Impact of Diagnosis-to-Ablation Time on AF Recurrence: Pronounced the First 3 Years, Irrelevant Thereafter.

BACKGROUND: Diagnosis-to-ablation time (DAT) strongly predicts recurrence of atrial fibrillation (AF) after ablation. Whether this association holds with any lower and/or upper limits is unknown. OBJECTIVES: The goal of this study was to assess the impact of DAT on AF recurrence in search of lower and upper DAT thresholds. METHODS: A total of 2,000 patients with AF from 2 cohorts of 1,000 patients each (69% male; age 62 ± 10 years) undergoing pulmonary vein isolation (PVI) between 2005-2014 and 2017-2019 were followed up for 3 years. RESULTS: Clinical success was achieved in 61.7% of patients. Median DAT decreased over time from 36 months (Q1-Q3: 12-72 months) in the first cohort to 12 months (Q1-Q3: 5-48 months) in the second cohort (P < 0.001). A multivariable Cox proportional hazards fitted model of AF recurrence rate in relation to DAT (range: 0-288 months) showed a steep rise in AF recurrence, from 27% to 40% in the first 36 months (d%/dt = 0.36), with a first inflection point at 36 months, and a less steep rise to 45% until 90 months (d%/dt = 0.09), with flattening beyond 90 months (d%/dt = 0.026). Rise in AF recurrence rate in the first 36 months was higher in patients with persistent AF (from 40% to 54%; d%/dt = 0.39) than in patients with paroxysmal AF (19% to 29%; d%/dt = 0.28). CONCLUSIONS: The association between DAT and AF recurrence has no lower limit ("the shorter the better"), whereas little gain is to be expected beyond 36 months ("the longer the more irrelevant"). Our data advocate for performing PVI as early as possible, certainly within 3 years of AF diagnosis, and even more so in persistent AF.

Cryoballoon ablation for atrial fibrillation in octogenarians: a propensity score-based analysis with a younger cohort.

BACKGROUND: In terms of safety and efficacy, cryoballoon ablation (CB-A) has become a valid option for achieving pulmonary vein isolation (PVI) in patients affected by symptomatic atrial fibrillation. However, CB-A data in octogenarians are still scarce and limited to single-centre experiences. The present multicentre study aimed to compare the outcomes and complications of index CB-A in patients older than 80 years with a cohort of younger patients. METHODS AND RESULTS: We retrospectively enrolled 97 consecutive patients aged ≥80 years who underwent PVI using the second-generation CB-A. This group was compared with a younger cohort of patients using a 1:1 propensity score matching. After the matching, 70 patients from the elderly group were analysed and compared with 70 younger patients (control group). The mean age was 81.4 ±â€Š1.9 years among octogenarians and 65.2 ±â€Š10.2 years in the younger cohort. The global success rate after a median follow-up of 23 [18-32.5] months was 60.0% in the elderly group and 71.4% in the control group (P = 0.17). Phrenic nerve palsy was the most common complication occurring in a total of 11 patients (7.9%): in 6 (8.6%) patients in the elderly group and in 5 patients (7.1%) in the younger group (P = 0.51). Only two (1.4%) major complications occurred: one (1.4%) femoral artery pseudoaneurysm in the control group, which resolved with a tight groin bandage, and one (1.4%) case of urosepsis in the elderly group. Arrhythmia recurrence during the blanking period and the need for electrical cardioversion to restore sinus rhythm after PVI were found to be the only independent predictors of late arrhythmia relapses. CONCLUSIONS: The present study showed that CB-A PVI is as feasible, safe and effective among appropriately selected octogenarians as it is in younger patients.

Ajmaline-Induced Abnormalities in Brugada Syndrome: Evaluation With ECG Imaging.

Background The rate of sudden cardiac death (SCD) in Brugada syndrome (BrS) is ≈1%/y. Noninvasive electrocardiographic imaging is a noninvasive mapping system that has a role in assessing BrS depolarization and repolarization abnormalities. This study aimed to analyze electrocardiographic imaging parameters during ajmaline test (AJT). Methods and Results All consecutive epicardial maps of the right ventricle outflow tract (RVOT-EPI) in BrS with CardioInsight were retrospectively analyzed. (1) RVOT-EPI activation time (RVOT-AT); (2) RVOT-EPI recovery time, and (3) RVOT-EPI activation-recovery interval (RVOT-ARI) were calculated. ∆RVOT-AT, ∆RVOT-EPI recovery time, and ∆RVOT-ARI were defined as the difference in parameters before and after AJT. SCD-BrS patients were defined as individuals presenting a history of aborted SCD. Thirty-nine patients with BrS were retrospectively analyzed and 12 patients (30.8%) were SCD-BrS. After AJT, an increase in both RVOT-AT [105.9 milliseconds versus 65.8 milliseconds, P<0.001] and RVOT-EPI recovery time [403.4 milliseconds versus 365.7 milliseconds, P<0.001] was observed. No changes occurred in RVOT-ARI [297.5 milliseconds versus 299.9 milliseconds, P=0.7]. Before AJT no differences were observed between SCD-BrS and non SCD-BrS in RVOT-AT, RVOT-EPI recovery time, and RVOT-ARI (P=0.9, P=0.91, P=0.86, respectively). Following AJT, SCD-BrS patients showed higher RVOT-AT, higher ∆RVOT-AT, lower RVOT-ARI, and lower ∆RVOT-ARI (P<0.001, P<0.001, P=0.007, P=0.002, respectively). At the univariate logistic regression, predictors of SCD-BrS were the following: RVOT-AT after AJT (specificity: 0.74, sensitivity 1.00, area under the curve 0.92); ∆RVOT-AT (specificity: 0.74, sensitivity 0.92, area under the curve 0.86); RVOT-ARI after AJT (specificity 0.96, sensitivity 0.58, area under the curve 0.79), and ∆RVOT-ARI (specificity 0.85, sensitivity 0.67, area under the curve 0.76). Conclusions Noninvasive electrocardiographic imaging can be useful in evaluating the results of AJT in BrS.

Single procedural outcomes in the setting of percutaneous ablation for persistent atrial fibrillation: a propensity-matched score comparison between different strategies.

BACKGROUND: Catheter ablation for persistent atrial fibrillation (persAF) is associated with less favorable outcomes than for paroxysmal AF. To improve success rates, left atrial (LA) substrate modification is frequently performed in addition to pulmonary vein isolation (PVI). The purpose of the study was to compare 4 different ablation approaches using radiofrequency catheter ablation (RFCA) or cryoballoon ablation (CB-A) for persAF and to evaluate the respective outcomes on a midterm follow-up of 12 months. METHODS: We did a propensity score-matched comparison of 30 patients undergoing PVI + LA posterior wall isolation (LAPWI) with CB-A, 30 patients who underwent PVI + linear ablation (roof and mitral lines) using RFCA, 60 patients with PVI alone using CB-A, and 60 patients who had PVI alone using RFCA. The endpoint was recurrence of documented atrial tachyarrhythmias (ATas) > 30 s at 1-year follow-up. RESULTS: After 12 months, freedom from ATas after a single procedure was 83.3% in the PVI + LAPWI group, 46.7% in the PVI + linear ablation group, 58.3% in the PVI-alone CB-A group, and 61.6% PVI-alone RFCA (p = 0.03). Moreover, freedom from ATas was significantly higher comparing the PVI + LAPWI group with each of the other groups. CONCLUSIONS: In this propensity-matched comparison of strategies for persAF, LAPW ablation in addition to PVI with CB-A seems to improve 1-year outcome in comparison to PVI + linear ablation using RFCA and to PVI alone using RFCA or CB-A. Randomized comparisons are eagerly awaited.

High-density epicardial mapping in Brugada syndrome: Depolarization and repolarization abnormalities.

BACKGROUND: The pathogenesis of Brugada syndrome (BrS) and consequently of abnormal electrograms (aEGMs) found in the epicardium of the right ventricular outflow tract (RVOT-EPI) is controversial. OBJECTIVE: The purpose of this study was to analyze aEGM from high-density RVOT-EPI electroanatomic mapping (EAM). METHODS: All patients undergoing RVOT-EPI EAM with the HD-Grid catheter for BrS were retrospectively included. Maps were acquired before and after ajmaline, and all patients had concomitant noninvasive electrocardiographic imaging with annotation of RVOT-EPI latest activation time (RVOTat). High-frequency potentials (HFPs) were defined as ventricular potentials occurring during or after the far-field ventricular EGM showing a local activation time (HFPat). Low-frequency potentials (LFPs) were defined as aEGMs occurring after near-field ventricular activation showing fractionation or delayed components. Their activation time from surface ECG was defined as LFPat. RESULTS: Fifteen consecutive patients were included in the study. At EAM before ajmaline, 7 patients (46.7%) showed LFPs. All patients showed HFPs before and after ajmaline and LFPs after ajmaline. Mean HFPat (134.4 vs 65.3 ms, P <.001), mean LFPat (224.6 vs 113.6 ms, P <.001), and mean RVOTat (124.8 vs 55.9 ms, P <.001) increased after ajmaline. RVOTat correlated with HFPat before (ρ = 0.76) and after ajmaline (ρ = 0.82), while RVOTat was shorter than LFPat before (P <.001) and after ajmaline (P <.001). BrS patients with history of aborted sudden cardiac death had longer aEGMs after ajmaline. CONCLUSION: Two different types of aEGMs are described from BrS high-density epicardial mapping. This might correlate with depolarization and repolarization abnormalities.

Novel noncontact charge density map in the setting of post-atrial fibrillation atrial tachycardias: first experience with the Acutus SuperMap Algorithm.

PURPOSE: The purpose of this study was to evaluate the safety and feasibility of the new high-resolution mapping algorithm SuperMap (Acutus Medical, CA, USA) in identifying and guiding ablation in the setting of regular atrial tachycardias following index atrial fibrillation (AF) ablation. METHODS: Seven consecutive patients who underwent a radiofrequency catheter ablation guided by the novel noncontact charge density (CD) SuperMap for atrial tachycardia were prospectively enrolled in our study. RESULTS: Arrhythmogenic substrate was identified in all seven patients. Mean number of EGM per map was 5859.7 ± 4348.5 points. Three patients (43%) exhibited focal tachycardia mechanisms in the left atrium, alternating from anteroseptal right superior pulmonary vein (RSPV), posterior in proximity of left inferior pulmonary vein (LIPV), and interarial septum in proximity of fossa ovalis, respectively. Four patients exhibited macroreentrant mechanism. In 3 of these patients, SuperMap detected mitral isthmus-dependent flutters with tachycardia cycle lengths of 240, 270 and 420 ms, respectively. In one patient, the mechanism was a macroreentrant tachycardia with the critical isthmus located between the crista terminalis and atriotomy. The mean ablation time (min) was 18.2 ± 12.5 and the mean procedural duration time was 56.4 ± 12.1 min. No minor or major complications occurred. CONCLUSION: The novel high-resolution mapping algorithm SuperMap proved to be safe, fast, and feasible in identifying and guiding ablation in the setting of regular atrial tachycardias following index AF ablation.

Phrenic nerve palsy during right-sided pulmonary veins cryoapplications: new insights from pulmonary vein anatomy addressed by computed tomography.

PURPOSE: There is still sparse information regarding phrenic nerve palsy (PNP) during the cryoablation of both right-sided pulmonary vein (PV) and its anatomical predictors. METHODS: Consecutive patients who had undergone pulmonary vein isolation (PVI) using CB-A and suffered PNP during both right-sided PVs were retrospectively included in our study. Two other groups were then selected among patients who experienced PNP during RIPV application only (group 2) and RSPV application only (group 3). RESULTS: The incidence of PNI during both right-sided PVs cryoapplications was 2.1%, (32 of 1542 patients). There were no significant clinical differences between the 3 groups. Time from basal temperature to -40 °C significantly differed among the groups for both RIPV (p = 0.0026) and RSPV applications (p = 0.0382). Patients with PNP occurring during RSPV applications had significantly larger RSPV cross-sectional area compared to patients without PNP (p = 0.0116), while in patients with PNP during RIPV application, the angle of RIPV ostium on the transverse plane was significantly smaller compared to patients without PNP (p = 0.0035). The carina width was significantly smaller in patients with PNP occurring during both right-sided PVs cryoapplications compared to patients in which PNP occurred only during one right-sided PV application (p < 0.0001); a cutoff value of 8.5 mm had a sensitivity of 87.3% and a specificity of 75.0%. CONCLUSION: PNP in both right-sided PVs applications is a complication that occurred in 2.1% of cases during CB-A. Pre-procedural evaluation of right PVs anatomy might be useful in evaluating the risk of PNP.