Pothineni, Naga Venkata K.

Background: Bilateral cardiac sympathetic denervation (BCSD) has shown promise in treating patients with nonischemic cardiomyopathy (NICM) suffering from refractory multifocal premature ventricular contractions (PVCs) and ventricular tachycardia (VT). Despite its growing use, the effectiveness of BCSD across different NICM etiologies has not been extensively studied. Research Question: How effective is BCSD across a variety of NICM etiologies? Goals: To evaluate the effectiveness of BCSD on left ventricular ejection fraction (LVEF) and PVC burden in patients with NICM. Methods: We conducted a subset analysis on a previous retrospective, observational study of NICM patients who underwent BCSD. Eight NICM etiologies were assessed. Results: 43 NICM patients underwent BCSD (mean age 52.3±14.7 years; 30% females). Overall, LVEF significantly improved (38.7±7.9% to 46.2±9.6%, p <0.001), and PVC burden (PVCb) significantly decreased (23.7±9.9% to 1.3±1%, p <0.001). A similar phenomenon was seen in idiopathic/dilated cardiomyopathy (CM) (LVEF: +8.7%, p <0.001; PVCb: -20.6%, p <0.001), post-viral CM (LVEF: +4.8%, p =0.2; PVCb: -24.2%, p <0.001), familial CM (LVEF: +10%; PVCb: +23.3%), giant cell CM (LVEF: +10%; PVCb: + 30.5%), and arrhythmogenic right ventricular CM (LVEF: +12.5%, p=0.09; PVCb -30.6%, p =0.001). Catecholaminergic polymorphic VT had a non-significant increase in LVEF (+5%, p=0.5) but a significant decrease in PVCb (-21.8%, p=0.02), whereas sarcoidosis had the opposite effect with significant increase in LVEF (LVEF: +13.4%, p=0.3) but non-significant decrease in PVCb (-16.1%, p=0.02). Lastly, hypertrophic CM remained unchanged in LVEF (30%) but PVCb decreased (-8%). Conclusion: BCSD demonstrates efficacy in improving LVEF and reducing PVCb across almost all NICM with refractory VT. However, a case-by-case evaluation is still needed for its use.

Introduction: Cardiac arrhythmias are common in continuous flow left ventricular assist device (LVAD) recipients. The impact of axial vs. intrapericardial centrifugal LVAD pumps on arrhythmia incidence and associated clinical outcomes is unclear. Hypothesis: This multicenter study evaluated the impact of LVAD type (axial vs. centrifugal) on incidence of atrial and ventricular arrhythmias, ICD shocks and mortality in LVAD patients. Methods: Analysis was done on 536 patients who underwent LVAD implantation at 5 US centers from 2008 to 2016. The groups were divided based on their LVAD type (axial - HeartMate II [HMII, n=433] vs. centrifugal - HeartWare (HW, n=103). Baseline characteristics as well as incidence of post-LVAD atrial arrhythmias (PL-AA), ventricular arrhythmias (PL-VA) and ICD shocks were analyzed in these groups. Multivariable Cox Regression analysis was used to identify predictors of survival. Results: Of 536 patients, 433 had HMII axial LVAD and 103 had HW centrifugal VAD implant. At baseline, HMII group had more males, higher proportion of CRT-D and higher prevalence of AA (Table 1A). Left ventricular dimensions were similar between groups. During a median follow-up of 537 days of LVAD support, incidence of PL-VA and ICD shocks were significantly higher in the HM2 group compared to HW group whereas incidence of PL-AA was not significantly different (Table 1A). In multivariable Cox Regression analysis, LVAD indication was the only variable that predicted survival (Table 1B). Type of LVAD (axial vs. centrifugal) was not associated with survival (HMII vs. HW - HR 1.04, P=0.48). Conclusions: In this multi-center continuous flow LVAD cohort, axial HM2 VAD patients had a higher incidence of PL-VA and ICD shocks. Type of LVAD (axial vs. centrifugal) was not associated with survival.

Abstract Background It is unclear if the location of implantation of the leadless pacemaker (LP) makes a difference in the incidence of pacing‐induced cardiomyopathy (PICM). Aim The aim of this study was to compare the incidence of PICM based on the location of implantation of LP. Methods A total of 358 consecutive patients [women: 171 (48%), mean age: 73 ± 15 years] with left ventricular ejection fraction (EF) > 50%, who received an LP (Micra) between January 2017 and June 2022, formed the study cohort. Micra‐AV and Micra‐VR were implanted in 122 (34%) and 236 (66%) patients, respectively. Fluoroscopically, the location of implantation of LP in the interventricular septum (IS) was divided into two equal halves (apex/apical septum [AS] and mid/high septum [HS]). During follow‐up, PICM was defined as an EF drop of ≥10%. Results LP was implanted in 109 (34%) and 249 (66%) patients at AS and HS locations, respectively. During a mean 18 ± 8 months follow‐up, 28 patients (7.8%) developed PICM. Among the 249 patients with HS placement of LP, 10 (4%) developed PICM, whereas among the 109 patients with AS placement of LP, 18 (16.5%) developed PICM ( p = .002). AS location was associated with a higher risk of PICM compared to HS locations (adjusted hazard ratio: 4.42, p < .001). Conclusion AS location of LP was associated with a higher risk of PICM compared to HS placement. Larger randomized studies are needed to confirm our findings.

Introduction: The availability, national scope and perceived unbiased nature of administrative claims data makes it an attractive choice by health care policy makers for evaluating quality and outcomes. We calculated Ventricular tachycardia (VT) ablation complication rates from national administrative data and compared them with data from randomized trials and prospective studies. Methods: A PUBMED database search was done to identify existing studies of VT ablation. Studies were divided into clinical (randomized controlled trials (RCTs) and prospective studies). Pooled rates of vascular, cardiac, neurological complications and procedure related mortality were computed and compared to reported complication rates from administrative database studies Results: We identified two administrative database studies of VT ablation that included a total of 14,352 procedures and 18 clinical studies with a total of 1,705 procedure. Overall complication rate in administrative studies was higher than in clinical studies (9.39% vs. 7.97%). Rates of cardiac/pericardial (4.47% vs. 2.29%) and vascular access complications (6.9% vs. 3.0%) were higher in real world studies. Neurological complications (1.17% vs. 0.45%) and procedure related mortality (1.53% vs. 1.29%) were higher in clinical studies. Among clinical studies, RCTs had the lowest reported complication rate. Conclusion: Despite substantial improvement, “real-world” complication rates from administrative data remain higher than those reported in RCTs. The discrepancy may be attributable to differences in operator skills, selection bias and variation in data quality. Use of large databases provides an important analytical resource as we embark on improving national health care efficacy and safety in the current challenging environment.

AbstractIntroductionCatheter ablation (CA) has emerged as the preferred modality of treatment for many cardiac arrhythmias. Anatomical sites of ablation are often located in close proximity to coronary arteries. However, the incidence of CA‐related coronary injury has not been well studied. We sought to systematically evaluate all cases of CA‐related coronary injuries.Methods and ResultsA PubMed search was conducted from inception until May 1, 2017 using the keywords “coronary artery” and “ablation.” We identified 2817 published articles of which 43 articles met our inclusion criteria representing 61 cases of coronary artery injury attributed to CA procedures from 1992 to 2017. Posteroseptal accessory pathway ablation was associated with the highest incidence of coronary injury (35.6% of cases), followed by cavotricuspid isthmus‐dependent flutter (19.3%). The right coronary artery was the site of injury in over two‐thirds of all reported cases. Coronary injury was detected intraprocedurally in about half of the cases (43.1%), whereas it was a delayed presentation in the other half. Coronary intervention was performed in a third of all cases (32.7%). There were a total of three deaths attributed to coronary artery injury.ConclusionsMost (91.8%) coronary injuries are a result of anatomic proximity to the site of ablation. Awareness of the relation between coronary artery course and anatomical site of ablation could prevent myocardial damage and improve procedural safety.

AbstractBackground: The utilization of cardiac resynchronization therapy defibrillator (CRT‐D) has increased significantly, since its initial approval for use in selected patients with heart failure. Limited data exist as for current trends in implant‐related in‐hospital complications and cost utilization. The aim of our study was to examine in‐hospital complication rates associated with CRT‐D and their trends over the last decade.Methods and Results: Using the Nationwide Inpatient Sample, we estimated 378 248 CRT‐D procedures from 2003 to 2012. We investigated common complications, including mechanical, cardiovascular, pericardial complications (hemopericardium, cardiac tamponade, or pericardiocentesis), pneumothorax, stroke, vascular complications (consisting of hemorrhage/hematoma, incidents requiring surgical repair, and accidental arterial puncture), and in‐hospital deaths described with CRT‐D, defining them by the validated International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis code. Mechanical complications (5.9%) were the commonest, followed by cardiovascular (3.6%), respiratory failure (2.4%), and pneumothorax (1.5%). Age (≥65 years), female gender (OR, 95% CI; P value) (1.08, 1.03‐1.13; 0.001), and the Charlson score ≥3 (1.52, 1.45‐1.60; <0.001) were significantly associated with increased mortality/complications.Conclusions: The overall complication rate in patients undergoing CRT‐D has been increasing in the last decade. Age (≥65), female sex, and the Charlson score ≥3 were associated with higher complications. In patients who underwent CRT‐D implantation, postoperative complications were associated with significant increases in cost.