Kowlgi, Gurukripa N.

ABSTRACT Background Transvenous lead removal (TLR) is a Class I indication for patients with cardiac implantable electronic device (CIED) infections. However, disparities in the utilization of TLR have not been fully explored, particularly concerning demographic and socioeconomic factors. Objectives This study aims to examine whether disparities exist among patients hospitalized for CIED infections with respect to the utilization of TLR, focusing on sex, race, and income characteristics. Methods We utilized the 2019 National Inpatient Sample (NIS) to assess patients hospitalized with CIED infections and identify those who underwent TLR. Multiple logistic regression was used to examine risk factors for TLR utilization, including age, sex, race/ethnicity, and socioeconomic characteristics. Results A total of 56 709 patients were hospitalized for CIED infection in the United States in 2019, of which 9867 (17.4%) underwent TLR. On an adjusted analysis, females and Black patients were found to have lower odds of undergoing TLR compared to males and White patients (OR: 0.62; 95% CI: 0.59–0.78; p < 0.01; and OR: 0.47; 95% CI: 0.39–0.57; p < 0.01, respectively). Hispanic patients also had reduced odds of TLR (OR: 0.73; 95% CI: 0.58–0.93; p = 0.01). No significant associations were observed between income or insurance status and the likelihood of receiving TLR after adjustment. Conclusions This study identified significant disparities in the utilization of TLR among patients hospitalized for CIED infections. Female, Black, and Hispanic patients were significantly less likely to receive TLR.

ABSTRACT Background Obesity is an important risk factor associated with atrial fibrillation (AF). The impact of glucagon‐like peptide‐1 receptor agonists (GLP‐1 RAs) on recurrent AF among patients undergoing catheter ablation is not well described. Objective This study aimed to evaluate the effect of GLP‐1 RA on the recurrence of AF among obese patients after catheter ablation. Methods Utilizing the TriNetX research network, we identified patients aged over 18 with obesity (BMI ≥ 30) who underwent AF ablation from January 1, 2015, to December 1, 2022, using Current Procedural Terminology codes. Patients were categorized based on their baseline GLP‐1 RA use. Through propensity‐score matching, each cohort comprised 1558 patients. The primary outcome encompassed a composite of cardioversion, initiation of new antiarrhythmic drug (AAD) therapy, or redo AF ablation. Additional outcomes during the 12‐month follow‐up included AF readmission, heart failure readmissions, readmissions due to ischemic stroke, and mortality, with a separate analysis done for patients with BMI > 40. Results GLP‐1 RA use in patients with obesity undergoing AF ablation was linked to a significantly reduced risk of cardioversion, new AAD therapy, and the need for redo AF ablation (hazard ratio [HR] 0.72 [0.65–0.80]; p < 0.001). At 12 months, individuals on GLP‐1 agonists exhibited a lower likelihood of mortality (HR 0.61 [0.40–0.93]; p < 0.001). Although all other secondary outcomes were lower in the GLP‐1 RA group, there was no significant difference in ischemic stroke between the groups. These results were consistent among patients with BMI > 40, although apart from ischemic stroke, there was no difference in mortality between the two groups. Conclusion The utilization of GLP‐1 RA in individuals with obesity is linked to a decreased likelihood of arrhythmia recurrence following AF ablation, leading to a reduced requirement for cardioversion, AAD therapy, or redo AF ablation.

Abstract Aims Catheter ablation is commonly performed in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) for management of ventricular arrhythmias (VAs). The impact of catheter ablation on cardiac function is unknown. The aim is to assess the impact of catheter ablation for VAs on cardiac function in patients with ARVC. Methods and results This retrospective study included consecutive patients with ARVC who underwent catheter ablation for VAs. Cardiac and valvular functions were assessed on pre- and post-procedure cardiac imaging. The severities of tricuspid regurgitation, pulmonic regurgitation, right ventricular (RV) enlargement, and RV systolic dysfunction was graded as absent (=0), mild (=1), mild-moderate (=2), moderate (=3), moderate-severe (=4), or severe (=5). Thirty-four patients were included. Median age at the time of ablation was 49 [inter-quartile range (IQR), 23] years, and 10 (29%) patients were female. After a median follow-up of 1 (IQR, 0) day, 11 (34%) patients had worsening RV function, and 4 (12%) patients had worsening left ventricular ejection fraction (LVEF) &gt;5%. Five (15%) patients required inotropic support. After a median follow-up of 6.5 (IQR, 6.4) months, 20 (59%) patients had repeat transthoracic echocardiograms. Among patients with worsening RV function post-ablation, one-sixth (17%) had improvement in the RV function at follow-up. In contrast, among patients who had an acute drop in LVEF post-ablation, two-thirds (67%) had improvement at follow-up. Conclusion Right ventricular dysfunction following catheter ablation in patients with ARVC is common, affecting one-third of patients. Patients undergoing catheter ablation of VAs should be counselled on the potential negative impact of ablation on cardiac function.

ABSTRACT Ventricular arrhythmias (VA), including ventricular tachycardia and fibrillation, are critical cardiac conditions that are often managed by catheter ablation among those unresponsive to pharmacologic therapy. The choice of anesthesia and sedation regimens for VA ablations may impact arrhythmia inducibility and hemodynamic stability, which can affect procedural success and complication rates. This systematic review and meta-analysis aimed to compare the efficacy and safety of sedation versus general anesthesia (GA) among patients undergoing VA ablation. The review was prospectively registered on PROSPERO (CRD42023441553). Database searches were conducted across five major databases from inception to March 9, 2024 to identify randomized trials or observational studies including adult patients undergoing ablations for VA. Screening and data extraction were completed in duplicate. Risk-of-bias assessments were conducted using ROBINS-I as all included studies were observational, and the quality of evidence was evaluated using the GRADE framework. Six observational studies (N = 16,435) were included. No significant differences were found between sedation and GA for total procedure time (MD: −14.16 minutes; 95%CI: −38.61 to 10.29 minutes), arrhythmia non-inducibility (RR: 0.73; 95% CI: 0.33–1.58), acute ablation success (RR: 1.06; 95% CI: 0.65–1.71), or procedural complications (RR: 0.72; 95% CI: 0.28–1.85). However, sedation was associated with significantly lower intraprocedural hemodynamic instability (RR: 0.28; 95% CI: 0.12–0.70). These findings indicate that while sedation and GA have comparable outcomes, sedation may be associated with less hemodynamic instability during VA ablation. However, more high-quality studies are needed to confirm these results.

ABSTRACT Background Mitral annular disjunction (MAD) carries an increased risk of complex ventricular arrhythmias, which can lead to sudden cardiac death. Many of these patients undergo implantable cardioverter defibrillator (ICD) implantation, but their ICD outcomes are not known. Objective The aim of this study was to assess the outcomes of ICD implantation and the predictors of appropriate ICD therapies in patients with MAD. Methods The study included patients with MAD who underwent ICD implantation. Clinical, electrocardiographic, cardiac imaging, and device therapy data were collected. Results Forty‐nine patients with MAD and ICD were included. Median age was 49 (21) years, and 29 (59%) were female. 13 (27%) patients underwent ICD implantation for primary prevention and 36 (73%) patients for secondary prevention. Over a median follow‐up of 27.3 (35.3) months, 23 (47%) patients received ICD therapies. 18 (37%) patients had appropriate ICD therapies, and 5 (10%) patients had inappropriate ICD shocks. Median time to first appropriate therapy was 22.3 (63.3) months. In patients with a secondary prevention ICD indication, the rate of appropriate ICD therapies was 44%, while in patients with a primary prevention ICD indication, it was 15%. Among patients with appropriate ICD therapies, the first therapies were delivered for monomorphic ventricular tachycardia (VT) in 7 (39%) patients and polymorphic VT or ventricular fibrillation (VF) in 11 (61%) patients. Patients with appropriate ICD therapies were more likely to have a history of SCA ( p = 0.003) and/or low left ventricular ejection fraction (LVEF) ( p = 0.022) before ICD implantation as compared to patients without appropriate ICD therapies. Conclusions In our cohort of patients with MAD and ICD, appropriate ICD therapies were common. Most appropriate ICD therapies were delivered for polymorphic VT or VF. Larger studies are needed to elucidate the mechanisms of VAs and refine risk stratification in MAD.

BACKGROUND: Power-controlled radiofrequency ablation with irrigated-tip catheters has been the norm for ventricular ablation for almost 2 decades. New catheter technology has recently integrated more accurate tissue temperature sensing enabling temperature-controlled irrigated ablation. We aimed to investigate the in vivo ablation parameters and lesion formation characteristics in ventricular myocardium using a novel temperature-controlled radiofrequency catheter. METHODS: Twenty canines were divided into 3 groups: 4 noninfarcted, acute (phase I); 8 noninfarcted, chronic (phase II); and 8 infarcted, chronic (phase III). Lesions were delivered with a temperature-controlled radiofrequency system utilizing a chemical vapor deposit diamond for efficient thermal diffusivity. In phase I, 17 ablation settings were tested (temperature set points, 50/60/70 °C; ablation duration, 15/30/60/90/120 s; and power limit, 30/50 W). Four and one of these sets of parameters were further tested in phases II and III, respectively. Lesions were assessed by ex vivo contrast-enhanced magnetic resonance imaging and gross pathology 5 weeks after ablation in phases II/III. RESULTS: Across all phases, 111 ablation lesions were delivered. Ablation with the power limit of 50 W, the temperature set point of 60 °C, and the duration of 60 s produced significantly larger and deeper lesions (mean, 569.2 mm 3 ; mean maximal depth, 9.8 mm) compared with 50 W/60 °C/30 s (mean, 340.4 mm 3 ; mean maximal depth, 8.3 mm) and 50 W/50 °C/60 s (mean, 227 mm 3 ; mean maximal depth, 6.9 mm), with P <0.05 for all pairwise comparisons. Ablation of infarcted myocardium in phase III (50 W/60 °C/30 s) resulted in smaller impedance and bipolar electrogram amplitude changes and lesion size compared with ablation in normal myocardium with the same settings. No steam pop, myocardial perforation, or char formation was observed in any of the 111 ablations across all phases. CONCLUSIONS: In vivo radiofrequency ablation in a canine model with a diamond-tip temperature-controlled catheter using a temperature set point of 60 °C and a power limit of 50 W created large lesions without steam pop risk in both normal and infarcted ventricular myocardia.

Background: Patients with adult congenital heart disease (ACHD) form a unique subset of patients with complex ventricular tachycardia (VT). Objective: To evaluate the clinical and procedural characteristics and outcomes of patients with congenital heart disease who present for VT ablation. Methods: A single-center, retrospective study of patients undergoing VT ablation was conducted. The primary composite outcome was recurrent monomorphic VT, and repeat ablation. Results: Out of 508 procedures for ventricular tachycardia ablation, 37 were performed in ACHD patients. These patients were younger compared to the non-ACHD subtype.(Table 1). Out of 26 patients with congenital heart disease, a majority had a diagnosis of tetralogy of Fallot (57.6%) and 69% had 2-3 prior open-heart surgeries, including ventriculotomy (53.8%), ventricular septal defect repair (65.3%), and pulmonary valve replacement (57.6%) (Table2). They had a higher mean LVEF,and lower burden of comorbidities including hypertension, chronic kidney disease, and myocardial infarction compared to their non-ACHD counterparts and had been on fewer antiarrhythmics at baseline. ACHD patients were less likely to require epicardial access, but the requirement for induction meds was higher, and energy delivery times were longer. There were no significant differences in the VT characteristics and mapping techniques between the two groups. There were no significant differences in outcomes including complications, and time to recurrence, and a Kaplan-Meier analysis showed no significant difference in VT free survival when ACHD patients were compared to patients without ACHD (Figure 3). After adjusting for age, sex and comorbidities, ACHD was not a predictor of having VT recurrence or repeat ablation (aHR =1.1 (0.7-1.9), p=0.6) Conclusion: VT ablation in patients with ACHD is safe, and as effective as ablation in non-ACHD patients. Procedure times tend to be longer owing to a more challenging substrate.

Background: PAINESD score was established as a predictor of periprocedural acute hemodynamic instability, long-term mortality and heart failure among patients undergoing catheter ablation for ventricular tachycardia (VT-CA). Objective: To assess the validity of PAINESD score and compare outcomes of high-risk patients undergoing catheter ablation for ventricular tachycardia (VT) with and without mechanical circulatory support (MCS) use during procedure. Methods: We conducted an observational dual-center study of consecutive patients with SHD undergoing VT-CA over a decade (2012-2022). The PAINESD score, based on 7 variables (COPD, age >60 years, general anesthesia, ischemic cardiomyopathy, NYHA class III or IV, ejection fraction <25%, VT storm, and diabetes mellitus), was calculated and categorized into low risk (<10), intermediate risk (10-16), and high risk (>16) as previously reported. Two survival analyses were performed to compare outcomes between different groups: one using all-cause mortality or heart transplant as the event, and another using recurrent or repeat ablation as the event. Multivariable Cox proportional hazards regression models were used to calculate hazard ratios for each PAINESD category and to determine the hazard ratio for the use of MCS among high-risk patients. Results: We found that between 2012 to 2022, 559 ablations were performed on 441 patients. There were 296 (53%), 182 (32.6%) and 81(14.5%) patients in low, medium, and high risk. Using low risk as reference, aHR for medium risk was 2.1 (1.24-3.7; p=0.006) and for high risk was 4.6(2.54-8.3; p <0.001). Among patients with high PAINESD score (n=81), 5 patients (6.2%) required MCS (Intra-arterial balloon pump (IABP)=1, ECMO only=1, ECMO+IABP=1, bypass=2). 4/5 (80%) patients on MCS stayed on them post procedure, except one patient on IABP. In this cohort, there was no difference between patients with and without MCS in primary outcome [aHR= 1.6 (0.48-5.4); p=0.43] and in secondary OUTCOME [1.29 (0.3-5.5; p=0.735)]. Conclusion: PAINESD was a significant predictor of mortality or heart failure, but it did not help in prediction of recurrence of VT, or repeat VT-CA.