Feasibility of carbon dioxide insufflation and impact on epicardial approach utilization for ventricular tachycardia ablation in a midvolume referral center.

BACKGROUND: Epicardial access is often crucial for successful ventricular tachycardia (VT) ablation, but it is often burdened by significant procedural risk. Intentional coronary vein exit and intrapericardial CO2 insufflation (EpiCO2) can facilitate subxiphoid pericardial access. OBJECTIVE: This prospective study aimed to assess procedural feasibility, safety, and impact of the introduction of intrapericardial CO2 insufflation for epicardial access in a referral center for VT ablation. METHODS: All consecutive patients treated with epicardial VT ablation between November 2022 and January 2024 with the EpiCO2 technique at Pisa University Hospital were prospectively enrolled and compared in terms of feasibility, efficiency, and safety with a local retrospective cohort of patients treated with subxiphoid dry puncture between July 2018 and October 2022. RESULTS: Twenty-two consecutive patients (90.9% male; mean age, 54.3 years) underwent VT ablation with EpiCO2 during the study period. Epicardial access was achieved in all patients; median time from coronary sinus (CS) cannulation to epicardial access was 33 minutes. Intentional vein exit was successful in all cases, whereas CO2 insufflation was not feasible in 1 patient. There were no major complications and no significant bleeding. Since EpiCO2 introduction, epicardial approach utilization increased from 17.8% to 40% of all VT procedures. Comparison with 20 standard dry approach epicardial ablations showed no significant differences in terms of total procedural duration (322.5 [interquartile range, 296.75-363.75] minutes vs 359 [interquartile range, 323-409] minutes; P = .08). CONCLUSION: In our single-center experience, EpiCO2 was feasible and safe and led to significant increase in procedural volume without affecting total procedural time compared with standard dry puncture.

Transvenous lead extraction: Efficacy and safety of the procedure in female patients.

Background: Existing data on the impact of sex differences on transvenous lead extraction (TLE) outcomes in cardiac device patients are limited. Objective: The purpose of this study was to evaluate the safety and efficacy of mechanical TLE in female patients. Methods: A retrospective evaluation was performed on 3051 TLE patients (group 1: female; group 2: male) from a single tertiary referral center. All individuals received treatment using single sheath mechanical dilation and various venous approaches as required. Results: Our analysis included 3051 patients (group 1: 750; group 2: 2301), with a total of 5515 leads handled with removal. Female patients were younger, had a higher left ventricular ejection fraction, and lower prevalences of coronary artery disease and diabetes mellitus. Infection was more common in male patients, whereas lead malfunction or abandonment were more frequent in female patients. Radiologic success was lower in female patients (95.8% vs 97.5%; P = .003), but there was no significant difference in clinical success between groups (97.2% vs 97.5%; P = .872). However, major complications (1.33% vs 0.60%; P <.001) and procedural mortality (0.4% vs 0.1%; P <.001) were higher in females compared to male patients. After multivariate analysis, female sex emerged as the only predictor of major complications, including deaths (odds ratio 3.96; 95% confidence interval 1.39-11.24). Conclusion: TLE using unpowered simple mechanical sheaths in female patients is safe and effective, but is associated with lower radiologic success and higher complication rates and mortality than in males. This finding underscores the importance of recognizing sex differences in TLE outcomes.

Short and Long-Term Outcomes of Lesion Index-Guided High-Power Short-Duration Approach for Atrial Fibrillation Ablation.

High-power short-duration (HPSD) ablation is an increasingly used ablation strategy for pulmonary vein isolation (PVI) procedures, but Lesion Index (LSI)-guided HPSD radiofrequency (RF) applications have not been described in this clinical setting. We evaluated the procedural efficiency and safety of an LSI-guided HPSD strategy for atrial fibrillation (AF) ablation. Paroxysmal and persistent AF patients scheduled for AF ablation were prospectively enrolled and divided into two groups, according to the ablation power used (≥45 W for the LSI-HP Group and ≤40 W for the LSI-LP group). All patients underwent only PVI LSI-guided ablation (5.5 to 6 anteriorly; 5 to 5.5 superiorly, 4.5 to 5 posteriorly) with a point-by-point strategy and an inter-lesion distance <6 mm. Forty-six patients with AF (25 in the LSI-HP Group vs 21 in the LSI-LP Group)-59% paroxysmal, 78% male, with low-intermediate CHA2DS2-Vasc scores (2 [1-3]), a preserved ejection fraction (65 ± 6%) and a mean left atrial index volume of 39 ± 13 mL/m2 were prospectively enrolled. Baseline clinical characteristics were comparable between groups. PVI was successful in all patients. The RF time (29 (23-37) vs. 49 (41-53) min, p < 0.001), total procedure time (131 (126-145) vs. 155 (139-203) min, p = 0.007) and fluoroscopy time (12 (10-18) vs. 21 (16-26) min, p = 0.001) were significantly lower in the LSI-HP Group. No complications or steam pops were seen in either group. LSI-HP AF ablation significantly improved procedural efficiency-reducing ablation time, total procedural duration, and fluoroscopy use, while maintaining a comparable safety profile to lower-power procedures.

Feasibility and Accuracy of Noninvasive Continuous Arterial Pressure Monitoring during Transcatheter Atrial Fibrillation Ablation.

INTRODUCTION: Transcatheter atrial fibrillation (AF) ablation is still carried out with continuous invasive radial arterial blood pressure (IBP) monitoring in many centers. Continuous noninvasive blood pressure (CNBP) measurement using the volume-clamp method is a noninvasive alternative method used in ICU. No data on CNBP reliability are available in the electrophysiology lab during AF ablation, where rhythm variations are common. BACKGROUND: The objective of the present study was to compare continuous noninvasive arterial pressure measured with the ClearSight device (Edwards Lifesciences, Irvine, CA, USA) with invasive radial artery pressure used as the reference method during AF ablation. METHODS: We prospectively enrolled 55 consecutive patients (age 62 ± 11 years, 80% male) undergoing transcatheter AF ablation (62% paroxysmal, 38% persistent) at our center. Standard of care IBP monitoring via a radial cannula and a contralateral noninvasive finger volume-clamp CNBP measurement device were positioned simultaneously in all patients for the entire procedure. Bland-Altman analysis was used to analyze the agreement between the two techniques. RESULTS: A total of 1219 paired measurements for systolic, diastolic, and mean arterial pressure were obtained in 55 subjects, with a mean (SD) of 22 (9) measurements per patient. The mean bias (SD) was -12.97 (13.89) mmHg for systolic pressure (level of agreement -14.24-40.20; correlation coefficient 0.84), -1.85 (8.52) mmHg for diastolic pressure (level of agreement -18.54-14.84; correlation coefficient 0.77) and 2.31 (8.75) mmHg for mean pressure (level of agreement -14.84-19.46; correlation coefficient 0.85). CONCLUSION: In patients undergoing AF ablation, CNBP monitoring with the ClearSight device showed acceptable agreement with IBP monitoring. Larger studies are needed to confirm the potential clinical implications of continuous noninvasive BP monitoring during AF ablation.

Main roads and land cover shaped the genetic structure of a Mediterranean island wild boar population.

Patterns of genetic differentiation within and among animal populations might vary due to the simple effect of distance or landscape features hindering gene flow. An assessment of how landscape connectivity affects gene flow can help guide management, especially in fragmented landscapes. Our objective was to analyze population genetic structure and landscape genetics of the native wild boar (Sus scrofa meridionalis) population inhabiting the island of Sardinia (Italy), and test for the existence of Isolation-by-Distance (IBD), Isolation-by-Barrier (IBB), and Isolation-by-Resistance (IBR). A total of 393 Sardinian wild boar samples were analyzed using a set of 16 microsatellite loci. Signals of genetic introgression from introduced non-native wild boars or from domestic pigs were revealed by a Bayesian cluster analysis including 250 reference individuals belonging to European wild populations and domestic breeds. After removal of introgressed individuals, genetic structure in the population was investigated by different statistical approaches, supporting a partition into five discrete subpopulations, corresponding to five geographic areas on the island: north-west (NW), central west (CW), south-west (SW), north-central east (NCE), and south-east (SE). To test the IBD, IBB, and IBR hypotheses, we optimized resistance surfaces using genetic algorithms and linear mixed-effects models with a maximum likelihood population effects parameterization. Landscape genetics analyses revealed that genetic discontinuities between subpopulations can be explained by landscape elements, suggesting that main roads, urban settings, and intensively cultivated areas are hampering gene flow (and thus individual movements) within the Sardinian wild boar population. Our results reveal how human-transformed landscapes can affect genetic connectivity even in a large-sized and highly mobile mammal such as the wild boar, and provide crucial information to manage the spread of pathogens, including the African Swine Fever virus, endemic in Sardinia.

Clinical impact of high-density mapping on the acute and long term outcome of atypical atrial flutter ablations.

PURPOSE: We evaluated the clinical impact of the high-density (HD) mapping compared with the standard low-density (LD) ablation catheter mapping technique in the treatment of AFLs. METHODS: We retrospectively evaluated short and long outcomes of patients approached with an HD and a LD electro-anatomical strategy for atypical AFLs. RESULTS: Eighty-seven patients were included. Patients were almost male (60%), relatively old (65 ± 8 years), with a moderate CHA2DS2Vasc score (2.3 ± 1.3), a preserved ejection fraction (58 ± 6), and moderate atrial dilatation (44 ± 7 mm). Baseline clinical characteristics were comparable between groups (p = NS). Among AFLs, 10 (11%) were located in the right and 78 (89%) in the left atrium, including 22 (28%) roof dependent and 37 (47%) mitral dependent (p = NS). Sinus rhythm restoration during ablation was more frequently observed in the HD group (79% vs 56%, p = 0.037), without differences in mapping time, procedural time, and radiological dose (p = NS). Overall AFL/AT/AF recurrence rate at 1, 2, and 3 years was lower in the HD group (14% vs 37% p = 0.02, 14% vs 48% p = 0.002 and 14% vs 50% p < 0.001, respectively) with a time-dependent trend only in the LD group (37% vs 48% vs 50% at 1, 2, and 3 years respectively, p = 0.059). HD mapping (OR 0.17; 95% CI 0.04-0.66) and younger age (OR 1.09; 95% CI 1.01-1.19) resulted independent predictors of overall arrhythmias at follow-up. CONCLUSIONS: Short- and long-term outcomes of atypical AFL ablation were better in the case of HD mapping, which resulted independent predictor of arrhythmia recurrences.

Implantation of cardiac electronic devices in active COVID-19 patients: Results from an international survey.

BACKGROUND: Cardiac implantable electronic device (CIED) implantation rates as well as the clinical and procedural characteristics and outcomes in patients with known active coronavirus disease 2019 (COVID-19) are unknown. OBJECTIVE: The purpose of this study was to gather information regarding CIED procedures during active COVID-19, performed with personal protective equipment, based on an international survey. METHODS: Fifty-three centers from 13 countries across 4 continents provided information on 166 patients with known active COVID-19 who underwent a CIED procedure. RESULTS: The CIED procedure rate in 133,655 hospitalized COVID-19 patients ranged from 0 to 16.2 per 1000 patients (P <.001). Most devices were implanted due to high-degree/complete atrioventricular block (112 [67.5%]) or sick sinus syndrome (31 [18.7%]). Of the 166 patients in the study survey, the 30-day complication rate was 13.9% and the 180-day mortality rate was 9.6%. One patient had a fatal outcome as a direct result of the procedure. Differences in patient and procedural characteristics and outcomes were found between Europe and North America. An older population (76.6 vs 66 years; P <.001) with a nonsignificant higher complication rate (16.5% vs 7.7%; P = .2) was observed in Europe vs North America, whereas higher rates of critically ill patients (33.3% vs 3.3%; P <.001) and mortality (26.9% vs 5%; P = .002) were observed in North America vs Europe. CONCLUSION: CIED procedure rates during known active COVID-19 disease varied greatly, from 0 to 16.2 per 1000 hospitalized COVID-19 patients worldwide. Patients with active COVID-19 infection who underwent CIED implantation had high complication and mortality rates. Operators should take these risks into consideration before proceeding with CIED implantation in active COVID-19 patients.

A standardized approach to empirically define reliable assignment thresholds and appropriate management categories in deeply introgressed populations.

Anthropogenic hybridization is recognized as a major threat to the long-term survival of natural populations. While identifying F1 hybrids might be simple, the detection of older admixed individuals is far from trivial and it is still debated whether they should be targets of management. Examples of anthropogenic hybridization have been described between wolves and domestic dogs, with numerous cases detected in the Italian wolf population. After selecting appropriate wild and domestic reference populations, we used empirical and simulated 39-autosomal microsatellite genotypes, Bayesian assignment and performance analyses to develop a workflow to detect different levels of wolf x dog admixture. Membership proportions to the wild cluster (qiw) and performance indexes identified two q-thresholds which allowed to efficiently classify the analysed genotypes into three assignment classes: pure (with no or negligible domestic ancestry), older admixed (with a marginal domestic ancestry) and recent admixed (with a clearly detectable domestic ancestry) animals. Based on their potential to spread domestic variants, such classes were used to define three corresponding management categories: operational pure, introgressed and operational hybrid individuals. Our multiple-criteria approach can help wildlife managers and decision makers in more efficiently targeting the available resources for the long-term conservation of species threatened by anthropogenic hybridization.

Estimation of pack density in grey wolf (Canis lupus) by applying spatially explicit capture-recapture models to camera trap data supported by genetic monitoring.

BACKGROUND: Density estimation is a key issue in wildlife management but is particularly challenging and labour-intensive for elusive species. Recently developed approaches based on remotely collected data and capture-recapture models, though representing a valid alternative to more traditional methods, have found little application to species with limited morphological variation. We implemented a camera trap capture-recapture study to survey wolf packs in a 560-km2 area of Central Italy. Individual recognition of focal animals (alpha) in the packs was possible by relying on morphological and behavioural traits and was validated by non-invasive genotyping and inter-observer agreement tests. Two types (Bayesian and likelihood-based) of spatially explicit capture-recapture (SCR) models were fitted on wolf pack capture histories, thus obtaining an estimation of pack density in the area. RESULTS: In two sessions of camera trapping surveys (2014 and 2015), we detected a maximum of 12 wolf packs. A Bayesian model implementing a half-normal detection function without a trap-specific response provided the most robust result, corresponding to a density of 1.21 ± 0.27 packs/100 km2 in 2015. Average pack size varied from 3.40 (summer 2014, excluding pups and lone-transient wolves) to 4.17 (late winter-spring 2015, excluding lone-transient wolves). CONCLUSIONS: We applied for the first time a camera-based SCR approach in wolves, providing the first robust estimate of wolf pack density for an area of Italy. We showed that this method is applicable to wolves under the following conditions: i) the existence of sufficient phenotypic/behavioural variation and the recognition of focal individuals (i.e. alpha, verified by non-invasive genotyping); ii) the investigated area is sufficiently large to include a minimum number of packs (ideally 10); iii) a pilot study is carried out to pursue an adequate sampling design and to train operators on individual wolf recognition. We believe that replicating this approach in other areas can allow for an assessment of density variation across the wolf range and would provide a reliable reference parameter for ecological studies.

How much does it cost to look like a pig in a wild boar group?

Hybridization between domestic and wild species is known to widely occur and it is reported to be one of the major causes of the current biodiversity crisis. Despite this, poor attention has been deserved to the behavioural ecology of hybrids, in particular in relation to their social behaviour. We carried out a camera trap study to assess whether phenotypically anomalous colouration in wild boar, i.e. potentially introgressed with domestic pigs, affected the hierarchical structure of wild boar social groups. Chromatically anomalous wild boars (CAWs) were detected in 32 out of 531 wild boar videos. In most videos (75%) CAWs were the latest of the group, independently from their age class and group composition. Aggressions by their wild type fellows were recorded in 31.25% videos; by contrast, no aggression among wild type individuals was observed. The lack of camouflage may expose CAWs, and thus their group, to a higher predation risk, compared to wild type groups. This individual loss of local adaptation may increase predation risk by the wolf or detection by hunters, being maladaptive for the whole social group.