Prasitlumkum, Narut

Description of Cases: Case 1: A 72 year old male with atrial fibrillation (AF) and tachy-brady syndrome underwent Micra implantation. On post-procedure day 2, pacing thresholds were unacceptably elevated. A new Micra device was deployed; subsequently, a microsnare was placed through the Micra delivery catheter and the docking button of the old Micra was successfully snared (Figure A). The old Micra was then captured over the delivery catheter and removed from the body. Case 2: A 76 year old male underwent Micra implantation and AV node ablation for AF with persistent tachycardia. One month later, he presented with heart failure and interval decrease in ejection fraction from 66% to 33%. After biventricular leads were implanted, an Agilis catheter was advanced towards the Micra. The docking button was successfully snared with a gooseneck snare (Figure B), and the Micra was extracted with gentle traction. Case 3: A 76 year old male with complete heart block and longstanding persistent AF received a Micra. Nine months later, he presented with heart failure and interval decrease in ejection fraction from 55% to 25%. A defibrillator lead was implanted but no suitable CS branch was identified. The Aveir retrieval catheter was advanced and the Micra docking button was captured with the triloop snare (Figure C). The protective sleeve was advanced over the Micra and it was successfully removed. Subsequently, a left bundle area lead was placed. Discussion: Although uncommon, extraction of the tined leadless pacemaker (Micra) may be indicated at times. As rates of implantation continue to increase, establishing uniform procedures for extraction becomes increasingly important. These three cases highlight unique options for Micra extraction, and the feasibility of each approach. However, a dedicated tool and protocol would be ideal for patient safety and consistency. No complications occurred with the above cases.

Background: Pulsed field ablation (PFA) and high-power short-duration radiofrequency ablation (HPSD) are emerging techniques for treating atrial fibrillation (AF), offering promising results compared to cryoballoon ablation (CBA). This network meta-analysis aims to evaluates the efficacy and safety of PFA, HPSD, and CBA. Method: PubMed, Embase, Cochrane Central Register of Controlled Trials, and EBSCO Information Services were systematically searched for relevant studies until April 2024. The primary outcome is freedom from atrial arrhythmia. A random-effects model was used for data synthesis, and P-scores were employed for outcome ranking. Point estimation (odd ratios) was calculated for comparisons. Results: Fifteen studies were included in our network meta-analysis, involving 5,093 atrial fibrillation patients: 812 (16%), 2,659 (52%), and 1,622 (32%) patients underwent PFA, CBA, and HPSD, respectively. PFA demonstrated the highest efficacy (P-scores 99.3%). Point estimation between PFA and HPSD, and PFA and CBA, were 1.394 (95% CI: 1.047-1.858) and 1.479 (95% CI: 1.134–1.929), respectively. PFA had higher complications compared to HPSD (OR=4.44, 95% CI: 1.405-14.031) and CBA (OR=2.581, 95% CI: 0.992–6.720). HPSD had the shortest fluoroscopic time (P-scores 100%), while CBA had the longest (P-scores 0%). PFA had the shortest procedural time compared to CBA and HPSD with P-scores of 100% 50% and 0%, respectively. Conclusion: PFA showed higher efficacy but higher complication risk than HPSD and CBA. HPSD and CBA demonstrated similar efficacy and safety.

Background: In recent years, catheter ablation has emerged as a sustainable, first-line therapy for the management of ventricular tachycardia (VT). Given the rise of the “obesity paradox” theory in atrial ablation outcomes, we sought to study the effect of BMI on patients undergoing structural VT ablation. Purpose: To assess the outcomes of VT ablation, specifically VT recurrence, in patients with elevated vs. normal BMI. Methods: Clinical characteristics and demographic data were collected for VT patients who underwent ablation at Mayo Clinic Rochester from 2012-2022. Patient BMI was classified as non-obese (<30 kg/m2), obese (30-40 kg/m2), and morbidly obese (≥40 kg/m2). The endpoint was a composite of initial monomorphic VT recurrence and repeat ablation after adjusting for age, sex, and comorbidities. Results: A total of 399 patients underwent 508 ablations. 51.4% of ablations had a BMI <30, 39.2% were between 30-40, and 9.4% were ≥40. There was a greater prevalence of hypertension and type 2 diabetes mellitus in morbidly obese patients (p <0.01). Morbidly obese individuals also had a significantly increased rate of general anesthesia during ablation and long VT cycle lengths. The Kaplan-Meier curve demonstrates no statistically significant differences in time to VT recurrence among the three BMI groups (p = 0.324). Neither morbid-obesity (aHR= 1.20; CI = 0.94-1.56, p = 0.14) nor nonmorbid-obesity (aHR = 0.92; CI = 0.76-1.10, p = 0.4), compared to non-obesity was a significant independent predictor of VT recurrence or repeat ablation on multivariate regression after adjusting for age, sex and comorbidities. Conclusion: There was no significant association between BMI groups and VT recurrence or repeat ablation, and no difference in complications. We did not find the obesity paradox to be relevant for VT ablation in our patient population. Further study would be needed with larger samples to corroborate these findings.

Abstract Background Ventricular tachycardia (VT) is a life-threatening arrhythmia that can complicate structural heart disease. While catheter ablation is effective in treating this condition, the recurrence of VT after the procedure continues to be a concern. Consequently, there is a need for a reliable system to evaluate the likelihood of arrhythmia recurrence following an ablation. Objective To predict recurrence or repeat ablation after a VT catheter ablation procedure using machine learning (ML) models. Methods We conducted a single-center, retrospective study of all patients undergoing catheter ablation for scar-related VT between 2012 and 2022. Data collected included demographics, comorbidities, medications, relevant laboratory abnormalities, electrocardiograms, echocardiograms, detailed procedural characteristics, and outcomes. Python version 3.8.5 for exploratory data analysis (EDA) and visualization. Using six different ML models from the training set (90:10 split), we used 34 variables to predict the primary outcome, including VT recurrence or repeat catheter ablation. The accuracy of these models was compared using ROC curves based on their performance on the test set. Results Out of 508 VT ablation procedures, 261 experienced a recurrence. Support Vector Classifier (SVM) performed the best, having an AUC of 0.73, followed by logistic regression at 0.69 (Figure A). SVM yielded sensitivity, specificity, positive and negative predictive values of 0.73, 0.73, 0.79, and 0.67, respectively. The F1 score was 0.70. Among the factors with the highest feature importance in the model, the most influential variable was the proceduralist’s experience level, followed by QRS width at baseline, LVEF, and patient’s age (Figure B). Conclusion Our model can predict recurrent VT after ablation with reasonable accuracy, outperforming the existing clinical risk scores significantly. Larger training sample sizes will help achieve more robust ML models and improve predictive accuracy further.Figure A: ROC curve depicting the AUROCB. Feature importance graph

AbstractIntroductionDirect oral anticoagulants (DOACs) become the recommended treatment over vitamin K antagonists (VKA) in patients with non‐valvular atrial fibrillation (AF). However, their effectiveness in reducing cognitive impairment and dementia compared to VKA remains unclear.MethodsA systematic literature search was conducted on Ovid MEDLINE, EMBASE, and Cochrane Database. Randomized controlled trials, cohort, or case–control study that assessed incident dementia between AF patients who received DOAC compared to VKA were selected. Relevant study characteristics and the number of incident dementia diagnosis or hazard ratios (HRs) for incident dementia and each dementia subtypes were extracted. Random‐effects model was used to perform meta‐analysis. Standardized mean differences (SMDs) were used to estimate effect sizes for continuous data.ResultsTwelve cohort studies comprising 1 451 069 individuals were included. The incidence of dementia was lower in AF patients prescribed DOACs compared to VKA (HR 0.88, 95% CI 0.83–0.93, I 2 = 61.2%). A lower incident dementia in DOACs group relative to VKA was significantly observed in those less than 75 years of age (< 65 years, HR 0.83 (95% CI 0.72–0.97, I 2 = 0%); 65–74 years, HR 0.86 (95% CI 0.81–0.92, I 2 = 55.4%); and ≥ 75 years, HR 1.07 (95% CI 0.74–1.55, I 2 = 92.5%)) and for the subgroup of patients with vascular dementia (HR 0.91, 95% CI 0.824–0.997, I 2 = 0%).ConclusionsThis meta‐analysis reveals a reduction in incidence of dementia in AF patients prescribed DOACs compared to VKA, particularly in those less than 75 years old and in the vascular dementia subtype.

Abstract Background: The relationships between exercise timing and health outcomes including anthropometric indices, metabolic markers, and sleep health have not been clearly established. To gain better insights, we performed the meta-analysis to determine the effects of morning versus evening exercise on various health outcomes. Methods: We collected studies from MEDLINE, EMBASE, and Cochrane databases from inception to March 2023 to perform a meta-analysis. Exercise is defined as performing activity at least moderate intensity. For the outcomes of interest, the mean differences (MD) were employed using a random-effects model, the generic inverse variance method of DerSimonian and Laird. Results: A total of 716 patients were analyzed from 14 studies including randomized controlled trial and observational studies. We found no significant associations between exercise timing and several health-related parameters. Specifically, the data showed no notable differences in body weight (MD: -0.12 kg [95% CI −0.81 to 0.58]) and BMI (MD: -0.07 kg/m2 [95% CI −0.46 to 0.32]) when comparing morning and evening exercise sessions. Similarly, sleep latency was not significantly affected by exercise timing (MD: -2.24 minutes [95% CI −5.83 to 1.35]). Furthermore, changes in metabolic biomarkers, including LDL (MD: -6.64 mg/dL [95% CI −20.08 to 6.79]) and HDL (MD: 0.09 mg/dL [95% CI 0 to 0.17]), were not significantly associated with the timing of exercise. Conclusion: This meta-analysis found no significant relationship between exercise timing and health outcomes including anthropometric indices, metabolic markers, and sleep health. While considered as hypothesis generating, timing of exercise should equally prune patients’ health outcomes.

Background: Obstructive sleep apnea (OSA) was associated with atrial fibrillation (AF) as well as the recurrence of AF after rhythm control strategy. However, the data on continuous positive airway pressure (CPAP) and recurrent AF after catheter ablation with pulmonary vein isolation (PVI) remain unclear. We conducted this systematic review and meta-analysis to evaluate the effect of CPAP treatment in OSA patients after atrial fibrillation ablation. Methods: We searched MEDLINE and Embase databases from inception to September 2023 to identify studies that assess the effect of CPAP in OSA patients on the recurrence of AF after PVI. Data from each study were combined using the random effects model. Results: Eight studies (one randomized controlled trial and seven cohort studies) with 1487 OSA patients (660 in the CPAP group and 827 in the control group) were included. The use of CPAP in OSA patients was associated with significantly lower AF recurrence after PVI (odds ratio (OR) = 0.36, 95% conference interval (CI) 0.25–0.53, p < 0.001). The results of sensitivity analysis remain the same as the main analysis. Conclusions: Our meta-analysis demonstrated that CPAP treatment was associated with lower rates of AF recurrence after PVI.

AbstractIntroductionAtrioventricular nodal reentrant tachycardia (AVNRT) is the most common supraventricular tachycardia referred for ablation. Periprocedural conduction system damage was a primary concern during AVNRT ablation. This study aimed to assess the incidence of permanent atrioventricular (AV) block and the success rate associated with different types of catheters in slow pathway ablation.MethodA literature search was performed to identify studies that compared various techniques, including types of radiofrequency ablation (irrigated and nonirrigated) and different sizes of catheter tip cryoablation (4, 6, and 8‐mm), in terms of their outcomes related to permanent atrioventricular block and success rate. To assess and rank the treatments for the different outcomes, a random‐effects model of network meta‐analysis, along with p‐scores, was employed.ResultsA total of 27 studies with 5110 patients were included in the analysis. Overall success rates ranged from 89.78% to 100%. Point estimation showed 4‐mm cryoablation exhibited an odds ratio of 0.649 (95%CI: 0.202–2.087) when compared to nonirrigated RFA. Similarly, 6‐mm cryoablation had an odds ratio of 0.944 (95%CI: 0.307–2.905), 8‐mm cryoablation had an odds ratio of 0.848 (95%CI: 0.089–8.107), and irrigated RFA had an odds ratio of 0.424 (95%CI: 0.058–3.121) compared to nonirrigated RFA.ConclusionOur study found no significant difference in the incidence of permanent AV block between the types of catheters. The success rates were consistently high across all groups. These findings emphasize the potential of both RF ablation (irrigated and nonirrigated catheter) and cryoablation as viable options for the treatment of AVNRT, with similar safety and efficacy profile.

The current recommendation for bioprosthetic valve replacement in severe aortic stenosis (AS) is either surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR). We evaluated the performance of a machine learning-based predictive model using existing periprocedural variables for valve replacement modality selection. We analyzed 415 patients in a retrospective longitudinal cohort of adult patients undergoing aortic valve replacement for aortic stenosis. A total of 72 clinical variables including demographic data, patient comorbidities, and preoperative investigation characteristics were collected on each patient. We fit models using LASSO (least absolute shrinkage and selection operator) and decision tree techniques. The accuracy of the prediction on confusion matrix was used to assess model performance. The most predictive independent variable for valve selection by LASSO regression was frailty score. Variables that predict SAVR consisted of low frailty score (value at or below 2) and complex coronary artery diseases (DVD/TVD). Variables that predicted TAVR consisted of high frailty score (at or greater than 6), history of coronary artery bypass surgery (CABG), calcified aorta, and chronic kidney disease (CKD). The LASSO-generated predictive model achieved 98% accuracy on valve replacement modality selection from testing data. The decision tree model consisted of fewer important parameters, namely frailty score, CKD, STS score, age, and history of PCI. The most predictive factor for valve replacement selection was frailty score. The predictive models using different statistical learning methods achieved an excellent concordance predictive accuracy rate of between 93% and 98%.