Athletes and suspected catecholaminergic polymorphic ventricular tachycardia: Awareness and current knowledge.

INTRODUCTION: Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a cardiac inherited arrhythmogenic disease potentially leading to sudden cardiac death that is determined by electrical instability exacerbated by acute adrenergic tone. METHODS AND RESULTS: Despite its life-threatening nature, CPVT remains potentially unnoticed since diagnosis may be difficult especially in apparently healthy athletes. This review summarizes current knowledge and shortcomings of CPVT, focusing on genetics, arrhythmic mechanisms, sport preparticipation screening, and current recommendations. CONCLUSIONS: The paper captures the importance of CPVT athletes regarding the necessity of risk stratification, as well as the importance of maintaining a healthy lifestyle.

Subcutaneous versus transvenous implantable cardioverter-defibrillator among drug-induced type-1 ECG pattern Brugada syndrome: a propensity score matching analysis from IBRYD study.

No real-world data are available about the complications rate in drug-induced type 1 Brugada Syndrome (BrS) patients with an implantable cardioverter-defibrillator (ICD). Aim of our study is to compare the device-related complications, infections, and inappropriate therapies among drug-induced type 1 BrS patients with transvenous- ICD (TV-ICD) versus subcutaneous-ICD (S-ICD). Data for this study were sourced from the IBRYD (Italian BRugada sYnDrome) registry which includes 619 drug-induced type-1 BrS patients followed at 20 Italian tertiary referral hospitals. For the present analysis, we selected 258 consecutive BrS patients implanted with ICD. 198 patients (76.7%) received a TV-ICD, while 60 a S-ICD (23.4%). And were followed-up for a median time of 84.3 [46.5-147] months. ICD inappropriate therapies were experienced by 16 patients (6.2%). 14 patients (7.1%) in the TVICD group and 2 patients (3.3%) in S-ICD group (log-rank P = 0.64). ICD-related complications occurred in 31 patients (12%); 29 (14.6%) in TV-ICD group and 2 (3.3%) in S-ICD group (log-rank P = 0.41). ICD-related infections occurred in 10 patients (3.88%); 9 (4.5%) in TV-ICD group and 1 (1.8%) in S-ICD group (log-rank P = 0.80). After balancing for potential confounders using the propensity score matching technique, no differences were found in terms of clinical outcomes between the two groups. In a real-world setting of drug-induced type-1 BrS patients with ICD, no significant differences in inappropriate ICD therapies, device-related complications, and infections were shown among S-ICD vs TV-ICD. However, a reduction in lead-related complications was observed in the S-ICD group. In conclusion, our evidence suggests that S-ICD is at least non-inferior to TV-ICD in this population and may also reduce the risk of lead-related complications which can expose the patients to the necessity of lead extractions.

AV junction ablation and cardiac resynchronization for patients with permanent atrial fibrillation and narrow QRS: the APAF-CRT mortality trial.

AIMS: In patients with atrial fibrillation (AF) and heart failure (HF), strict and regular rate control with atrioventricular junction ablation and biventricular pacemaker (Ablation + CRT) has been shown to be superior to pharmacological rate control in reducing HF hospitalizations. However, whether it also improves survival is unknown. METHODS AND RESULTS: In this international, open-label, blinded outcome trial, we randomly assigned patients with severely symptomatic permanent AF >6 months, narrow QRS (≤110 ms) and at least one HF hospitalization in the previous year to Ablation + CRT or to pharmacological rate control. We hypothesized that Ablation + CRT is superior in reducing the primary endpoint of all-cause mortality. A total of 133 patients were randomized. The mean age was 73 ± 10 years, and 62 (47%) were females. The trial was stopped for efficacy at interim analysis after a median of 29 months of follow-up per patient. The primary endpoint occurred in 7 patients (11%) in the Ablation + CRT arm and in 20 patients (29%) in the Drug arm [hazard ratio (HR) 0.26, 95% confidence interval (CI) 0.10-0.65; P = 0.004]. The estimated death rates at 2 years were 5% and 21%, respectively; at 4 years, 14% and 41%. The benefit of Ablation + CRT of all-cause mortality was similar in patients with ejection fraction (EF) ≤35% and in those with >35%. The secondary endpoint combining all-cause mortality or HF hospitalization was significantly lower in the Ablation + CRT arm [18 (29%) vs. 36 (51%); HR 0.40, 95% CI 0.22-0.73; P = 0.002]. CONCLUSIONS: Ablation + CRT was superior to pharmacological therapy in reducing mortality in patients with permanent AF and narrow QRS who were hospitalized for HF, irrespective of their baseline EF. STUDY REGISTRATION: ClinicalTrials.gov Identifier: NCT02137187.

Brugada syndrome and syncope: a practical approach for diagnosis and treatment.

Syncope in patients with Brugada electrocardiogram pattern may represent a conundrum in the decision algorithm because incidental benign forms, especially neurally mediated syncope, are very frequent in this syndrome similarly to the general population. Arrhythmic syncope in Brugada syndrome typically results from a self-terminating sustained ventricular tachycardia or paroxysmal ventricular fibrillation, potentially leading to sudden cardiac death. Distinguishing syncope due to malignant arrhythmias from a benign form is often difficult unless an electrocardiogram is recorded during the episode. We performed a review of the existing literature and propose a practical approach for diagnosis and treatment of the patients with Brugada syndrome and syncope.

Is His-optimized superior to conventional cardiac resynchronization therapy in improving heart failure? Results from a propensity-matched study.

BACKGROUND: His bundle pacing (HBP), alone or optimized in association with coronary sinus pacing (HBP+LV) has recently been proposed as an alternative to conventional cardiac resynchronization therapy (CRT). However, there is lack of controlled studies that assessed clinical outcome. METHODS: We did a single-center, propensity-score matched, case-control study of comparison of HBP and HBP+LV versus conventional CRT in patients with heart failure (HF) and standard indications for CRT. The study group patients were consecutively enrolled in the year 2019. The control group patients were selected, by propensity score matching, among those CRT implantations performed in the years 2015-2018. RESULTS: There were 27 patients in each group. In the active group, 12 (44%) patients received HBP alone and 12 (44%) patients HBP+LV pacing. HBP failed in three (11%) patients. In the control group, conventional CRT was achieved in 26 (96%) patients and failed in one. Paced QRS width was shorter in the active than in the control group (128 ± 18 vs. 148 ± 27 ms, p = .004). During a mean of 9.6 months of follow-up, a composite clinical outcome of death, hospitalization for HF or worsening HF occurred in three (11%) in the active group and in four (15%) in the control group, p = .58. No difference was also observed with softer endpoints: NYHA class (1.9 ± 0.7 vs. 2.1 ± 0.7), subjective improvement (74% vs. 74%) and LV ejection fraction (40.7% vs. 40.7%). CONCLUSION: Compared with conventional CRT, a shorter QRS width can be obtained with HBP alone or in association with coronary sinus pacing but we were unable to show a better clinical outcome. There is urgent need for large, randomized trials.

The arrhythmogenic right ventricular cardiomyopathy in comparison to the athletic heart.

Intense exercise-induced right ventricular remodeling is a potential adaptation of cardiac function and structure. The features of the remodeling may overlap with those of a very early form of arrhythmogenic right ventricular cardiomyopathy (ARVC): at this early stage, it could be difficult to discriminate ARVC, from exercise-induced cardiac adaptation that may develop in normal individuals. The purpose of this paper is to discuss which exercise-induced remodeling may be a pathological or a physiological finding. A complete evaluation may be required to identify the pathological features of ARVC that would include potential risk of sudden cardiac death during sport or, to avoid the false diagnosis of ARVC. The most recent expert assessment of arrhythmogenic cardiomyopathy focuses on endurance athletes presenting with clinical features indistinguishable from ARVC.

Brugada syndrome and syncope: A systematic review.

INTRODUCTION: Distinguishing syncope due to malignant arrhythmias from an incidental benign form in Brugada syndrome (BrS) is often difficult. Through systematic literature review, we evaluated the role of syncope in predicting subsequent malignant arrhythmias in BrS. METHODS: A comprehensive literature search was performed on PubMed (MeSH search terms "Brugada syndrome" and "syncope"). Overall, 9 studies for a total of 1347 patients were included. Patients were stratified as affected by suspected arrhythmic syncope (SAS), undefined syncope (US) or neurally-mediated syncope (NMS). RESULTS: Overall, 15.7% of the 279 patients with SAS had malignant arrhythmic events during a mean follow-up of 67 months, corresponding to 2.8 events per 100/person year. At the same time, 7% of the 527 patients affected by US had malignant arrhythmias during a mean follow-up of 39 months, corresponding 2.2 events per 100/person year. Conversely, 0.7% of 541 patients with NMS had malignant arrhythmic events at follow-up, corresponding to 0.13 events per 100/person year (p = .0001 NMS versus SAS and US pooled). CONCLUSION: In BrS population, the risk of arrhythmic events in the follow-up may be stratified according to the clinical evaluation. The "relatively" low predictive value of the clinical diagnosis of SAS warrants for a more accurate multi-parametric assessment, to restrict the number of candidates for implantable cardioverter-defibrillator therapy.

Atrial fibrillation in Brugada syndrome: Current perspectives.

The incidence of atrial fibrillation (AF) in Brugada syndrome (BrS) has been reported at between 9% and 53% by different series, but the true prevalence is unknown. However, AF may be the presenting feature in some patients. The underlying mechanisms for AF may be a combination of multiple factors, genetic or acquired, that may impact upon autonomic function, atrial structure, and conduction velocities or other unknown factors. The presence of AF has been associated with a more malignant course, with a greater incidence of syncope and ventricular arrhythmias, thus acting as marker of more advanced disease. Regarding the management of patients with AF, antiarrhythmic drugs effective in preventing malignant arrhythmias in BrS such as quinidine or invasive treatment with pulmonary vein isolation (PVI) may be useful in AF treatment. In this review, we aim to present the current perspectives regarding the genetics, pathophysiology, management, and prognosis of AF in patients with BrS.

Frequent Ventricular Premature Beats in Children and Adolescents: Natural History and Relationship with Sport Activity in a Long-Term Follow-Up.

Premature ventricular complexes (PVCs) are frequently documented in children. To date, few studies report long-term follow-up in pediatric cohorts presenting with frequent PVCs. The aim of this study is to assess the clinical relevance and long-term outcomes of frequent PVCs (≥ 500/24 h) in a large pediatric cohort. From 1996 to 2016, we enrolled all consecutive patients evaluated at Anna Meyer Children Hospital for frequent PVCs. Symptomatic children were excluded together with those patients with known underlying heart diseases; thus, our final cohort of study included 103 patients (male 66%; mean age 11 ± 3.4 years), with a mean follow-up of 9.5 ± 5.5 years. All patients were submitted to complete non-invasive cardiologic evaluation. The mean number of PVCs at Holter Monitoring (HM) was 11,479 ± 13,147/24 h; couplets and/or triplets were observed in 5/103 (4.8%) cases; 3 patients (2.9%) presented runs of non-sustained ventricular tachycardia (NSVT). High-burden PVCs (> 30,000/24 h) was confirmed in 11/103 (10.6%) patients. During the follow-up, only five patients (4.8%) developed clinical symptoms (3 for palpitations, 1 myocardial dysfunction due to frequent PVCs and NTSV; 1 arrhythmogenic cardiomyopathy); no deaths occurred. Basal PVCs were still present in 45/103 (43.7%) patients. Our data suggest that frequent PVCs may be addressed as a benign condition and should not preclude sport participation if not associated with cardiac malformations, heart dysfunction, or cardiomyopathy. This seems to be true also in presence of very frequent/high-burden PVCs. Otherwise, a careful follow-up is mandatory since sport eligibility should be reconsidered in case of onset of symptoms and/or ECG/echocardiographic changes.

The influence of age on the psychological profile of patients with cardiac implantable electronic devices: results from the Italian population in a multicenter study conducted by the European Heart Rhythm Association.

BACKGROUND: Cardiac implantable electronic devices (CIEDs) are widely used to treat bradyarrhythmias or improve the prognosis of patients with heart failure (HF). AIMS: To evaluate age-related (≤ 75 vs. > 75 years) attitudes, worries, psychological effects and needs in an Italian CIEDs population. METHODS: Patients attending their periodical ambulatory evaluation received a questionnaire conceived by the European Heart Rhythm Association Scientific Initiatives Committee as part of a multicenter, multinational snapshot survey. Seven countries participated in the study, and 1646 replies were collected. Of these, 437 (27%) were from Italy. Present results refer to the Italian population only. CIEDs were stratified into devices to treat bradycardia or HF. RESULTS: The use of CIEDs was more common in advanced age. Older patients needed less information about CIEDs than younger ones (p = 0.044), who would prefer to be better informed about CIEDs-related consequences on psychologic profile (p = 0.045), physical (p < 0.001) and sexual (p < 0.001) activities, and driving limitations (p = 0.003). When compared to older subjects, younger individuals experienced more difficulties (p = 0.035), especially in their professional (p < 0.001) and private life (p = 0.033), feeling their existence was limited by the device (p < 0.001). Conversely, quality of life (HRQL) more often improved in the elderly (p = 0.001). Information about what to do with CIEDs at the end of life is scant independently of age. CONCLUSIONS: HRQL after CIEDs implantation improves more frequently in older patients, while the psychological burden of CIEDs is usually higher in younger patients. End of life issues are seldom discussed.

The long-QT syndrome and exercise practice: The never-ending debate.

Today, understanding the true risk of adverse events in long-QT syndrome (LQTS) populations may be extremely complex and potentially dependent on many factors such as the affected gene, mutation location, degree of QTc prolongation, age, sex, and other yet unknown factors. In this context, risk stratification by genotype in LQTS patients has been extremely difficult, also during exercise practice, especially due to the lack of studies that would lead to a better understanding of the natural history of each mutation and its impact upon athletes. The creation of individualized guidelines for sport participation is a goal yet to be achieved not only due to the complexity of genotype effect on the phenotype in this patient population, but also due to penetrance in genotype-positive patients. This article summarizes current knowledge and raises questions concerning the difficult relationship between exercise practice and LQTS.

Brugada Syndrome and Exercise Practice: Current Knowledge, Shortcomings and Open Questions.

Since its recognition as a clinical entity in 1992, the Brugada Syndrome (BrS), a hereditary disease characterized by a typical electrocardiogram (ECG) pattern potentially predisposing to sudden cardiac death (SCD), has attracted the attention of many physicians for its circadian pattern of ventricular arrhythmias (VA), mostly occurring at rest. Exercise may potentially worsen the ECG abnormalities in BrS patients, resulting in higher peak J-point amplitudes during the vasovagal reaction of the recovery period, possibly leading to an increased risk of cardiac events. Moreover, the enhanced vagal tone in athletes could be both a BrS risk factor and an exercise effect. Therefore, the true risk of a BrS patient during exercise is still unclear. This review summarizes current knowledge, shortcomings and open questions on BrS and exercise. The paper, in particular, underlines specific considerations including BrS diagnostic criteria and differential diagnosis in athletes, the genetic basis, the autonomic imbalance during exercise practice and the recommendations for athletic participation in this patient group.

Long-term clinical outcomes of patients with drug-induced type 1 Brugada electrocardiographic pattern: A nationwide cohort registry study.

BACKGROUND: There are limited real-world data on the extended prognosis of patients with drug-induced type 1 Brugada electrocardiogram (ECG). OBJECTIVE: We assessed the clinical outcomes and predictors of life-threatening arrhythmias in patients with drug-induced type 1 Brugada ECG. METHODS: This multicenter retrospective study, conducted at 21 Italian and Swiss hospitals from July 1997 to May 2021, included consecutive patients with drug-induced type 1 ECG. The primary outcome, a composite of appropriate ICD therapies and sudden cardiac death, was assessed along with the clinical predictors of these events. RESULTS: A total of 606 patients (mean age 49.7 ± 14.7 years; 423 [69.8%] men) were followed for a median of 60.3 months (interquartile range 23.0-122.4 months). Nineteen patients (3.1%) experienced life-threatening arrhythmias, with a median annual event rate of 0.5% over 5 years and 0.25% over 10 years. The SCN5A mutation was the only predictor of the primary outcome (hazard ratio 4.54; P = .002), whereas a trend was observed for unexplained syncope (hazard ratio 3.85; P = .05). In patients who were asymptomatic at presentation, the median annual rate of life-threatening arrhythmias is 0.24% over 5 years and increases to 1.2% if they have inducible ventricular fibrillation during programmed ventricular stimulation. CONCLUSION: In patients with drug-induced type 1 Brugada ECG, the annual risk of life-threatening arrhythmias is low, with the SCN5A mutation as the only independent predictor. Unexplained syncope correlated with worse clinical outcomes. Ventricular fibrillation inducibility at programmed ventricular stimulation significantly increases the median annual rate of life-threatening arrhythmias from 0.24% to 1.2% over 5 years.

Long-Term Outcomes of Transvenous Lead Extraction: A Comparison in Patients with or without Infection from the Italian Region with the Oldest Population.

BACKGROUND: The gold standard for the treatment of cardiac implantable electronic devices (CIEDs)-related infection and lead malfunction is transvenous lead extraction (TLE). To date, the risk of mortality directly related to TLE procedures is relatively low, but data on post-procedural and long-term mortality are limited, even more in the aging population. METHODS: Consecutive patients with CIEDs who underwent TLE were retrospectively studied. The primary outcome was the endpoint of death, considering independent predictors of long-term clinical outcomes in the TLE aging population comparing patients with and without infection. RESULTS: One hundred nineteen patients (male 77%; median age 76 years) were included in the analysis. Eighty-two patients (69%) documented infection, and thirty-seven (31%) were extracted for a different reason. Infected patients were older (80 vs. 68 years, p-value > 0.001) with more implanted catheters (p-value < 0.001). At the last follow-up (FU) available (median FU 4.1 years), mortality reached 37% of the patient population, showing a statistically significant difference between infected versus non-infected groups. At univariable analysis, age at TLE, atrial fibrillation, and anemia remained significant correlates of mortality; at multivariable analysis, only patients with anemia and atrial fibrillation have a 2.3-fold (HR 2.34; CI 1.16-4.75) and a 2.5-fold (HR 2.46; CI 1.33-4.54) increased rate of death, respectively. CONCLUSION: Our long-term data showed that aging patients who underwent TLE for CIED-related infection exhibit a high mortality risk during a long-term follow-up, potentially leading to a rapid and effective procedural approach in this patient population.

Insight into contact force local impedance technology for predicting effective pulmonary vein isolation.

Background: Highly localized impedance (LI) measurements during atrial fibrillation (AF) ablation have the potential to act as a reliable predictor of the durability of the lesions created. Objective: We aimed to collect data on the procedural parameters affecting LI-guided ablation in a large multicenter registry. Methods: A total of 212 consecutive patients enrolled in the CHARISMA registry and undergoing their first pulmonary vein (PV) isolation for paroxysmal and persistent AF were included. Results: In all, 13,891 radiofrequency (RF) applications of ≥3 s duration were assessed. The first-pass PV isolation rate was 93.3%. A total of 80 PV gaps were detected. At successful ablation spots, baseline LI and absolute LI drop were larger than at PV gap spots (161.4 ± 19â€…Ω vs. 153.0 ± 13 Ω, p < 0.0001 for baseline LI; 22.1 ± 9â€…Ω vs. 14.4 ± 5 Ω, p < 0.0001 for LI drop). On the basis of Receiver operating characteristic curve analysis, the ideal LI drop, which predicted successful ablation, was >21â€…Ω at anterior sites and >18â€…Ω at posterior sites. There was a non-linear association between the magnitude of LI drop and contact-force (CF) (r = 0.14, 95% CI: 0.13-0.16, p < 0.0001) whereas both CF and LI drop were inversely related with delivery time (DT) (-0.22, -0.23 to -0.20, p < 0.0001 for CF; -0.27, -0.29 to -0.26, p < 0.0001 for LI drop). Conclusion: An LI drop >21â€…Ω at anterior sites and >18â€…Ω at posterior sites predicts successful ablation. A higher CF was associated with an increased likelihood of ideal LI drop. The combination of good CF and adequate LI drop allows a significant reduction in RF DT. Clinical trial registration: http://clinicaltrials.gov/, identifier: NCT03793998.

Discordant electrical and mechanical atrial delays affect intracavitary electrogram-based cardiac resynchronization therapy optimization.

AIMS: It has been shown that atrioventricular (AV) delay optimization improves cardiac resynchronization therapy (CRT) response. Recently, an automatic algorithm (QuickOpt™, St Jude Medical), able to quickly identify the individual optimal AV interval, has been developed. The algorithm suggests an AV delay based on atrial intracavitary electrogram (IEGM) duration. We hypothesized that the difference between electrical and mechanical atrial delays could affect the effectiveness of QuickOpt method. The aim of this study was to test this hypothesis in 23 CRT patients who were recipients of St. Jude Medical devices. METHODS AND RESULTS: Using echocardiography, aortic flow velocity time integral (VTI) was evaluated at baseline, at QuickOpt suggested AV delay and after reducing it by 25 and 50%. Mechanical inter-atrial delay (MIAD) derived from echo/Doppler and electrical inter-atrial delay (EIAD) derived from IEGM were also analysed. Optimal AV delay was identified by the maximal VTI. In 11 patients (Group 1) the maximal VTI was achieved at the AV delay suggested by the algorithm, in 6 patients (Group 2) after a 25% reduction, and in 6 patients (Group 3) after a 50% reduction. While EIAD was similar among the three groups, MIAD was significantly different (P< 0.001). MIAD was longer than EIAD in Group 1 (P= 0.028) and shorter than EIAD in Groups 2 (P= 0.028) and 3. (P< 0.001). Mechanical inter-atrial delay was the only independent predictor of the AV interval associated with the best VTI (R(2) = 0.77; P< 0.001). CONCLUSION: Our results show that MIAD plays the main role in determining the optimal AV delay, thus caution should be taken when optimizing AV by IEGM-based methods.