Ripple mapping: A precise tool for atrioventricular nodal reentrant tachycardia ablation.

INTRODUCTION: Ablation for atrioventricular nodal reentrant tachycardia (AVNRT) classically utilizes evaluation of signal morphology within the anatomic region of the slow pathway (SP), which involves subjectivity. Ripple mapping (RM; CARTO-3© Biosense Webster Inc) displays each electrogram at its three-dimensional coordinate as a bar changing in length according to its voltage-time relationship. This allows prolonged, low-amplitude signals to be displayed in their entirety, helping identify propagation in low-voltage areas. We set out to evaluate the ability of RM to locate the anatomic site of the SP and assess its use in guiding ablation for AVNRT. METHODS: Patients ≤18 years with AVNRT in the EP laboratory between 2017 and 2021 were evaluated. RM was performed to define region of SP conduction in patients from 2019 to 2021, whereas standard electro-anatomical mapping was used from 2017 to 2019. All ablations were performed using cryotherapy. Demographics, outcomes, and analysis of variance in number of test lesions until success was compared between groups. RESULTS: A total of 115 patients underwent AVRNT ablation during the study; 46 patients were in the RM group and 69 were in the control group. There were no demographic differences between groups. All procedures, in both groups, were acutely successful. In RM group, 89% of first successful lesions were within 4 mm of the predicted site. There was significantly reduced variability in number of test lesions until success in the RM group (p = .01). CONCLUSION: RM is a novel technique that can help identify SP location, allowing for successful ablation of AVNRT with decreased variability.

Screening Electrocardiograms Have Low Utility in Medical Clearance Before Pediatric Inpatient Psychiatric Admission.

OBJECTIVES: Children presenting to the emergency department (ED) requiring psychiatric admission often undergo screening electrocardiograms (ECG) as part of the medical clearance process. The diagnostic yield of screening ECGs for this purpose has not been reported. The purpose of this study was to determine the clinical utility of screening ECGs in children and adolescents requiring acute inpatient psychiatric admission. METHODS: A single-center retrospective study of patients aged 5 to 18 years who did not have documented indications for ECG and underwent screening ECG before psychiatric inpatient admission over a 2-year period was conducted. Abnormal ECGs were identified via chart review and were reinterpreted by a pediatric cardiologist to determine potential significance to psychiatric care. Impact on treatment and disposition was examined. RESULTS: From January 2018 through December 2019, 252 eligible pediatric patients had a screening ECG in the ED before psychiatric admission. Twenty-one (8.3%) of these ECGs were interpreted as abnormal, and 6 (2.4%) were determined to be potentially relevant to psychiatric care in the setting of specific medication use. The abnormal ECG interpretations resulted in additional workup and/or cardiology consultation for 7 (2.7%) patients but had no impact on psychiatric admission. CONCLUSIONS: In the absence of concerning individual or family history or cardiac symptoms, routine screening ECGs as part of medical clearance for psychiatric admission are not warranted given the low yield of meaningful findings. The decision to obtain an ECG should be made with careful consideration of medical history and in the presence of specific indications.

A paediatric cardiology handbook for the digital age.

INTRODUCTION: Paediatric cardiology fellows, tasked with studying a large and dynamic field, may benefit from a quick-access digital resource that reflects contemporary practice. The objective of this study was to evaluate the effectiveness of a paediatric cardiology handbook smartphone app in enhancing the accessibility of information such as guidelines and recommendations for paediatric cardiology fellows. MATERIALS AND METHODS: The Peds Cardiology Handbook app (iOS) was designed using XCode and Swift programming. A pre-app survey and download instructions were sent to the US paediatric cardiology fellows, followed by a post-app survey. Fellows were asked to rate the ease of rapid access to various types of information. Responses were compared pre- and post-app using McNemar's test and Wilcoxon signed-rank test. RESULTS: Two-hundred and thirty paediatric cardiology fellows were contacted; 23% (n = 53) completed both the pre- and post-app surveys and were included for analysis. After using the app, fellows found it easier to quickly access information in eight out of nine domains evaluated (p < 0.05). All fellows found the app easy to use (100%), most felt that the app was well-organised (98%), contained reliable information (92%), and was useful for finding quick answers to clinical questions (87%). DISCUSSION: The Peds Cardiology Handbook iPhone app is a useful, reliable tool that provides quick access to high-yield information, including guidelines and references. Overall, paediatric cardiology fellows found it easier to rapidly access clinically relevant information after using the app. Future studies may be necessary to evaluate long-term use and impact on evidence-based practice.

Sotalol versus amiodarone for postoperative junctional tachycardia after congenital heart surgery.

BACKGROUND: Junctional ectopic tachycardia (JET) is a common arrhythmia after congenital heart disease surgery. There is variability in the choice of antiarrhythmic therapy, with amiodarone used commonly. Intravenous (IV) sotalol is a newly available agent that may be useful for JET. OBJECTIVE: The purpose of this study was to evaluate the safety and efficacy of IV sotalol for postoperative JET and compare outcomes with IV amiodarone. METHODS: This is a retrospective single-center study of all patients who received IV sotalol or IV amiodarone for postoperative JET at Texas Children's Hospital from December 15, 2015, to December 15, 2020. Data included antiarrhythmic efficacy, hemodynamics, and adverse effects. Successful JET control was defined as a decrease in JET rate to <170 beats/min (or decrease by >20%), or conversion to sinus rhythm, with persistent control over 24 hours without requiring alternative antiarrhythmics or mechanical support. RESULTS: A total of 32 patients (median age 71 days; interquartile range 17-221 days) received IV amiodarone (n = 20 [62%]) or IV sotalol (n = 12 [38%]) for postoperative JET. Amiodarone was successful in treating JET in 75% of cases; sotalol was successful in 83%. The JET rate decreased faster over the first 90 minutes after a sotalol bolus (25 beats/min per hour) than after an amiodarone bolus (8 beats/min per hour) (P < .01); no heart rate difference was seen after 24 hours. Amiodarone infusion was discontinued early because of hypotension/bradycardia in 2 patients; this was not required in any patients receiving sotalol. CONCLUSION: For children with postoperative JET, both IV sotalol and amiodarone are safe and efficacious. IV sotalol may lead to a faster improvement in heart rate.

Early Thromboprophylaxis Initiation is Associated With Reduced Fontan Thromboses in the Early Postoperative Period.

Fontan circuit thrombosis is a significant cause of early postoperative morbidity and mortality. Thrombosis incidence and relationship to thromboprophylaxis choice and timing of initiation are not well established. We sought to evaluate the incidence of Fontan circuit thrombosis in the first 30 postoperative days and its relationship to thromboprophylaxis choice and timing. Patients undergoing Fontan surgery, 2006-2016, were reviewed. Fontan circuit thrombosis was defined by sonographic detection of intracardiac or deep venous thrombi. Logistic regression was used to assess relationships between thromboprophylaxis characteristics and thrombosis. One hundred ninety-two patients underwent Fontan. Fontan thrombosis occurred in 19 (10%) patients. 54% were started on aspirin, 27% coumadin, 4% heparin, and 7% none. There was no relationship between thrombosis and baseline anatomy, Fontan type or fenestration. Median time to thromboprophylaxis initiation was 4 days (interquartile range 2-6). Patients not started on thromboprophylaxis had 44.8 times the odds of thrombosis as those on thromboprophylaxis (confidence interval 6.4-311.7, P < 0.01); no children starting thromboprophylaxis before postoperative day 2 developed thromboses. For every day that thromboprophylaxis was delayed, odds of thrombosis increased by 30% (odds ratio 1.3; CI 1.1-1.6, P < 0.01). There was no difference in the odds of thrombosis between children taking aspirin vs other thromboprophylaxis types. Odds of early postoperative Fontan circuit thrombosis are increased in patients in whom thromboprophylaxis is delayed beyond the second postoperative day, with no difference in the odds of thrombosis between patients initiated on aspirin vs other thromboprophylaxis. Early aspirin institution post Fontan is recommended to reduce morbidity. Ultra-mini-Abstract: Odds of early postoperative Fontan circuit thrombosis are increased in patients in whom thromboprophylaxis is delayed beyond the second postoperative day, with no difference in the odds of thrombosis between patients initiated on aspirin vs other thromboprophylaxis. Early aspirin institution post Fontan is recommended to reduce morbidity and resource utilization.

Speckle Tracking Echocardiography in Pediatric Patients with Premature Ventricular Contractions.

Premature ventricular contractions (PVCs) in pediatric patients without structural heart disease and normal left ventricular systolic function rarely require therapy, though it is unknown whether these patients have subclinical cardiac dysfunction. Speckle tracking echocardiography is an additional means of evaluating cardiac function in asymptomatic pediatric PVC patients with normal standard measures of left ventricular (LV) function. Asymptomatic pediatric patients (< 21 years) without congenital heart disease, LV ejection fraction (LVEF) ≥ 55% and PVC burden ≥ 5% on 24-h Holter monitor were included. Demographic information, exercise stress test results, standard echocardiographic measures of LV systolic function and PVC morphology by 12-lead ECG were collected. Peak global systolic longitudinal strain (GLS) from apical four-chamber view was analyzed offline. 29 patients were identified (mean age 11.7 ± 5.8 years, 49.2 ± 25.3 kg, 59% male). Mean PVC burden was 12.0 ± 7.0% (range 5-37.5%). 14/29 (48%) had exercise stress testing with evidence of PVCs; 9/14 (64%) had PVC suppression at a mean heart rate (HR) of 160 ± 23 bpm and 5/14 (36%) did not suppress at a mean maximum HR of 188 ± 9 bpm. All patients had normal strain values by speckle tracking echocardiography (mean LV GLS - 22.5 ± 2.0%, LV global circumferential strain - 25.3 ± 3.9 and RV GLS - 24.1 ± 3.0%). There was no correlation between PVC burden and cardiac function parameters. Asymptomatic pediatric patients without structural heart disease, preserved LVEF/shortening fraction and PVC burden ≥ 5% demonstrated normal cardiac function including strain patterns indicating no evidence of subclinical cardiac dysfunction. Larger scale studies and longitudinal evaluation of left ventricular function using speckle tracking echocardiography is warranted in this population.

Identification of Risk Factors for Early Fontan Failure.

Despite improvements in operative and perioperative care, the risk of significant morbidity and mortality for children undergoing Fontan procedures persists. Previous investigations have identified peri-Fontan characteristics that may predict early adverse events. The purpose of this study was to identify characteristics from throughout a patient's lifespan, including all perioperative stages, that might predict early Fontan failure-defined as death, Fontan takedown, or listing for cardiac transplantation before hospital discharge or within 30 postoperative days. A single-center retrospective study of all patients undergoing a Fontan procedure was performed. Patient and intervention-related characteristics were examined from birth through Fontan. Data were described using standard summary statistics. Univariable, logistic regression was used to examine associations with early Fontan failure. In total, 191 patients met inclusion criteria. The incidence of early Fontan failure was 4% (n = 8: 6 deaths, 2 Fontan takedowns). Neonatal balloon atrial septostomy was the only patient characteristic significantly associated with Fontan failure. Patients who underwent balloon septostomy had 8.5 times higher odds of Fontan failure (confidence interval (CI) 2.6-28.1, P < 0.001) than those who did not. Children who require balloon septostomy as neonates remain at higher risk of Fontan takedown, listing for heart transplantation, or death in the early post-Fontan period.

"If at first you don't succeed": repeat ablations in young patients with supraventricular tachycardia.

PURPOSE: Success rates for catheter ablation of supraventricular tachycardia (SVT) in the young exceed 90%. While studies have described reasons for initial ablation failure, less is known about outcomes of repeat ablation attempts. The purpose of this study was to report acute and mid-term success rates for second ablation attempts in young patients, as well as to analyze factors that may affect these outcomes. METHODS: Retrospective single-center study of all patients undergoing a second ablation attempt for WPW (Wolff-Parkinson-White) or SVT from 2008 to 2017. Inclusion criteria are all patients < 21 years old at the time of their first ablation who underwent a second ablation attempt. An intention to treat analysis was performed. RESULTS: Fifty-five patients met inclusion criteria, with a median age of 15 years (IQR 12-16). The most common arrhythmia mechanisms at repeat procedure were single accessory pathways (n = 32, 58%) and AVNRT (n = 14, 25%). Six patients (11%) were found to have a different SVT mechanism than at initial ablation. Acute success at repeat ablation was achieved in 48 patients (87%). At mid-term follow-up (10.5 months, IQR 0.6-25), four patients (8% of acute successes) experienced SVT recurrence. The overall success rate of repeat ablations, accounting for acute and mid-term failures, was 80%. CONCLUSIONS: In this report of 55 young patients who underwent repeat ablation for WPW and/or SVT, acute and mid-term success rates were 87% and 80%, respectively. These data may help inform decision-making when caring for patients with persistent or recurrent SVT after an initial ablation attempt.

Postpartum Depression in a General Pediatric Practice: Practical Methods for Improving Screening and Referrals.

Postpartum depression (PPD) is a common problem in new mothers. Untreated PPD is associated with behavioral and developmental problems in children. We examined the effects of an educational session about PPD and modification of the electronic medical record (EMR) on providers' screening for PPD. An education session was given to the physicians and pre and post surveys compared comfort and self-reported screening. Following the EMR change, a retrospective chart review was conducted from three time periods: group 1-before the conference, group 2-after the conference but before EMR change, and group 3-after screening in the EMR. Documented screening increased from 0% in group 1, to 2% in group 2, to 74% in group 3 (P < .001). Ten percent screened positive, but only 14% had documented referrals to a provider for treatment. The combination of provider education and screening questions integrated into the EMR enhanced PPD screening rates among physicians in a busy practice.