ABSTRACT Background Superior vena cava isolation (SVCI) is performed as an adjunct to pulmonary vein isolation (PVI) for atrial fibrillation, yet whether an empiric or trigger‐guided strategy is preferable remains uncertain. Prior meta‐analyses have been largely restricted to index procedures in paroxysmal AF and have not explicitly stratified by ablation strategy. We sought to address these gaps through a systematic review of available randomized evidence. Methods Major databases were searched through November 2025 for RCTs comparing PVI+SVCI versus PVI alone. Trials were stratified by strategy: empiric SVCI (performed irrespective of SVC ectopy) or trigger‐guided SVCI (performed only upon demonstrated SVC triggers). The primary outcome was atrial tachyarrhythmia recurrence (≥30 s) beyond the blanking period. Random‐effects models, pre‐specified subgroup analyses, meta‐regression, and GRADE certainty assessment were performed. Results Eight RCTs ( n = 1231) were included; most enrolled paroxysmal AF, while two incorporated non‐paroxysmal AF subtypes and one evaluated repeat ablation procedures. Overall, SVCI+PVI significantly reduced recurrence versus PVI alone (97/604 vs. 135/627; RR 0.77, 95% CI 0.61–0.97; p = 0.03; I 2 = 0%). On stratified analysis, empiric SVCI demonstrated a significant recurrence reduction (RR 0.70, 95% CI 0.53–0.92; p = 0.01; I 2 = 0%), while trigger‐guided SVCI did not reach statistical significance (RR 0.80, 95% CI 0.37–1.74; p = 0.57; I 2 = 52%). In paroxysmal AF ( n = 1038), adjunctive SVCI significantly reduced recurrence compared with PVI alone (RR 0.68, 95% CI 0.52–0.90; p = 0.01; I 2 = 0%). Fluoroscopy time was longer with SVCI; total procedure duration was comparable. Major complications were infrequent but numerically higher with SVCI+PVI (15/604 vs. 7/627; RR 1.96, 95% CI 0.87–4.38; p = 0.10). Meta‐regression identified no significant effect modifiers. GRADE certainty was high for overall and empiric analyses, and moderate for trigger‐guided SVCI. Conclusions Empiric SVCI significantly reduced AT/AF recurrence as an adjunct to PVI, while trigger‐guided SVCI did not demonstrate a significant benefit. These findings suggest SVC isolation confers benefit independent of prior trigger documentation, supporting the role of empiric SVCI as an adjunct to AF ablation.
Abstract 4341751: Outcomes Associated with Infective Endocarditis in Cardiac Intensive Care Unit Patients
Introduction: Infective endocarditis (IE) is a severe intracardiac infection, often requiring intensive care unit (ICU) admission. Despite early surgical intervention, mortality remains high. Data for patients admitted to the cardiac intensive care unit (CICU) is especially limited. Research Question: We aimed to investigate the short and long-term outcomes of patients with IE admitted to the CICU. Methods: We conducted a retrospective cohort study of adult patients admitted to the Mayo Clinic CICU (2007-2018) with confirmed acute IE, identified via database query and manual chart review. Patients were further categorized by cardiac surgery status: performed, indicated but declined, or not indicated. Primary outcomes were all-cause mortality at 30-days and 1-year, analyzed using Kaplan-Meier and Cox proportional-hazard analysis. Models were adjusted for known predictors. Results: Overall, 233 CICU patients met criteria for IE. Median age was 64.0 years; 49 were female. In total, 104 patients had native valve IE; 128 had prosthetic or implantable device-associated IE. Staphylococcus aureus was the most prevalent organism (42.7%) and was present in 72.4% of 30-day deaths. Cardiac surgery was indicated in 182 (78.1%) patients - 129 patients underwent surgery, while 53 declined; 48 patients did not have indications. By 30 days, 58 (24.9%) patients died; significant predictors included older age, higher illness severity scores, and greater need for critical care therapies. The 30-day mortality estimates were markedly higher for patients who declined surgery (60.4%, adj. HR 4.17, 95% CI 2.02-8.52, p <0.001), and lower for those who received surgery vs those without surgical indications (11.9% vs 23.8%, adj. HR 0.44, 95% CI 0.20-0.98, p=0.04) (Figure 1). By 1-year, 93 (39.9%) patients died, including 36 (20.5%) hospital survivors. The 1-year mortality estimates were markedly higher for patients who declined surgery (85.1%, adj. HR 5.46, 95% CI 2.87-10.39, p <0.001), but was similar for patients who received surgery to those without surgical indications (31.8% vs 29.3%, adj. HR 0.94, 95% CI 0.49-1.78, p=0.84) (Figure 2). Conclusion: IE requiring CICU admission carries substantial mortality despite acute management. Higher severity scores, comorbidities, and intensive care interventions predict mortality. Early cardiac surgery improved short-term outcomes, but long-term mortality remains high.
Prognostic impact of cardiac resynchronization therapy in wild-type transthyretin amyloid cardiomyopathy
AbstractIntroductionLittle is known regarding the prevalence and prognostic implications of non‐sustained ventricular tachycardia (NSVT) in patients with wild‐type transthyretin cardiac amyloidosis (ATTRwt‐CA). We aimed to investigate the prevalence of NSVT in patients with ATTRwr‐CA, and the association of NSVT with sustained ventricular arrhythmias (VA) and all‐cause mortality.MethodsIn a cohort of ATTRwt‐CA patients from 2011 to 2022 without prior sustained VA, we ascertained the presence and characteristics of NSVT during clinically indicated ambulatory Holter monitoring. Patients were stratified based on the presence of NSVT at baseline. The primary and secondary endpoints of sustained VA and all‐cause mortality, respectively, were assessed during follow‐up.ResultsThe cohort included 217 patients with ATTRwt‐CA (95% males, median age 75 years; median NYHA class 2). Baseline Holter monitoring demonstrated NSVT in 116 (53%) patients. During a median follow‐up of 27 months (IQR 16–45) after the index Holter monitor, 11 (5.1%) patients reached the primary endpoint of sustained VA (incidence 1.8 per 100 person‐years, all monomorphic VT), and 46 (21%) patients died. In univariable Cox proportional hazard model, NYHA class 3 or 4 heart failure (p = .048), the presence of NSVT (p = .04), the duration of longest NSVT run (p = .029), and the percentage of ventricular ectopy (p < .001) were associated with the primary outcome. When adjusting for age and NYHA class 3 or 4 heart failure, the presence of NSVT remained associated with the primary outcome (p = .03). All‐cause mortality was not significantly different between patients with and without NSVT. A cutoff for ventricular ectopy burden of 0.5%, the median for all patients in this study, was associated with increased risk in sustained VA (log‐rank p = .004) and mortality (log‐rank p = .02).ConclusionNSVT is highly prevalent among ATTRwt‐CA patients undergoing clinically indicated Holter monitoring and may confer an increased risk of incident sustained VA.
Substrate Characterization and Outcomes of Ventricular Tachycardia Ablation in Amyloid Cardiomyopathy: A Multicenter Study
BACKGROUND: Sustained ventricular tachycardia (VT) in cardiac amyloidosis is uncommon, and the substrate and outcomes of catheter ablation are not defined. METHODS: We included 22 consecutive patients (mean age, 68±10 years; male sex, 91%) with cardiac amyloidosis (ATTR [transthyretin], n=16; light chain, n=6) undergoing catheter ablation for VT/ventricular fibrillation (VF) between 2013 and 2023 in a retrospective, observational, international study. The primary efficacy outcome was recurrent VT/VF during follow-up, while the primary safety end point included major procedure-related adverse events. RESULTS: The indication for ablation was drug-refractory VT in 17 patients (77%), and premature ventricular complex–initiated polymorphic VT/VF in 5 patients (23%). Catheter ablation was performed using endocardial (n=17.77%) or endo-epicardial approaches (n=5.23%). Complete endocardial electroanatomical voltage maps of the left and right ventricles were obtained in 17 (77%) and 10 (45%) patients, respectively. Each patient had evidence of low-voltage areas, most commonly involving the interventricular septum (n=16); late potentials were recorded in 16 patients (73%). A median of 1 (1–2) VT was inducible per patient; 12 of the 26 mappable VTs (46%) originated from the interventricular septum. Complete procedural success was achieved in 16 patients (73%), with 4 (18%) major procedure-related adverse events. After a median follow-up of 32 (14–42) months, sustained VT/VF recurrence was observed in 9 patients (41%); survival free from VT/VF recurrence was 56% (95% CI, 36%–86%) at 36-month follow-up, and most patients remained on antiarrhythmic drugs. A significant reduction in per patient implantable cardioverter defibrillator therapies was noted in the 6-month period after ablation (before: 6 [4–9] versus after: 0 [0–0]; P <0.001). In multivariable analysis, complete procedural success was associated with reduced risk of recurrent VT/VF (hazard ratio, 0.002; P =0.034). CONCLUSIONS: Catheter ablation can achieve control of recurrent VT/VF in more than half of patients with cardiac amyloidosis, and the reduction in VT/VF burden post-ablation may be relevant for quality of life. Septal substrate and risk of procedure-related complications challenge successful management of patients with cardiac amyloidosis and VT/VF.
Substrate characterization and outcomes of ventricular tachycardia ablation in amyloid cardiomyopathy: a worldwide study
Abstract Background the electrophysiological substrate underpinning ventricular tachycardia (VT) in cardiac amyloidosis (CA) remains elusive, and outcomes of catheter ablation in this peculiar population are currently unknown. Purpose we sought to describe the electrophysiological substrate and clinical outcomes of VT ablation in a cohort of patients with CA. Methods we included 19 consecutive patients (mean age, 69±10 years; male sex, 89%) with CA (ATTR, n=13; AL, n=6) undergoing catheter ablation for VT/ventricular fibrillation (VF) between 2013 and 2023 in a retrospective, observational, international study, involving 7 referral European and North American electrophysiology units. The primary efficacy outcome was recurrent VT/VF during follow-up, while the primary safety outcome included major procedure-related adverse events. Results the indication for ablation was drug-refractory VT in 16 patients (84%), and PVC-initiated polymorphic VT/VF in 3 (16%). Catheter ablation was performed using endocardial (n=14, 74%) or endo-epicardial approaches (n=5, 26%). Complete endocardial electroanatomical voltage maps of the left and right ventricles were obtained in 14 (74%) and 6 (32%) patients, respectively. Each patient had evidence of low-voltage areas, most commonly involving the interventricular septum (n=12); late potentials were recorded in 13 patients (68%). A median of 1 (1-2) VTs were inducible per patient; in 10 subjects (43% of mappable VTs), activation mapping was consistent with septal VT origin. Complete procedural success was obtained in 13 patients (68%), at the expense of 4 (21%) major procedure-related adverse events. After a median follow-up of 36 (18-54) months, sustained VT/VF recurrence was observed in 9 patients (47%); survival free from VT/VF recurrence was 74% (95%CI, 56-96%) at 12 months, and 53% (95%CI, 34-94%) at 36-month follow-up; the majority of patients remained on antiarrhythmic drugs (Figure). Low-voltage QRS (HR,21.96; p=0.022) and complete procedural success (HR,0.08; p=0.029) were associated with recurrent VT/VF at multivariable analysis (Figure). Conclusions catheter ablation of VT/VF is associated with favorable acute and mid-term arrhythmia control, yet with substantial risk of procedure-related complications and long-term recurrences. Septal substrate and frailty challenge successful management of patients with CA and VT/VF.Multimodality evaluation of LV substrateMain Study Outcomes
Abstract 12996: Outcomes of Cardiac Resynchronization Therapy in Transthyretin Wild-Type Cardiac Amyloidosis
Introduction: Cardiac resynchronization therapy (CRT) has known benefit for heart failure (HF) with reduced left ventricular ejection fraction (LVEF) and dyssynchrony. However, very little is known about its benefit in infiltrative cardiomyopathies such as cardiac amyloidosis (CA) due to relative rarity of these conditions. Methods: This retrospective case series (2003-2021) comprised patients with HF due to transthyretin wild-type CA with (case) or without (control) CRT implant. Only controls with an indication for CRT or LVEF <40% were included. To further match disease severity, cases were 1:1 matched (propensity score tolerance 0.04) to controls for age, NYHA class, and CA stage (UK Staging). Primary outcome was MACE (major adverse cardiac events) which included stroke, myocardial infarction, HF hospitalization and cardiac mortality during a 3-year follow-up. Loss to follow-up was censored as per last visit date. LVEF and NYHA were noted closest to 1-year follow-up. Survival analysis for MACE was performed with Kaplan-Meier (KM) and multivariable cox regression models. Results: Study Cohort (n=160) had a mean age of 75.5 (SD 7.8) years and 97.5% were males. A majority had NYHA class 2 or 3 (92.3%) and CA stage 2 (42.2.%). Notably, median LVEF at baseline was lower in controls (33.5 vs 36.5; P = .001) and 77.5% of controls had an indication for CRT device. A total of 79 MACE events occurred, most frequent being HF hospitalization (n=45). KM curves were comparable for MACE events in the two groups (log-rank test; P = .059). Even after adjusting, as in table, CRT device was not associated with MACE events (adjusted HR 0.66; 95% CI 0.40-1.09; P = .106). Lastly, change in LVEF ( P = .84) and NYHA ( P = .86) at follow-up was similar in cases vs controls. Conclusions: The findings of this largest yet observational study to examine this question suggest that CRT in patients with transthyretin wild-type CA does not favorably impact outcomes for MACE events, improve LVEF or NYHA functional class.
Artificial Intelligence for the Detection and Treatment of Atrial Fibrillation
AF is the most common clinically relevant cardiac arrhythmia associated with multiple comorbidities, cardiovascular complications (e.g. stroke) and increased mortality. As artificial intelligence (AI) continues to transform the practice of medicine, this review article highlights specific applications of AI for the screening, diagnosis and treatment of AF. Routinely used digital devices and diagnostic technology have been significantly enhanced by these AI algorithms, increasing the potential for large-scale population-based screening and improved diagnostic assessments. These technologies have similarly impacted the treatment pathway of AF, identifying patients who may benefit from specific therapeutic interventions. While the application of AI to the diagnostic and therapeutic pathway of AF has been tremendously successful, the pitfalls and limitations of these algorithms must be thoroughly considered. Overall, the multifaceted applications of AI for AF are a hallmark of this emerging era of medicine.
Computerized electrocardiogram data transformation enables effective algorithmic differentiation of wideQRScomplex tachycardias
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.