 min in all patients. Radiofrequency catheter ablation of the RFW accessory pathways were successfully performed with two lesions. There were no complications or recurrences at follow-up.

CONCLUSIONS

The creation of a 3-D electroanantomic map of the RCA effectively localizes RFW accessory pathways and facilitates successful ablation. This technique minimizes the duration of RCA instrumentation.