Srivathsan, Komandoor

Background: Pulsed Field Ablation (PFA) has gained widespread adoption for pulmonary vein isolation (PVI) due to its tissue selectivity and safety profile. However, its role in cavotricuspid isthmus (CTI) ablation for typical atrial flutter is less defined. This study compares CTI ablation using PFA versus radiofrequency ablation (RFA) in patients undergoing PVI exclusively with PFA. Research Question: We hypothesized that in patients undergoing PFA-based PVI, CTI ablation using PFA would reduce procedure and fluoroscopy times without increasing complication or flutter recurrence rates compared to RFA. Methods: We retrospectively analyzed patients who underwent CTI ablation with either PFA or RFA alongside PFA PVI between 2024 – 2025 across all Mayo Clinic sites. Baseline characteristics, procedural parameters, acute success, and 12-month arrhythmia recurrence were compared between groups. All patients received standard follow-up, including ECGs and Holter monitoring. Results: A total of 350 patients were included (CTI PFA: n = 126; CTI RFA: n = 224). Patients in the PFA group were older (68.8 ± 8.5 vs. 65.7 ± 10.1 years; p <0.01) and had higher CHA2DS2-VASc scores (2.84 ± 1.57 vs. 2.45 ± 1.45; p = 0.02). Fluoroscopy (18.9 ± 9.1 vs. 25.2 ± 23.3 min; p < 0.01 ) and procedure times (172.6 ± 22.4 vs. 224.7 ± 74.2 min; p < 0.01) were significantly lower in the PFA group. Complication rates (8.7% vs. 4.9%; p = 0.15) and typical flutter recurrence (3.1% vs. 1.7%; p = 0.46) were similar between groups during a mean follow-up of 125 days. Conclusion: In patients undergoing PVI with PFA, CTI ablation using PFA is associated with significantly reduced procedure and fluoroscopy times compared to RFA, without increased complications or arrhythmia recurrence. These findings support the feasibility and efficiency of PFA for typical flutter ablation when performed during PFA-based AF procedures.

Background: Pulsed field ablation (PFA) has become a cornerstone for atrial fibrillation ablation. Multiple platforms have been developed and approved worldwide, and routine screening for asymptomatic brain injury (ABI) has been included in several trials as part of the safety assessment of this technology. The incidence by catheter/platform, predictors of occurrence, and clinical impact remain incompletely understood. Research Question: In patients with atrial fibrillation undergoing pulmonary vein isolation, does the incidence of ABI vary between different PFA platforms? Methods: We searched the MEDLINE/PubMed, Embase, and Cochrane Central Register of Controlled Trials databases for studies reporting on patients who underwent PFA and post-procedure brain MRI to screen for ABI. The review was conducted in accordance with PRISMA guidelines. A random-effects proportion meta-analysis was performed, with subgroup analysis based on the PFA platform used. For studies including a thermal ablation control group, risk ratio (RR) was used to compare outcomes. Finally, a meta-regression was conducted to identify potential predictors of ABI incidence. Results: A total of 19 studies reporting data from 742 patients who underwent post-ablation brain MRI were included in this review. The pooled incidence of silent cerebral events (new findings visible only on DWI sequences) and silent cerebral lesions (new findings on both DWI and FLAIR sequences) was 5% each (95% CI, 3%–8%). The pooled incidence of any ABI was 10% (95% CI, 8%–13%). A platform-level subgroup analysis demonstrated comparable outcomes across the platforms with available data (Figure 1). The meta-regression included age, sex, CHA2DS2-VASc score, and incidence of symptomatic stroke/TIA, but no statistically significant associations were identified. In the four studies that included a thermal ablation control group, there was no significant difference in ABI incidence between PFA and thermal ablation (RR: 1.37; 95% CI, 0.68–2.74; P = 0.38; I2 = 16%) (Figure 2). Seven studies reported follow-up MRI in patients who presented with an ABI. Among 20 patients with ABI after ablation, radiologic lesions persisted in 2 patients. Conclusion: ABI is a relatively frequent finding following PFA; however, current evidence does not reveal significant differences between available platforms. Radiologic findings tend to be transient, suggesting a limited long-term clinical impact.

Background: A blanking period allowing for atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) has historically been standardized to 90 days. With the recent introduction of pulsed field ablation (PFA) for PVI and emerging in vitro data suggesting a shorter inflammatory timeframe, it remains unclear whether recurrences during this 90-days period reflect incomplete procedural success or merely transient inflammatory changes. Research Question: In patients undergoing PVI with PFA, do early AF recurrences at 30, 60, and 90 days predict late AF recurrences beyond the standardized 90-day blanking period? Methods: Patients undergoing PFA for AF were retrospectively included. Procedures were performed under general anesthesia, and high-density (HD) mapping, with PVI and additional ablation lines applied at the operator’s discretion. PFA catheters included Farawave, PulseSelect, and Sphere-9. AF recurrences were defined as documented episodes on 12-lead ECG or cardiac monitoring devices, confirmed by interpretation from an experienced cardiologist. Survival analyses were conducted based on the occurrence of early recurrences at 30, 60, and 90 days post-ablation. Kaplan-Meier curves and hazard ratios were reported. This study was approved by our institutional review board. Results: To the best of our knowledge, this is the largest real-world study reporting outcomes of PFA for AF in the United States. A total of 1,214 patients were included in the analysis. Mean age was 66.4 years; 31.9% were female, and 22.4% underwent redo PVI. Six-month AF recurrence-free survival was 79% (95% CI, 75–83%) for the overall cohort. Patients experiencing early recurrence at 30, 60, and 90 days had a significantly higher risk of AF recurrence beyond the standardized 90-day blanking period (HR 4.0, 95% CI 2.7–5.9, P < 0.01; HR 5.0, 95% CI 3.6–7.1, P < 0.01; and HR 6.9, 95% CI 4.9–9.6, P < 0.01, respectively). Conclusion: Early recurrences at 30, 60, and 90 days post-ablation are strongly associated with atrial fibrillation recurrence beyond the 90-day blanking period. These findings challenge the traditional concept of blanking period after PFA and suggest that early recurrence may indicate incomplete procedural success rather than transient inflammation.

Abstract Aims Patients with end-stage renal disease (ESRD) and atrial fibrillation present a challenge for thromboembolic prevention, given their elevated risks of both thromboembolism and bleeding. Anticoagulants carry a higher bleeding risk in this population without clear evidence of thromboembolic benefit. This study aims to define the role of left atrial appendage occlusion (LAAO) as a preventive strategy for patients with ESRD. Methods and results A systematic literature review was conducted to identify studies reporting outcomes in patients with ESRD who underwent LAAO. Meta-analyses of aggregate and individual patient data were performed to evaluate acute and long-term outcomes and compare them with those of patients without ESRD. Seventeen studies reporting data from 24 127 patients, including 1047 with ESRD, were included. Procedural complications were more common in patients with ESRD (RR 2.23; P = 0.02), with a pooled rate of 4% (95% CI, 1–9%). There was no significant difference in thromboembolic event rates during follow-up between the groups (IRR 1.44; P = 0.16), but major bleeding incidence was higher among patients with ESRD (IRR 1.84; P &lt; 0.01). Individual patient-level data from seven studies comprising 4745 patients (268 with ESRD) were obtained and analysed. Similarly, there was no significant association between ESRD and stroke/TIA incidence (HR, 1.22; 95% CI, 0.66–2.26), but major bleeding was higher on patients with ESRD (HR, 1.65; 95% CI, 1.01–2.69). Conclusion LAAO represents a feasible option for thromboembolic prevention in patients with ESRD, although these patients have an increased risk of complications and bleeding.

ABSTRACT Cavotricuspid isthmus ablation (CTI) is a first‐line therapy in patients with typical atrial flutter. With the advent of pulsed field (PF) as a new energy source, we sought to evaluate the use of PF for CTI ablation. A systematic literature search was conducted on the use of PF for CTI‐flutter up to December 2024. A meta‐analysis was performed for studies reporting pooled data, while individual case reports were reviewed and summarized. The mean number of PF applications, acute success rate, and prevalence of coronary vasospasm were evaluated. Eleven studies with pooled data from 155 patients were included. All patients had an acute block of the CTI. The mean number of PFA applications was 7.78 (95% CI 6.53–9.48). The incidence of ST‐elevation was 0.04% (95% CI 0–2.23%). Subclinical vasospasm was documented in 45% (95% CI 32%–59%) of patients who underwent periprocedural coronary angiography. Prophylactic use of nitrates showed a trend toward reducing the incidence of subclinical vasospasm (RR 0.24, 95% CI 0.06–1.06, p = 0.059). Twelve cases with patient‐level data were included; six reported complications, including ST elevation and conduction disturbances. PFA for CTI flutter demonstrates high acute success; however, evidence regarding the durability of the block is limited. Clinical vasospasm with ST segment elevation is uncommon but can lead to life‐threatening complications. The incidence of subclinical vasospasm is high, and nitrates tend toward reducing this phenomenon. To date, the role of PFA for this condition appears to be limited.

Abstract Background Epicardial access for ventricular arrhythmia (VA) ablation has become integral, particularly in non-ischemic and arrhythmogenic right ventricular cardiomyopathy. General anesthesia (GA) or conscious sedation (CS) is typically employed to minimize patient discomfort and movement during epicardial access. This study aimed to identify key differences in baseline characteristics and procedural outcomes between patients undergoing GA or CS. Purpose This study seeks to compare baseline characteristics, procedural details, and outcomes between patients receiving GA versus CS during epicardial access for VA ablation. Understanding these differences may inform procedural planning and patient selection to optimize outcomes. Methods Patients who underwent epicardial access for VA ablation from 2004 to 2024 were included. Baseline characteristics, procedural details, and outcomes were collected and compared using t-tests between GA and CS patients. Additionally, Kaplan-Meier survival analysis was conducted to compare survival in GA and CS groups, stratified by VA type (Ventricular Tachycardia (VT) and Premature Ventricular Complexes (PVC)). Results The study included 265 patients, with 148 receiving GA and 117 receiving CS. Significant differences in baseline characteristics were observed between the groups. CS patients had a higher ejection fraction (48.71% vs. 40.97%, p &lt; 0.01) and a greater proportion of structurally normal hearts (35% vs. 8%, p &lt; 0.01). GA patients had a higher comorbidity burden, including a greater prevalence of diabetes (21% vs. 10%, p = 0.02), heart failure (70% vs. 41%, p &lt; 0.01), hypertension (48% vs. 33%, p = 0.01), device in-situ (80% vs. 50%, p &lt; 0.01), and ischemic heart disease (25% vs. 12%, p = 0.01). PVC ablation was more common in CS patients (37% vs. 18%, p &lt; 0.01). Fluoroscopy time was longer in CS patients (74.94 vs. 60.42 mins, p &lt; 0.01), and GA patients required more ablation lesions (34.13 vs. 24.06, p &lt; 0.01). Kaplan-Meier survival analysis showed no significant differences in survival between GA and CS groups for either VT or PVC. Complication rates and the combined endpoint of recurrence, heart transplant, or death also did not differ significantly between groups. Conclusions Patients undergoing epicardial access with GA had a higher burden of comorbidities and required more ablation lesions, while those with CS generally had better baseline cardiac function and were more frequently treated for PVCs. Although fluoroscopy time was longer in CS patients, complication rates and the combined outcome of recurrence, heart transplant, or death did not significantly differ between groups. Kaplan-Meier analysis further demonstrated similar survival outcomes between GA and CS groups for both VT and PVC. These findings suggest that both GA and CS can be safely used for epicardial access in VA ablation, with each approach tailored to the patient’s clinical profile and procedural needs.Table 1 Figure 1

Abstract Background Cardiac sarcoidosis (CS) is a rare condition associated with electrical conduction disturbances. Ventricular tachycardia (VT) may be a life-threatening manifestation of CS. Immunosuppressants and antiarrhythmic drugs (AADs) are considered first-line management, but for refractory cases, an implantable cardioverter-defibrillator (ICD) and VT ablation may be required. Purpose This study aims to document predictors for complete acute success after VT ablation in patients with CS. Methods This was a post hoc analysis from an observational study that included patients who underwent VT ablation for cardiac sarcoidosis at our institution from 2007 to 2024. Patients with suspected, clinically diagnosed, or histologically diagnosed CS, according to the JCS 2016 guidelines, were included. The cohort was divided into two groups: patients with complete acute success, defined as no VT induced at the end of the procedure, and patients with no acute success, which included patients with partial success, unsuccessful procedures, and no inducibility test at the end of the procedure. After univariate analysis, variables with an uneven distribution between the two groups (p &lt; 0.1) were included in a multivariate logistic regression analysis. Results A total of 95 patients were enrolled. Complete acute success was achieved in 40 patients (42%). The mean age was 56.7 ± 10.1 years, and 14 (15%) patients were female. Extracardiac sarcoidosis involvement was reported in 38 (40%) patients. Only one patient in the complete acute success group did not have an ICD. Before VT ablation admission, 40 (42%) patients were on immunomodulators, and 78 (82%) on AADs. The mean ejection fraction in the complete acute success group was 44.5% ± 11.9, compared to 41.7 ± 12.0 in the no-complete success group. Among the 53 patients who underwent a PET scan in the 6 months before ablation, 17 (32%) showed active inflammation based on 18FDG uptake, with no significant difference between the two groups. LGE was present in 57 of 58 patients with a cardiac MR before ablation. Septal involvement was more common in the complete success group (86% versus 58%; OR, 4.41; 95% CI, 1.02-27.5; P = 0.039). A multifocal distribution was also more common in the complete success group (95% versus 67%; OR, 10.17; 95% CI, 1.3-468; P = 0.011). Fluoroscopy and total procedure time were comparable between both groups. The presence of clinical VT with an RBBB morphology was more common in the no-complete success group (54% versus 79%; OR, 0.31; 95% CI, 0.09-1.02; P = 0.03). In the multivariate analysis, epicardial LGE was associated with lower odds of complete acute success (adjusted OR, 0.087; 95% CI, 0.008-0.944; P = 0.04). Conclusions In our population, the presence of epicardial LGE on cardiac MR prior to VT ablation was an independent predictor of no complete acute success.

Background: Cavotricuspid isthmus ablation (CTI) is a first line therapy in patients with typical atrial flutter. With the advent of Pulsed Field (PF) as a new energy source, we sought to evaluate the use of PF for CTI ablation. A systematic literature search was conducted on the use of PF for CTI-flutter up to December 2024. A meta-analysis was performed for studies reporting pooled data, while a patient-level summary was done for reports with available individual data. The mean number of PF applications, acute success rate, and prevalence of coronary vasospasm were evaluated. Results: Eleven studies with pooled data from 155 patients were included. All patients had an acute block of the CTI. The mean number of PFA applications was 7.78 (95% CI 6.53–9.48). The incidence of ST-elevation was 0.04% (95% CI 0-2.23%). Subclinical vasospasm was documented in 45% (95% CI 32%–59%) of patients who underwent periprocedural coronary angiography. Prophylactic use of nitrates showed a trend toward reducing the incidence of subclinical vasospasm (RR 0.24, 95% CI 0.06–1.06, p=0.059). Twelve cases with patient-level data were included; six reported complications, including ST elevation and conduction disturbances. Conclusion: PFA for CTI flutter demonstrates high acute success; however, evidence regarding the durability of the block is limited. Clinical vasospasm with ST segment elevation is uncommon but can lead to life-threatening complications. The incidence of subclinical vasospasm is high, and nitrates trend toward reducing this phenomenon. To date, the role of PFA for this condition appears to be limited.