Lynn Nappo

Reducing patient radiation dosage during pediatric SVT ablations using an "ALARA" radiation reduction protocol in the modern fluoroscopic era.

Ablation for supraventricular tachycardia (SVT) relies upon fluoroscopy (fluoro), which exposes the patient and staff to ionizing radiation. The objective of this work was to present a new “ALARA—As Low As Reasonably Achievable” protocol with alterations to fluoroscopic x‐ray parameters to reduce dose without an electroanatomical (EAM) approach.

A Transbaffle Approach to Ablation in a Child with an Extracardiac Fontan

We present the case of an 11‐year‐old with D‐transposition, double inlet left ventricle, and dextrocardia 8 years following an extracardiac Fontan with supraventricular tachycardia mediated by a concealed accessory pathway. A transbaffle puncture was performed with fluoroscopic and transesophageal echocardiography guidance and the pathway location as well as its proximity to the HIS bundle were identified. The pathway was successfully ablated and the patient is asymptomatic for 12 months postablation. (PACE 2010; 33:368–371)

Characteristics of ventricular tachycardia arising from the inflow region of the right ventricle.

INTRODUCTION Ventricular tachycardia (VT) arising from the right ventricular inflow (RVI) region is uncommon. There is minimal literature on the clinical and electrocardiographic characteristics of RVI VT. METHODS A retrospective analysis of patients with RVI VT who underwent electrophysiology study between 2006 and 2011 was performed. Patients with structural heart disease (including arrhythmogenic right ventricular dysplasia) were excluded. RESULTS Seventy patients underwent an electrophysiology study for VT arising from the right ventricle during the study period. Nine patients (13%) met the inclusion criteria for RVI VT and were the subject of this analysis. The median age was 46 years (range, 14-71), and VT cycle length was 295 milliseconds (range, 279-400 milliseconds). All VTs had an left bundle-branch block morphology. An inferiorly directed QRS axis was noted in 7 (78%) of 9 patients and a left superior axis in 2 (22%) of 9 patients. A QS or rS pattern was noted in all patients in aVR and V(1). A transition from S to R wave occurred in V(3) to V(5) in all patients, with 78% of the patients transitioning in V(4) or V(5). Ablation was attempted in 8 (89%) of 9 patients and was successful in 6 (67%) of 9 patients. Ablation was limited in all unsuccessful patients due to the proximity to the His and risk of complete heart block. CONCLUSIONS Electrocardiographic findings of a left bundle-branch block with a normal QRS axis, QS or rS patterns in aVR and V(1), and late S to R transition (V(4)/V(5)) are commonly found in RVI VT. Because of the proximity to the His, ablation of RVI VT may be more challenging than that of right ventricular outflow tract VT.

Novel method of signal analysis for ablation of Wolff-Parkinson-White syndrome

BACKGROUND Identification of the site of successful radiofrequency catheter ablation (RFCA) for Wolff-Parkinson-White (WPW) syndrome may be subjective. OBJECTIVE The purpose of this study was to develop an automated signal analysis program to predict a successful ablation site. METHODS Patients who underwent successful RFCA for WPW from 2008- 2010 at our center were analyzed. Inclusion criteria were age <21 years, loss of preexcitation in <5 seconds, and sustained success at 3 months. Exclusion criteria were congenital heart disease and pacing during RFCA. The standard recording system signal was filtered into low frequency (LF 0-≤0.02 Hz) and high frequency (HF >0.02-≤0.45 Hz). Software identified the beginning of the HF signal, LF and R-wave peaks, LF/HF signal amplitude, and area under the HF/LF signals. Successful and unsuccessful (radiofrequency energy applied without accessory pathway block) signals were compared. RESULTS Thirty patients were analyzed; 16 had both successful and unsuccessful signals, and 14 had a successful ablation with 1 radiofrequency application. Mean age was 13.7 ± 3.1 years, weight 54.9 ± 22.4 kg, and time to accessory pathway ablation 1.7 ± 1.4 seconds. Significant differences were found between successful and unsuccessful signals in area under HF signal, LF amplitude, LF to R time, HF ratio, and HF area × HF ratio. A receiver operating curve of HF area × HF ratio produced an area under the curve of 0.89. An HF area × HF ratio of 3.1 distinguished successful from unsuccessful signals with 100% specificity and 81% sensitivity. CONCLUSION Automated signal analysis retrospectively differentiated successful from unsuccessful signals in patients undergoing RFCA for WPW. This software may improve the safety and efficacy of RFCA in children.

The “hidden” concealed left-sided accessory pathway: An uncommon cause of SVT in young people

Concealed left‐sided accessory pathways (CLAP) are a cause of supraventricular tachycardia (SVT) in the young. Most are mapped with right ventricular (RV) apical/outflow pacing. Rarely, alternative means of mapping are required. We review our experience from three pediatric electrophysiology (EP) centers with a rare form of “hidden” CLAP.

A multicenter review of ablation in the aortic cusps in young people

Ablation within the aortic cusp is safe and effective in adults. There are little data on aortic cusp ablation in the pediatric literature. We investigated the safety and efficacy of aortic cusp ablation in young patients.

THE PREVALENCE OF ARRHYTHMIAS DURING EXERCISE TESTING IN CHILDREN

Exercise testing is commonly performed in children for evaluation of cardiac disease. There are few data on the prevalence and types of arrhythmias observed during exercise testing in children. A retrospective review of all patients < 21 years of age undergoing exercise testing at our center from

A COST-EFFECTIVE APPROACH TO RADIOFREQUENCY CATHETER ABLATION OF LEFT-SIDED ACCESSORY PATHWAYS IN YOUNG PATIENTS WITH WOLFF-PARKINSON-WHITE SYNDROME: A NOVEL THREE CATHETER TECHNIQUE

Ablation is the treatment of choice for WPW in children. With increased concern regarding healthcare costs, efforts to reduce cost while maintaining quality are paramount. We present a novel 3-catheter approach to the ablation of left-sided accessory pathways (AP) in children with WPW. A