Implantable loop recorders in patients with Brugada syndrome: the BruLoop study.

BACKGROUND AND AIMS: Available data on continuous rhythm monitoring by implantable loop recorders (ILRs) in patients with Brugada syndrome (BrS) are scarce. The aim of this multi-centre study was to evaluate the diagnostic yield and clinical implication of a continuous rhythm monitoring strategy by ILRs in a large cohort of BrS patients and to assess the precise arrhythmic cause of syncopal episodes. METHODS: A total of 370 patients with BrS and ILRs (mean age 43.5 ± 15.9, 33.8% female, 74.1% symptomatic) from 18 international centers were included. Patients were followed with continuous rhythm monitoring for a median follow-up of 3 years. RESULTS: During follow-up, an arrhythmic event was recorded in 30.7% of symptomatic patients [18.6% atrial arrhythmias (AAs), 10.2% bradyarrhythmias (BAs), and 7.3% ventricular arrhythmias (VAs)]. In patients with recurrent syncope, the aetiology was arrhythmic in 22.4% (59.3% BAs, 25.0% VAs, and 15.6% AAs). The ILR led to drug therapy initiation in 11.4%, ablation procedure in 10.9%, implantation of a pacemaker in 2.5%, and a cardioverter-defibrillator in 8%. At multivariate analysis, the presence of symptoms [hazard ratio (HR) 2.5, P = .001] and age >50 years (HR 1.7, P = .016) were independent predictors of arrhythmic events, while inducibility of ventricular fibrillation at the electrophysiological study (HR 9.0, P < .001) was a predictor of VAs. CONCLUSIONS: ILR detects arrhythmic events in nearly 30% of symptomatic BrS patients, leading to appropriate therapy in 70% of them. The most commonly detected arrhythmias are AAs and BAs, while VAs are detected only in 7% of cases. Symptom status can be used to guide ILR implantation.

Endocardial repolarization dispersion in BrS: A novel automatic algorithm for mapping activation recovery interval.

INTRODUCTION: Repolarization dispersion in the right ventricular outflow tract (RVOT) contributes to the type-1 electrocardiographic (ECG) phenotype of Brugada syndrome (BrS), while data on the significance and feasibility of mapping repolarization dispersion in BrS patients are scarce. Moreover, the role of endocardial repolarization dispersion in BrS is poorly investigated. We aimed to assess endocardial repolarization patterns through an automated calculation of activation recovery interval (ARI) estimated on unipolar electrograms (UEGs) in spontaneous type-1 BrS patients and controls; we also investigated the relation between ARI and right ventricle activation time (RVAT), and T-wave peak-to-end interval (Tpe) in BrS patients. METHODS: Patients underwent endocardial high-density electroanatomical mapping (HDEAM); BrS showing an overt type-1 ECG were defined as OType1, while those without (latent type-1 ECG and LType1) received ajmaline infusion. BrS patients only underwent programmed ventricular stimulation (PVS). Data were elaborated to obtain ARI corrected with the Bazett formula (ARIc), while RVAT was derived from activation maps. RESULTS: 39 BrS subjects (24 OType1 and 15 LTtype1) and 4 controls were enrolled. OType1 and post-ajmaline LType1 showed longer mean ARIc than controls (306 ± 27.3 ms and 333.3 ± 16.3 ms vs. 281.7 ± 10.3 ms, p = .05 and p < .001, respectively). Ajmaline induced a significant prolongation of ARIc compared to pre-ajmaline LTtype1 (333.3 ± 16.3 vs. 303.4 ± 20.7 ms, p < .001) and OType1 (306 ± 27.3 ms, p < .001). In patients with type-1 ECG (OTtype1 and post-ajmaline LType1) ARIc correlated with RVAT (r = .34, p = .04) and Tpec (r = .60, p < .001), especially in OType1 subjects (r = .55, p = .008 and r = .65 p < .001, respectively). CONCLUSION: ARIc mapping demonstrates increased endocardial repolarization dispersion in RVOT in BrS. Endocardial ARIc positively correlates with RVAT and Tpec, especially in OType1.

Italian Association of Hospital Cardiologists Position Paper 'Gender discrepancy: time to implement gender-based clinical management'.

It has been well assessed that women have been widely under-represented in cardiovascular clinical trials. Moreover, a significant discrepancy in pharmacological and interventional strategies has been reported. Therefore, poor outcomes and more significant mortality have been shown in many diseases. Pharmacokinetic and pharmacodynamic differences in drug metabolism have also been described so that effectiveness could be different according to sex. However, awareness about the gender gap remains too scarce. Consequently, gender-specific guidelines are lacking, and the need for a sex-specific approach has become more evident in the last few years. This paper aims to evaluate different therapeutic approaches to managing the most common women's diseases.

Does Timing of Ventricular Tachycardia Ablation Affect Prognosis in Patients With an Implantable Cardioverter Defibrillator? Results From the Multicenter Randomized PARTITA Trial.

BACKGROUND: Optimal timing for catheter ablation of ventricular tachycardia is an important unresolved issue. There are no randomized trials evaluating the benefit of ablation after the first implantable cardioverter defibrillator (ICD) shock. METHODS: We conducted a 2-phase, prospective, multicenter, randomized clinical trial. Patients with ischemic or nonischemic dilated cardiomyopathy and primary or secondary prevention indication for ICD were enrolled in an initial observational phase until first appropriate shock (phase A). After reconsenting, patients were randomly assigned 1:1 in phase B to immediate ablation (within 2 months from shock delivery) or continuation of standard therapy. The primary end point was a composite of death from any cause or hospitalization for worsening heart failure. Amiodarone intake was not allowed except for documented atrial tachyarrhythmias. On July 23, 2021, phase B of the trial was interrupted as a result of the first interim analysis on the basis of the Bayesian adaptive design. RESULTS: Of the 517 patients enrolled in phase A, 154 (30%) had ventricular tachycardia, 56 (11%) received an appropriate shock over a median follow-up of 2.4 years (interquartile range, 1.4-4.4), and 47 of 56 (84%) agreed to participate in phase B. After 24.2 (8.5-24.4) months, the primary end point occurred in 1 of 23 (4%) patients in the ablation group and 10 of 24 (42%) patients in the control group (hazard ratio, 0.11 [95% CI, 0.01-0.85]; P=0.034). The results met the prespecified termination criterion of >99% Bayesian posterior probability of superiority of treatment over standard therapy. No deaths were observed in the ablation group versus 8 deaths (33%) in the control group (P=0.004); there was 1 worsening heart failure hospitalization in the ablation group (4%) versus 4 in the control group (17%; P=0.159). ICD shocks were less frequent in the ablation group (9%) than in the control group (42%; P=0.039). CONCLUSIONS: Ventricular tachycardia ablation after first appropriate shock was associated with a reduced risk of the combined death or worsening heart failure hospitalization end point, lower mortality, and fewer ICD shocks. These findings provide support for considering ventricular tachycardia ablation after the first ICD shock. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT01547208.

Electrophysiology fellowship experience and requirements: an EHRA survey.

AIMS: This study aims to survey current educational experience and the individual requirements for electrophysiologists in training. METHODS AND RESULTS: The European Heart Rhythm Association (EHRA) e-Communication Committee and the Scientific Initiatives Committee prepared a questionnaire and distributed it via newsletters, Twitter, LinkedIn, and Facebook. The survey consisted of 22 questions collected on an individual basis anonymously. Two hundred and forty-three responders from 35 countries (32% female, age 38 ± 6 years old) completed the survey. This EHRA electrophysiology (EP) fellowship survey showed that (i) hands-on participation and observation of EP procedures are very important; (ii) the main motivations to choose the EP fellowship institution are centre reputation and volume as well as the availability of a structured EP fellowship programme; (iii) 59% passed the EHRA exam and 46% took a national certification exam; (iv) respondents are overall satisfied with their own fellowships, but there are areas of less confidence such as conduction system pacing implantation and cardiac resynchronization therapy implantation; (v) 78% of respondents performed research during their fellowship, (vi) the optimal duration of an EP fellowship should be at least 2 years; and (viii) doing fellowships abroad is beneficial, but significant obstacles exist. CONCLUSION: The results of this EHRA survey may help to refine current EP fellowship programmes to improve the quality of EP training and early career building of young electrophysiologists.

Occupational radiation exposure of electrophysiology staff with reproductive potential and during pregnancy: an EHRA survey.

AIMS: Electrophysiology (EP) is a growing field in cardiology, with an increasing involvement of young people. Nevertheless, concerns about radiation exposure and its impact on reproduction and pregnancy may discourage the choice of an EP career. The study is aimed at investigating the level of awareness and main sources of concern about the effects of radiation on reproductive potential and pregnancy, exploring the safety measures adopted in different EP labs, and verifying the adherence to the current guidelines. METHODS AND RESULTS: An online survey was conducted using the European Heart Rhythm Association (EHRA) infrastructure from April to June 2022. A total of 252 EP personnel (42% women) participated, from 50 countries and different professional roles. Most participants expressed concerns regarding the effects of radiation on reproductive capacity (67.1%) and offspring diseases (68.2%). Only 37.9% of participants were aware of the EHRA 2017 consensus document about occupational radiation exposure. Most participants (80.9%) considered that occupational radiation during pregnancy is not safe. EP female staff were not allowed to work in the EP lab during pregnancy in 48.1% of cases. Zero-fluoroscopy was the preferred choice to continue working in the EP lab during pregnancy. CONCLUSION: EP staff, including both men and women, have concerns about the effects of radiation on reproductive capacity. Despite the recommendations issued by international bodies, implementation of the policies regarding pregnancy and occupational radiation exposure is heterogeneous. Zero-fluoroscopy is the preferred approach to ensure safety during pregnancy in the EP lab.

Prognostic value of right ventricular refractory period heterogeneity in Type-1 Brugada electrocardiographic pattern.

AIMS: To investigate the prognostic significance of heterogeneity in the refractoriness of right ventricular (RV) outflow tract (RVOT) and RV apex at the electrophysiological study (EPS) in Brugada syndrome (BrS). METHODS AND RESULTS: A cohort of BrS patients (primary prevention) from five Italian centres was retrospectively analysed. Patients with spontaneous or drug-induced Type-1 electrocardiogram (ECG) + symptoms were offered an EPS for prognostic stratification. The primary endpoint was a composite of sudden cardiac death (SCD), resuscitated cardiac arrest, or appropriate intervention by the implantable cardioverter-defibrillator (ICD). Three hundred and seventy-two patients with BrS were evaluated (44 ± 15 years, 69% males, 23% with ICD): 4 SCDs and 17 ICD interventions occurred at follow-up (median 48, interquartile range: 36-60 months). Family history of SCD, syncope, and a spontaneous Type-1 ECG pattern were univariate predictors of the primary endpoint in the whole population. In patients undergoing EPS (n = 198, 53%, 44 ± 12 years, 71% males, 39% with ICD), 3 SCD and 15 ICD interventions occurred at follow-up. In this subset, the primary endpoint was not only predicted by ventricular tachycardia/fibrillation inducibility but also by a difference in the refractory period between RVOT and RV apex (ΔRPRVOT-apex) >60 ms. ΔRPRVOT-apex > 60 ms remained an independent predictor of SCD/ICD shock at bivariate analysis, even when adjusted for the other univariate predictors, showing the highest predictive power at C-statistic analysis (0.75, 95% confidence interval 0.63-0.86). CONCLUSIONS: Heterogeneity of RV refractory periods is a strong, independent predictor of life-threatening arrhythmias in BrS patients, beyond VT/VF inducibility at EPS and common clinical predictors.

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.

Worldwide sedation strategies for atrial fibrillation ablation: current status and evolution over the last decade.

Catheter ablation for atrial fibrillation (AF) has become one of the most common procedures in the electrophysiology lab with rapidly increasing volumes. Peri-procedural anaesthesia for AF ablation varies between centres, from general anaesthesia to deep or conscious sedation. The aim of this survey was to assess current sedation practices for AF ablation worldwide and its evolution over the last decade. Centres regularly performing AF ablation responded to an online survey. A total of 297 centres participated in the survey. Overall, the median (interquartile range) number of AF ablation procedures increased from 91 (43-200) to 200 (74-350) per year (P < 0.001) between 2010 and 2019. The proportion of cryoablation also increased from 17.0% to 33.2% (P < 0.001). In 2019, the most used sedation technique was general anaesthesia (40.5%), followed by conscious sedation (32.0%) and deep sedation (27.5%). Between 2010 and 2019, the proportion of procedures performed under general anaesthesia (+4.4%; P = 0.02) and deep sedation (+4.8%; P < 0.01) increased, whereas the use of conscious sedation decreased (-9.2%; P < 0.001). The most commonly used hypnotic drugs were propofol and midazolam, whereas the most commonly used opioid drugs were remifentanyl and fentanyl. This worldwide survey shows that the number of AF ablation procedures has more than doubled over the last decade and general anaesthesia remains most commonly used. Studies comparing outcomes between different sedation strategies are needed to guide optimal decision-making.

Cardiac Resynchronization Therapy in Patients with Heart Failure: What is New?

Cardiac resynchronization therapy (CRT) is an established treatment of patients with medically refractory, mild-to-severe systolic heart failure (HF), impaired left ventricular function, and wide QRS complex. The pathologic activation sequence observed in patients with abnormal QRS duration and morphology results in a dyssynchronous ventricular activation and contraction leading to cardiac remodeling, worsening systolic and diastolic function, and progressive HF. In this article, the authors aim to explore the current CRT literature, focusing their attentions on the promising innovation in this field.

Electroanatomic mapping-guided endomyocardial biopsy in patients with apparently idiopathic ventricular arrhythmias.

The management of ventricular arrhythmias (VA) in the presence of an apparently normal heart represents a major clinical challenge and a main field of clinical research. In the past years, new imaging techniques and the spreading of new generation genetic testing have improved our knowledge of the pathogenesis of apparently idiopathic VA. However, in the absence of specific recommendations, the type and the number of noninvasive and invasive studies necessary to rule out a possible underlying cause of VA or sudden cardiac death remain extremely variable. Therefore, in many patients the underlying cardiac disease is not recognized, and a possible specific therapeutic approach cannot be initiated. Endomyocardial biopsy (EMB) can provide a significant contribution to the identification of myocardial disorders causing VA but has never been definitively included in the routine diagnostic work-up of these patients due to the possible sampling error particularly in disorders with a focal or patchy distribution. Three-dimensional electroanatomic mapping (EAM) may guide EMB allowing to draw myocardial samples from abnormal voltage, areas of the ventricular wall, thus reducing sampling error and increasing the sensitivity of EMB. The systematic association of EAM with EMB represents a crucial approach to characterize the pathological substrate of electroanatomic abnormalities and VA and to further clarify the arrhythmogenic mechanisms of acquired and also inherited arrhythmic disorders.

Contact-force monitoring increases accuracy of right ventricular voltage mapping avoiding "false scar" detection in patients with no evidence of structural heart disease.

PURPOSE: Electroanatomical mapping (EAM) could increase cardiac magnetic resonance imaging (CMR) sensitivity in detecting ventricular scar. Possible bias may be scar over-estimation due to inadequate tissue contact. Aim of the study is to evaluate contact-force monitoring influence during EAM, in patients with idiopathic right ventricular arrhythmias. METHODS: 20 pts (13 M; 43 ± 12 y) with idiopathic right ventricular outflow tract (RVOT) arrhythmias and no structural abnormalities were submitted to Smarttouch catheter Carto3 EAM. Native maps included points collected without considering contact-force. EAM scar was defined as area ≥1 cm2 including at least 3 adjacent points with signal amplitude (bipolar <0.5 mV, unipolar 3,5 mV), surrounded by low-voltage border zone. EAM were re-evaluated offline, removing points collected with contact force <5 g. Finally, contact force-corrected maps were compared to the native ones. RESULTS: An EAM was created for each patient (345 ± 85 points). After removing poor contact points, a mean of 149 ± 60 points was collected. The percentage of false scar, collected during contact force blinded mapping compared to total volume, was 6.0 ± 5.2% for bipolar scar and 7.1 ± 5.9% for unipolar scar, respectively. No EAM scar was present after poor contact points removal. Right ventricular areas analysis revealed a greater number of points with contact force < 5 g acquired in free wall, where reduced mean bipolar and unipolar voltage were recorded. CONCLUSIONS: To date this is the first work conducted on structurally normal hearts in which contact-force significantly increases EAM accuracy, avoiding "false scar" related to non-adequate contact between catheter and tissue.

Cardiac Resynchronization Therapy: An Overview on Guidelines.

Cardiac resynchronization therapy (CRT) is included in international consensus guidelines as a treatment with proven efficacy in well-selected patients on top of optimal medical therapy. Although all the guidelines strongly recommend CRT for LBBB with QRS duration greater than 150 milliseconds, lower strength of recommendation is reported for QRS duration of 120 to 150 milliseconds, especially if not associated with LBBB. CRT is not recommended for a QRS of less than 120 milliseconds. No indication emerges for guiding the implant based on echocardiographic evaluation of dyssynchrony. Many data indicate that CRT is underused and there is heterogeneity in its implementation.

Autoantibodies against ß1-Adrenergic Receptors: Response to Cardiac Resynchronization Therapy and Renal Function.

BACKGROUND: Cardiac resynchronization therapy (CRT) nonresponse remains a major clinical problem. Autoantibodies specific for the ß1-adrenergic (ß1-AAbs) and muscarinic (M2-AAbs) receptors are found in patients with chronic heart failure (HF) of various etiologies. MATERIALS AND METHODS: We retrospectively analyzed 73 HF patients (median age 67 years, 84% males, New York Heart Association II-IV, in sinus rhythm, left ventricular ejection fraction <35%) who received CRT defibrillator (CRT-D) from 2010 to 2013. ß1-AAbs and M2-AAbs were measured by enzyme-linked immunosorbent assay. Echocardiography was used to assess CRT response (reduction >15% in left ventricular end-systolic volume at 6 months follow-up). Renal function (RF) parameters (creatinine [Cr], blood urea nitrogen [BUN], estimated glomerular filtration rate [eGFR Modified Diet in Renal Disease], cystatin C [Cys-C], and neutrophil gelatinase-associated lipocalin [NGAL]) were also evaluated. RESULTS: A significantly higher percentage of patients positive for ß1-AAbs (OD sample/OD reference ratio >2.1) in nonresponders than in responder patients was observed (57% vs 27%, P = 0.004). No influence of M2-AAbs on CRT-D response was demonstrated. ß1-AAbs were predictive of a poor CRT-D response (odds ratio [OR] [95% confidence interval (CI)] 3.64 [1.49-8.88], P = 0.005), also after adjustment for RF parameters (OR [95% CI] 4.95 [1.51-16.26], P = 0.008) observed to influence CRT-D response (Cr P = 0.03, BUN P = 0.009, Cys-C P = 0.02). The positive rates of ß1-AABs in patients with abnormal blood level of Cr, eGFR, Cys-C, and NGAL were significantly higher than those with normal levels (P = 0.03, P = 0.02, P = 0.001, P = 0.007, respectively). CONCLUSIONS: Our study suggests that (1) the evaluation of ß1-AAb is useful to identify responders to CRT-D; (2) the presence of ß1-AAbs is in relationship with elevated renal function parameters.

Cardiac memory in cardiac resynchronization therapy: A vectorcardiographic comparison of biventricular and left ventricular pacing.

INTRODUCTION: "Cardiac memory" (CM) refers to a change in repolarization induced by an altered pathway of activation, manifested after resumption of spontaneous ventricular activation (SVA). AIMS: To investigate for the first time in humans the effects of left ventricular (LV) pacing on CM development through vectorcardiography (VCG). METHODS: We studied 28 patients with heart failure (HF) and left bundle branch block (LBBB) treated with cardiac resynchronization therapy (CRT). Fourteen patients underwent biventricular (BIV) stimulation; the other 14 underwent LV stimulation only. VCG was acquired during SVA at baseline and during AAI and DDD pacing immediately after and 7 and 90 days after the implant. RESULTS: At baseline, in both groups, the QRS and T vectors angles were those specific of LBBB pattern. During DDD pacing, QRS vector angle changed to the right and upward in BIV patients while no significant differences were observed in LV patients. During AAI pacing, T vector angle changed significantly in BIV patients, following the direction of the paced QRS and amplitude significantly increased. In LV patients no significant differences in T vector angles were observed. Only T vector amplitude significantly increased at 7 days (p=0.03) and at 90 days (p=0.008 vs baseline). CONCLUSION: In patients with LBBB, BIV pacing induces cardiac memory development as a significant change in T vector magnitude and angle, while LV pacing doesn't induce significant modifications in QRS and T vector angles and CM is manifested only as a significant T vector amplitude change.

Hyperglycemia, acute insulin resistance, and renal dysfunction in the early phase of ST-elevation myocardial infarction without previously known diabetes: impact on long-term prognosis.

We evaluated the relationship between admission renal function (as assessed by estimated glomerular filtration rate (eGFR)), hyperglycemia, and acute insulin resistance, indicated by the homeostatic model assessment (HOMA) index, and their impact on long-term prognosis in 825 consecutive patients with ST-elevation myocardial infarction (STEMI) without previously known diabetes who underwent primary percutaneous coronary intervention (PCI). Admission eGFR showed a significant indirect correlation with admission glycemia (Spearman's ρ -0.23, P < 0.001) and insulin values (Spearman's ρ -0.11, P = 0.002). The incidence of patients with admission glycemia ≥140 mg/dl was significantly higher in patients with eGFR <60 ml/min/m(2) (P < 0.001) as well as the incidence of HOMA positivity (P = 0.002). According to our data, a relationship between renal function and glucose values and acute insulin resistance in the early phase of STEMI was detectable, since a significant, indirect correlation between eGFR, insulin values, and glycemia was observed. Patients with renal dysfunction (eGFR <60 ml/min/1.73 m(2)) exhibited higher glucose values and a higher incidence of acute insulin resistance (as assessed by HOMA index) than those with normal renal function (eGFR ≥60 ml/min/1.73 m(2)). The prognostic role of glucose values for 1-year mortality was confined to patients with eGFR ≥60 ml/min/m(2), who represent the large part of our population and are thought to be at lower risk. In these patients, an independent relationship between 1-year mortality and glucose values was detectable not only for admission glycemia but also for glucose values measured at discharge.

Double-balloon venous ethanol ablation for treatment of repetitive monomorphic ventricular complexes from intramural infero-basal septum: a case report.

Background: Ablation failures are common in case of intramural location of the arrhythmogenic substrate. Case summary: We report the case of a patient with cardiomyopathy contributed by frequent monomorphic ventricular arrhythmias (VAs) from intramural basal interventricular septum treated with double-balloon venous ethanol ablation (VEA) after a previous failed endocardial radiofrequency (RF) ablation. Discussion: Double-balloon VEA represents a safe and effective therapeutic option in case of intramural VAs also in the absence of venous collaterals joining selectively an intramural arrhythmic substrate.

[New frontiers in pacing: from myocardial pacing to conduction system pacing]. / Nuove frontiere dell'elettrostimolazione: dal pacing del miocardio comune al pacing del sistema di conduzione.

For many years, cardiac pacing has been based on the stimulation of right ventricular common myocardium to correct diseases of the conduction system. The birth and the development of cardiac resynchronization have led to growing interest in the correction and prevention of pacing-induced dyssynchrony. Many observational studies and some randomized clinical trials have shown that conduction system pacing (CSP) can not only prevent pacing-induced dyssynchrony but can also correct proximal conduction system blocks, with reduction of QRS duration and with equal or greater effectiveness than biventricular pacing. Based on these results, many Italian electrophysiologists have changed the stimulation target from the right ventricular common myocardium to CSP. The two techniques with greater clinical impact are the His bundle stimulation and the left bundle branch pacing. The latter, in particular, because of its easier implantation technique and better electric parameters, is spreading like wildfire and is representing a real revolution in the cardiac pacing field. However, despite the growing amount of data, until now, the European Society of Cardiology guidelines give a very limited role to CSP.

Electrocardiographic predictors of left ventricular scar in athletes with right bundle branch block premature ventricular beats.

AIMS: Right bundle branch block (RBBB) morphology non-sustained ventricular arrhythmias (VAs) have been associated with the presence of non-ischaemic left ventricular scar (NLVS) in athletes. The aim of this cross-sectional study was to identify clinical and electrocardiogram (ECG) predictors of the presence of NLVS in athletes with RBBB VAs. METHODS AND RESULTS: Sixty-four athletes [median age 39 (24-53) years, 79% males] with non-sustained RBBB VAs underwent cardiac magnetic resonance (CMR) with late gadolinium enhancement in order to exclude the presence of a concealed structural heart disease. Thirty-six athletes (56%) showed NLVS at CMR and were assigned to the NLVS positive group, whereas 28 athletes (44%) to the NLVS negative group. Family history of cardiomyopathy and seven different ECG variables were statistically more prevalent in the NLVS positive group. At univariate analysis, seven ECG variables (low QRS voltages in limb leads, negative T waves in inferior leads, negative T waves in limb leads I-aVL, negative T waves in precordial leads V4-V6, presence of left posterior fascicular block, presence of pathologic Q waves, and poor R-wave progression in right precordial leads) proved to be statistically associated with the finding of NLVS; these were grouped together in a score. A score ≥2 was proved to be the optimal cut-off point, identifying NLVS athletes in 92% of cases and showing the best accuracy (86% sensitivity and 100% specificity, respectively). However, a cut-off ≥1 correctly identified all patients with NLVS (absence of false negatives). CONCLUSION: In athletes with RBBB morphology non-sustained VAs, specific ECG abnormalities at 12-lead ECG can help in detecting subjects with NLVS at CMR.

In athletes with right bundle branch block (RBBB) morphology non-sustained ventricular arrhythmias (VAs), the presence of a non-ischaemic left ventricular scar (NLVS) may be highly suspected if one or more of the following electrocardiogram (ECG) characteristics are present at the 12-lead resting ECG: low QRS voltages in limb leads, negative T waves in inferior leads, negative T waves in limb leads I­aVL, negative T waves in precordial leads V4­V6, presence of left posterior fascicular block, presence of pathologic Q waves, and poor R-wave progression in right precordial leads. This score should be externally validated in a larger population of athletes with VAs. In athletes with RBBB morphology non-sustained Vas, attention should be placed on the 12-lead resting ECG to suspect the presence of an NLVS. In athletes with RBBB VAs and the presence of one or more of the identified ECG characteristics, a cardiac magnetic resonance with late gadolinium enhancement is useful to rule out an NLVS.