Journal of Cardiovascular Electrophysiology最新文献

Background: The formation of transmural lesions is necessary for the ablation of persistent atrial fibrillation (prAF). Ablation index (AI) and generator impedance drop (ID) predict lesion size but their correlation with long-term outcomes in prAF is not known. Furthermore, we proposed a new parameter, efficacy ratio (ER) calculated as ID/AI, to gain indirect insight into the role of factors affecting ID but not considered by AI.

Methods: We included ablations performed during the DECAAF II trial if they had uploaded lesion-by-lesion summary data and were performed with radiofrequency catheters on the CARTO system. Average patient-level parameters were calculated from all generated Vizitags.

Results: A total of 427 ablations met inclusion criteria and 166 utilized AI. Analyzed as continuous variables, ID and ER predicted long-term arrhythmia-free survival but not AI. The ideal cut-off for ID was ID ≥ 10.4 ohms and had a C-index of 0.55. It predicted reduced risk of arrhythmia: hazard ratio 0.56 [0.36-0.88], p = .013 (arrhythmia-free survival of 67% vs. 52%). Similarly, an ER of 1.7 ohms/100AI had a C-index of 0.58 and predicted reduced arrhythmia recurrence: HR 0.39 [0.22-0.69], p = .001. ER < 1.7 ohms/100AI was related to just 32% arrhythmia-free survival. ER improved prognostication as compared to ID alone and identified a subset of low ID patients with even worse outcomes.

Conclusion: Average ID was predictive of improved outcomes following ablation of prAF. The ratio of ID/AI (ER) was postulated as a measure to summarize the overall impact of factors not considered in the AI formula and provided improved prognostication.

Introduction: Pulsed electric field (PEF) has emerged as a promising energy source for catheter ablation of atrial fibrillation (AF). However, data regarding the in-vivo effect of PEF energy on erythrocytes during AF ablation procedures are scarce. This study aimed to quantify the impact of PEF energy on erythrocyte damage during AF ablation by assessing specific hemolytic biomarkers.

Methods: A total of 60 patients (age: 68 years, males: 72%, serum creatinine: 91 µmol/L) with AF underwent catheter ablation of AF using PEF energy delivered by a multipolar pentaspline Farawave catheter (Farapulse, Boston Scientific, Inc.). Ablation beyond pulmonary vein isolation was performed at the operator's discretion. Peripheral venous blood was sampled for assessing the plasma levels of free hemoglobin (fHb), direct (conjugated) bilirubin, lactate dehydrogenase (LDH), and creatinine before, immediately after the ablation, and on the next day.

Results: Following the PEF ablation with duration of [median (interquartile range)] 75 (58, 95) min, with 74 (52, 92) applications and PVI only in 27% of patients, fHb, LDH, and direct bilirubin significantly increased, from 40 (18, 65) to 493 (327, 848) mg/L, from 3.1 (2.6, 3.6) to 6.8 (5.0, 7.9) µkat/L, and from 12 (9, 17) to 28 (16, 44) µmol/L, respectively (all p < .0001). A strong linear correlation was found between the peak fHb and the number of PEF applications (R = 0.81, p < .001). The major hemolysis (defined as fHb >500 mg/L) was predicted by the number of PEF applications with the corresponding area under the receiver operating characteristic curve of 0.934. The optimum cut-off value of >74 PEF applications predicted the major hemolysis with 89% sensitivity and 87% specificity.

Conclusion: Catheter ablation of AF using PEF energy delivered from a pentaspline catheter is associated with significant intravascular hemolysis. More than 74 PEF applications frequently resulted in major hemolysis. However, the critical amount of PEF energy that may cause kidney injury in susceptible patients remains to be investigated.

Introduction: The Medtronic Micra VR and Abbott AVEIR VR are the leadless pacemakers (LPM) currently available in the United States (US). Micra VR employs fixation tines and the AVEIR VR uses an active fixation helix. Micra VR requires fixation before electrical measurements are obtained, while R-waves may be mapped by AVEIR VR without fixation. Little comparative data is available for these LPMs. Accordingly, we compared the incidences of procedure-related major adverse clinical events (MACE) and device problems in the US for Micra VR and AVEIR VR during 2022-2024.

Methods: We searched the FDA's Manufacturer and User Facility Device Experience (MAUDE) database for US reports of MACE and device problems that were filed from April 2022 to December 2023 for AVEIR VR, and from June 2022 to April 2024 for Micra VR. Totals for US-registered LPM implants were obtained from the manufacturers' product performance reports.

Results: During the study period, 5990 AVEIR VR and 10 940 Micra VR implants were registered in the US. We found 305 MAUDE reports for AVEIR VR (5.1%), versus 541 MAUDE reports for Micra VR (4.9%) (p = .702). The incidence of MACE was 0.72% (43/5990) for AVEIR VR versus 0.59% (65/10 940) for Micra VR, (p = .387). The incidences of procedure-related death, cardiac perforation. cardiac arrest, emergency pericardial drainage or reparative surgery were similar for both LPMs (p > .05). Micra VR had more unacceptable thresholds requiring LPM replacement compared to AVEIR VR (95;0.9% vs. 24;0.4%; p = .001). AVEIR VR had a statistically higher incidence of device dislodgement during (32) and after (21) implant compared to Micra VR (53 (0.9%) vs. 46 (0.4%), p < .001).

Conclusions: Micra VR and AVEIR VR have similar procedural safety profiles, including the incidences of death and perforation. However, device problems differed significantly, possibly related to their design differences. Compared to Micra VR, AVEIR VR appears to have an advantageous threshold measurement capability but is more prone to device dislodgement.

Introduction: Various catheter designs are appearing for Pulsed Field Ablation (PFA). It is unclear if they differ in terms of safety and efficiency. PFA studies have reported hemolysis, kidney injury, high troponin, among other side effects.

Methods: Using a CT-derived computer model, we compared catheter designs using two metrics: (1) efficiency: power delivered to an atrial wall target, expressed as a percent of total generator power; and (2) safety: electric current to achieve 90% transmurality (since more energy causes more collateral effects), as well as the corresponding electrode current density (ECD), a heat and bubble metric. The following catheter designs were compared: penta-spline basket, Nitinol spheres (focal 9 mm and large 1-shot), circular, balloon, and flex-circuit. Target was a 6 × 47 mm circumferential segment of atrial wall at LPV antrum. Transmurality was defined as percent of target having >600 volts per centimeter (V/cm) electric field needed for electroporation.

Results: Efficiency was 0.9, 1.4, 2.7, 5.9, 10, and 12% for the large 1-shot and 9 mm Nitinol spheres, penta-spline, circular, flex spline, and balloon catheters, respectively. Regarding safety, currents for 90% transmurality were 70, 39,36,12.5, 5.3, and 4 Amps for the same respective catheters, with less being safer. ECD was 124, 25, 74, 83, 41, and 31 A/cm², respectively.

Conclusion: Computer models demonstrated a remarkable range in efficiency among catheters studied. Those having less atrial blood exposure had the highest efficiencies, with factors of up to 13X more efficiency compared to exposed ones. Higher efficiency designs have less collateral current and are safer. Confirmatory in-vivo studies are required.

Introduction: To evaluate the cost and efficiency of suture-mediated percutaneous closure (SMC) compared to manual compression (MC) after atrial fibrillation (AF) ablation. SMC has been demonstrated to be efficacious in reducing hemostasis and bedrest times after AF ablation. To date, randomized data comparing the direct and indirect cost between the two techniques have not been described.

Methods: We conducted a 1:1 randomized trial comparing SMC to MC following AF ablation. The primary endpoints have been previously published. However, secondary endpoints pertinent to indirect cost including complication rates, hospital utilization (i.e., delays in discharge, additional patient encounters, nursing utilization), pain, patient reported outcomes, as well as the direct costs of care associated with AF ablation were collected. We also performed secondary analysis of the primary endpoint to evaluate for a learning curve, and subgroups analysis comparing efficacy across different numbers of access sites and compared to those in the MC group with a figure-of-eight suture (Fo8), that could potentially have impacted the relative efficiency of the procedure.

Results: A total of 107 patients were randomized and included: 53 in the SMC group and 54 in MC. A learning curve was observed in the SMC group between the first and second half of the study group (p = 0.037), with no such difference in the MC group. After accounting for the number of access sites, time to hemostasis remained shorter in the SMC Group (p = 0.002). Compared to those in the Fo8 arm (n = 37), the time to hemostasis remained shorter in the SMC group (p = 0.001). Among those planned for same-day discharge, there were more delays in the MC group (31.5% vs. 11.3%, p = 0.0144). Rates of major and minor complications were similar between SMC and MC groups at discharge (p = 0.243) and 30 days (p = 1.00), as were nursing utilization, self-reported pain, and overall patient reported outcomes. The overall cost of care related to the procedure was similar between the MC and SMC groups ($56 533.65 [$45 699.47, $66 987.64] vs. $57 050.44 [$47 251.40, $66 426.34], p = 0.601).

Conclusion: SMC has been shown to decrease time to hemostasis and ambulation and facilitate earlier same-day discharge after AF ablation without an increase in direct or indirect costs.

Introduction: Atrial fibrillation (Afib) is a prevalent chronic arrhythmia associated with severe complications, including stroke, heart failure, and increased mortality. This review explores the use of smartwatches for Afib detection, addressing the limitations of current monitoring methods and emphasizing the potential of wearable technology in revolutionizing healthcare.

Results/observation: Current Afib detection methods, such as electrocardiography, have limitations in sensitivity and specificity. Smartwatches with advanced sensors offer continuous monitoring, improving the chances of detecting asymptomatic and paroxysmal Afib. The review meticulously examines major clinical trials studying Afib detection using smartwatches, including the landmark Apple Heart Study and ongoing trials such as the Heart Watch, Heartline, and Fitbit Heart Study. Detailed summaries of participant numbers, smartwatch devices used, and key findings are presented. It also comments on the cost-effectiveness and scalability of smartwatch-based screening, highlighting the potential to reduce healthcare costs and improve patient outcomes.

Conclusion/relevance: The integration of wearable technology into healthcare can lead to earlier diagnosis, improved patient engagement, and enhanced cardiac health monitoring. Despite ethical considerations and disparities, the potential benefits outweigh the challenges. This review calls for increased awareness, collaboration with insurance companies, and ongoing research efforts to optimize smartwatch accuracy and encourage widespread adoption of Afib detection. With insights from major trials, this review serves as a comprehensive reference for healthcare professionals and policymakers, guiding future strategies in the early diagnosis and management of atrial fibrillation.