Atrialized right ventricular chamber as a source of ventricular tachycardia in Ebstein's anomaly. Analysis of two successful catheter ablation cases.

Ventricular tachycardia in Ebstein's anomaly patients is rare and increases the risk of sudden death up to 6 times. We present two cases of Ebstein's anomaly, the first of them with a history of Glenn surgery and biological prosthesis at tricuspid position and the second case without surgical repair. Both admitted to the emergency room due to ventricular tachycardia poorly tolerated. Detailed substrate characterization and pace mapping showed fragmented signals in the area of atrialized right ventricle and correlated were pace mapping reproduced morphology identical to the clinical VT, ablation at this sites were successful without recurrence during follow-up.

Out-of-hospital cardiac arrest due to idiopathic ventricular fibrillation in patients with normal electrocardiograms: results from a multicentre long-term registry.

AIMS: To define the clinical characteristics and long-term clinical outcomes of a large cohort of patients with idiopathic ventricular fibrillation (IVF) and normal 12-lead electrocardiograms (ECGs). METHODS AND RESULTS: Patients with ventricular fibrillation as the presenting rhythm, normal baseline, and follow-up ECGs with no signs of cardiac channelopathy including early repolarization or atrioventricular conduction abnormalities, and without structural heart disease were included in a registry. A total of 245 patients (median age: 38 years; males 59%) were recruited from 25 centres. An implantable cardioverter-defibrillator (ICD) was implanted in 226 patients (92%), while 18 patients (8%) were treated with drug therapy only. Over a median follow-up of 63 months (interquartile range: 25-110 months), 12 patients died (5%); in four of them (1.6%) the lethal event was of cardiac origin. Patients treated with antiarrhythmic drugs only had a higher rate of cardiovascular death compared to patients who received an ICD (16% vs. 0.4%, P = 0.001). Fifty-two patients (21%) experienced an arrhythmic recurrence. Age ≤16 years at the time of the first ventricular arrhythmia was the only predictor of arrhythmic recurrence on multivariable analysis [hazard ratio (HR) 0.41, 95% confidence interval (CI) 0.18-0.92; P = 0.03]. CONCLUSION: Patients with IVF and persistently normal ECGs frequently have arrhythmic recurrences, but a good prognosis when treated with an ICD. Children are a category of IVF patients at higher risk of arrhythmic recurrences.

One-year follow-up after single procedure Cryoballoon ablation: a comparison between the first and second generation balloon.

BACKGROUND: With respect to the first generation Cryoballoon (CB), the second generation (Cryoballoon Advance [CB-A], Medtronic, Minneapolis, MN, USA) was designed with technical modifications resulting in a larger and more uniform zone of freezing on the balloon's surface aiming at procedural outcome improvement in the setting of atrial fibrillation (AF) ablation. However, a comparison between both technologies on a midterm follow-up is missing in today's literature. METHODS: A total of 100 patients (the last 50 patients with the first generation CB and the first 50 patients with the second generation CB-A upon its inception in our center) having undergone a single CB ablation for paroxysmal AF (PAF) and having completed a 12-month follow-up, were consecutively included in our study. Freedom from AF off-antiarrhythmic drugs (AADs) after a single procedure was 78% (39/50) in CB-A and 58% (29/50) in the CB group (P = 0.03) during the whole follow-up duration. Considering a blanking period of 3 months, freedom from AF off-AAD was achieved in 84% (42/50) in CB-A, while 66% (33/50) were free from recurrence in the CB group (P = 0.038). Right phrenic nerve palsy (PNP) occurred in 8 patients (16%) in CB-A group and in 4 patients (8%) in the CB group. CONCLUSION: Freedom from AF on 12 months follow-up was significantly higher in the CB-A group with respect to the first generation device. The most frequent complication observed was PNP.

One year incidence of iatrogenic atrial septal defect after cryoballoon ablation for atrial fibrillation.

INTRODUCTION: Pulmonary vein (PV) isolation by means of cryoballoon (CB) technology is an effective treatment for symptomatic paroxysmal atrial fibrillation (AF) refractory to antiarrhythmic drug therapy. The CB requires a 15F transseptal sheath that may lead to the creation of a iatrogenic atrial septal defect (IASD). METHODS AND RESULTS: Individuals having undergone PV isolation by the means of CB ablation and a subsequent transesophageal echocardiography (TEE) examination during postablation follow-up were consecutively included. Thirty-nine patients formed the study group (31 male, 76.9%; mean age 57.4 ± 13.7 years). IASD was present in 8 (20%) of them after a mean follow-up time of 11.7 months. Mean diameter of the defect was 0.57 cm × 0.48 cm; only left to right shunt was observed. No adverse events were recorded in these patients during the follow-up. CONCLUSION: IASD after CB ablation of AF is present in up to 20% of patients after 1 year. Although no adverse clinical events were recorded in patients with persistence of IASD, this complication should not be underestimated and systematic echocardiographic examinations might be advised at regular intervals in the follow-up period after CB. Further studies with larger population and follow-up might be required to confirm our findings.

Clinical characteristics, management, and prognosis of elderly patients with Brugada syndrome.

BACKGROUND: The clinical course and prognosis of Brugada syndrome (BS) in the elderly is unknown. The purpose of this study was to investigate the clinical characteristics, management, and prognosis of BS in an elderly population. METHODS AND RESULTS: A total of 437 patients with BS were included in this study. Patients were categorized in 2 groups according to the age at the time of diagnosis: <60 years (N = 363) and ≥60 years (N = 74). Moreover, an elderly patients' subgroup analysis was performed between patients with an age between 60 and 70 years (N = 49) and subjects older than 70 years (N = 25). Among elderly patients (50% male, mean age: 67 ± 6 years), family history of sudden death (SD) and induction of sustained ventricular arrhythmias during programmed ventricular stimulation were less frequent as compared to younger patients. Two patients (3%) had a previous episode of aborted SD. Elderly patients with BS presented more frequently with ECG conduction disturbances or previous transient advanced atrioventricular block as compared to younger patients. Of the elderly patients, 42% underwent implantable cardioverter defibrillator implantation and 7% received a pacemaker. After a mean follow-up time of 54 ± 18 months, none of the elderly patients with BS older than 70 years experienced documented life-threating ventricular arrhythmias. Family screening was performed in 58 family members and a BS diagnosis was confirmed in 49%. CONCLUSION: The clinical features and the benign prognosis of BS patients older than 70 years likely identify a lower risk category of patients as compared to younger individuals. The device-guided management in this setting remains individualized and sometimes controversial. Moreover, BS diagnosis in the elderly should not be missed, mainly due to the clinical impact on the family of elderly patients.

Comparison of the patient-activated event recording system vs. traditional 24 h Holter electrocardiography in individuals with paroxysmal palpitations or dizziness.

AIMS: Electrocardiographic documentation of symptomatic episodes of palpitations by means of traditional methods such as 24 h Holter monitoring (HM) or loop recorders is challenging. Patient-activated electrocardiography (ECG) recorders have been proved to be a useful tool in the diagnosis of arrhythmias in these patients. However, no comparison studies between the two techniques have been conducted. The aim of this study was to compare the diagnostic value of Holter ECG and a patient-activated event recorder (OMRON portable HeartScan ECG Monitor(®)) (HeartScan) in the detection of arrhythmias in patients with paroxysmal palpitations or dizziness suggestive of cardiac arrhythmias. METHODS AND RESULTS: Patients with paroxysmal palpitations or dizziness were eligible for this study. All patients underwent an HM for 24 h and a 15-day HeartScan after the HM. Six hundred and twenty-five patients (48% male, mean age: 37 ± 11 years) were included in the study. All patients present with normal heart structure, normal baseline 12-lead ECG, and normal echocardiogram. Indications for ECG monitoring were palpitations in 577 patients (92.3%) and dizziness in 48 (7.7%). Holter monitoring offered a clinical diagnosis in 11 patients (1.8%). Conversely, HeartScan diagnosed the clinical arrhythmia in 558 individuals (89%). Detection of symptoms-related arrhythmias by means of HeartScan was significantly higher when compared with HM (P < 0.01). CONCLUSION: The studied system proved to be an efficient event recorder providing the diagnosis of the clinical arrhythmia in 89% of patients with paroxysmal palpitations or dizziness. Further studies are needed to confirm our results.

Pulmonary vein isolation in patients with Brugada syndrome and atrial fibrillation: a 2-year follow-up.

AIMS: Pharmacological treatment of atrial fibrillation (AF) in the setting of Brugada syndrome (BS) might be challenging as many antiarrhythmic drugs (AADs) with sodium channel blocking properties might expose the patients to the development of ventricular arrhythmias. Moreover, patients with BS and implantable cardioverter-defibrillator (ICD) might experience inappropriate shocks because of AF with rapid ventricular response. The role of pulmonary vein isolation (PVI) in patients with BS and recurrent episodes of AF has not been established yet. In this study, we analysed the outcome of PVI using radiofrequency energy or cryoballoon (CB) ablation at 2 years follow-up. METHODS AND RESULTS: Consecutive patients with BS having undergone PVI for drug-resistant paroxysmal AF were eligible for this study. Nine patients (three males; mean age: 52 ± 26 years) were included. Six patients (67%) had an ICD implanted of whom three had inappropriate shocks because of rapid AF. At a mean 22.1 ± 6.4 months follow-up, six patients (67%) were free of AF without AADs. None of the three patients who had experienced inappropriate ICD interventions for AF had further ICD shocks after ablation. CONCLUSION: In our study PVI can be an effective and safe procedure to treat patients with BS and recurrent episodes of paroxysmal AF.

Prevalence and electrocardiographic characteristics of early repolarization pattern in young teen athletes.

INTRODUCTION: Early repolarization (ERP) is a common electrocardiographic finding. Its potential to cause cardiac arrhythmias has been hypothesized from experimental studies, but it is not known whether there is a clinical association with sudden cardiac arrest. METHODS: 122 subjects (100% males; mean age: 13.5 +/- 2.7 years) were included from a local youth soccer team in Belgium. All subjects underwent physical examination and a 12-lead ECG was taken. The main objective of the study was to evaluate early repolarization patterns and to determine its prevalence. RESULTS: Of the 122 included subjects, 1 subject with Coumel tachycardia was excluded.The overall prevalence of ERP in our study population was 36%, with 9.1% in the inferior leads, 8.2% in the lateral leads and 18.2% both leads. A family history of sudden cardiac death (SCD) was not higher in the group of ERP (N=3; 6.8%) compared to the non-ERP group (N = 4; 5.2%) (P = 0.713). Interestingly, incomplete right bundle-branch block (IRBBB) was significantly lower among all subjects with ERP (N = 15; 34.1%), compared to those without ERP (N = 49; 63%) (P < 0.002). CONCLUSION: ERP is a common finding in young teen athletes. In this population global ERP (both inferior and lateral) is more common than isolated inferior or lateral ERP. Young age might be a contributing factor in causing a more diffuse repolarization abnormality.

Repeat procedure using radiofrequency energy for recurrence of atrial fibrillation after initial cryoballoon ablation: a 2-year follow-up.

AIMS: The ideal energy source needed to perform 're-isolation' of the pulmonary veins (PVs) during a repeat procedure for recurrence of paroxysmal atrial fibrillation (AF) has not been established yet. In this study we analysed the outcome of repeat procedure using radiofrequency (RF) energy after initial cryoballoon (CB) ablation at 2-year follow-up. METHODS AND RESULTS: Consecutive patients having undergone PVs isolation as repeat procedure for recurrent AF after an initial CB ablation were eligible for this study. Twenty-nine patients (22 male 76%, mean age: 55 ± 17 years) were included. Mean time to repeat ablation was 12 ± 7 months. Recovered PV conduction could be documented in a mean 2.45 ± 0.7 veins in each patient. At mean 20.2 ± 10.7 months follow-up, a total of 16 patients (55%) were free of AF at without antiarrhythmic drugs (AADs). An adjunctive 31% was AF free with previously ineffective AADs. A major complication with no permanent clinical sequelae occurred only in one patient. CONCLUSION: Repeat RF ablation following CB in case of AF recurrence is effective and safe.

[Left bundle branch stimulation in diffuse electrical heart disease in a pediatric patient]. / Estimulación de rama izquierda en enfermedad eléctrica difusa cardiaca en una paciente pediátrica.

Left bundle branch stimulation is a second-line strategy in patients where His bundle stimulation is not optimal. Currently, no cases of left bundle branch stimulation have been reported in patients with diffuse electrical cardiac disease or in the pediatric population.

Acute and long-term success of ventricular tachycardia ablation in patients with ischemic heart disease in a Mexican center.

Objective: . To report the results of ventricular tachycardia (VT) catheter ablation in ischemic heart disease (IHD), and to identify risk factors associated with recurrence in a Mexican center. Materials and methods: . We made a retrospective review of the cases of VT ablation performed in our center from 2015 to 2022. We analyzed the characteristics of the patients and those of the procedures separately and we determined factors associated with recurrence. Results: . Fifty procedures were performed in 38 patients (84% male; mean age 58.1 years). Acute success rate was 82%, with a 28% of recurrences. Female sex (OR 3.33, IC 95% 1.66-6.68, p=0.006), atrial fibrillation (OR 3.5, IC 95% 2.08-5.9, p=0.012), electrical storm (OR 2.4, IC 95% 1.06-5.41, p=0.045), functional class greater than II (OR 2.86, IC 95% 1.34-6.10, p=0.018) were risk factors for recurrence and the presence of clinical VT at the time of ablation (OR 0.29, IC 95% 0.12-0.70, p=0.004) and the use of more than 2 techniques for mapping (OR 0.64, IC 95% 0.48-0.86, p=0.013) were protective factors. Conclusions: . Ablation of ventricular tachycardia in ischemic heart disease has had good results in our center. The recurrence is similar to that reported by other authors and there are some factors associated with it.

Epicardial ablation of incessant left atrial appendage tachycardia in a case with tachycardiomyopathy.

Atrial tachycardias originated at the left atrial appendage (LAA) are uncommon; often they are incessant and might induce tachycardiomyopathy, as discussed by Hillock et al. (Heart Rhythm;3(4):467-469, 2006). A case of a 21-year-old woman with incessant atrial tachycardia is presented, refractory to medical therapy, echocardiography showed global dilation with LV ejection fraction of 20%. After two failed endocardial ablations, an epicardial access was attempted. The earliest activation site was located at the tip of the epicardial aspect of the LAA. RFCA was successful at this site. The patient remains asymptomatic during a follow-up of 10 months; the ventricular function was completely recovered after 6 months (LVEF of 50%).

Impact of the coronavirus disease-19 pandemic on electrophysiological procedures at a national referral center.

INTRODUCTION: The coronavirus disease (COVID-19) pandemic has generated serious repercussions on the health system, reducing the number of all cardiology procedures worldwide. OBJECTIVES: Describe the impact of the COVID-19 pandemic on the procedures performed by the electrophysiology department in a national referral center. METHODS: We made a retrospective review of our data base and we compared procedures made in the past 3 years since 2017-2019 with the procedures made in the 2020. We divided the procedures into two large groups: Cardiac Implantable Electronic Devices (CIED) related procedures and electrophysiological procedures (EP) which included conventional and complex ablations. RESULTS: There was a significant reduction in all the procedures, the average of procedures performed in the last 3 previous years was 467, while in 2020, we performed only 319 (p = 0.01); this represents a reduction of 33.4% in the total number of procedures. There was no statistical difference regarding the CIED related procedures, the average of procedures in the past 3 previous years was 174, and in 2020 we performed 190 procedures (p = 0.46). Regarding the EP, the average of the past 3 previous years was 293, while in 2020, we performed only 129 procedures (p < 0.01). The reduction in the EP was 55.97%. The most affected months were April, May, and June. CONCLUSIONS: The COVID-19 pandemic considerably affected the number of the procedures in our center, reducing it by 33.4%. The reduction of procedures fundamentally affected the ablations, with a reduction of 55.97%. The number of CIED related procedures was not affected.

Role of the burden of premature atrial contractions during the blanking period following second-generation cryoballoon ablation in predicting late recurrences of atrial arrhythmias.

PURPOSE: Recent data suggests that high burden of premature atrial complexes after pulmonary vein isolation predicts recurrences of atrial arrhythmias. The present study sought to assess the role of premature atrial complexes burden in predicting atrial arrhythmias recurrences in patients with atrial fibrillation (AF) who have undergone second-generation cryoballoon ablation (CB-Adv). METHODS: Consecutive patients with drug-resistant paroxysmal atrial fibrillation who underwent pulmonary vein isolation using CB-Adv technology as the index procedure were retrospectively included. Twenty-four-hour Holter recordings were performed for every patient. Based on previously published data, a burden of more than 76 premature atrial complexes per day was considered as being high. RESULTS: One hundred and seven patients were included in the analysis. The recurrence rate among the group of patients with more than 76 premature atrial complexes per day was significantly higher compared with the group with a lower burden of premature atrial complexes (47.5 vs 11.9%, respectively; p < 0.001). In the multivariate analysis, the documentation of more than 76 premature atrial complexes per day registered at 1 month and at the end of the blanking period, predicted late recurrence of atrial arrhythmias. CONCLUSIONS: Frequent premature atrial complexes in the early stages after CB-Adv ablation strongly predict late recurrences of atrial arrhythmias.

[Cryoablation: Clinical applications in cardiac electrophysiology from their biophysical bases]. / Crioablación: aplicaciones clínicas en la electrofisiología cardiaca a partir de sus bases biofísicas.

Cryoablation is an energy alternative to radiofrequency for ablation of various arrhythmias, where its unique biophysical properties offer a greater safety profile. Since its first use for the surgical treatment of different arrhythmias until its conceptualization in the current technical transcatheter, cryoablation has proven not to be only a safe source of energy, but also an effective source in the long-term. While the radiofrequency has been the energy most used for isolation of pulmonary veins in atrial fibrillation ablation, technological advances in cryoballon have managed to simplify the procedure without sacrificing its effectiveness. Cryoablation has been widely used for arrhythmias located in high-risk locations, such as the ablation of the atrioventricular nodal reentrant tachycardia and septal accessory pathways, due to its theoretical null risk of complete AV block. This review intends to give the clinical applications of the cryothermy through a thorough understanding of their biophysical basis.

Long-Term Trends in Newly Diagnosed Brugada Syndrome: Implications for Risk Stratification.

BACKGROUND: A proband of Brugada syndrome (BrS) is the first patient diagnosed in a family. There are no data regarding this specific, high-risk population. OBJECTIVES: This study sought to investigate the Brugada probands diagnosed from 1986 through the next 28 years. METHODS: We included 447 probands belonging to families with a diagnostic type 1 electrocardiogram Brugada pattern. The database was divided into 2 periods: the first period identified patients who were part of the initial cohort that became the consensus document on BrS in 2002 (early group); the second period reflected patients first diagnosed from 2003 to January 2014 (latter group). RESULTS: There were 165 probands in the early group and 282 in the latter group. Aborted sudden death as the first manifestation of the disease occurred in 12.1% of the early group versus 4.6% of the latter group (p = 0.005). Inducibility during programmed electrical stimulation was achieved in 34.4% and 19.2% of patients, respectively (p < 0.001). A spontaneous type 1 electrocardiogram pattern at diagnosis was present in 50.3% early versus 26.2% latter patients (p = 0.0002). Early group patients had a higher probability of a recurrent arrhythmia during follow-up (19%) than those of the latter group (5%) (p = 0.007). The clinical suspicion and use of a sodium-channel blocker to unmask BrS has allowed earlier diagnoses in many patients. CONCLUSIONS: Since being first described, the presentation of BrS has changed. There has been a decrease in aborted sudden cardiac death as the first manifestation of the disease among patients who were more recently diagnosed. These variations in initial presentation have important clinical consequences. In this setting, the value of inducibility to stratify individuals with BrS has changed.