Asirvatham, Samuel J.

Background: Recognition of the causes of early mortality after transvenous lead removal (TLR) is an essential step for the development of quality improvement programs. Objective: This study sought to determine the causes of early mortality after TLR and to further understand the circumstances surrounding death after TLR. Methods: We performed a retrospective analysis of all patients undergoing TLR from January 1, 2001, to January 1, 2021 at the Mayo Clinic (Rochester, Phoenix, and Jacksonville). Causes of death were identified through a detailed chart review of the electronic health record from within the Mayo Clinic system and outside records when available. The causes of death were further characterized based on whether it was related to the TLR procedure. Results: A total of 2,319 patients were included in the study. The overall 30-day all-cause mortality rate was 3%. Among all 30-day deaths, infection was the most common primary cause of death (42%). This was followed by decompensated heart failure (17%), procedure-related death (10%), sudden cardiac arrest (7%), and respiratory failure (6%). The 30-day mortality rate directly due to complications associated with the TLR procedure was 0.3% due to vascular tear and cardiac perforation. A third of deaths (33%) occurred after discharge from index hospitalization, among which 43% were readmitted before their death, 35% died at home or a nursing facility, and 22% were discharged on comfort care and died in hospice. The main reasons for readmission prior to death were sepsis and decompensated heart failure. Conclusions: The majority (90%) of 30-day mortality after TLR was not due to complications associated with TLR procedures. The primary causes were infection and decompensated heart failure. This highlights the importance of further research to reduce postoperative mortality from these factors, including deaths after hospital discharge.

Background : Modulation of the cardiac autonomic nervous system (ANS) is a promising adjuvant therapy in the treatment of atrial fibrillation (AF). In pre-clinical models, pulsed field (PF) energy has the advantage of selectively ablating the epicardial ganglionated plexi (GP) that govern the ANS. Objective: This study aims to demonstrate the feasibility and safety of epicardial ablation of the GPs with PF during cardiac surgery with a primary efficacy outcome of prolongation of the atrial effective refractory period (AERP). Methods : In a single-arm, prospective analysis, patients with or without a history of AF underwent epicardial GP ablation with PF during coronary artery bypass grafting (CABG). AERP was determined immediately pre- and post- GP ablation to assess cardiac ANS function. Holter monitors were performed to determine rhythm status and Heart Rate Variability (HRV) at baseline and at 1 month post-procedure. Conclusions : This study demonstrates the safety and feasibility of epicardial ablation of the GP using PF to modulate the ANS during cardiac surgery. Large, randomized analyses are necessary to determine whether epicardial PF ablation can offer a meaningful impact on the cardiac ANS and reduce AF. Results : Of 24 patients, 23 (96%) received the full ablation protocol. No device-related adverse effects were noted. GP ablation resulted in a 20.7% ± 19.9% extension in AERP (P < 0.001). Post-operative AF was observed in 7 (29%) patients. Holter monitoring demonstrated an increase in mean heart rate (74.0±8.7 vs 80.6±12.3, P=0.01). There were no significant changes in HRV. There were no study-related complications.

Background: Atypical Atrial Flutter (AAFL) prevalence is increasing due to the escalating Atrial Fibrillation (AF) ablations and cardiac surgeries. We wanted to explore the outcome of the AAFL ablation, considering the recent changes in mapping and ablation. Methods: This study was approved by the Institutional Review Board (IRB) of Mayo Clinic hospital. We retrospectively studied 419 patients who had undergone AAFL ablation at Mayo Clinic from January 2017 to June 2022. Thirteen patients declined research authorization, and 19 patients were lost to follow-up during the 90-day blanking period, resulting in a sample size of 387. The median follow-up time for patients was 25.7 months (95% CI 23.7, 32.3). Results: Recurrent symptoms with documentation of atrial arrhythmia Occurred in 226/387 (58.4%) patients, of which 151/226 (66.8%) occurred within the first year. The median time to recurrence was 8.5 months (max 57.8 months). Eleven patients died during the study period, 9 of whom experienced recurrence prior to death. Overall, the median recurrence-free survival (RFS) time was 16.6 months (95% CI 13.2, 20.0) with a 1-year RFS rate of 57.2% (95% CI 52.2, 62.7%). Acute termination occurred 324/387 (83.7%) during the ablation. The 1-year RFS rate was 58.9% (95% CI 53.5%, 64.9%) for patients with acute termination and 49.0% (95% CI 37.9%, 63.4%) for those without acute termination. The rate was not significantly different based on acute termination status (p = 0.11). Conclusions: The one-year RFS rate of 57.2% following AAFL ablation, even though 83.7% achieved acute termination during the procedure, signifies the extent of the underlying substrate abnormalities.

Background: Recognition of the causes of early mortality after atrial fibrillation (AF) catheter ablation is essential for the improvement of patient safety. This study sought to determine the causes of early mortality (≤90 days) after AF ablation. Methods: We performed a retrospective analysis of AF ablation from January 1, 2013, to December 1, 2021 at the Mayo Clinic (Rochester, Phoenix, and Jacksonville). Causes of death were identified through a comprehensive chart review of the electronic health record from within the Mayo Clinic system and outside records when available. Results: A total of 6723 patients were included in the study. The 90-day all-cause mortality rate was 0.22% (n=15). Among all 90-day deaths, majority of the deaths (73.3%) did not have a direct relationship with the procedure. Sudden death was the most common cause of early death (20%), followed by peri-procedural stroke (13%), respiratory failure (13%), atrioesophageal fistula (13%), infection (7%), heart failure (7%), and traumatic brain injury (7%). The 90-day mortality rate directly due to AF ablation procedural complications was 0.06% (n=4). Conclusions: AF ablation procedure has a 90-day mortality of 0.22%, and the most common cause of early mortality was sudden death. The majority (73.3%) of early mortality was not directly associated with a procedural complication, and the mortality rate due to complications associated with the AF ablation procedure was low at 0.06%. Further studies are required to investigate causes and risk factors associated with sudden death in this patient population.

AbstractIntroductionData regarding ventricular tachycardia (VT) or premature ventricular complex (PVC) ablation in patients with aortic valve (AV) intervention (AVI) is limited. Catheter ablation (CA) can be challenging given perivalvular substrate in the setting of prosthetic valves. We sought to investigate the characteristics, safety, and outcomes of CA in patients with prior AVI and ventricular arrhythmias (VA).MethodsWe identified consecutive patients with prior AVI (replacement or repair) who underwent CA for VT or PVC between 2013 and 2018. We investigated the mechanism of arrhythmia, ablation approach, perioperative complications, and outcomes.ResultsWe included 34 patients (88% men, mean age 64 ± 10.4 years, left ventricular (LV) ejection fraction 35.2 ± 15.0%) with prior AVI who underwent CA (22 VT; 12 PVC). LV access was obtained through trans‐septal approach in all patients except one patient who had percutaneous transapical access. One patient had combined retrograde aortic and trans‐septal approach. Scar‐related reentry was the dominant mechanism of induced VTs. Two patients had bundle branch reentry VTs. In the VT group, substrate mapping demonstrated heterogeneous scar that involved the peri‐AV area in 95%. Despite that, the site of successful ablation included the periaortic region only in 6 (27%) patients. In the PVC group, signal abnormalities consistent with scar in the periaortic area were noted in 4 (33%) patients. In 8 (67%) patients, the successful site of ablation was unrelated to the periaortic area. No procedure‐related complications occurred. The survival and recurrence‐free survival rate at 1 year tended to be lower in VT group than in PVC group (p = .06 and p = .05, respectively) with a 1‐year recurrence‐free survival rate of 52.8% and 91.7%, respectively. No arrhythmia‐related death was documented on long‐term follow‐up.ConclusionCA of VAs can be performed safely and effectively in patients with prior AVI.

Background Left (LAAA) and right atrial appendage aneurysms (RAAA) are rare entities, and their natural history, management, and long-term outcomes are not well studied. Methods This retrospective review includes all patients from 2000 to 2021 with atrial appendage aneurysms at our institution identified using an electronic search tool. LAAA and RAAA were confirmed using multimodality imaging and intraoperative findings. Results We identified 13 (87%) patients with LAAA and 2 (13%) with RAAA. At diagnosis, 11 (73%) were female, mean age was 51.4 ± 18.8 years, and ejection fraction 56.5 ± 13.1%. Three (20%) patients had congenital heart disease including 2 (13%) with atrioventricular septal defects and 1 (7%) with congenitally corrected transposition. LAAA/RAAA was diagnosed due to new-onset atrial fibrillation (AF) in 6 (40%) patients and embolic stroke in 2 (13%). Ten patients had preexisting AF diagnosed 2.9 ± 1.4 years earlier at a mean age of 50.2 ± 15.5 years. Thrombus within the aneurysm was identified in 2 (15%) LAAA patients. All patients were on anticoagulation and follow-up of the cohort from diagnosis was 7.1 ± 6.2 years. Eleven (73%) patients were surgically managed with 7 (64%) lesions excised, 1 (9%) stapled, and 3 (27%) ligated. Postoperative complications occurred in 2 (18%) patients with 1 (7%) developing tricuspid regurgitation and another with pericardial effusion and tamponade. Conclusions Atrial appendage aneurysm is a rare disease and nearly half of patients present with AF. Surgical treatment with concomitant AF ablation is a reasonable and safe management option.

AbstractBackgroundAccurate automated wide QRS complex tachycardia (WCT) differentiation into ventricular tachycardia (VT) and supraventricular wide complex tachycardia (SWCT) can be accomplished using calculations derived from computerized electrocardiogram (ECG) data of paired WCT and baseline ECGs.ObjectiveDevelop and trial novel WCT differentiation approaches for patients with and without a corresponding baseline ECG.MethodsWe developed and trialed WCT differentiation models comprised of novel and previously described parameters derived from WCT and baseline ECG data. In Part 1, a derivation cohort was used to evaluate five different classification models: logistic regression (LR), artificial neural network (ANN), Random Forests [RF], support vector machine (SVM), and ensemble learning (EL). In Part 2, a separate validation cohort was used to prospectively evaluate the performance of two LR models using parameters generated from the WCT ECG alone (Solo Model) and paired WCT and baseline ECGs (Paired Model).ResultsOf the 421 patients of the derivation cohort (Part 1), a favorable area under the receiver operating characteristic curve (AUC) by all modeling subtypes: LR (0.96), ANN (0.96), RF (0.96), SVM (0.96), and EL (0.97). Of the 235 patients of the validation cohort (Part 2), the Solo Model and Paired Model achieved a favorable AUC for 103 patients with (Solo Model 0.87; Paired Model 0.95) and 132 patients without (Solo Model 0.84; Paired Model 0.95) a corroborating electrophysiology procedure or intracardiac device recording.ConclusionAccurate WCT differentiation may be accomplished using computerized data of (i) the WCT ECG alone and (ii) paired WCT and baseline ECGs.

Ablation has recently emerged as a tool for modulating gastric electrical activation and may hold interventional potential for disorders of gastric function. However, previous studies have been limited to the acute intraoperative setting. This study now presents the safety of gastric ablation after postsurgical recovery and healing. Localized electrical conduction blocks created by ablation remained after 2 wk of healing, and no perforation or other complications were observed over the postsurgical period.

Background: Left ventricular outflow tract obstruction may occur following transcatheter mitral valve replacement in the setting of mitral annular calcification. Methods: We present a case series whereby preemptive septal radiofrequency ablation (RADIO-TMVR) was used to augment the left ventricular outflow tract for transcatheter mitral valve replacement in 4 patients at risk for left ventricular outflow tract obstruction despite alcohol septal ablation. Results: All patients were female, average age of 74.9 (68.8–80.4) years. Baseline ejection fraction was 71% (63%–75%). Mean mitral valve area was 1.28 (range, 1.0–1.59) cm 2 . Mean mitral valve gradient at rest was 9.5 (range, 7–11) mm Hg. New York Heart Association symptoms were III to IV at baseline. Patients underwent preemptive septal radiofrequency ablation to prevent left ventricular outflow tract obstruction with transcatheter mitral valve replacement a range between 69 and 154 days after alcohol septal ablation. Procedural time was 384 (337–424) minutes with a fluoroscopic time of 31 (14–71) minutes. Radiofrequency ablation time was 132 (100–175) minutes. As anticipated, 3 patients developed complete heart block and underwent pacemaker implantation, whereas 1 had a preexisting pacemaker. One patient developed groin hematoma and heart failure exacerbation. There were no peri-procedural deaths. Preemptive septal radiofrequency ablation to prevent left ventricular outflow tract obstruction with transcatheter mitral valve replacement resulted in septal end-diastolic wall thickness reduction compared with baseline (28.6%, 30.4%, 30.3%, and 11.1%) and following alcohol septal ablation (23.1%, 12%, 8.5%). Valve replacement in the setting of mitral annular calcification was performed in all patients 89 (range, 38–45) days after preemptive septal radiofrequency ablation to prevent left ventricular outflow tract obstruction with transcatheter mitral valve replacement. Two patients had concomitant laceration of the anterior mitral leaflet to further augment the neo-left ventricular outflow tract. Postprocedure, New York Heart Association symptoms improved to class I (3 patients) and class II (1 patient). Conclusions: In at-risk individuals, preemptive septal radiofrequency ablation may be an effective strategy at preventing left ventricular outflow tract obstruction with transcatheter mitral valve replacement.