Natale, Andrea

Abstract Background and Aims Stroke and systemic embolism are recognized but poorly characterized complications of atrial fibrillation (AF) and left atrial flutter (AFL) catheter ablation. Their incidence, outcomes, and procedural associations remain insufficiently defined. Methods Retrospective global registry was initiated by the European Heart Rhythm Association Scientific Committee. A secure database captured data from ablation centres worldwide on general AF and left AFL ablation activity, as well as detailed information on patients with symptomatic embolic events between 2017 and 2024. Results Overall, 204 centres reported 335 743 ablation procedures and 550 embolic events (incidence 0.16%). Centre-level rate ranged from 0% to 3.1%. Most events were cerebral (94%), followed by peripheral (5%), and combined (1%). Coronary air embolism accounted for 62% of all peripheral events. Intraprocedural events occurred in 93 patients (17%), within 72 h in 357 (78%) and beyond 72 h in 100 (22%); 128 cases (23%) were diagnosed after hospital discharge. Nonparoxysmal AF (0.23% vs 0.15%; P < .001), centre experience, and ablation energy source (radiofrequency, 0.16%; cryoballoon, 0.16%; pulsed field ablation, 0.25%; laserballoon, 0.88%; P < .001) were associated with embolic risk. Median NIHSS score after stroke was 4 (interquartile range, 2–9). Three-month follow-up was available for 518 patients with embolism (95%): 181 (35%) had sequelae and 16 (3%) died. Conclusions Symptomatic embolic events are infrequent but associated with significant morbidity and mortality. Most events occur early, though a substantial proportion arise later. Higher event rates were observed with laser and possibly with pulsed field ablation. A greater centre experience was associated with a lower embolism incidence.

Background Recent technologies enable real‐time 3‐dimensional intracardiac echocardiography (ICE) with the advantages of 2‐dimensional ICE and imaging capabilities of transesophageal echocardiography. The purpose of this study is to evaluate the real‐world, multicenter safety and performance of a novel 3‐dimensional ICE system in a variety of cardiac interventions used in standard clinical practice. Methods This prospective, multicenter, observational, single‐arm study enrolled patients who were scheduled for an invasive cardiac procedure involving guidance with ICE and followed until discharge or ≤48 hours postprocedure. Intracardiac imaging was performed with the 3‐dimensional ICE catheter, VeriSight Pro (Philips Inc.). Fluoroscopy was used in all cases and transesophageal echocardiography was used in some cases. The primary safety end point was device‐related adverse events. The primary efficacy end point included technical success, imaging success, and clinical success. Results Between October 2021 and November 2022, 155 patients were enrolled and screened. Percutaneous interventions performed included atrial septal defect/patent foramen ovale closures, left atrial appendage occlusion, catheter ablations, and valve procedures. No adverse events were related to the device or procedure. The technical, imaging, and clinical success rates were 98.7% (95% CI, 95.4%–99.8%), 96.1% (95% CI, 91.8%–98.6%), 94.8% (95% CI, 91.8%–98.6%), respectively. Overall, the VeriSight Pro ICE image quality was assessed to be “acceptable” or greater in relation to reference image modality among 96.2% (149 of 155) of procedures. Conclusions VeriSight ICE imaging is safe and effective in the guidance of a wide variety of percutaneous cardiovascular procedures and has provided successful and high‐quality imaging of cardiac structures.

BACKGROUND: Patients with arrhythmogenic mitral valve prolapse syndrome are at increased risk for life-threatening ventricular arrhythmias, but studies have been limited by small sample sizes. We sought to assemble an international arrhythmogenic mitral valve prolapse syndrome registry to delineate the clinical, imaging, and treatment characteristics of patients with arrhythmogenic mitral valve prolapse syndrome who survived sudden cardiac arrest (SCA) or had sustained ventricular tachycardia (VT) or ventricular fibrillation. METHODS: In this descriptive registry, we characterized patients with arrhythmogenic mitral valve prolapse syndrome who survived SCA, sustained VT, or ventricular fibrillation. Deidentified data were abstracted locally and combined centrally. RESULTS: We included 148 patients who had SCA or VT/ventricular fibrillation. Patients had a mean age of 43.7±15.4 years; 68% were women, 73% had bileaflet prolapse, 65% had mitral annular disjunction, 67% had nonsustained VT, and 59% had inferolateral T-wave inversions. Syncope (n=54, 48%) and anterolateral T-wave inversion (n=26, 22%) were relatively common. Catheter ablation was performed in 50 (35%) patients for premature ventricular complexes and in 18 (17.7%) patients for VT. Sites of origin for arrhythmias were commonly in the papillary muscles, fascicles, mitral annulus, and inferior/inferolateral left ventricle. CONCLUSIONS: In this international descriptive registry of patients with arrhythmogenic mitral valve prolapse syndrome and SCA, patients were young, women, and had bileaflet mitral valve prolapse, mitral annular disjunction, inferolateral T-wave inversions, and nonsustained VT. A history of syncope and anterolateral T-wave inversions was relatively common in patients who survived SCA or sustained VT/ventricular fibrillation.

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.

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

Introduction: Left atrial appendage closure (LAAC) device for stroke prevention is a safe and effective alternative to oral anticoagulation (OAC) in patients with atrial fibrillation (AF). The safety of performing LAAC on uninterrupted warfarin (UW) compared to interrupted warfarin (IW) is currently unknown. Hypothesis: Complication rates of performing LAAC on UW vs. IW will be similar. Methods: We reviewed the data from the second half of PROTECT-AF trial, PREVAIL trial, CAP and CAP2 registries. Patients were categorized to the UW group if INR on the day of the procedure was ≥2 and to the IW group if INR was <2. Procedural complications within 7 days of LAAC were reviewed. An association between complications and AC strategy was analyzed. Results: Data from 1580 patients were reviewed and 294 patients (18.6%) received LAAC on UW. The UW group had a mean INR of 2.4±0.4 and IW group had a mean INR of 1.3±0.3. There were several differences in baseline characteristics: lower BMI in the UW group (28.6±5.3 vs 29.5±6.0, p=0.01), fewer patients with hypertension in the UW group (87.1% vs 91.1%, p=0.04), lower HAS-BLED score in the UW group (2.0±1.0 vs 2.1±1.0, p<0.01), and more patients with persistent AF in the UW group (37.1% vs 26.4%, p<0.01). Overall, there were no significant differences in total or individual complication rates between the two groups (UW 5.1% vs IW 6.1%, p=0.59). Although not statistically significant, lower event rates were noted in the UW group for the following: stroke (0% vs 0.3%, p>0.99), pericardial effusion requiring intervention (1.7% vs 1.8%, p>0.99), pseudoaneurysm (0% vs 0.4%, p=0.59), hematoma (0% vs 0.2%, p>0.99), and device embolism (0% vs 0.2%, p=1.0). The UW group had statistically insignificant higher events rates of AV fistula (0.3% vs 0%, p=0.19) and major bleeding requiring transfusion (1% vs 0.5%, p=0.38). In addition, there was no significant difference in periprocedural ischemic stroke (0% vs 0.3%, p>0.99). Conclusion: In this retrospective analysis, no significant difference was observed in procedural complication rates when performing LAAC on UW vs. IW. These results suggest that LAAC can be safely performed without interruption of OAC.

Introduction: Incident cardiac arrhythmias are common in hospitalized COVID-19 patients, but the impact of a second incident cardiac arrhythmia during hospitalization on clinical outcomes remain unclear. Hypothesis: The aim of this study was to assess the frequency and prognostic implications of a second incident arrhythmia in hospitalized COVID-19 patients over the pandemic course till vaccine availability. Methods: The multicenter COVID-RHYTHM Registry enrolled hospitalized COVID-19 patients from 3/8/2020 to 1/24/2021. Cardiac arrhythmia included documented atrial fibrillation (AF), atrial flutter (AFL), ventricular tachycardia (VT), severe sinus bradycardia (<40 bpm) or AV block. Outcomes were compared between patients with single vs. more than one incident arrhythmias adjusting for baseline variables. Results: Of 6299 hospitalized COVID-19 patients, 4398 had an had an incident cardiac arrhythmia during hospitalization, of which 822 (19%) had a second incident arrhythmia. Those with >1 incident arrhythmia had a higher baseline prevalence of heart failure, chronic kidney disease, coronary artery disease and sleep apnea (Table). Those with >1 incident arrhythmia had higher in-hospital mortality, need for ICU admission and need for rehab upon discharge. Length of stay was similar between the groups. Conclusions: In hospitalized COVID-19 patients with incident cardiac arrhythmias, a second incident arrhythmia during hospitalization was seen in 19%. Having >1 incident arrhythmia was associated with increased need for ICU admission and reduced survival.

Background: Pulsed field ablation uses electrical pulses to cause nonthermal irreversible electroporation and induce cardiac cell death. Pulsed field ablation may have effectiveness comparable to traditional catheter ablation while preventing thermally mediated complications. Methods: The PULSED AF pivotal study (Pulsed Field Ablation to Irreversibly Electroporate Tissue and Treat AF) was a prospective, global, multicenter, nonrandomized, paired single-arm study in which patients with paroxysmal (n=150) or persistent (n=150) symptomatic atrial fibrillation (AF) refractory to class I or III antiarrhythmic drugs were treated with pulsed field ablation. All patients were monitored for 1 year using weekly and symptomatic transtelephonic monitoring; 3-, 6-, and 12-month ECGs; and 6- and 12-month 24-hour Holter monitoring. The primary effectiveness end point was freedom from a composite of acute procedural failure, arrhythmia recurrence, or antiarrhythmic escalation through 12 months, excluding a 3-month blanking period to allow recovery from the procedure. The primary safety end point was freedom from a composite of serious procedure- and device-related adverse events. Kaplan-Meier methods were used to evaluate the primary end points. Results: Pulsed field ablation was shown to be effective at 1 year in 66.2% (95% CI, 57.9 to 73.2) of patients with paroxysmal AF and 55.1% (95% CI, 46.7 to 62.7) of patients with persistent AF. The primary safety end point occurred in 1 patient (0.7%; 95% CI, 0.1 to 4.6) in both the paroxysmal and persistent AF cohorts. Conclusions: PULSED AF demonstrated a low rate of primary safety adverse events (0.7%) and provided effectiveness consistent with established ablation technologies using a novel irreversible electroporation energy to treat patients with AF. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT04198701.