Dhawan, Rahul

AbstractBackgroundLeft bundle branch block (LBBB) induced cardiomyopathy is an increasingly recognized disease entity. However, no clinical testing has been shown to be able to predict such an occurrence.Case reportA 70‐year‐old male with a prior history of LBBB with preserved ejection fraction (EF) and no other known cardiovascular conditions presented with presyncope, high‐grade AV block, and heart failure with reduced EF (36%). His coronary angiogram was negative for any obstructive disease. No other known etiologies for cardiomyopathy were identified. Artificial intelligence‐enabled ECGs performed 6 years prior to clinical presentation consistently predicted a high probability (up to 91%) of low EF. The patient successfully underwent left bundle branch area (LBBA) pacing with correction of the underlying LBBB. Subsequent AI ECGs showed a large drop in the probability of low EF immediately after LBBA pacing to 47% and then to 3% 2 months post procedure. His heart failure symptoms markedly improved and EF normalized to 54% at the same time.ConclusionsArtificial intelligence‐enabled ECGS may help identify patients who are at risk of developing LBBB‐induced cardiomyopathy and predict the response to LBBA pacing.

Background: Catheter ablation is an effective tool to reduce ventricular tachycardia (VT) burden. There is a lack of robust data studying the characteristics and outcomes of VT ablation in patients with ischemic (ICM) versus non-ischemic cardiomyopathy (NICM). Aims: The aim of this study was to assess the impact of ICM vs NICM on outcomes of VT ablation. Methods: A single-center, retrospective study of patients undergoing catheter ablation for VT was conducted. Results: A total of 168 patients, undergoing 200 VT ablation procedures, were included in this study. NICM group (112 procedures) was compared to ICM group (88 procedures). Patients in the ICM group were older (66.6 ± 13.4 vs 58.9 ± 14.4 years) and had higher rates of prior myocardial infarction (65.9% vs 3.6) and coronary artery bypass graft surgery (40.9% vs 1.8%). Overall, ICM group had more comorbidities like hypertension (80.7% vs 52.7%), diabetes mellitus (23.9% vs 12.5%), chronic kidney disease (45.5% vs 35.7%), stroke (17% vs 7.1%), and lower left ventricular ejection fraction (36.8 ± 13.2% vs 43.1 ± 14.7%). The ICM group had lower incidence of prior cardiac valvular surgery (9.1% vs 29.5%). The inducibility of VT (93% vs 93.5%; p= 1.0) and the number of different VT morphologies induced during the case (1.9 ± 1.5 vs 2.3 ± 2.5; p=0.19) was similar between the two groups. There was no acute mortality in either group. There was a non-significant trend towards greater VT recurrence in the NICM group (43.2% vs 33.3%, p= 0.19). However, patients with NICM had a lower VT-free survival as determined by Kaplan-Meier analysis (p=0.05) [Figure]. Long term mortality was higher in ICM group when compared to NICM group (18.2% vs 8.9%, p<0.01). Conclusion: Patients undergoing VT ablation in the NICM group when compared to the ICM group were noted to be younger, had fewer comorbidities, and lower long-term mortality. However, they had significantly less VT-free survival, likely owing to more challenging substrate responsible for VT.

Abstract Background Catheter ablation of ventricular tachycardia (VT) may be performed under general anesthesia (GA) or monitored anesthesia care (MAC). There is a paucity of data studying these two sedation strategies with respect to intraprocedural characteristics, and outcomes of VT ablation. Purpose The purpose of this study was to assess the effects of anesthesia techniques on VT inducibility and outcomes. Methods A single-center, retrospective study of patients undergoing catheter ablation for scar-related VT, from 2016-2022, was conducted. Data collected included demographics, comorbidities, medications, relevant laboratory abnormalities, electrocardiograms, echocardiograms, detailed procedural characteristics, and outcomes. Results One hundred sixty-eight patients who underwent a total of 200 VT ablation procedures were included. The patients undergoing GA had a greater burden of comorbidities including congestive heart failure (77.2% vs. 60.9%), hypertension (66.9% vs. 60.0%), atrial arrhythmias (50.7% vs. 43.8%), diabetes mellitus (21.3% vs. 9.4%), chronic kidney disease (44.1% vs. 31.3%), prior stroke (11.8% vs. 10.9%), myocardial infarction (31.6% vs. 29.7%), pre-existing implantable cardioverter-defibrillator (86.8% vs. 71.9%) and had a higher median number of antiarrhythmic drugs at baseline (2 vs. 1) [Figure 1]. There was a greater percentage of patients with non-ischemic cardiomyopathy (58.1% vs. 51.6%) in the GA cohort. The mean left ventricular ejection fraction was not different among the two groups (39.3 ± 13.9 vs. 42.5 ± 15.3). The GA group had more hemodynamic instability at baseline (p &lt; 0.01), and during VT induction (p &lt; 0.01). There was no significant difference in the number of VT induced, or tachycardia cycle length, in each group. Despite higher radiofrequency energy delivery time in the GA group as compared to the MAC group, the GA group had higher VT inducibility post-procedure and were more likely to be discharged on antiarrhythmic drugs. Even though the recurrence of VT was higher in the GA group compared to the MAC group (41.9% vs. 31.3%), the VT-free survival curves were not significantly different by Kaplan-Meier analysis (p=0.19) [Figure 2]. In a multivariate regression analysis, the sedation strategy was not an independent predictor of VT recurrence (p=NS). However, baseline hemodynamic instability was an independent predictor of VT recurrence after accounting for all intraprocedural characteristics (p=0.008). Conclusion Patients undergoing VT ablation under GA have more comorbidities and tend to be on more antiarrhythmic drugs. The GA group had more hemodynamic instability during the procedure and had greater overall VT recurrence, however, not significant in a time-based analysis. The greater overall recurrence in the GA group could be because they represent a sicker population, or the hemodynamics during the procedure preclude adequate ablation of the VT circuit elements.Figure 1Figure 2

Abstract Background Catheter ablation of ventricular tachycardia (VT) has emerged as the mainstay of management for these sick patients. There is a lack of long-term data studying the characteristics and outcomes of VT ablation in females and the comparison with males. Purpose The purpose of the study was to assess the impact of sex on outcomes of catheter ablation for ventricular tachycardia. Methods A single-center retrospective study of 200 procedures in 168 patients undergoing catheter ablation for scar-related VT under GA or MAC sedation was conducted. Data collected included demographics, comorbidities, medications, relevant laboratory abnormalities, electrocardiograms, structural data including echocardiograms and cardiac magnetic resonance imaging, detailed procedural characteristics, and outcomes. Results Females undergoing VT ablation were younger (49.4 ± 15.6 vs. 65.5 ± 12.2 years) [Figure 1]. Females had a lower burden of comorbidities, including congestive heart failure (30.0 % vs. 82.5%), hypertension (27.5% vs. 74.4%), atrial arrhythmias (20.0% vs. 55.6%), chronic kidney disease (25.0% vs. 43.8%), prior myocardial infarction (15.0% & 35.0%), and coronary artery bypass graft surgery (0.0% & 23.8%). Females were on fewer antiarrhythmic drugs at baseline. During the procedure, males had a greater likelihood of undergoing general anesthesia (72.5% vs. 50.0%) and associated hemodynamic instability at baseline (30.0% vs. 12.5%). It was more likely for VT to be induced in males, and females required more induction medications. There was no difference in complication rates between males and females. A greater proportion of males were discharged and maintained on antiarrhythmic drugs after the procedure. There was no significant difference in VT recurrence or long-term mortality. Using Kaplan-Meier analysis, no difference was seen in long-term VT-free survival by sex (p=0.20) [Figure 2]. In a multivariate regression model, female sex had no bearing on the VT-free survival. Conclusion Females undergoing catheter ablation for VT are younger and have fewer comorbidities. They tend to be on fewer antiarrhythmic drugs at baseline, and after ablation. Interestingly, despite a healthier baseline profile, females do not experience less VT recurrence or mortality compared to males. Further study would be needed to investigate this association.Figure 1Figure 2

Abstract Background Catheter ablation has emerged as the first-line therapy for management of ventricular tachycardia (VT) over the last decade. There is a reluctance for older patients to be referred for catheter ablation with concerns for complications and poor outcomes. Purpose The purpose of the study was to assess the safety and outcomes of catheter ablation for VT in patients more than 74 years of age in comparison to younger patients. Methods A single-center retrospective study of 200 procedures in 168 patients undergoing catheter ablation for scar-related VT was conducted. Data collected included demographics, comorbidities, medications, relevant laboratory abnormalities, electrocardiograms, Holter, device electrograms, structural data including echocardiograms and cardiac magnetic resonance imaging, detailed procedural characteristics, and outcomes. Results The mean age in the older cohort was 77.7 ± 3.7 years compared to 57.6 ± 13.1 years in the younger group (p &lt; 0.01) [Figure 1]. The geriatric patients had more males (93.6% vs. 75.8%) and had greater proportion of comorbidities including congestive heart failure (89.4% vs. 66.7%), hypertension (91.5% & 56.9%), atrial arrhythmias (66.0% vs. 43.1%), chronic kidney disease (68.1% vs. 31.4%), prior myocardial infarction (53.2% vs. 24.2%), and stroke (21.3% vs. 8.5%). The older patients were on more antiarrhythmic drugs at baseline. During the procedure, the number of cases with VT induction and hemodynamic stability was similar in older and younger groups. In cases where VT was induced, the older patients had a greater number of VTs induced (2.7 ± 3.0 vs. 1.9 ± 1.8), with slower cycle lengths (454.9 ± 122.6 vs. 379.3 ± 108.1 milliseconds). There was no difference noted in the procedural complications between the two groups. Older patients were more likely to be discharged on antiarrhythmic medications (87.2% vs. 71.2%) and had higher long-term mortality (29.8% vs. 7.8%). The older group was less likely to have a repeat ablation procedure (8.5% vs 24.2%). There was no difference in long-term VT-free survival rates among the two groups [Figure 2]. Conclusion Patients more than 74 years of age undergoing catheter ablation for structural VT have a greater comorbidity burden but demonstrate similar procedural complications and VT-free survival rates, when compared to the younger cohort.Figure 1Figure 2