SGLT2i effect on atrial fibrillation: A network meta-analysis of randomized controlled trials.

INTRODUCTION: Gliflozins are recommended as first-line treatment in patients with heart failure and/or cardiovascular comorbidities and are demonstrated to reduce atrial fibrillation (AF) occurrence. However, it is not well known which gliflozin yields the larger cardioprotection in terms of AF occurrence reduction. Hence, we aimed to compare data regarding AF recurrence associated with different gliflozins. METHODS: An accurate search of online scientific libraries (from inception to June 1, 2023) was performed. Fifty-nine studies were included in the meta-analysis involving 108 026 patients, of whom 60 097 received gliflozins and 47 929 received placebo. RESULTS: Gliflozins provided a statistically significant reduction of AF occurrence relative to standard of care therapy in the overall population (relative risks [RR]: 0.8880, 95% CI: [0.8059; 0.9784], p = .0164) and in patients with diabetes and cardiorenal diseases (RR: 0.8352, 95% CI: [0.7219; 0.9663], p = .0155). Dapagliflozin significantly decreased AF occurrence as compared to placebo (0.7259 [0.6337; 0.8316], p < .0001) in the overall population, in patients with diabetes (RR: 0.2482, 95% CI: [0.0682; 0.9033], p = .0345), with diabetes associated with cardiorenal diseases (RR: 0.7192, 95% CI: [0.5679; 0.9110], p = .0063) and in the subanalysis including studies with follow-up ≥1 year (RR: 0.7792, 95% CI: [0.6508; 0.9330], p = .0066). No significant differences in terms of AF protection were found among different gliflozins. CONCLUSIONS: Dapagliflozin use was associated with significant reduction in AF risk as compared to placebo in overall population and patients with diabetes, whereas the use of other gliflozins did not significantly reduce AF occurrence.

Italian Registry in the Setting of Atrial Fibrillation Ablation with Rivaroxaban - IRIS.

BACKGROUND: Catheter ablation (CA) of atrial fibrillation is routinely used to obtain rhythm control. Evidence suggest that catheter ablation should be done during uninterrupted oral anticoagulation. METHODS: Italian Registry in the setting of atrial fibrillation ablation with rivaroxaban (IRIS) is an Italian multicenter, non-interventional, prospective study which enrolled 250 consecutive atrial fibrillation patients eligible for catheter ablation on rivaroxaban. The decision for rivaroxaban management was left to the physician: uninterrupted or shortly interrupted prior to Catheter ablation. Patients received a follow-up visit at 1 month and 12 months after the procedure. RESULTS: The primary outcome, represented by all-cause death and systemic embolism at 1 month and 12 months was characterized by one transient ischemic attack and one myocardial infarction in the first 30 days. Both events happened in patients with shortly interrupted strategy (P=0.147), and both in patients who underwent radiofrequency ablation (P=0.737). In the primary safety outcome represented by major bleeding we did not register any event in the 12-month follow-up. The secondary outcome constituted by minor bleeding registered 1 event, after the first 30 days since CA. CONCLUSIONS: IRIS is the biggest real-life data registry regarding CA ablation on rivaroxaban in Italian setting, proving the safety and efficacy of rivaroxaban.

Pulsed Field Energy in Atrial Fibrillation Ablation: From Physical Principles to Clinical Applications.

Atrial fibrillation, representing the most prevalent sustained cardiac arrhythmia, significantly impacts stroke risk and cardiovascular mortality. Historically managed with antiarrhythmic drugs with limited efficacy, and more recently, catheter ablation, the interventional approach field is still evolving with technological advances. This review highlights pulsed field ablation (PFA), a revolutionary technique gaining prominence in interventional electrophysiology because of its efficacy and safety. PFA employs non-thermal electric fields to create irreversible electroporation, disrupting cell membranes selectively within myocardial tissue, thus preventing the non-selective damage associated with traditional thermal ablation methods like radiofrequency or cryoablation. Clinical studies have consistently shown PFA's ability to achieve pulmonary vein isolation-a cornerstone of AF treatment-rapidly and with minimal complications. Notably, PFA reduces procedure times and has shown a lower incidence of esophageal and phrenic nerve damage, two common concerns with thermal techniques. Emerging from oncological applications, the principles of electroporation provide a unique tissue-selective ablation method that minimizes collateral damage. This review synthesizes findings from foundational animal studies through to recent clinical trials, such as the MANIFEST-PF and ADVENT trials, demonstrating PFA's effectiveness and safety. Future perspectives point towards expanding indications and refinement of techniques that promise to improve AF management outcomes further. PFA represents a paradigm shift in AF ablation, offering a safer, faster, and equally effective alternative to conventional methods. This synthesis of its development and clinical application outlines its potential to become the new standard in AF treatment protocols.

Probability Score to Predict Spontaneous Conversion to Sinus Rhythm in Patients with Symptomatic Atrial Fibrillation When Less Could Be More?

Background: The probability of spontaneous conversion (SCV) to sinus rhythm (SR) in patients presenting to the emergency department (ED) with hemodynamically stable, symptomatic atrial fibrillation (AF) is not well known. Objective: To develop and validate a score to determine the probability of SCV to SR in patients presenting to the ED with hemodynamically stable, symptomatic AF. Methods: This retrospective, observational study enrolled consecutive patients admitted with AF to the ED. Variables associated to SCV during a 6 h "wait-and-see" approach were used to develop and validate a score to determine the probability of SCV to SR in AF patients. The study was divided in two phases: (1) score development and (2) validation of the predictive score. Results: Out of 748 eligible patients, 446 patients were included in the derivation cohort, whereas 302 patients were included in the validation cohort. In the derivation cohort, based on multivariable logistic analysis, a probability score weight was developed including: previous SCV (3 points), AF-related symptom duration < 24 h (5 points), age ≥ 65 years (3 points) and female sex (2 points). The score allowed us to divide patients in three groups based on the probability of SCV to SR during the 6 h observation period. The probability prediction model showed an area under the curve (AUC) of 0.707 and 0.701 in the derivation and validation cohorts, respectively. Conclusions: The proposed score allowed us to predict SCV probability with good accuracy and may help physicians in tailoring AF management in an effective and timely manner.

Mechanical Circulatory Support Systems in the Management of Ventricular Arrhythmias: A Contemporary Overview.

Ventricular tachycardias (VTs) and electrical storms (ES) are life-threatening conditions mostly seen in the setting of structural heart disease (SHD). Traditional management strategies, predominantly centered around pharmacological interventions with antiarrhythmic drugs, have demonstrated limited efficacy in these cases, whereas catheter ablation is related with more favorable outcomes. However, patients with hemodynamically unstable, recurrent VT or ES may present cardiogenic shock (CS) that precludes the procedure, and catheter ablation in patients with SHD portends a multifactorial intrinsic risk of acute hemodynamic decompensation (AHD), that is associated with increased mortality. In this setting, the use of mechanical circulatory support (MCS) systems allow the maintenance of end-organ perfusion and cardiac output, improving coronary flow and myocardial mechanics, and minimizing the effect of cardiac stunning after multiple VT inductions or cardioversion. Although ablation success and VT recurrence are not influenced by hemodynamic support devices, MCS promotes diuresis and reduces the incidence of post-procedural kidney injury. In addition, MCS has a role in post-procedural mortality reduction at long-term follow-up. The current review aims to provide a deep overview of the rationale and modality of MCS in patients with refractory arrhythmias and/or undergoing VT catheter ablation, underlining the importance of patient selection and timing for MCS and summarizing reported clinical experiences in this field.

Inherited Arrhythmias in the Pediatric Population: An Updated Overview.

Pediatric cardiomyopathies (CMs) and electrical diseases constitute a heterogeneous spectrum of disorders distinguished by structural and electrical abnormalities in the heart muscle, attributed to a genetic variant. They rank among the main causes of morbidity and mortality in the pediatric population, with an annual incidence of 1.1-1.5 per 100,000 in children under the age of 18. The most common conditions are dilated cardiomyopathy (DCM) and hypertrophic cardiomyopathy (HCM). Despite great enthusiasm for research in this field, studies in this population are still limited, and the management and treatment often follow adult recommendations, which have significantly more data on treatment benefits. Although adult and pediatric cardiac diseases share similar morphological and clinical manifestations, their outcomes significantly differ. This review summarizes the latest evidence on genetics, clinical characteristics, management, and updated outcomes of primary pediatric CMs and electrical diseases, including DCM, HCM, arrhythmogenic right ventricular cardiomyopathy (ARVC), Brugada syndrome (BrS), catecholaminergic polymorphic ventricular tachycardia (CPVT), long QT syndrome (LQTS), and short QT syndrome (SQTS).

Clinical, procedural and lead outcomes associated with different pacing techniques: a network meta-analysis.

BACKGROUND: His- Purkinje system pacing (HPSP) techniques have been proposed as alternative to biventricular pacing (BVP) and right ventricular pacing (RVP). OBJECTIVE: To compare data regarding clinical, procedural and lead outcomes associated with different pacing techniques. METHODS: An accurate search of online scientific libraries (from inception to May, 12,022) was performed. Thirty-three studies were included in the meta-analysis involving 4386 patients, of whom 1324 receiving RVP, 1032 patients receiving BVP, 1069 patients receiving his-bundle pacing (HBP) and 968 patients receiving left bundle branch pacing (LBBP). RESULTS: LBBP provided a statistically significant increase in LVEF relative to HBP (0.4473 [0.0584; 0.8361] p = 0.0242) and BVP (0.6733 [0.4734; 0.8732] p < 0.0001) in patients with cardiac resynchronization therapy indication. LBBP and HBP significantly decreased QRS duration as compared to BVP, with largest QRS narrowing obtained by LBBP (-0.4951 [-0.9077; -0.0824] p = 0.0187). As compared to LBBP, HBP was associated with a significant increase of pacing threshold (p = 0.0369) and significant reduction of R-wave amplitude over time (p = 0.027). LBBP was associated with significant reduction in RR of hospitalization for HF (HFH) as compared to both BVP (p = 0.0343) and HBP (p = 0.0476), whereas, as compared to RVP, the risk of lead issues was significantly higher with BVP (p = 0.0424) and HBP (p = 0.0298), but not for LBBP (p = 0.425). CONCLUSIONS: As compared to other pacing techniques, LBBP significantly improved LVEF, narrowed QRS duration and reduced HFHs, with steadily lower capture thresholds and higher R-wave amplitude, and without increasing lead issues.

The Feasibility, Effectiveness and Acceptance of Virtual Visits as Compared to In-Person Visits among Clinical Electrophysiology Patients during the COVID-19 Pandemic.

The feasibility and effectiveness of virtual visits (VVs) for cardiac electrophysiology patients are still unknown. We aimed to assess the feasibility and effectiveness of VVs as compared to in-person visits, and to describe patient experience with virtual care in clinical electrophysiology. We prospectively enrolled patients scheduled to receive a clinical electrophysiology evaluation, dividing them in two groups: a VV group and an in-person visit group. Outcomes of interest were: (1) improvement in symptoms after the index visit, (2) disappearance of remote monitoring (RM) alerts at follow-up, (3) necessity of urgent hospitalization and (4) patient satisfaction measured by the Patient Satisfaction Questionnaire-18 (PSQ-18). This study included 162 patients in the VV group and 185 in the in-office visit group. As compared to in-person visits, VVs resulted in a similar reduction in RM alerts (51.5% vs. 43.2%, p-value 0.527) and in symptomatic patient rates (73.6% vs. 56.9%, p-value 0.073) at follow-up, without differences in urgent hospitalization rates (p-value 0.849). Patient satisfaction with VVs was higher than with in-person evaluation (p-value < 0.012). VVs proved to be as feasible and as effective as in-person visits, with high patient satisfaction. A hybrid model of care including VVs and in-person visits may become the new standard of care after the COVID-19 pandemic is over.

Rationale and study design of the Italian Registry in the setting of Atrial Fibrillation Ablation with Rivaroxaban - IRIS.

BACKGROUND: Catheter ablation (CA) of atrial fibrillation (AF) is used routinely to establish rhythm control. There is mounting evidence that CA procedures should be performed during continuous oral anticoagulation and direct oral anticoagulants (DOACs) are considered the first anticoagulation strategy. Few real-life data are now available and even less in the Italian panorama. METHODS: IRIS is an Italian multicenter, non-interventional, prospective study which will be enrolled consecutive AF patients eligible for CA and treated with Rivaroxaban; patients in treatment with Rivaroxaban proceeded directly to CA while Rivaroxaban-naive patients were scheduled for CA after 4 weeks of uninterrupted anticoagulation unless the exclusion of atrial thrombi. Rivaroxaban was uninterrupted or shortly uninterrupted (<24 hours) prior CA, in line with routinely practice of each operator. Patients will be followed on continuous anticoagulation for 1 month after the ablation. The primary efficacy outcome is the cumulative incidence of all-cause death and systemic embolism while the primary safety outcome is the incidence of major bleeding events. The secondary outcomes are represented by non-major bleeding events. All events must be occurred within the first 30 days after the procedure. RESULTS: Two hundred fifty patients are expected to be enrolled and the study is estimated to be completed by the end of 2022. Up to now 56 patients have been enrolled. CONCLUSIONS: This study is the first large Italian prospective study on the management of Rivaroxaban in patients undergoing CA of AF. It aims to depict a comprehensive view of anticoagulation strategy prior CA in several Italian electrophysiology labs.

Incidence and Determinants of Spontaneous Cardioversion of Early Onset Symptomatic Atrial Fibrillation.

Atrial fibrillation (AF) is the most frequent chronic arrhythmia worldwide, and it is associated with significant morbidity and mortality, making it a considerable burden both to patients and the healthcare system. Nowadays, an early attempt to restore sinus rhythm in acute symptomatic AF through electrical or pharmacological cardioversion is the most common approach in the Emergency Department (ED). However, considering the high percentage of spontaneous cardioversion of paroxysmal AF reported by many studies, this approach may not be the ideal choice for all patients. In this manuscript we performed a review of the most relevant studies found in literature with the aim of identifying the main determinants of spontaneous cardioversion, focusing on those easy to detect in the ED. We have found that the most relevant predictors of spontaneous cardioversion are the absence of Heart Failure (HF), a small atrial size, recent-onset AF, rapid Atrial Fibrillatory Rate and the relationship between a previous AF episode and Heart Rate/Blood Pressure. A number of those are utilized, along with other easily determined parameters, in the recently developed "ReSinus" score which predicts the likelihood of AF spontaneous cardioversion. Such identification may help the physician decide whether immediate cardioversion is necessary, or whether to adopt a "watch-and-wait" strategy in the presence of spontaneous cardioversion determinants.

Five Years of Direct Oral Anticoagulants Use in Italy: Adverse Drug Reactions from the Italian National Pharmacovigilance Network.

BACKGROUND: Direct oral anticoagulants (DOACs) are the preferred anticoagulant drugs for the prevention of atrial fibrillation (AF)-related thromboembolic complications and for the treatment and the prevention of recurrences of venous thromboembolism (VTE). The evaluation of self-reported adverse drug reactions (ADRs) available from databases of drug-regulatory agencies such as the Italian Medicines Agency (AIFA) pharmacovigilance database represents a novel aid to guide decision making. OBJECTIVE: To assess the safety profile of DOACs by analyzing ADR rates in the real-world Italian scenario. METHODS: Post-marketing surveillance data recorded by the National Pharmacovigilance Network were retrieved for the time period 2017-2021 from the AIFA online site. The following data were collected for each DOAC: total ADR number, serious ADR number, gastrointestinal (GI) ADR, intracranial hemorrhage events (ICH ADR), and more frequently reported ADR for the study year. The safety profile was expressed by the risk index (RI). RESULTS: Rivaroxaban use was associated with consistent and stable low rates of serious ADR, GI ADR, and ICH ADR across the 5-year study period. Rivaroxaban and apixaban showed the lowest RI for serious ADR and GI ADR, while rivaroxaban use was associated with significantly lower ICH events as compared to apixaban. Dabigatran was related to the highest RIs for every ADR class, in particular GI ADRs. CONCLUSIONS: DOACs presented an acceptable safety profile in the current post-market analysis. However, rivaroxaban and apixaban were associated with more favorable safety profiles as compared to dabigatran, while rivaroxaban provoked statistically significantly fewer ICH events as compared to apixaban.

A mobile app for improving the compliance with remote management of patients with cardiac implantable devices: a multicenter evaluation in clinical practice.

BACKGROUND: The remote device management (RM) is recommended for patients with cardiac implantable electronic devices (CIEDs). RM underutilization is frequently driven by the lack of correct system activation. The MyLATITUDE Patient App (Boston Scientific) has been developed to encourage patient compliance with RM by providing information on communicator setup, troubleshooting, and connection status of the communicator. METHODS: At 14 centers, patients with CIEDs were invited to download and install the App on a mobile device. After 3 months, patients were asked to complete an ad hoc questionnaire to evaluate their experience. RESULTS: The App was proposed to 242 consecutive patients: 81 before RM activation, and 161 during follow-up. The App was successfully installed by 177 (73%) patients. The time required for activation of the communicator and the need for additional support were similar between patients who followed the indications provided by the App and those who underwent standard in-clinic training. During follow-up, notifications of lack of connection were received by 20 (11%) patients and missed transmission by 22 (12%). The median time from notification to resolution was 2 days. After 3 months, 175 (99%) communicators of the 177 patients who installed the App were in "Monitored" status versus 113 (94%) of 120 patients without the App installed (p=0.033). The use of the app made 84% of patients feel reassured. CONCLUSIONS: The App was well accepted by CIED patients and offered support for communicator management and installation. Its use enabled patients to remain connected with greater continuity during follow-up.

Age-related differences and associated mid-term outcomes of subcutaneous implantable cardioverter-defibrillators: A propensity-matched analysis from a multicenter European registry.

BACKGROUND: A few limited case series have shown that the subcutaneous implantable cardioverter-defibrillator (S-ICD) system is safe for teenagers and young adults, but a large-scale analysis currently is lacking. OBJECTIVES: The purpose of this study was to compare mid-term device-associated outcomes in a large real-world cohort of S-ICD patients, stratified by age at implantation. METHODS: Two propensity-matched cohorts of teenagers + young adults (≤30 years old) and adults (>30 years old) were retrieved from the ELISIR Registry. The primary outcome was the comparison of inappropriate shock rate. Complications, freedom from sustained ventricular arrhythmias, and overall and cardiovascular mortality were deemed secondary outcomes. RESULTS: Teenagers + young adults represented 11.0% of the entire cohort. Two propensity-matched groups of 161 patients each were used for the analysis. Median follow-up was 23.1 (13.2-40.5) months. In total, 15.2% patients experienced inappropriate shocks, and 9.3% device-related complications were observed, with no age-related differences in inappropriate shocks (16.1% vs 14.3%; P = .642) and complication rates (9.9% vs 8.7%; P = .701). At univariate analysis, young age was not associated with increased rates of inappropriate shocks (hazard ratio [HR] 1.204 [0.675-2.148]: P = .529). At multivariate analysis, use of the SMART Pass algorithm was associated with a strong reduction in inappropriate shocks (adjusted HR 0.292 [0.161-0.525]; P <.001), whereas arrhythmogenic right ventricular cardiomyopathy (ARVC) was associated with higher rates of inappropriate shocks (adjusted HR 2.380 [1.205-4.697]; P = .012). CONCLUSION: In a large multicenter registry of propensity-matched patients, use of the S-ICD in teenagers/young adults was safe and effective. The rates of inappropriate shocks and complications between cohorts were not significantly different. The only predictor of increased inappropriate shocks was a diagnosis of ARVC.

Impact of COVID-19 Pandemic on Cardiac Electronic Device Management and Role of Remote Monitoring.

During the coronavirus disease 2019 (COVID-19) worldwide pandemic, patients with cardiac implantable electronic device (CIED) refused scheduled follow-up visits because of the risk of infection. In this scenario, different telemedicine strategies have been implemented to ensure continuity of care to CIED patients. Patients can be monitored through dedicated applications, telephone calls, or virtual visits providing easy access to valuable information, such as arrhythmic events, acute decompensation manifestations, and device-related issues, without the need for in-person visits. This review provides a comprehensive description of the many possible applications of telemedicine for CIED patients during the COVID-19 period.

The connubium among diabetes, chronic kidney disease and atrial fibrillation.

The burden of cardiovascular comorbid conditions was significantly higher in patients with atrial fibrillation (AF); most of them are affected by hypertension, chronic kidney disease (CKD) and/or diabetes mellitus (DM). DM represents a well-known risk factor for the development and maintenance of AF; the coexistence of DM and AF is also associated with an increased risk of mortality and stroke. Moreover, DM is currently the main cause of renal impairment and the leading cause of dialysis in the world. The hyperglycemia is responsible for inducing redox imbalance and both systemic and intrarenal inflammation, playing a critical role in the pathogenesis of diabetic kidney disease. Long-term thromboembolic preventive therapy in AF patients with DM and CKD may be more challenging because both DM and CKD have been independently associated with an increased thromboembolic and bleeding risk, which results from the prothrombotic and proinflammatory status. Vitamin K antagonists (VKAs) are characterized by numerous critical issues such as a narrow therapeutic window, increased tissue calcification and an unfavorable risk/benefit ratio with low stroke prevention effect and augmented risk of major bleeding. On the other hand, Direct Oral Anticoagulants (DOACs) are currently contraindicated in dialysis patients even if mounting evidence suggests that they may have a nephroprotective role in AF patients with DM and CKD. Consequently, the choice of anticoagulant therapy in this setting of patient seems to be very challenging. The aim of this review is to investigate the role of DOACs in diabetic patients and its nephroprotective role by reviewing the current literature.

Catheter ablation for papillary muscle arrhythmias: A systematic review.

BACKGROUND: Catheter ablation of papillary muscle ventricular arrhythmias (PM-VAs) has been associated with unsatisfactory results. Features that may affect acute and long-term procedural outcomes are not well established. OBJECTIVE: To systematically review the available data in the literature assessing efficacy and safety of PM-VAs catheter ablation. METHODS: An online search of PubMed, Cochrane Registry, Web of Science, Scopus and EMBASE libraries (from inception to March 1, 2021) was performed, in addition to manual screening. Twenty-one observational noncontrolled case-series were considered eligible for the systematic review, including 536 patients. RESULTS: Postero-medial PM harbored 60.8% of PM-VAs, while antero-lateral PM and right ventricular PMs 34.9% and 4.3% of cases, respectively. The mean acute success rate of the index ablation procedure was 88.1% (95% CI 82.8% to 91.9%, p < .001, I2 0%). After a mean follow-up period of 15.5 ± 17.4 months, pooled long-term arrhythmia-free rate was 69.2%, while the pooled long-term success rate after multiple ablation procedure was 84.9%. Overall, procedure complications occurred in nine patients (1.7%) and no procedure-related deaths were reported. The use of intracardiac echocardiography (ICE) as well as contact force sensing (CFS) and irrigated catheters during ablation was associated with higher rates of arrhythmia-freedom at long-term follow-up. CONCLUSIONS: Catheter ablation is an effective and safe strategy for PM-VAs, with an acute success rate of 88.1%, a long-term success rate of 69.2%, with a relatively low procedural complication rate. The use of ICE, irrigated catheters and catheters with CFS capability was associated with higher rates of arrhythmia-freedom at long-term follow-up.

Subcutaneous implantable cardioverter-defibrillator and defibrillation testing: A propensity-matched pilot study.

BACKGROUND: To date, only a few comparisons between subcutaneous implantable cardioverter-defibrillator (S-ICD) patients undergoing and those not undergoing defibrillation testing (DT) at implantation (DT+ vs DT-) have been reported. OBJECTIVE: The purpose of this study was to compare long-term clinical outcomes of 2 propensity-matched cohorts of DT+ and DT- patients. METHODS: Among consecutive S-ICD patients implanted across 17 centers from January 2015 to October 2020, DT- patients were 1:1 propensity-matched for baseline characteristics with DT+ patients. The primary outcome was a composite of ineffective shocks and cardiovascular mortality. Appropriate and inappropriate shock rates were deemed secondary outcomes. RESULTS: Among 1290 patients, a total of 566 propensity-matched patients (283 DT+; 283 DT-) served as study population. Over median follow-up of 25.3 months, no significant differences in primary outcome event rates were found (10 DT+ vs 14 DT-; P = .404) as well as for ineffective shocks (5 DT- vs 3 DT+; P = .725). At multivariable Cox regression analysis, DT performance was associated with a reduction of neither the primary combined outcome nor ineffective shocks at follow-up. A high PRAETORIAN score was positively associated with both the primary outcome (hazard ratio 3.976; confidence interval 1.339-11.802; P = .013) and ineffective shocks alone at follow-up (hazard ratio 19.030; confidence interval 4.752-76.203; P = .003). CONCLUSION: In 2 cohorts of strictly propensity-matched patients, DT performance was not associated with significant differences in cardiovascular mortality and ineffective shocks. The PRAETORIAN score is capable of correctly identifying a large percentage of patients at risk for ineffective shock conversion in both cohorts.

Electrocardiographic Criteria for Differentiating Left from Right Idiopathic Outflow Tract Ventricular Arrhythmias.

Idiopathic ventricular arrhythmias are ventricular tachycardias or premature ventricular contractions presumably not related to myocardial scar or disorders of ion channels. Of the ventricular arrhythmias (VAs) without underlying structural heart disease, those arising from the ventricular outflow tracts (OTs) are the most common. The right ventricular outflow tract (RVOT) is the most common site of origin for OT-VAs, but these arrhythmias can, less frequently, originate from the left ventricular outflow tract (LVOT). OT-VAs are focal and have characteristic ECG features based on their anatomical origin. Radiofrequency catheter ablation (RFCA) is an effective and safe treatment strategy for OT-VAs. Prediction of the OT-VA origin according to ECG features is an essential part of the preprocedural planning for RFCA procedures. Several ECG criteria have been proposed for differentiating OT site of origin. Unfortunately, the ECG features of RVOT-VAs and LVOT-VAs are similar and could possibly lead to misdiagnosis. The authors review the ECG criteria used in clinical practice to differentiate RVOT-VAs from LVOT-VAs.

Sporadic high pacing and shock impedance on remote monitoring in hybrid implantable cardioverter-defibrillator systems: Clinical impact and management.

BACKGROUND: Sporadic high impedance values without other anomalies detected by remote monitoring of hybrid cardiac implantable electronic device systems have been described recently. The clinical significance and related hazard of this phenomenon are not fully understood. OBJECTIVE: The purpose of this study was to describe the prevalence, management, and outcomes associated with hybrid implantable cardioverter-defibrillator (ICD) systems. METHODS: We collected data on patients with sporadic high lead impedance alert on remote monitoring who had undergone implantation with a hybrid ICD system between January 2015 and December 2019. Pacing thresholds, sensing and impedance values, and temporal pattern of impedance values were collected by remote monitoring, at implantation, and during an in-office visit. RESULTS: Among 92 patients receiving a hybrid ICD, 15 (16.3%) had high impedance alert on remote monitoring (14 Boston Scientific and 1 St. Jude Medical ICD canisters paired with Medtronic or Biotronik DF-1 leads). Four patients had a cardiac resynchronization therapy-defibrillator (CRT-D), 7 a dual-chamber ICD, and 4 a single-chamber ICD. Three patients presented with high atrial lead impedance, 7 high right ventricular lead impedance, 1 high left ventricular impedance, and 2 high shock impedance values. All patients underwent follow-up by remote monitoring. Sporadic high impedance values were not associated with an adverse outcome or need for revision in all but 1 patient, who had continuously increasing pacing thresholds due to lead microfracture. CONCLUSION: In the absence of clear signs of lead fracture or connection issues, sporadic high pacing and shock impedance in hybrid implantable defibrillator systems can be safely managed by close follow-up.