Anteroseptal Accessory Pathway Research Articles

PO-04-109 OUTCOMES OF RADIOFREQUENCY CATHETER ABLATION OF DISTINCT ANTERO-SEPTAL ACCESSORY PATHWAYS BY CONVENTIONAL ELECTROPHYSIOLOGICAL MAPPING

Ablation of para-hisian accessory pathways (APs) is challenging because of their proximity to the conduction system. A high incidence of atrio-ventricular (AV) conduction injury (up to 50%) was observed for the ablation of true para-hisian APs. In this retrospective study, we report the outcomes of a large series of patients with antero-septal APs (including true para-hisian APs) who underwent radiofrequency catheter ablation (RFCA). Among 1676 consecutive patients undergoing RFCA of APs between January 2016 and September 2022 in our center, 276 patients with an isolated antero-septal AP were enrolled. Conventional intracardiac mapping and fluoroscopy were used in all procedures. All procedures were performed by an experienced operator with a standard 3.5 mm irrigated tip catheter. A para-hisian AP was confirmed when an His potential was recorded by the distal ablation catheter at the site of earliest atrial activation during orthodromic AVRT or after ablation of the manifest AP. APs were categorized as true para-hisian if a sharp high-amplitude His potential was recorded. Among the 276 patients (mean age 27±10 years; 150 males) with an antero-septal AP: 55 patients (20%) had a true para-hisian AP (Group 1); 89 patients (32%) had a not-sharp low-amplitude His potential (Group 2); 132 patients (48%) had no His potential recorded (Group 3). The three Groups showed no significant difference in clinical (age, sex, history of AF and AVRT, structural heart disease) and EPS variables (conduction properties of APs and inducibility of AVRT and AF). Inferior vena cava (n=260) and aortic retrograde (n=16, targeting the left basal septum) approaches were used. Procedural acute success (no evidence of residual preexcitation or abnormal retrograde conduction) was obtained in all patients. No patient experienced acute severe complications. RF ablation time was longer in Group 1 (135±41 sec vs 115±27 sec [Group 2] vs 92 sec ±18 sec [Group 3], p=0.03). Accelerated junctional rhythm during RFCA was more frequent in Group 1 (25% vs 14% [Group 2] vs 3% [Group 3], p=0.02). After a median follow-up of 40 (2-78) months no high-grade AV block was reported. 1 patient of Group 1 had a recurrent para-hisian AP and underwent a second successful RFCA. In this large series of antero-septal APs (including a high number of true para-hisian APs), electrophysiologically-guided RFCA was safe and highly effective.

PO-03-125 VENTRICULAR PREEXCITATION AND PEDIATRIC HYPERTROPHIC CARDIOMYOPATHY: ETIOLOGY AND ACCESSORY PATHWAY CHARACTERISTICS

The etiology of pediatric hypertrophic cardiomyopathy (HCM) is varied. Ventricular preexcitation (VPe) is well recognized, yet little is known regarding the specific etiology, and accessory pathways (AP) characteristics. Define the etiology of HCM in patients with VPe and the characteristics of the responsible APs. Retrospective cohort study of patients <21 years of age with HCM/VPe from 2000-22. The etiology was defined as sarcomeric/non-sarcomeric (isolated HCM), storage disorder, metabolic disease, or genetic syndrome. AP were designated as atrioventricular (AV) or fasciculoventricular fibers (FVF) using standard invasive EP study criteria when available. AV APs were defined as high risk if any of the following were <250 ms: shortest preexcited RR interval in AF, shortest paced preexcited cycle length, or APERP. ECG characteristics were compared in patients with VPe exclusively secondary to an FVF to those with anteroseptal AP-mediated VPe. From a total of 345 patients with HCM, 28 (8%) had VPe and proportion with VPe varied significantly between etiologic groups: isolated HCM 10/220 (5%), storage 8/17 (47%), metabolic 5/19 (26%), genetic syndrome 5/89 (6%), p < 0.001. Six (21%) had clinical AF (1 with SPPRI <250 ms, 4 with storage disease). Invasive EP study was performed in 22, identifying 39 APs (23 AV AP, 16 FVF; fig 1). VPe resulted exclusively from an FVF in 8 (36%) patients. Multiple AV APs were seen in 8 (36%) and AV AP plus FVF in 10 (45%). Five (23%) patients had AV APs with high-risk conduction properties (≥1 in each etiologic group). Ablation was acutely successful in 13/14 patients with recurrence in 3. The only complication was a single case of heart block after ablation of a high-risk midseptal AP. Patients with storage disease had larger QRS amplitudes (median 42.3 v. 23.0 mm, p < 0.01). The delta wave amplitude did not discriminate between anteroseptal AP and FVF (median 4.3 v. 4.1 mm, p = 0.92). VPe and high risk or multiple AP may be associated with any etiology of childhood HCM. This is most common in storage disorders associated with high QRS amplitudes and clinical AF, with important implications for prognosis and management.

A challenging catheter ablation of anteroseptal manifest accessory pathway from non-coronary aortic cusp in a paediatric patient.

Twelve-lead ECG of a child with Wolff-Parkinson-White syndrome and systolic dysfunction was consistent with the anteroseptal accessory pathway. The earliest atrial activation during electrophysiological study was found between the right anteroseptal region near the HIS. Multiple femoral tract right-sided cryotest lesions followed by radiofrequency catheter irrigated through the jugular vein route were unsuccessful. Then, non-coronary aortic cusp mapping and cryoablation were successfully performed with a retroartic approach.

Examination and treatment of a female patient with symptomatic manifesting WPW phenomenon: case report

We describe a clinical case of 37 y.o. woman with anteroseptal accessory pathway associated with left ventricular dyssynchrony and ejection fraction reduction. Wolff-Parkinson-White syndrome and phenomenon diagnostic criteria are discussed.

Abstract 14513: An Aberrant Friend - Using Bundle Branch Block for Septal Accessory Pathway Localization

Introduction: While changes in the ventriculoatrial (VA) time with RBBB or LBBB during ORT utilizing a free wall accessory pathway (AP) is well described, such a change in VA time can also be helpful in identifying the location of a septal AP. Objectives: To demonstrate the effect of RBBB and LBBB aberrancy on the VA time for ORT involving septal AP and thereby assist in identifying a posteroseptal AP. Results: A 51-year-old man with WPW syndrome was referred for EP study and ablation due to palpitations. With programmed atrial extrastimulation, an atypical echo beat was noted. While attempting to induce tachycardia, double atrial extrastimuli resulted in non-sustained ORT both with RBBB and LBBB aberrancies (Figure). Measurement of the VA time during non-sustained ORT demonstrated a VA time that was longer in the presence of LBBB aberrancy (110ms) than RBBB aberrancy (97ms) compared to narrow QRS (95ms). Electroanatomic mapping identified the earliest atrial activation of the echo beat on the right posteroseptum. Radiofrequency ablation at this site resulted in immediate loss of ventricular pre-excitation. Conclusions: Changes in the VA interval during AP-mediated SVT are especially important for pathway localization. As demonstrated in prior studies, for free wall APs, the difference between sinus and bundle branch block time (ΔVA) is usually &gt;35ms compared to &lt;35ms for septal APs. Furthermore, studies described that for septal APs, posteroseptal APs have a greater VA time with LBBB, anteroseptal APs with RBBB and no significant change in VA time with midseptal APs. By demonstrating both RBBB and LBBB aberrancy in this patient, this case uniquely validates the concept that the VA time with LBBB aberrancy is greater with posteroseptal APs.

PC-577-04 ANTEROSEPTAL ACCESSORY PATHWAY: KILLING ONE BIRD WITH TWO STONES

21 year old healthcare worker with frequent palpitations leading to frequent hospitalizations with elevated heart rates up to 210 bpm noted on her watch with pre-excitation on ECG consistent with anteroseptal accessory pathway (AS AP). Describe a case of achieving antegrade conduction block in the AS AP with retrograde ablation approach and achieving retrograde conduction block with antegrade ablation approach. N/A Electrophysiological maneuvers were performed including parahisian pacing, apical/basal pacing confirming an AS AP with antegrade and retrograde conduction. Orthodromic reentrant tachycardia (ORT) was easily inducible with burst A pacing. Due to close proximity of the earliest site to the HIS using antegrade approach, decision was made to use the retrograde approach which showed an early site without HIS signal in the non coronary cusp (NCC). Ablation in the NCC resulted in antegrade conduction block after 1.4 seconds and was no longer seen until the end of the case (Fig A&B). Repeating the prior maneuvers showed persistent retrograde conduction and patient was still easily inducible for ORT. Additional ablation in the NCC did not terminate retrograde conduction. Antegrade approach was used for further ablation opposite the NCC at the earliest retrograde A during ORT which resulted in termination of ORT after 0.5 seconds (Figure D). Repeat maneuvers showed no evidence of pathway conduction and the patient was non inducible for ORT. No events at six month follow up. AS AP with successful ablation of antegrade conduction from a retrograde approach and successful ablation of retrograde conduction from an antegrade approach.

PO-672-01 RIGHT SIDED ANTEROSEPTAL ACCESSORY PATHWAY INDUCED CARDIOMYOPATHY

We describe 2 patients with right anteroseptal accessory pathway (ASAP) who developed new left ventricular systolic dysfunction (LVSD) due to worsening AV node conduction which resulted in more pre-excitation and frequent orthodromic reciprocating tachycardia (ORT).

786 A case of end-stage mitochondrial cardiomyopathy undergoing heart and kidney transplantation

Abstract Male, 46 year old. Family history: brother affected by deafness and repeated episodes of stroke at a young age. Pathological history: history of competitive sporting activity in which he underwent periodic outpatient checks and reported sporadic myalgic episodes. The patient was suffering from bilateral keratoconus. For the purpose of discovering Wolf–Parkinson–White syndrome with the presence of a right antero-septal accessory pathway, he underwent an electrophysiological study (2003) negative for inducible arrhythmias. During a routine checkup, a renal biopsy was performed to search for elevated blood creatinine, which concluded with acute interstitial nephritis (2005), treated ineffectively with steroids and resulted in dialysis-dependent stage V renal failure (2020). Following light tiredness, he underwent an echocardiographic examination (2009) which revealed the presence of dilated heart disease with reduced left ventricular systolic function. He underwent a cardiac MRI which showed diffuse spots of subepicardial late enhancement as a possible post-myocarditis outcome. At subsequent clinical-echocardiographic checks, progressive biventricular dysfunction, and signs of congestive heart failure were highlighted, for which medical therapy was progressively increased and insertion of an implantable cardioverter defibrillator in primary prevention for sudden cardiac death. At the subsequent clinical re-evaluations, there was evidence of progressive bilateral hearing loss. In consideration of the clinical picture and family history, considering the syndromic nature of the polypathologies to be likely, genetic investigation was required for mitochondrial diseases. Mutations 3242 and 3271mt-RNA and 13513 mtND5, frequent in the MELAS Syndrome, were searched in peripheral venous samples and resulted as negative. In 2020 he underwent an orthotopic heart transplant sec. Shamway followed by a kidney transplant from a compatible donor. In order to perform further diagnostic investigations, the explanted heart was sent to the Pathological Anatomy laboratory of the Umberto I Hospital: macroscopic analysis showed foci of fat replacement at the level of the anterior and posterior wall of the right ventricle (Figure); under microscopy, marked myocardial hypertrophy was observed, associated with cytoplasmic vacuolization of the cardiomyocytes, fibro-adipose substitution of the right ventricle, and replacement fibrosis in minute foci in the left ventricular level. A widespread and marked reduction in the enzymatic activity of cytochrome oxidase in cardiomyocytes and mitochondrial proliferation was demonstrated using histo-enzymatic staining, by staining for succinate dehydrogenase, concluding with mitochondrial disease. Mitochondrial diseases represent a challenge not only from the prognostic–therapeutic point of view but, remarkably, also from a diagnostic one: the patient received a correct diagnosis of the pathology that afflicted him, with almost two decades of delay. The integrated and multidisciplinary approach is desirable in order to obtain an early diagnosis.

P1011Electrophysiological trends in Wolff-Parkinson-White patients: a 33 years follow-up study

Abstract Background The Wolff-Parkinson-White (WPW) syndrome can be associated with sudden cardiac death, therefore risk assessment (RA) with electrophysiological (EP) testing (EPT) is mandatory to identify patients (pts) requiring catheter ablation (CAb). Our retrospective cohort study aimed to evaluate the variability of EP parameters during follow-up of WPW pts and the reliability of trans-esophageal EPT (TEEPT) for RA, evaluation of treatment efficacy, and EP follow-up of untreated athletes/pts. Method Data of 335 WPW pts, studied with TEEPT between 1985 and 2018, were retrospectively analyzed. Anterograde effective refractory period (ERP) of accessory pathways (AP) and of the atrioventricular node, Wenckebach point, shortest preexcited RR intervals (SPERRI) during atrial fibrillation (AF) and/or atrial pacing (At-P) and inducibility of supraventricular arrhythmias were assessed, at rest (supine and standing) and during effort. An AP was defined at high arrhythmogenic risk (HAR) if the anterograde AP-ERP and/or SPERRI (in AF or At-P) were ≤240 ms at rest or ≤200 ms during effort test. All patients were followed-up as outpatients or telephonically, as clinically required. 195 pts (17% female) were included, having exhaustive clinical information, two or more TEEPT and exhaustive clinical follow-up until late 2018. Time-evolution of EP parameters was evaluated, using parametric and non-parametric tests, as appropriate. Results and discussion Median age at first TEEPT was 20 years (IQR 16–29 years). Median follow- up was 44.3 months (IQR 16.4–122.9 months). Two pts (both identified at HAR and scheduled for surgery when ablation was unavailable) died suddenly, at rest. No other serious arrhythmic complication occurred, during the FU. Out of 19 pts (9.7% - Group A) showing enhanced AP conductivity at follow-up (mean ERP/SPERRI shortening: 30.8 ms, range 10–80 ms), 4 pts were found at HAR and underwent CAb. 176 pts (90.3% – Group B) showed a stable or impaired (25% under pharmacological treatment) AP conductivity during the follow-up. Their mean ERP/SPERRI increase was 39.7 ms (range 0–130 ms). Group A pts were significantly younger (20 vs 28 years old; 88% of Group A pts were &lt;30 years old) and more frequently male (94.1% vs 80.6%). A non-significant trend toward Group A was found for antero-septal APs (35% Group A vs 15.4% Group B). Conclusions TEEPT is a safe, non-invasive tool to stratify arrhythmogenic risk of WPW pts. Our data suggest that a watchful waiting is safe for low to moderate risk pts. Younger males with an antero-septal Kent bundle may deserve a more intensive EP follow-up. Aggressive therapy should be considered as mandatory only for symptomatic HAR pts, taking into account complications, risk/benefit ratio and pts' preferences. In other cases, medical therapy and watchful observation could be applied safely under periodical TEEPT, as appropriate.

Acute Outcomes for Cryoablation in Pediatric Patients with Perinodal Tachyarrhythmia: Single Center Report.

Cryoablation is an alternative treatment for atrioventricular nodal reentrant tachycardia (AVNRT) and right anteroseptal and midseptal accessory pathways (APs) with a low complication rate. A high recurrence rate is still a concern in pediatric patients. From February 2015 to March 2017, all consecutive patients who underwent cryoablation for supraventricular tachycardia were included in this study. The demographic and clinical data of the patients were reviewed. Fifty-two patients (AVNRT 43, anteroseptal and midseptal AP 9) were enrolled, including 24 males and 28 females. The median age at the time of the procedure was 15.6 years. For patients with AVNRT, 34 (79.1%) had the typical form, 5 had the atypical form (11.6%), and another 4 had both forms. For AP, four patients had right midseptal and 5 had right anteroseptal APs. The median total procedure time was 114 min (range 69-331 min), and the median fluoroscopy time was 25.9 min (range 9.2-99.6 min). After a median 6 attempts of cryomapping and 3 of cryoablation, the arrhythmia substrate was successfully ablated in 51 of 52 patients (98.1%). Ten developed transient second degree atrioventricular (AV) block and one developed transient third degree AV block, but none had permanent AV block or other complications. After a mean follow-up of 1.95 ± 0.54 years (range 1.1-2.86 years), there were three cases of recurrence (5.9%). The mean number of cryoablations decreased from 6.6 ± 6.4 (early group) to 3.1 ± 2.6 (late group) (p = 0.01) after a 1-year learning period. Cryoablation for AVNRT and anteroseptal and midseptal APs in pediatric and adolescent patients is safe and effective.

Differentiation of fasciculoventricular fibers from anteroseptal accessory pathways using the surface electrocardiogram

Fasciculoventricular fibers (FVFs) are responsible for 1%-5% of cases of asymptomatic preexcitation on the surface electrocardiogram (ECG). Unlike ventricular preexcitation seen in Wolff-Parkinson-White (WPW) syndrome, FVFs are not associated with sudden cardiac death from preexcited atrial fibrillation. The purpose of this study was to identify surface ECG variables that differentiate FVFs from true WPW syndrome. This is a retrospective case-control study comparing surface ECG characteristics of patients diagnosed with FVFs (cases) with those of patients with WPW syndrome and anteroseptal accessory pathways (controls) via intracardiac electrophysiology testing at a single institution from 2005 to2017. Twenty-four cases of FVFs confirmed by intracardiac electrophysiology testing were identified and compared with 48 consecutive controls with WPW syndrome and anteroseptal accessory pathways. Patients with WPW syndrome were found to have significantly higher delta wave amplitudes (4.8 ± 2.0 mm vs 1.9 ± 1.3 mm; P < .001), shorter PR intervals (94.6 ± 12.5 ms vs 106.8 ± 13.2 ms; P < .001), and longer QRS intervals (133.6 ± 19.0 ms vs 118.7 ± 24.7 ms; P = .006) than did those with FVFs. Multivariable logistic regression analysis identified the delta wave amplitude as the only independent predictor of WPW syndrome (odds ratio 3.1 per 1-mm increase; bootstrapped 95% confidence interval 1.5-6.4; c statistic 0.90; P = .002). The etiology of preexcitation in patients with an anteroseptal preexcitation pattern, whether because of a benign FVF or because of potentially serious WPW syndrome, can be noninvasively deduced using the surface ECG. A higher delta wave amplitude is an independent risk factor for the presence of WPW syndrome and can accurately distinguish WPW syndrome from a FVF with good test accuracy characteristics.

Cryoablation of the right anteroseptal or midseptal accessory pathways in children: A 2-year single-center experience.

Radiofrequency catheter ablation (RFCA) in the septum close to the atrioventricular node or His bundle has an increased risk of irreversible complications. Cryothermal energy has the advantages of reversible cryomapping and increased catheter stability. The study aims to evaluate the efficacy and safety of cryoablation of the right anteroseptal or midseptal accessory pathways (APs) in pediatric patients. A retrospective review was performed with 26 pediatric patients (16 males and 10 females; median age 6.0 years and average body weight 24.9kg) with paroxysmal supraventricular tachycardia (PSVT) in our Pediatric Heart Center from 2014 to 2016. Half of them had manifest APs. All the children underwent cryoablation for the treatment of PSVT because of the right anteroseptal or midseptal APs (16 cases had right anteroseptal APs and 10 cases had right midseptal APs). Acute cryoablation success was achieved in 23 cases (88%, 23/26). Atrioventricular block (AVB) occurred in eight cases (31%, 8/26) during the procedures and normal atrioventricular conduction recovered in seven cases except a case with I°AVB. During follow-up, three cases recurred (13%, 3/23) and no permanent high degree AVB was found. Cryoablation of the right anteroseptal or midseptal APs in pediatric patients is both safe and effective.

Comparison of the Accuracy of Three Algorithms in Predicting Accessory Pathways among Adult Wolff-Parkinson-White (WPW) Syndrome Patients in our Population

Background: after the introduction of catheter ablation of atrioventricular accessory pathways (APs) in Wolff-Parkinson-White (WPW) syndrome, to facilitate planned ablation and minimize catheter-related injury, predicting the AP was required. Localization of APs can be anywhere around the atrioventricular (AV) annuli, left- or right-sided, or within the septum or a rare possibility of Mahaim fibers. Objective: to compare between three algorithms in their accuracy in predicting the exact site of accessory pathway. Patients and Methods: one hundred patients with manifest pre-excitation who underwent electrophysiological study (EPS) and successful ablation of accessory pathway who were subjected to history taking, complete physical examination stressing on 12-lead of pre-excited electrocardiogram (ECG). Results: the distributions of the accessory pathway with left lateral accessory pathway being the most prevalent (27%) while the postero-lateral being the least prevalent one (2%) and that Right-sided accessory pathway was most frequently predicted by Arruda algorithm in 31% of patients and least frequently predicted by D’Avila in 17% of patients while its actually present in 23% of patients according to the EP study, Left-sided accessory pathway was most frequently predicted by D’Avila (61%) and least frequently predicted by Arruda (49%) whereas it was truly present in 51% of patients according to EP study. Mid and antero-septal accessory pathways were most frequently predicted by Chiang and least frequently predicted by Arruda while it was present in 26% of cases proved by EP study. In all algorithms, 72 % of predictions were correct for Chiang, 81 % for D’Avila, and 71 % for Arruda and the percentage of predictive accuracy of all algorithms did not differ between the algorithms (p=1.000; p=0.076; p=0.064, respectively) The best algorithm for prediction of right-sided and left-sided accessory pathways was D’Avila (p<0.001). The best algorithm that is particularly useful in predicting antero-septal and mid-septal accessory pathways was Chiang (p<0.001). Conclusion: prior knowledge of the AP location allows better planning, faster and safer procedure, as well as decreased exposure to ionizing radiation and unnecessary punctures. In all algorithms, 72% of predictions were correct for Chiang, 81% for D'Avila, and 71% for Arruda and the percentage of predictive accuracy of all algorithms did not differ between the algorithms (p=1.000; p=0.076; p=0.064, respectively). The best algorithm for prediction of right-sided and left-sided accessory pathways was D'Avila (p<0.001). The best algorithm that is particularly useful in predicting anteroseptal and mid-septal accessory pathways was Chiang (p<0.001).

Comparison of the Accuracy of Three Algorithms in Predicting Accessory Pathways among Adult Wolff-Parkinson-White (WPW) Syndrome Patients in our Population

Background: after the introduction of catheter ablation of atrioventricular accessory pathways (APs) in Wolff-Parkinson-White (WPW) syndrome, to facilitate planned ablation and minimize catheter-related injury, predicting the AP was required. Localization of APs can be anywhere around the atrioventricular (AV) annuli, left- or right-sided, or within the septum or a rare possibility of Mahaim fibers. Objective: to compare between three algorithms in their accuracy in predicting the exact site of accessory pathway. Patients and Methods: one hundred patients with manifest pre-excitation who underwent electrophysiological study (EPS) and successful ablation of accessory pathway who were subjected to history taking, complete physical examination stressing on 12-lead of pre-excited electrocardiogram (ECG). Results: the distributions of the accessory pathway with left lateral accessory pathway being the most prevalent (27%) while the postero-lateral being the least prevalent one (2%) and that Right-sided accessory pathway was most frequently predicted by Arruda algorithm in 31% of patients and least frequently predicted by D’Avila in 17% of patients while its actually present in 23% of patients according to the EP study, Left-sided accessory pathway was most frequently predicted by D’Avila (61%) and least frequently predicted by Arruda (49%) whereas it was truly present in 51% of patients according to EP study. Mid and antero-septal accessory pathways were most frequently predicted by Chiang and least frequently predicted by Arruda while it was present in 26% of cases proved by EP study. In all algorithms, 72 % of predictions were correct for Chiang, 81 % for D’Avila, and 71 % for Arruda and the percentage of predictive accuracy of all algorithms did not differ between the algorithms (p=1.000; p=0.076; p=0.064, respectively) The best algorithm for prediction of right-sided and left-sided accessory pathways was D’Avila (p<0.001). The best algorithm that is particularly useful in predicting antero-septal and mid-septal accessory pathways was Chiang (p<0.001). Conclusion: prior knowledge of the AP location allows better planning, faster and safer procedure, as well as decreased exposure to ionizing radiation and unnecessary punctures. In all algorithms, 72% of predictions were correct for Chiang, 81% for D'Avila, and 71% for Arruda and the percentage of predictive accuracy of all algorithms did not differ between the algorithms (p=1.000; p=0.076; p=0.064, respectively). The best algorithm for prediction of right-sided and left-sided accessory pathways was D'Avila (p<0.001). The best algorithm that is particularly useful in predicting anteroseptal and mid-septal accessory pathways was Chiang (p<0.001).

Highlights From the Circulation Family of Journals

Highlights From the <i>Circulation</i> Family of Journals

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. A retrospective, descriptive study of aortic cusp ablation in five pediatric electrophysiology centers from 2008 to 2014 was performed. All patients <21 years of age who underwent ablation in the aortic cusps were included. Factors analyzed included patient demographics, procedural details, outcomes, and complications. Thirteen patients met inclusion criteria (median age 16 years [range 10-20.5] and median body surface area 1.58 m2 [range 1.12-2.33]). Substrates for ablation included: nine premature ventricular contractions or sustained ventricular tachycardia (69%), two concealed anteroseptal accessory pathways (APs) (15%), one Wolff-Parkinson-White with an anteroseptal AP (8%), and one ectopic atrial tachycardia (8%). Three-dimensional electroanatomic mapping in combination with fluoroscopy was used in 12/13 (92%) patients. Standard 4-mm-tip radiofrequency (RF) current was used in 11/13 (85%) and low-power irrigated-tip RF in 2/13 (15%). Angiography was used in 13/13 and intracardiac echocardiography was additionally utilized in 3/13 (23%). Ablation locations included: eight noncoronary (62%), three left (23%), and two right (15%) cusps. Ablation was acutely successful in all patients. At median follow-up of 20 months, there was one recurrence of PVCs (8%). There were no ablation-related complications and no valvular injuries observed. Arrhythmias originating from the coronary cusps in this series were successfully and safely ablated in young people without injury to the coronary arteries or the aortic valve.

Electrocardiographic Preexcitation and Risk of Cardiovascular Morbidity and Mortality: Results From the Copenhagen ECG Study.

The majority of available data on the clinical course of patients with ventricular preexcitation in the ECG originates from tertiary centers. We aimed to investigate long-term outcomes in individuals from a primary care population with electrocardiographic preexcitation. Digital ECGs from 328 638 primary care patients were collected during 2001 to 2011. We identified 310 individuals with preexcitation (age range, 8-85 years). Data on medication, comorbidity, and outcomes were collected from Danish nationwide registries. The median follow-up time was 7.4 years (quartiles, 4.6-10.3 years). Compared with the remainder of the population, patients with preexcitation had higher adjusted hazards of atrial fibrillation (hazard ratio [HR], 3.12; 95% confidence interval [CI], 2.07-4.70) and heart failure (HR, 2.11; 95% CI, 1.27-3.50). Subgroup analysis on accessory pathway location revealed a higher adjusted hazard of heart failure for a right anteroseptal accessory pathway (HR, 5.88; 95% CI, 2.63-13.1). There was no evidence of a higher hazard of death among individuals with preexcitation when looking across all age groups (HR, 1.07; 95% CI, 0.68-1.68). However, a statistically significant (P=0.01) interaction analysis (<65 versus ≥65 years) indicated a higher hazard of death for patients with preexcitation ≥65 years (HR, 1.85; 95% CI, 1.07-3.18). In this large ECG study, individuals with preexcitation had higher hazards of atrial fibrillation and heart failure. The higher hazard of heart failure seemed to be driven by a right anteroseptal accessory pathway. Among elderly people, we found a statistically significant association between preexcitation and a higher hazard of death.

A case of Type-C Wolff–Parkinson–White syndrome with severe left ventricular dysfunction: Efficacy of catheter ablation

The present case report describes a 59-year-old female with manifest Wolff–Parkinson–White syndrome and severe left ventricular (LV) dysfunction, however, there was no indication of heart palpitations. The polarity of delta is consistent with the features of the right anteroseptal accessory pathways (APs). The echocardiography showed a remarkable dyssynchrony of the LV wall motion. To circumvent the cardiac dysfunctions, radiofrequency catheter ablation (RFCA) was successfully performed to disconnect the AP. Thereafter, the dyssynchrony disappeared, and the clinical reports observed 6 months following RFCA showed that the LV ejection fraction had been improved from 13% up to 48%, in addition to the improvement in other parameters. The RFCA prevented her from receiving a cardiac resynchronization therapy defibrillator as well as a heart transplantation.<Learning Objective: There is a concern about the possibility that some patients with Wolff-Parkinson-White (WPW) syndrome and heart failure may be diagnosed with dilated cardiomyopathy (DCM). Because catheter ablation of the accessory pathway may improve the left ventricular (LV) dysfunction, one should exclude the accessory pathway conduction-induced LV dyssynchrony and LV dysfunction before diagnosing DCM. Even in absence of palpitations, catheter ablation may be effective in patients with manifest WPW syndrome to prevent the progression of LV dysfunction.>

Various routes and techniques for ablation of parahisian bypass tracts

I have read with great interest the article entitled ‘Successful catheter ablation of an anteroseptal accessory pathway without impairing the atrioventricular conduction’ by Nishiyama et al. in a recent issue of the journal [ [1] Nishiyama T. Kimura T. Nishiyama N. Aizawa Y. Fukuda K. Takatsuki S. Successful catheter ablation of an anteroseptal accessory pathway without impairing the atrioventricular conduction. Int. J. Cardiol. 2016; 222: 782-784 Abstract Full Text Full Text PDF PubMed Scopus (1) Google Scholar ]. The authors described a successful ablation of a parahisian bypass tract using radiofrequency energy.

Successful catheter ablation of an anteroseptal accessory pathway without impairing the atrioventricular conduction

Successful catheter ablation of an anteroseptal accessory pathway without impairing the atrioventricular conduction