Echo state networks for the recognition of type 1 Brugada syndrome from conventional 12-LEAD ECG.

Artificial Intelligence (AI) applications and Machine Learning (ML) methods have gained much attention in recent years for their ability to automatically detect patterns in data without being explicitly taught rules. Specific features characterise the ECGs of patients with Brugada Syndrome (BrS); however, there is still ambiguity regarding the correct diagnosis of BrS and its differentiation from other pathologies. This work presents an application of Echo State Networks (ESN) in the Recurrent Neural Networks (RNN) class for diagnosing BrS from the ECG time series. 12-lead ECGs were obtained from patients with a definite clinical diagnosis of spontaneous BrS Type 1 pattern (Group A), patients who underwent provocative pharmacological testing to induce BrS type 1 pattern, which resulted in positive (Group B) or negative (Group C), and control subjects (Group D). One extracted beat in the V2 lead was used as input, and the dataset was used to train and evaluate the ESN model using a double cross-validation approach. ESN performance was compared with that of 4 cardiologists trained in electrophysiology. The model performance was assessed in the dataset, with a correct global diagnosis observed in 91.5 % of cases compared to clinicians (88.0 %). High specificity (94.5 %), sensitivity (87.0 %) and AUC (94.7 %) for BrS recognition by ESN were observed in Groups A + B vs. C + D. Our results show that this ML model can discriminate Type 1 BrS ECGs with high accuracy comparable to expert clinicians. Future availability of larger datasets may improve the model performance and increase the potential of the ESN as a clinical support system tool for daily clinical practice.

ANMCO position paper: guide to the appropriate use of the wearable cardioverter defibrillator in clinical practice for patients at high transient risk of sudden cardiac death.

Extended risk stratification and optimal management of patients with a permanently increased risk of sudden cardiac death (SCD) are becoming increasingly important. There are several clinical conditions where the risk of arrhythmic death is present albeit only transient. As an example, patients with depressed left ventricular function have a high risk of SCD that may be only transient if there will be a significant recovery of function. It is important to protect the patients while receiving and titrating to the optimal dose the recommended drugs that may lead to an improved left ventricular function. In several other conditions, a transient risk of SCD can be observed even if the left ventricular function is not compromised. Examples are patients with acute myocarditis, during the diagnostic work-up of some arrhythmic conditions or after extraction of infected catheters while eradicating the associated infection. In all these conditions, it is important to offer a protection to these patients. The wearable cardioverter defibrillator (WCD) is of particular importance as a temporary non-invasive technology for both arrhythmia monitoring and therapy in patients with increased risk of SCD. Previous studies have shown the WCD to be an effective and safe therapy for the prevention of SCD caused by ventricular tachycardia/fibrillation. The aim of this ANMCO position paper is to provide a recommendation for clinical utilization of the WCD in Italy, based upon current data and international guidelines. In this document, we will review the WCD functionality, indications, clinical evidence, and guideline recommendations. Finally, a recommendation for the utilization of the WCD in routine clinical practice will be presented, in order to provide physicians with a practical guidance for SCD risk stratification in patients who may benefit from this device.

[ANMCO Position paper: Wearable cardioverter defibrillator appropriate use guidance for the management of patients at high transient risk of sudden cardiac death]. / Position paper ANMCO: Guida all'uso appropriato del defibrillatore indossabile nella pratica clinica per i pazienti ad elevato rischio transitorio di morte improvvisa.

Extended risk stratification and optimal management of patients with a permanently increased risk of sudden cardiac death (SCD) is becoming increasingly important. There are several clinical conditions where the risk of arrhythmic death is present albeit only transient. As an example, patients with depressed left ventricular function have a high risk of SCD that may be only transient when there is a significant recovery of function. It is important to protect the patients while receiving the recommended measures and drugs that may either lead or not to an improved left ventricular function. In several other conditions a transient risk of SCD can be observed even if the left ventricular function is not compromised. Examples are patients with acute myocarditis, during the diagnostic work-up of some arrhythmic conditions or after extraction of infected catheters while eradicating the associated infection. In all these conditions it is important to offer a protection to these patients. The wearable cardioverter-defibrillator (WCD) is of particular importance as a temporary non-invasive technology for both arrhythmia monitoring and therapy in patients with increased risk of SCD. Previous studies have shown the WCD to be an effective and safe therapy for the prevention of SCD caused by ventricular tachycardia/fibrillation. The aim of this ANMCO position paper is to provide a recommendation for clinical utilization of the WCD in Italy, based upon current data and international guidelines. In this document we will review the WCD functionality, indications, clinical evidence as well as guideline recommendations. Finally, a recommendation for the utilization of the WCD in routine clinical practice will be presented, in order to provide physicians with a practical guidance for SCD risk stratification in patients who may benefit from this device.

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.

Case Series: Recovery of Chemotherapy-Related Acute Heart Failure by the Combined Use of Sacubitril Valsartan and Wearable Cardioverter Defibrillator: A Novel Winning Combination in Cardio-Oncology.

Effective anticancer treatments have dramatically improved the outcome of patients with cancer, but cardiac toxicity reduces their clinical efficacy in a non-negligible percentage of patients. Sacubitril/valsartan is a new paradigm in the treatment of chronic heart failure, with a reduced ejection fraction due to the enhancement of natriuretic peptides' properties when coupled with a blocking effect on the angiotensin II type 1 (AT1) receptors. As with other clinical conditions of heart failure with potentially reversible declines in cardiac function, a wearable cardioverter defibrillator (WCD) is a valid tool for protection against sudden death until recovery occurs. We report a case series of four patients with chemotherapy-related acute cardiac failure with severely reduced cardiac function. They were successfully treated with sacubitril/valsartan while being protected from malignant arrhythmias using a wearable cardioverter defibrillator until the recovery of cardiac function. Sacubitril/valsartan was confirmed to be effective in anthracycline-related cardiac toxicity and the wearable cardioverter defibrillator should be considered as a support tool even in the oncology patient.

Prolonged care delivery time and reduced rate of electrophysiological procedures during the lockdown period due to Covid-19 outbreak.

OBJECTIVES: The aim of this study is to demonstrate how Electrophysiology activity has been impacted by the pandemic Coronavirus disease 2019 (COVID-19). METHODS: In this multicenter retrospective study, we analyze all consecutive patients admitted for electrophysiological procedures during the COVID-19 lockdown in the Tuscany region of Italy, comparing them to patients hospitalized in the corresponding period of the previous year. RESULTS: The impact of COVID-19 on cardiac arrhythmia management was impressive, with a reduction of more than 50% in all kinds of procedures. A gender gap was observed, with a more relevant reduction for female patients. Arrhythmic urgencies requiring a device implant showed a reduced time from symptoms to first medical contact but the time from first medical contact to procedure was significantly prolonged. CONCLUSION: Hospitals need to consider how outbreaks may affect health systems beyond the immediate infection. Routine activity should be based on a risk assessment between the prompt performance of procedure and its postponement. Retrospective observational analysis such as this study could be decisive in evidence-based medicine of any future pathogen outbreak.Nonstandard Abbreviations and Acronyms PM= pacemakerICD= implantable cardioverter defibrillatorECV= electrical cardioversionEPS= electrophysiological studyAP= ablations proceduresCIED= cardiac implantable electronic devicesWCD= wearable cardioverter defibrillatorEP Lab= Electrophysiology LaboratoriesAVNRT =atrioventricular nodal reentry tachycardiaAVRT= atrioventricular reentry tachycardiaAFL= atrial flutterAF= atrial fibrillationVT= ventricular tachycardiaAT= atrial tachycardia.

Diagnostic and Prognostic Role of Cardiac Magnetic Resonance Before Implantable Cardioverter Defibrillator.

The use of cardiac magnetic resonance (cMR) to assess remodeling and tissue characterization in primitive and secondary cardiomyopathies has progressively increased, and it carries important prognostic informations. The aim of this study was to assess the overall clinical value of cMR before implantable cardioverter defibrillator (ICD). All patients referred to our center for an ICD implantation and submitted to cMR (n = 134) were analyzed. All the cMR diagnostic findings and following clinical events were reviewed to assess clinical relevance in patients care. The use of cMR before ICD implantation has progressively increased during the decade studied (13% to 53%, p <0.001). Subjects who underwent cMR were younger, more often female, with lower NYHA class and higher ejection fraction (p <0.05 for all). Unexpected diagnostic findings were observed in 34 patients (25%), resulting in an immediate therapeutic strategy modification in 13%. A pattern of fibrosis leading to a change in the disease's etiology and thrombus detection were the most frequent cMR findings, followed by anatomical incidental findings. Any grade of fibrosis carried a higher annual incidence of combined death or ventricular arrhythmias (9.92% vs 1.83%, p = 0.02). Annual event rate was related to the extent of scarring. In conclusion, we observed a progressively increase of cMR utilization before ICD implantation during the last decade. This practice has yielded a significant increase of new diagnostic findings, carrying unique prognostic information linked to tissue characterization.

Cardiac resynchronization therapy after coronary sinus lead extraction: feasibility and mid-term outcome of transvenous reimplantation in a tertiary referral centre.

AIMS: Few data are available on cardiac resynchronization therapy (CRT) after coronary sinus (CS) lead extraction. We aimed to evaluate the feasibility and mid-term outcome of transvenous CS lead reimplantation in a tertiary referral centre. METHODS AND RESULTS: We enrolled all patients who were referred to our hospital for CS lead removal from December 2000 through to May 2009 and were transvenously reimplanted with a CRT system before June 2009. One-year follow-up was performed to evaluate the incidence of infections, malfunctions, and mortality. We studied 113 consecutive patients undergoing successful CS lead extraction; 90 patients (75 male, mean age 69.2, range 35-84) underwent CS lead reimplantation (success rate: 95.6%; right-sided approach: 64.4%). In these patients, cardiac device infection was the usual indication for extraction (74.4%) and the subsequent reimplantation was performed after a median time of 3 days. The coronary sinus lead was usually positioned in the left ventricular (LV) postero-lateral region (62.2%); two procedures were required in two cases (2.2%). Balloon angioplasty was necessary for two patients (failure in one), whereas for the others we used a conventional implant technique. During follow-up, we observed four cases (4.4%) of local infection and six cases (6.7%) of system malfunction, requiring reintervention (two cases during the same hospitalization). One-year mortality was 5.5%. CONCLUSION: Left ventricular lead reimplantation is in our experience an effective and safe procedure, also in the case of right-sided approach. During follow-up, 1-year mortality was particularly low, whereas overall infection rate was higher than first implant procedures.

Role of intraoperative electrical parameters in predicting reverse remodelling after cardiac resynchronization therapy and correlation with interventricular mechanical dyssynchrony.

AIMS: Cardiac resynchronization therapy (CRT) was shown to reverse left ventricular (LV) remodelling in heart failure (HF) patients. We aimed to investigate whether intraoperative electrical parameters (IEP) were predictive factors of LV reverse remodelling and were correlated with mechanical dyssynchrony indexes. METHODS: Eighty-six patients with HF underwent CRT. At implant, several electrical and echocardiographic parameters were evaluated and, at 6 months, responders were defined by a relative increase in LV ejection fraction ≥25% compared with baseline. RESULTS: Several IEPs were shown to predict LV reverse remodelling. Receiver operating curve analysis revealed the ratio between QRS duration during biventricular pacing (BVp) and right ventricular pacing (RVp) [QRS(BVp)/QRS(RVp)] as the best predictor of LV functional recovery after CRT (AUC = 0.72; 95% confidence limit 0.57-0.82; P < 0.001). Responders showed a lower value of QRS(BVp)/QRS(RVp) when compared with non-responders (0.74 ± 0.05 vs. 0.8 ± 0.1; P < 0.005) and 0.78 was the value associated with the best predictive accuracy. The interval between the onset of RV lead and LV lead electrograms (RVegm-LVegm) during baseline rhythm correlated directly with the interventricular mechanical delay (IVMD) (r = 0.68; P < 0.0001) and with its reduction (delta IVMD) at follow-up (r = 0.66; P < 0.0005). CONCLUSION: Intraoperative electrical parameters can predict LV functional recovery after CRT and they are correlated with interventricular mechanical resynchronization at follow-up.

[Iatrogenic risk of permanent pacemaker and defibrillator implantation]. / II rischio iatrogeno connesso all'impianto di pacemaker e defibrillatori.

The considerable evolution in technique and hardware, occurred over the past three decades, has greatly simplified the implantation procedure of pacemakers and cardioverter-defibrillators. Indeed, the introduction of relatively simple and safe methods of central venous access, and the miniaturization of the generator with subcutaneous placement have facilitated the implantation. However, inherent with cardiac pacing and defibrillating therapy is the potential for the occurrence of an early or delayed untoward event. Although skill, experience, and technique are all mitigating factors, every cardiologist should know potential complications and should be able to stratify overall risk related to a device implantation. Thus, both the implanting physician or the clinical cardiologist must be concerned not only with measures to avoid complications, but also with their early recognition and treatment.

Transvenous removal of pacing and implantable cardiac defibrillating leads using single sheath mechanical dilatation and multiple venous approaches: high success rate and safety in more than 2000 leads.

AIMS: The aim of the present study was to describe a 10 years single-centre experience in pacing and defibrillating leads removal using an effective and safe modified mechanical dilatation technique. METHODS AND RESULTS: We developed a single mechanical dilating sheath extraction technique with multiple venous entry site approaches. We performed a venous entry site approach (VEA) in cases of exposed leads and an alternative transvenous femoral approach (TFA) combined with an internal transjugular approach (ITA) in the presence of very tight binding sites causing failure of VEA extraction or in cases of free-floating leads. We attempted to remove 2062 leads [1825 pacing and 237 implantable cardiac defibrillating (ICD) leads; 1989 exposed at the venous entry site and 73 free-floating] in 1193 consecutive patients. The VEA was effective in 1799 leads, the TFA in 28, and the ITA in 205; in the overall population, we completely removed 2032 leads (98.4%), partially removed 18 (0.9%), and failed to remove 12 leads (0.6%). Major complications were observed in eight patients (0.7%), causing three deaths (0.3%). CONCLUSION: Mechanical single sheath extraction technique with multiple venous entry site approaches is effective, safe, and with a good cost effective profile for pacing and ICD leads removal.

Radiofrequency catheter ablation of atrioventricular nodal reciprocating tachycardia using intracardiac echocardiography in pregnancy.

We describe a case report of a 32-year-old woman during the 10th week of pregnancy with symptomatic and recurrent atrioventricular nodal reciprocating tachycardia successfully treated by conventional radiofrequency ablation, under intracardiac echocardiography surveillance.