Selection of candidates for cardiac resynchronization therapy and implantation management: an Italian survey promoted by the Italian Association of Arrhythmology and Cardiac Pacing.

BACKGROUND: Cardiac resynchronization therapy (CRT) represents an effective heart failure treatment, associated with reduction in mortality and heart failure hospitalizations. This Italian survey aimed to address relevant CRT issues. METHODS: An online survey was administered to AIAC members. RESULTS: One hundred and five electrophysiologists participated, with a median of 40 (23-70) CRT implantations/year (33% in high-volume centres). Forty-five percent of respondents (especially working in high-volume centres) reported an increase in CRT implantations in the last 2 years, in 16% a decrease, and in 38% CRT remained stable. Seventy-five percent of respondents implanted CRT only in patients with European Heart Rhythm Association (EHRA) class I indications. All operators collected ECG and echocardiography before implantation. Eighty-five percent of respondents selected coronary sinus target vein empirically, whereas 10% used mechanical and/or electrical delay techniques. Physicians working in high-volume centres reported a lower failure rate compared with others (16 vs. 34%; P = 0.03). If the coronary sinus lead could not be positioned in the target branch, 80% placed it in another vein, whereas 16% opted for a surgical approach or for conduction system pacing (CSP). Eighty percent accomplished CRT optimization in all patients, 17% only in nonresponders. Regarding anticoagulation, high agreement with EHRA guidelines emerged. CONCLUSION: CRT represents a valid therapeutic option in heart failure treatment. Nowadays, CRT implantations remain stable and are mainly performed in patients with class I indications. ECG remains the preferred tool for patient selection, whereas imaging is increasingly used to determine the left pacing target area. In most patients, the left ventricular lead can be successfully positioned in the target vein, but in some cases, the result can be unsatisfactory; however, the decision to explore alternative resynchronization approaches is rarely pursued.

Contact-force local impedance algorithm to guide effective pulmonary vein isolation in AF patients: 1-year outcome from an international multicenter clinical setting.

BACKGROUND: The combination of highly localized impedance (LI) and contact force (CF) may improve tissue characterization and lesion prediction during radiofrequency (RF) pulmonary vein isolation (PVI) in patients with atrial fibrillation (AF). OBJECTIVE: We report the outcomes of our acute and long-term clinical evaluation of CF-LI-guided PVI in consecutive AF ablation cases from an international multicenter clinical setting. METHODS: Three hundred twenty-four consecutive patients from 20 European centers undergoing RF catheter ablation with the Stablepoint™ catheter were enrolled in the CHARISMA registry. Of these, 275 had a minimum follow-up of 1 year and were included in the primary analysis. RESULTS: The mean procedure duration was 115 ± 47 min, and the mean fluoroscopy time was 9.9 ± 6 min. At the end of the procedures, all PVs had been successfully isolated in all study patients. Minor complications were reported in 12 patients (4.4%). At 1 year, 36 (13.1%) patients had had an AF recurrence, and freedom from antiarrhythmic drugs and AF recurrence was achieved in 228 (82.9%) patients. The recurrence rate was higher in patients with persistent AF (21/116, 18.1%) than in those with paroxysmal AF (15/159, 9.4%; p = 0.0459). On multivariate logistic analysis adjusted for baseline confounders, only time > 6 months from first diagnosis of AF to ablation (HR = 2.93, 95%CI 1.03 to 8.36, p = 0.0459) was independently associated with recurrences. CONCLUSION: An ablation strategy for PVI guided by CF-LI technology proved safe and effective and resulted in a low recurrence rate of AF over 1-year follow-up, irrespective of the underlying AF type. CLINICAL TRIAL REGISTRATION: Catheter Ablation of Arrhythmias with a High-Density Mapping System in Real-World Practice. (CHARISMA). URL: http://clinicaltrials.gov/ Identifier: NCT03793998.

Role of the vessel morphology on the lenticulostriate arteries hemodynamics during atrial fibrillation: A CFD-based multivariate regression analysis.

BACKGROUND AND OBJECTIVE: Atrial fibrillation (AF) is the most common cardiac arrhythmia, inducing accelerated and irregular beating. Beside well-known disabling symptoms - such as palpitations, reduced exercise tolerance, and chest discomfort - there is growing evidence that an alteration of deep cerebral hemodynamics due to AF increases the risk of vascular dementia and cognitive impairment, even in the absence of clinical strokes. The alteration of deep cerebral circulation in AF represents one of the least investigated among the possible mechanisms. Lenticulostriate arteries (LSAs) are small perforating arteries mainly departing from the middle cerebral artery (MCA) and susceptible to small vessel disease, which is one of the mechanisms of subcortical vascular dementia development. The purpose of this study is to investigate the impact of different LSAs morphologies on the cerebral hemodynamics during AF. METHODS: By combining a computational fluid dynamics (CFD) analysis of LSAs with 7T high-resolution magnetic resonance imaging (MRI), we performed different CFD-based multivariate regression analyses to detect which geometrical and morphological vessel features mostly affect AF hemodynamics in terms of wall shear stress. We exploited 17 cerebral 7T-MRI derived LSA vascular geometries extracted from 10 subjects and internal carotid artery data from validated 0D cardiovascular-cerebral modeling as inflow conditions. RESULTS: Our results revealed that few geometrical variables - namely the size of the MCA and the bifurcation angles between MCA and LSA - are able to satisfactorily predict the AF impact. In particular, the present study indicates that LSA morphologies exhibiting markedly obtuse LSA-MCA inlet angles and small MCA size downstream of the LSA-MCA bifurcation may be more prone to vascular damage induced by AF. CONCLUSIONS: The present MRI-based computational study has been able for the first time to: (i) investigate the net impact of LSAs vascular morphologies on cerebral hemodynamics during AF events; (ii) detect which combination of morphological features worsens the hemodynamic response in the presence of AF. Awaiting necessary clinical confirmation, our analysis suggests that the local hemodynamics of LSAs is affected by their geometrical features and some LSA morphologies undergo greater hemodynamic alterations in the presence of AF.

Pulsed field vs very high-power short-duration radiofrequency ablation for atrial fibrillation: Results of a multicenter, real-world experience.

BACKGROUND: Pulsed field ablation (PFA) and very high-power short-duration (vHPSD) radiofrequency ablation are the most recently introduced technologies for atrial fibrillation (AF) ablation. The procedural performance, safety, and effectiveness of PFA vs vHPSD are currently unknown. OBJECTIVE: The study aimed to compare PFA with vHPSD for the treatment of paroxysmal or persistent AF. METHODS: We conducted an observational, multicenter study enrolling 534 consecutive patients (63 ± 9 years; 36% female) with paroxysmal (n = 368 [69%]) or persistent (n = 166 [31%]) AF undergoing ablation by either PFA (Farawave; n = 192) or vHPSD (90 W/4 seconds; QDOT Micro; n = 342) between 2020 and 2023. Atrial tachyarrhythmia recurrence after a 1-month blanking period was the primary efficacy end point and was assessed both overall and in propensity score-matched patients. The primary safety end point was a composite of procedure-related complications. RESULTS: Successful pulmonary vein isolation was achieved in all patients, with shorter procedure duration (PFA,70 minutes; vHPSD, 100 minutes; P < .001) but longer fluoroscopy time (PFA, 15 minutes; vHPSD, 7 minutes; P < .001) in the PFA group. PFA was associated with more frequent use of general anesthesia (P < .001). Primary safety outcome events occurred in 19 patients (3.5%), with similar prevalence in both groups (PFA, 4%; vHPSD, 3%; P = .745). After a median follow-up of 12 (9-12) months, survival free from recurrent atrial tachyarrhythmia was similar between the PFA and vHPSD groups, both overall (12-month estimate: PFA, 75%; vHPSD, 76%; log-rank P = .73) and in propensity score-matched patients (n = 342; 12-month estimate: PFA, 75%; vHPSD, 77%; log-rank P = .980). CONCLUSION: In a large, multicenter experience, PFA was associated with more common use of general anesthesia, shorter procedural times, and longer fluoroscopy exposure compared with vHPSD ablation, with both techniques displaying superimposable safety and efficacy.

Severe Periprocedural Complications After Ablation for Atrial Fibrillation: An International Collaborative Individual Patient Data Registry.

BACKGROUND: Catheter ablation for atrial fibrillation (AF) including pulmonary vein isolation and possibly further substrate ablation is the most common electrophysiological procedure. Severe complications are uncommon, but their detailed assessment in a large worldwide cohort is lacking. OBJECTIVES: The aim of this study was to determine the incidence of periprocedural severe complications and to provide a detailed characterization of the diagnostic evaluation and management of these complications in patients undergoing AF ablation. METHODS: Individual patient data were collected from 23 centers worldwide. Limited data were collected for all patients who underwent catheter ablation, and an expanded series of data points were collected for patients who experienced severe complications during periprocedural follow-up. Incidence, predictors, patient characteristics, management details, and overall outcomes of patients who experienced ablation-related complications were investigated. RESULTS: Data were collected from 23 participating centers at which 33,879 procedures were performed (median age 63 years, 30% women, 71% radiofrequency ablations). The incidence of severe complications (n = 271) was low (tamponade 6.8‰, stroke 0.97‰, cardiac arrest 0.41‰, esophageal fistula 0.21‰, and death 0.21‰). Age, female sex, a dilated left atrium, procedure duration, and the use of radiofrequency energy were independently associated with the composite endpoint of all severe complications. Among patients experiencing tamponade, 13% required cardiac surgery. Ninety-three percent of patients with complications were discharged directly home after a median length of stay of 5 days (Q1-Q3: 3-7 days). CONCLUSIONS: This large worldwide collaborative study highlighted that tamponade, stroke, cardiac arrest, esophageal fistula, and death are rare after AF ablation. Older age, female sex, procedure duration, a dilated left atrium, and the use of radiofrequency energy were associated with severe complications in this multinational cohort. One in 8 patients with tamponade required cardiac surgery.

Epicardial Atrial Fat at Cardiac Magnetic Resonance Imaging and AF Recurrence after Transcatheter Ablation.

The relationship between epicardial adipose tissue (EAT) and atrial fibrillation (AF) has gained interest in recent years. The previous literature on the topic presents great heterogeneity, focusing especially on computed tomography imaging. The aim of the present study is to determine whether an increased volume of left atrial (LA) EAT evaluated at routine pre-procedural cardiac magnetic resonance imaging (MRI) relates to AF recurrences after catheter ablation. A total of 50 patients undergoing AF cryoballoon ablation and pre-procedural cardiac MRI allowing quantification of LA EAT were enrolled. In one patient, the segmentation of LA EAT could not be achieved. After a median follow-up of 16.0 months, AF recurrences occurred in 17 patients (34%). The absolute volume of EAT was not different in patients with and without AF recurrences (10.35 mL vs. 10.29 mL; p-value = 0.963), whereas the volume of EAT indexed on the LA volume (EATi) was lower, albeit non-statistically significant, in patients free from arrhythmias (12.77% vs. 14.06%; p-value = 0.467). The receiver operating characteristic curve testing the ability of LA EATi to predict AF recurrence after catheter ablation showed sub-optimal performance (AUC: 0.588). The finest identified cut-off of LA EATi was 10.65%, achieving a sensitivity of 0.5, a specificity of 0.82, a positive predictive value of 0.59 and a negative predictive value of 0.76. Patients with values of LA EATi lower than 10.65% showed greater survival, free from arrhythmias, than patients with values above this cut-off (84% vs. 48%; p-value = 0.04). In conclusion, EAT volume indexed on the LA volume evaluated at cardiac MRI emerges as a possible independent predictor of arrhythmia recurrence after AF cryoballoon ablation. Nevertheless, prospective studies are needed to confirm this finding and eventually sustain routine EAT evaluation in the management of patients undergoing AF catheter ablation.

A Quantitative Assessment of Cerebral Hemodynamic Perturbations Associated with Long R-R Intervals in Atrial Fibrillation: A Pilot-Case-Based Experience.

Background and Objectives: Atrial fibrillation (AF) results in systemic hemodynamic perturbations which impact cerebral circulation, possibly contributing to the development of dementia. However, evidence documenting effects in cerebral perfusion is scarce. The aim of this study is to provide a quantitative characterization of the magnitude and time course of the cerebral hemodynamic response to the short hypotensive events associated with long R-R intervals, as detected by near-infrared spectroscopy (NIRS). Materials and Methods: Cerebral NIRS signals and arterial blood pressure were continuously recorded along with an electrocardiogram in twelve patients with AF undergoing elective electrical cardioversion (ECV). The top 0.5-2.5% longest R-R intervals during AF were identified in each patient and used as triggers to carry out the triggered averaging of hemodynamic signals. The average curves were then characterized in terms of the latency, magnitude, and duration of the observed effects, and the possible occurrence of an overshoot was also investigated. Results: The triggered averages revealed that long R-R intervals produced a significant drop in diastolic blood pressure (-13.7 ± 6.1 mmHg) associated with an immediate drop in cerebral blood volume (THI: -0.92 ± 0.46%, lasting 1.9 ± 0.8 s), followed by a longer-lasting decrease in cerebral oxygenation (TOI: -0.79 ± 0.37%, lasting 5.2 ± 0.9 s, p < 0.01). The recovery of the TOI was generally followed by an overshoot (+1.06 ± 0.12%). These effects were progressively attenuated in response to R-R intervals of a shorter duration. Conclusions: Long R-R intervals cause a detectable and consistent cerebral hemodynamic response which concerns both cerebral blood volume and oxygenation and outlasts the duration of the systemic perturbation. These effects are compatible with the activation of dynamic autoregulatory mechanisms in response to the hypotensive stimulus.

Convolutional neural network (CNN)-enabled electrocardiogram (ECG) analysis: a comparison between standard twelve-lead and single-lead setups.

Background: Artificial intelligence (AI) has shown promise in the early detection of various cardiac conditions from a standard 12-lead electrocardiogram (ECG). However, the ability of AI to identify abnormalities from single-lead recordings across a range of pathological conditions remains to be systematically investigated. This study aims to assess the performance of a convolutional neural network (CNN) using a single-lead (D1) rather than a standard 12-lead setup for accurate identification of ECG abnormalities. Methods: We designed and trained a lightweight CNN to identify 20 different cardiac abnormalities on ECGs, using data from the PTB-XL dataset. With a relatively simple architecture, the network was designed to accommodate different combinations of leads as input (<100,000 learnable parameters). We compared various lead setups such as the standard 12-lead, D1 alone, and D1 paired with an additional lead. Results: This has been corrected to "The CNN based on single-lead ECG (D1) achieved satisfactory performance compared to the standard 12-lead framework (average percentage AUC difference: −8.7%). Notably, for certain diagnostic classes, there was no difference in the diagnostic AUC between the single-lead and the standard 12-lead setups. When a second lead was detected in the CNN in addition to D1, the AUC gap was further reduced to an average percentage difference of -2.8% compared with that of the standard 12-lead setup. Conclusions: A relatively lightweight CNN can predict different classes of cardiac abnormalities from D1 alone and the standard 12-lead ECG. Considering the growing availability of wearable devices capable of recording a D1-like single-lead ECG, we discuss how our findings contribute to the foundation of a large-scale screening of cardiac abnormalities.

Continuous stellate ganglion block for ventricular arrhythmias: case series, systematic review, and differences from thoracic epidural anaesthesia.

AIMS: Percutaneous stellate ganglion block (PSGB) through single-bolus injection and thoracic epidural anaesthesia (TEA) have been proposed for the acute management of refractory ventricular arrhythmias (VAs). However, data on continuous PSGB (C-PSGB) are scant. The aim of this study is to report our dual-centre experience with C-PSGB and to perform a systematic review on C-PSGB and TEA. METHODS AND RESULTS: Consecutive patients receiving C-PSGB at two centres were enrolled. The systematic literature review follows the latest Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. Our case series (26 patients, 88% male, 60 ± 16 years, all with advanced structural heart disease, left ventricular ejection fraction 23 ± 11%, 32 C-PSGBs performed, with a median duration of 3 days) shows that C-PSGB is feasible and safe and leads to complete VAs suppression in 59% and to overall clinical benefit in 94% of cases. Overall, 61 patients received 68 C-PSGBs and 22 TEA, with complete VA suppression in 63% of C-PSGBs (61% of patients). Most TEA procedures (55%) were performed on intubated patients, as opposed to 28% of C-PSGBs (P = 0.02); 63% of cases were on full anticoagulation at C-PSGB, none at TEA (P < 0.001). Ropivacaine and lidocaine were the most used drugs for C-PSGB, and the available data support a starting dose of 12 and 100 mg/h, respectively. No major complications occurred, yet TEA discontinuation rate due to side effects was higher than C-PSGB (18 vs. 1%, P = 0.01). CONCLUSION: Continuous PSGB seems feasible, safe, and effective for the acute management of refractory VAs. The antiarrhythmic effect may be accomplished with less concerns for concomitant anticoagulation compared with TEA and with a lower side-effect related discontinuation rate.

INFLA-score: A new diagnostic paradigm to identify pericarditis.

BACKGROUND: Diagnosis of pericarditis may be challenging because not all patients meet the conventional criteria. An overlooked diagnosis implies a longer course of symptoms and an increased risk of recurrences. C-reactive protein (CRP), widely used as an inflammation marker, has some limitations. This study aimed to assess the usefulness and prognostic value of INFLA-score, a validated index assessing low-grade inflammation, in the definite diagnosis of pericarditis. METHODS: Patients with suspected pericarditis were included. The INFLA-score was computed based on white blood cells and platelet count, neutrophil-to-lymphocyte ratio, and CRP, ranging from -16 to +16. An INFLA-score > 0 was considered positive for the presence of pericardial inflammation. The primary end point was the association of INFLA-score with diagnosis of pericarditis according to conventional criteria. The recurrence of pericarditis at 6 months was the secondary end point. RESULTS: A total of 202 patients were included, aged 47 ± 17 years, and 57% were females. Among 72 (36%) patients with a diagnosis of pericarditis, an INFLA-score > 0 was observed in 86% (vs. 36%, p < 0.001), abnormal CRP in 42% (vs. 10%, p < 0.001), pericardial effusion in 44% (vs. 19%, p < 0.001), abnormal electrocardiogram in 56% (vs. 24%, p < 0.001), and rubs in 5% (vs. 0.1%, p = 0.072). INFLA-score > 0 had the strongest predictive value for the diagnosis of pericarditis (hazard ratio 8.48, 95% confidence interval [CI] 3.39-21.21), with 86% sensitivity and 64% specificity, as opposed to CRP (hazard ratio 1.72, non-significant 95% CI 0.69-4.29). Recurrent pericarditis at 6 months was more frequent in patients with a positive INFLA-score (37% vs. 8%, p < 0.001, rate ratio 4.15, 95% CI 2.81-6.12). In patients with normal CRP, INFLA-score-confirmed ongoing inflammation in 78% of the cases. Compared with the conventional criteria, the INFLA-score had the highest accuracy (area under the curve = 0.82). Different cutoffs were valuable to rule out (INFLA-score > 0, sensitivity 86%, and negative likelihood ratio 0.22) or rule in (INFLA-score ≥ 10, specificity 97%, and positive likelihood ratio 13) the diagnosis. CONCLUSIONS: The INFLA-score is a useful diagnostic tool to assess the probability of pericarditis, with a strong prognostic value for further recurrences, outperforming CRP.

MRI pattern characterization of cerebral cardioembolic lesions following atrial fibrillation ablation.

Background: Recognizing etiology is essential for treatment and secondary prevention of cerebral ischemic events. A magnetic resonance imaging (MRI) pattern suggestive of an embolic etiology has been described but, to date, there are no uniformly accepted criteria. Aim: The purpose of the study is to describe MRI features of ischemic cerebral lesions occurring after transcatheter ablation of atrial fibrillation (AF). Methods: A systematic review and meta-analysis of studies performing brain imaging investigations before and after AF transcatheter ablation was performed. The incidence of cerebral ischemic lesions after AF transcatheter ablation was the primary endpoint. The co-primary endpoints were the prevalence of the different neuroimaging features regarding the embolic cerebral ischemic lesions. Results: A total of 25 studies, encompassing 3,304 patients, were included in the final analysis. The incidence of ischemic cerebral lesions following AF transcatheter ablation was 17.2% [95% confidence interval (CI) 12.2%-23.8%], of which a minimal fraction was symptomatic [0.60% (95% CI 0.09%-3.9%)]. Only 1.6% of the lesions (95% CI 0.9%-3.0%) had a diameter >10 mm, and in 20.5% of the cases the lesions were multiple (95% CI 17.1%-24.4%). Brain lesions were equally distributed across the two hemispheres and the different lobes; cortical location was more frequent [64.0% (95% CI 42.9%-80.8%)] while the middle cerebral artery territory was the most involved 37.0% (95% CI 27.3-48.0). Conclusions: The prevailing MRI pattern comprises a predominance of small (<10 mm) cortical lesions, more prevalent in the territory of the middle cerebral artery.

Role of atrial high-rate episodes in stratifying thromboembolic risk: a multiple cut-off diagnostic meta-analysis.

Aims: Despite the high prevalence rate of atrial high-rate episodes (AHREs) detected using cardiac implantable electronic devices (CIEDs), clinical guidelines and consensus documents have disagreed on a universal AHRE definition and a temporal cut-off related to subsequent thromboembolic events. This diagnostic test accuracy meta-analysis aims to derive the optimal temporal threshold of clinically significant AHREs from the available literature. Methods: The PubMed/MEDLINE and EMBASE databases were screened for studies on CIED patients reporting the incidence of thromboembolic events related to at least one AHRE temporal cut-off. A total of 23 studies were included: 19 considering the longest single AHRE and four the AHRE burden, respectively. A random-effect diagnostic test accuracy meta-analysis with multiple cut-offs was performed. Two analyses were performed according to the AHRE temporal cut-off subtype (longest episode vs. cumulative burden). Results: The analysis on the longest single AHRE indicated 0.07 min as the optimal duration to differentiate AHRE associated or not with thromboembolic events [sensitivity 65.4% (95% CI 48.8%-79.0%), specificity 52.7% (95% CI 46.0%-59.4%), and area under the summary receiver operating characteristic curve (AUC-SROC): 0.62]. The analysis on AHRE burden indicated 1.4 min as the optimal cut-off [sensitivity 58.2% (95% CI 25.6%-85.0%), specificity 57.5% (95% CI 42.0%-71.7%), and AUC-SROC 0.60]. A sensitivity analysis excluding patients with a history of atrial fibrillation and including high-quality studies only yielded similar results. Conclusion: The presence of AHRE, rather than a specific duration, relates to an increased, albeit low, thromboembolic risk in CIED patients. Any AHRE should constitute an additional element in patient-specific thromboembolic risk assessment.

Evaluation of Pulmonary Vein Fibrosis Following Cryoballoon Ablation of Atrial Fibrillation: A Semi-Automatic MRI Analysis.

Current guidelines recommend the use of cardiac magnetic resonance imaging (MRI) for the management of atrial fibrillation (AF). However, the widespread use of cardiac MRI in clinical practice is difficult to achieve. The aim of the present study is to assess whether cardiac MRI can be adopted to identify ablation-induced fibrosis, and its relationship with AF recurrences. Fifty patients undergoing AF cryoballoon ablation were prospectively enrolled. Cardiac MRI was performed before and 30 days after the index ablation. Commercially available software and a specifically designed image processing workflow were used to quantify left atrium (LA) fibroses. Thirty-six patients were finally included in the analysis; twenty-eight were analyzed with the dedicated workflow. Acute electrical isolation was achieved in 98% of the treated pulmonary veins (PVs). After a median follow-up of 16 months, AF recurrences occurred in 12 patients (33%). In both analyses, no differences were found between the subgroups of patients with and without recurrence in the variation of either LA fibrosis or fibrosis at the ostium of the PV, before and after ablation. The ability to predict arrhythmic recurrences evaluated via the ROC curve of the variations in both LA fibrosis (AUC 0.566) and PV fibrosis (AUC 0.600) was low. Cardiac MRI holds the potential to provide clinically significant information on LA disease and AF progression; however, LA fibrosis cannot be easily identified, either by currently available commercial programs or custom tools.

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.

Practical guidance to reduce radiation exposure in electrophysiology applying ultra low-dose protocols: a European Heart Rhythm Association review.

Interventional electrophysiology offers a great variety of treatment options to patients suffering from symptomatic cardiac arrhythmia. Catheter ablation of supraventricular and ventricular tachycardia has globally evolved a cornerstone in modern arrhythmia management. Complex interventional electrophysiological procedures engaging multiple ablation tools have been developed over the past decades. Fluoroscopy enabled interventional electrophysiologist throughout the years to gain profound knowledge on intracardiac anatomy and catheter movement inside the cardiac cavities and hence develop specific ablation approaches. However, the application of X-ray technologies imposes serious health risks to patients and operators. To reduce the use of fluoroscopy during interventional electrophysiological procedures to the possibly lowest degree and to establish an optimal protection of patients and operators in cases of fluoroscopy is the main goal of modern radiation management. The present manuscript gives an overview of possible strategies of fluoroscopy reduction and specific radiation protection strategies.

Prognosis of CRT-treated and CRT-untreated unselected population with LBBB in Stockholm County.

AIMS: Left bundle branch block (LBBB) might be the first finding of cardiovascular diseases but also the prerequisite for cardiac resynchronization therapy (CRT) in heart failure (HF) with reduced ejection fraction (HFrEF). The prognosis for patients with LBBB and the implications of CRT in an unselected real-world setting are the focus of our study. METHODS AND RESULTS: A central electrocardiogram (ECG) database and national registers have been screened to identify patients with LBBB. Predictors of HF and the use of CRT were identified with Cox models. The hazard ratios (HRs) of death, cardiovascular death (CVD), and HF hospitalization (HFH) were estimated according to CRT use. Of 5359 patients with LBBB and QRS > 150 ms, median age 76 years, 36% were female. At the time of index ECG, 41% had a previous history of HF and 27% developed HF. Among 1053 patients with a class I indication for CRT, only 60% received CRT with a median delay of 137 days, and it was associated with a lower risk of death [HR: 0.45, 95% confidence interval (CI): 0.36-0.57], CVD (HR: 0.47, 95% CI: 0.35-0.63), and HFH (HR: 0.56, 95% CI: 0.48-0.66). The age of over 75 years and the diagnosis of dementia and chronic obstructive pulmonary disease were predictors of CRT non-use, while having a pacing/defibrillator device independently predicted CRT use. CONCLUSION: In an unselected LBBB population, CRT is underused but of great value for HF patients. Therefore, it is crucial to find ways of better implementing and understanding CRT utilization and characteristics that influence the management of our patients.