Clinical relevance of the blanking period on late recurrence after catheter ablation of atrial fibrillation.

INTRODUCTION: Recurrence of atrial fibrillation (AF) within the blanking period after catheter ablation (CA) is traditionally classified as a transient and benign event. However, recent findings suggest that early recurrence (ER) is associated with late recurrence (LR), challenging the predefined "blanking period". We aimed to determine the clinical and procedural predictors of ER and LR after CA and establish the risk of LR in patients who experience ER. METHODS AND RESULTS: Retrospective single-centre study including all patients who underwent a first procedure of AF CA between 2017 and 2019. ER was defined as any recurrence of AF, atrial flutter or atrial tachycardia >30 s within 90 days after CA and LR as any recurrence after 90 days of CA. A total of 399 patients were included, 37% women, median age of 58 years [49-66] and 77% had paroxysmal AF. Median follow-up was 33 months (from 13 to 61). ER after CA was present in 14% of the patients, and LR was reported in 32%. Among patients who experienced ER, 84% also had LR (p < .001). Patients with ER had a higher prevalence of moderate/severe valvular heart disease, persistent AF, previous electrical cardioversion, a larger left atrium, higher coronary artery calcium score, and higher rates of intraprocedural electrical cardioversion and cardiac fibrosis on eletroanatomical mapping compared with patients without ER. After covariate adjustment, ER and female sex were defined as independent predictors of LR (hazard ratio [HR] 4.69; 95% confidence interval [CI], 2.99-7.35; p < .001 and HR 2.73; 95% CI, 1.47-5.10; p = .002, respectively). CONCLUSION: The risk of LR after an index procedure of CA was significantly higher in patients with ER (five-fold increased risk). These results support the imperative need to clarify the clinical role of the blanking period.

Ostial vs. wide area circumferential ablation guided by the Ablation Index in paroxysmal atrial fibrillation.

AIMS: Pulmonary vein isolation (PVI) guided by the Ablation Index (AI) has shown high acute and mid-term efficacy in the treatment of paroxysmal atrial fibrillation (AF). Previous data before the AI-era had suggested that wide-area circumferential ablation (WACA) was preferable to ostial ablation. However, with the use of AI, we hypothesize that ostial circumferential ablation is non-inferior to WACA and can improve outcomes in paroxysmal AF. METHODS AND RESULTS: Prospective, multicentre, non-randomized, non-inferiority study of consecutive patients were referred for paroxysmal AF ablation from January 2020 to September 2021. All procedures were performed using the AI software, and patients were separated into two different groups: WACA vs. ostial circumferential ablation. Acute reconnection, procedural data, and 1-year arrhythmia recurrence were assessed. During the enrolment period, 162 patients (64% males, mean age of 60 ± 11 years) fulfilled the study inclusion criteria-81 patients [304 pulmonary vein (PV)] in the WACA group and 81 patients (301 PV) in the ostial group. Acute PV reconnection was identified in 7.9% [95% confidence interval (CI), 4.9-11.1%] of PVs in the WACA group compared with 3.3% (95% CI, 1.8-6.1%) of PVs in the ostial group [P < 0.001 for non-inferiority; adjusted odds ratio 0.51 (95% CI, 0.23-0.83), P = 0.05]. Patients in the WACA group had longer ablation (35 vs. 29 min, P = 0.001) and procedure (121 vs. 102 min, P < 0.001) times. No significant difference in arrhythmia recurrence was seen at 1-year of follow-up [11.1% in WACA vs. 9.9% in ostial, hazard ratio 1.13 (95% CI, 0.44-1.94), P = 0.80 for superiority]. CONCLUSION: In paroxysmal AF patients treated with tailored AI-guided PVI, ostial circumferential ablation is not inferior to WACA with regard to acute PV reconnection, while allowing quicker procedures with less ablation time.

Impact of Coronary Artery Calcium Score Screening on Cardiovascular Risk Stratification of Patients with Atrial Fibrillation Undergoing Ablation.

INTRODUCTION: There is a well-established association between atrial fibrillation (AF) and coronary artery disease. Coronary artery calcium score (CACS) is a helpful tool to refine cardiovascular (CV) risk stratification and inform on the best strategies for primary CV prevention. This study aims to evaluate the impact of opportunistic screening with CACS on risk stratification and decision of preventive therapies, in patients with AF. METHODS: Cross-sectional study including patients with AF or atrial flutter undergoing cardiac computed tomography for ablation procedure planning, from 2017 to 2019. Baseline clinical and demographical data were collected. CACS was assessed in patients without coronary artery disease using the Agatston method. RESULTS: A total of 474 patients were included (93% with AF, mean age of 58 ± 10 years, 62% male). CACS >0 was present in 254 (54%) patients. According to CACS and the Society of Cardiovascular Computed Tomography recommendations, 25% of the patients would be candidates for statin therapy and 17% would be candidates for changes in the current statin intensity; in 11 patients (8%), acetylsalicylic acid would be recommended. CONCLUSION: In our study, more than half of the patients undergoing cardiac computed tomography before AF catheter ablation had CACS above zero. Our findings suggest that an opportunistic evaluation of CACS at the time of ablation can be an important tool to improve CV risk stratification, with important clinical and therapeutic implications.

Assessment of the need of a waiting period after pulmonary vein isolation with the ablation index software.

PURPOSE: Since the widespread availability of contact-force sensing catheters, the need for a waiting period after pulmonary vein isolation (PVI) has not been reassessed. We aim to evaluate whether a waiting period is still necessary after PVI guided by the ablation Index (AI). METHODS: Prospective, multicenter, randomized study of consecutive patients referred for paroxysmal atrial fibrillation (AF) ablation from May 2019 to February 2020. Patients were randomized in a 1:1 ratio to PVI with versus without a waiting period of 20 min. Acute pulmonary vein (PV) reconnection after adenosine challenge was the primary endpoint. A per-protocol analysis was designed to determine whether a strategy of dismissing the waiting period after PVI was noninferior to waiting for 20 min for identifying acute PV reconnection. PVI was guided by tailored AI values and an interlesion distance ≤6 mm. RESULTS: During the enrollment period, 167 patients (56% males, mean age of 57 ± 14 years) fulfilled the study inclusion criteria - 84 patients (308 PV) in the waiting period group (Group A) and 83 patients (314 PV) in the group without a waiting period (Group B). Acute PV reconnection was identified in 3.8% (95% confidence interval [CI], 1.7%-5.9%) of PVs in the study group B compared to 2.9% (95% CI, 1.0%-4.8%) of PVs in the Group A (p = .002 for non-inferiority). At 1-year follow-up, there was no significant difference in arrhythmia recurrence between groups (9.5% in Group A vs. 9.6% in Group B, hazard ratio: 1.03 [95% CI, 0.39-2.73], p = .98). CONCLUSION: In paroxysmal AF patients submitted to ablation, a tailored PVI guided by the AI rendered a 20-min waiting period unnecessary.

Safety, efficacy, and reproducibility of cavotricuspid isthmus ablation guided by the ablation index: acute results of the FLAI study.

AIMS: Ablation index (AI) is a marker of lesion quality during catheter ablation that incorporates contact force, time, and power in a weighted formula. This index was originally developed for pulmonary vein isolation as well as other left atrial procedures. The aim of our study is to evaluate the feasibility and efficacy of the AI for the ablation of the cavotricuspid isthmus (CTI) in patients presenting with typical atrial flutter (AFL). METHODS AND RESULTS: This prospective multicentre non-randomized study enrolled 412 consecutive patients with typical AFL undergoing AI-guided cavotricuspid isthmus ablation. The procedure was performed targeting an AI of 500 and an inter-lesion distance measurement of ≤6 mm. The primary endpoints were CTI 'first-pass' block and persistent block after a 20-min waiting time. Secondary endpoints included procedural and radiofrequency duration and fluoroscopic time. A total of 412 consecutive patients were enrolled in 31 centres (mean age 64.9 ± 9.8; 72.1% males and 27.7% with structural heart disease). The CTI bidirectional 'first-pass' block was reached in 355 patients (88.3%), whereas CTI block at the end of the waiting time was achieved in 405 patients (98.3%). Mean procedural, radiofrequency, and fluoroscopic time were 56.5 ± 28.1, 7.8 ± 4.8, and 1.9 ± 4.8 min, respectively. There were no major procedural complications. There was no significant inter-operator variability in the ability to achieve any of the primary endpoints. CONCLUSION: AI-guided ablation with an inter-lesion distance ≤6 mm represents an effective, safe, and highly reproducible strategy to achieve bidirectional block in the treatment of typical AFL.

Early Repolarization Pattern and Left Ventricular Mass in Hypertrophic Cardiomyopathy.

BACKGROUND: J-point elevation in the inferior and/or lateral leads is associated with an increased incidence of sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM), although the exact underlying mechanism is not known. As severe left ventricular hypertrophy and late gadolinium enhancement (LGE) are important risk factors for SCD in this population, we aimed to assess whether there was an association between an early repolarization pattern (ERP) and greater left ventricular mass (LVM) and LGE extent among patients with HCM. METHODS: This was a retrospective cohort study of 85 consecutive patients with HCM who underwent cardiac magnetic resonance (CMR) and had an electrocardiogram without confounders (intraventricular conduction delay, complete left or right bundle branch block, or ventricular paced rhythm). Baseline characteristics and MRI-derived LVM and LGE extent were compared between patients with and without ERP. RESULTS: ERP was present in 9 out of 85 patients (10.6%). Patients with ERP had greater indexed LVM compared to those without (112.5 ± 26.3 vs. 87.8 ± 24.6 g/m2, p = 0.006). Logistic regression analysis revealed a 4.2-fold increase in the odds of prevalent ERP per standard deviation increase in body surface area-indexed LVM (odds ratio 4.2; 95% CI 1.54-11.4, p = 0.005). There were no statistically significant differences regarding LGE extent between groups. CONCLUSION: ERP is associated with greater CMR-derived LVM among patients with HCM. This finding could partially explain the association between J waves and a higher risk of SCD in this population. There were no differences in LGE extent. Further studies are needed to confirm this association and evaluate the importance of ERP as a marker of increased risk of SCD in HCM.

Differential Impact of a Cardiac Rehabilitation Program on Functional Parameters in Elderly versus Non-Elderly Myocardial Infarction Survivors.

BACKGROUND: Exercise-based cardiac rehabilitation (EBCR) plays a pivotal role in the management of acute myocardial infarction (AMI). Studies have shown that older individuals have a worse prognosis after an AMI, attesting to the importance of risk reduction strategies. We aimed at assessing the impact of age (patients dichotomized as ≥65 years old or <65 years old) on the functional benefits of an EBCR program among AMI survivors. DESIGN: Observational, retrospective cohort study. PARTICIPANTS: All patients admitted due to an AMI who completed a phase II EBCR program after discharge, between November 2012 and April 2017. INTERVENTION: EBCR program. MEASUREMENTS: Functional parameters were assessed by a symptom-limited cardiopulmonary exercise test. RESULTS: A total of 379 patients were included (30% aged ≥65 years). After the EBCR program, peak oxygen uptake (pVO2) and exercise duration increased significantly. Patients aged ≥65 years presented with more comorbidities and a lower functional capacity. Those aged ≥65 years presented significantly smaller improvements in pVO2 (0.79 ± 2.61 vs. 1.60 ± 3.11 mL/kg/min, p = 0.016) and exercise duration [75 (59-120) vs. 120 s (60-180), p = 0.002]. This was maintained after adjusting for several potential confounders. CONCLUSION: Older patients have a worse functional capacity than their younger counterparts. Still, a contemporary EBCR program was associated with significant functional improvements among those aged ≥65 years. The smaller improvements even after adjustments for potential confounders suggest that physiological differences may contribute to this finding. These results highlight the relevance of EBCR among this higher-risk subgroup.

Complete atrioventricular block during exercise: New insights from an old test.

Exercise stress testing can have a central role in the assessment of cardiovascular disease. Contemporary data, however, has highlighted the added value of imaging modalities over the exercise electrocardiogram in the investigation of coronary artery disease. Given the physiological changes associated with exercise and the possibility to address other parameters such as rhythm changes and the chronotropic response, exercise stress testing with continuous electrocardiographic monitoring can still have an important place in contemporary clinical practice. We report the case of a complete atrioventricular block associated with exercise and discuss the current role of exercise stress testing with continuous electrocardiographic monitoring in this entity.

A devices' game of thrones: cardiac resynchronization therapy vs. pacemaker.

AIMS: Oversensing can interfere with biventricular pacing. Cardiac Resynchronization Therapy (CRT) output inhibition due to automatic brady mode change from a sensing to a pacing mode of a previously implanted pacemaker as it reached battery capacity depleted indicator has not been previously published in the medical literature. METHODS AND RESULTS: We report the first case of CRT output inhibition in a pacemaker dependent patient due to electrical stimuli from a previously right-sided implanted pacemaker, after unaware reversion of OVO mode (O = no chambers paced; V = ventricular sensing; O = no response to sensing) to backup VVI (V = ventricular pacing; V = ventricular sensing; I = inhibitory response to sensing) when it reached the elective replacement interval. CONCLUSION: This paper emphasizes the importance of knowing the distinct pacemaker brady mode behaviours after battery capacity depleted indicator has been reached, according to the pacemakers' manufacturer, including the possibility of automatic brady mode change from sensing to pacing mode. It also highlights the potential for severe bradycardia or asystole of this automatic brady mode change from a previously implanted pacemaker in pacemaker dependent patients submitted to CRT upgrade.

Can Pre-Ablation Biomarkers Be Used to Predict Arrhythmia Recurrence after Ablation Index-Guided Atrial Fibrillation Ablation? / Os Biomarcadores podem ser Utilizados para Prever Recorrência de Arritmia após a Ablação de Fibrilação Atrial Guiada pelo Ablation-Index?

BACKGROUND: Ablation Index (AI) software has allowed better atrial fibrillation (AF) ablation results, but recurrence rates remain significant. Specific serum biomarkers have been associated with this recurrence. OBJECTIVES: To evaluate whether certain biomarkers could be used (either individually or combined) to predict arrhythmia recurrence after AI-guided AF ablation. METHODS: Prospective multicenter observational study of consecutive patients referred for AF ablation from January 2018 to March 2021. Hemoglobin, brain natriuretic peptide (BNP), C-reactive protein, high sensitivity cardiac troponin I, creatinine clearance, thyroid-stimulating hormone (TSH) and free thyroxine (FT4) were assessed for their ability to predict arrhythmia recurrence during follow-up. Statistical significance was accepted for p values of<0.05. RESULTS: A total of 593 patients were included - 412 patients with paroxysmal AF and 181 with persistent AF. After a mean follow-up of 24±6 months, overall single-procedure freedom from atrial arrhythmia was 76.4%. Individually, all biomarkers had no or only modest predictive power for recurrence. However, a TSH value >1.8 µUI/mL (HR=1.82 [95% CI, 1.89-2.80], p=0.006) was an independent predictor of arrhythmia recurrence. When assessing TSH, FT4 and BNP values in combination, each additional "abnormal" biomarker value was associated with a lower freedom from arrhythmia recurrence (87.1 % for no biomarker vs. 83.5% for one vs. 75.1% for two vs. 43.3% for three biomarkers, p<0.001). Patients with three "abnormal" biomarkers had a threefold higher risk of AF recurrence compared with no "abnormal" biomarker (HR=2.88 [95% CI, 1.39-5.17], p=0.003). CONCLUSIONS: When used in combination, abnormal TSH, FT4 and BNP values can be a useful tool for predicting arrhythmia recurrence after AI-guided AF ablation.

FUNDAMENTO: O software ablation index (AI) permitiu melhorar os resultados da ablação de fibrilação atrial (FA), mas as taxas de recorrência permanecem significativas. Biomarcadores séricos específicos têm sido associados a essa recorrência. OBJETIVOS: Avaliar se certos biomarcadores podem ser utilizados (individualmente ou combinados) para predizer a recorrência de FA pós ablação guiada pelo AI. MÉTODOS: Estudo multicêntrico, observacional, prospectivo de pacientes consecutivos, encaminhados para ablação de FA de janeiro de 2018 a março de 2021. Hemoglobina, peptídeo natriurético cerebral (BNP), proteína C reativa, troponina I ultrassensível, clearance de creatinina, Hormônio Tireoestimulante (TSH), e Tiroxina livre (T4) foram avaliados quanto à capacidade de prever a recorrência de arritmias durante o acompanhamento. Valores de p <0,05 foram aceitos como estatisticamente significativos. RESULTADOS: Um total de 593 pacientes foram incluídos ­ 412 com FA paroxística e 181 com FA persistente. Durante o seguimento médio de 24±6 meses, 76,4% não apresentaram recidiva após ablação. Individualmente, os biomarcadores demonstraram um valor preditivo baixo ou nulo para recorrência. No entanto, TSH >1,8 µUI/mL [HR=1,82 (IC95%, 1,89-2,80), p=0,006] foi um preditor independente de recorrência. Avaliando-se a combinação de TSH, FT4 e BNP, a adição de cada valor "anormal" foi associada a uma menor sobrevida livre de recorrência (87,1% se nenhum vs. 83,5% se um vs. 75,1% se dois vs. 43,3% se três biomarcadores, p<0,001). Doentes com três biomarcadores "anormais" apresentaram três vezes maior probabilidade de recorrência de FA, comparativamente aos que não apresentaram nenhum biomarcador "anormal" (HR=2,88 [IC95%, 1,39-5,17], p=0,003). CONCLUSÕES: Quando combinados, valores anormais de TSH, FT4 e BNP podem ser uma ferramenta útil para prever a recorrência de FA pós ablação guiada pelo AI.

Sex-based differences and risk of recurrence in patients with atrial fibrillation undergoing pulmonary vein isolation.

INTRODUCTION: Studies suggest increased likelihood of atrial fibrillation (AF) recurrence after catheter ablation (CA) in women than in men, indicating that sex may be an independent risk factor for recurrence. Nevertheless, the influence of sex on AF recurrence and underlying mechanisms remains unclear. METHODS: Retrospective, single-centre study including patients undergoing AF CA between 2017 and 2021. Late recurrence (LR) was defined as AF recurrence ≥90 days after ablation, whereas early recurrence (ER) occurred within 90 days. RESULTS: 656 patients (32% women) were included, with a median follow-up period of 26 months. Compared to men, women undergoing CA were older, had higher body mass indexes, and had higher rates of hypertension, thyroid dysfunction, and valvular disease. Women also had increased LR risk after CA (HR 1.76, 95% CI [1.19, 2.59]). A time-split multivariable analysis at one year of follow-up showed no difference in LR risk during the first 12 months after CA (HR 1.19, 95% CI [0.73, 1.94]); however, LR risk increased in women (HR 2.90, 95% CI [1.68, 5.01]) after 12 months. In a sex-stratified analysis, coronary calcium score (CCS) >100 was associated with increased LR risk in men (HR 1.81, 95% CI [1.06, 3.08]), but not in women. Cardiac adipose tissue volume was not associated with increased LR risk. CONCLUSIONS: Fewer women underwent CA than men and LR was more frequent in women, particularly one year after the procedure. CCS was associated with increased LR risk in men.

Transcatheter aortic valve implantation and requirements of pacing over time.

BACKGROUND: A permanent pacemaker (PPM) implantation is common after transcatheter aortic valve implantation (TAVI). We sought to evaluate requirements of pacing and incidence of pacemaker dependency during the first year after TAVI. METHODS: From August 2007 until May 2011, 65 patients underwent TAVI with self-expandable prosthesis. Five patients paced at baseline and two procedure-related deaths were excluded. Evaluation of ventricular pacing percentage (VP%) and look for spontaneous rhythm were performed at 3, 6, and 12 months. RESULTS: PPM implantation was required in 19/58 patients (33%). Mean VP% decreased between assessments (59% at 3 months, 48% at 6 months, 50% at 12 months), but overall VP% at 1 year was high (57% ± 43%) and most patients were paced ≥10% of time. A favorable annulus-to-aorta angle was associated with lower pacing requirements (60% of patients paced ≤10% of time vs 10% of patients paced >10% of time presented an angle ≤30°, P = 0.039). Pacemaker dependency was established in 27% of patients and could be predicted by the presence of porcelain aorta (odds ratio = 30, confidence interval 95% 1-638, P = 0.029). New postprocedural left bundle branch block (LBBB) had a negative impact on 1-year survival (58% vs 82% in non-LBBB group, P = 0.111). PPM implantation had no impact on 1-year survival. CONCLUSIONS: One third of patients required PPM after TAVI and full recovery of advanced conduction abnormalities seems unlikely. Unfavorable aortic root orientation may hinder the deployment of the valve and contribute to the continued impairment of the conduction system. Porcelain aorta was a strong predictor of pacemaker dependency.

[National registry on cardiac electrophysiology (2010 and 2011)]. / Registo Nacional de Eletrofisiologia Cardíaca (2010 e 2011).

Based on a survey sent to Portuguese centers that perform diagnostic and interventional electrophysiology and/or implant cardioverter-defibrillators (ICDs), the authors analyze the number and type of procedures performed during 2010 and 2011 and compare these data with previous years. In 2011, a total of 2533 diagnostic electrophysiologic procedures were performed, which were followed by ablation in 2013 cases, a steady increase over previous years. The largest share of this increase compared to 2010 was in atrial fibrillation, which is now the second most frequent indication for ablation, after atrioventricular nodal reentrant tachycardia. The total number of ICDs implanted in 2011 was 1084, of which 339 were biventricular (BiV) cardiac resynchronization devices (BiV ICDs). This represents an increase in the total number relative to previous years, 2011 being the first year in which the rate of new ICD implantations in Portugal exceeded 100 per million population. However, compared to 2010, the number of BiV ICDs implanted decreased, despite the recent publication of updated European guidelines on device therapy in heart failure, which clarified and expanded the indications for implantation of these devices. Some comments are made on the current status of cardiac electrophysiology in Portugal and on factors that may influence its development in the coming years.

[Isolated left ventricular non-compaction: a single-center experience]. / Não compactação isolada do ventrículo esquerdo: experiência de um centro.

Isolated left ventricular noncompaction (LVNC) is a rare cardiomyopathy characterized by excessive and prominent trabeculations associated with deep recesses that communicate with the ventricular cavity. Determining the natural history of this condition has been hampered by differences in clinical features and prognosis in published series, which are partly the result of differing diagnostic criteria and the lack of management guidelines. This work aims to contribute to the characterization of isolated LVNC by analyzing an affected population in terms of clinical presentation, diagnosis, risk stratification, treatment and follow-up. We also discuss the most relevant data from the literature concerning this cardiomyopathy.

Epicardial adipose tissue volume is not an independent predictor of atrial fibrillation recurrence after catheter ablation.

INTRODUCTION AND OBJECTIVES: Previous studies have suggested that epicardial adipose tissue (EAT) could exert a paracrine effect in the myocardium. However, few studies have assessed its role in the risk of atrial fibrillation (AF) recurrence. This study aimed to evaluate the association between EAT volume, and its attenuation, with the risk of AF recurrence after AF ablation. METHODS: A total of 350 consecutive patients who underwent AF ablation were included. The median age was 57 [IQR 48-65] years and 21% had persistent AF. Epicardial fat was quantified by multidetector computed tomography using Syngo.via Frontier-Cardiac Risk Assessment software, measuring pericardial fat volume (PATV), EAT volume, and attenuation of EAT posterior to the left atrium. AF recurrence was defined as any documented episode of AF, atrial flutter, or atrial tachycardia more than 3 months after the procedure. RESULTS: After a median follow-up of 34 [range, 12-57] months, 114 patients (33%) had AF recurrence. Univariable Cox regression showed that patients with an EAT volume ≥ 80mL had an increased risk of AF recurrence (HR, 1.65; 95%CI, 1.14-2.39; P=.007). However, after multivariable adjustment, EAT volume did not remain an independent predictor of AF recurrence (HR, 1.24; 95%CI, 0.83-1.87; P=.3). Similar results were observed with PATV. Patients with lower attenuation of EAT did not have a higher risk of AF recurrence (log-rank test, P=.75). CONCLUSIONS: EAT parameters including the evaluation of EAT volume, PATV and EAT attenuation were not independent predictors of AF recurrence after catheter ablation.

Clinical outcome of a single procedure cryoballoon ablation for the treatment of atrial fibrillation: A real-world multicenter experience in Portugal.

BACKGROUND: Cryoballoon ablation (CBA) for pulmonary vein isolation (PVI) has been growing as an alternative technique, not only in patients with paroxysmal atrial fibrillation (PAF) but also in persistent atrial fibrillation (AF). Cryoballoon ablation has demonstrated encouraging acute and mid-term results. However, data on long-term follow-up of CB-based PVI are scarce. OBJECTIVE: We sought to examine efficacy, safety, and long-term outcomes of CBA in PAF and persistent AF in four Portuguese centers. METHODS: All patients that were treated with the cryoballoon catheter according to routine practices with a second-generation 28-mm CB in four centers were included. This was a retrospective, non-randomized analysis. Patients were followed-up for >12 months and freedom from atrial arrhythmias (AA) was evaluated at the end of follow-up. RESULTS: Four hundred and six patients (57.7±12.4 years, 66% men) participated. AF was paroxysmal in 326 patients (80.2%) and persistent in 80 (19.7%). The mean procedure time duration was 107.7±50.9 min, and the fluoroscopy time was 19.5±9.7 min. Procedural/periprocedural complications occurred in 30 cases (7.3%), being transient phrenic nerve palsy the most frequent incident (2 out of 3 complications). Anatomic variations of the PV were present in 16.1% of cases. At a mean follow-up of 22.0±15.0 months, 310 patients (76.3%) remained in stable sinus rhythm, with at least one AF episode recurrence documented in 98 cases (24.1%). The recurrence rate was 20.5% in the PAF group and 37.8% in the persistent AF group. CONCLUSION: In this multicenter experience, a single CBA procedure resulted in 75.9% freedom from AF at a 22-month follow-up. This technique was demonstrated to be a safe and effective option in experienced centers for the treatment of PAF and PersAF.

High-power short-duration versus low-power long-duration ablation guided by the ablation index.

AIMS: To compare the two different ablation strategies, both guided by the Ablation Index (AI), in the setting of atrial fibrillation (AF) ablation: high-power short-duration (HPSD) ablation using 40 W on the posterior wall and 50 W elsewhere versus low-power long-duration (LPLD) using 25 W posteriorly and 35 W elsewhere. METHODS: Prospective, multicenter nonrandomized, noninferiority study of consecutive patients referred for paroxysmal AF ablation from January 2018 to July 2019. Ablation was guided by the AI (≥500 for anterior segments, ≥450 for the roof and inferior segments and 400 posteriorly) and an interlesion distance (ILD) ≤ 6 mm. Patients were separated into two groups: HPSD vs LPLD. Acute reconnection (after adenosine trial) and 2-year outcomes were assessed. RESULTS: 160 patients (61% males, median age of 62 [IQR 51-69] years), fulfilled the study inclusion criteria - 80 patients (316 pulmonary veins [PV]) in the HPSD group and 80 patients (314 PV) in the LPLD. The probability of acute PV reconnection was similar between both groups: 2.2% in HPSD, 95%CI 0.6% to 3.8% vs. 3.4% in LPLD, 95%CI 1.4% to 5.4%; p < 0.001 for noninferiority. Median PV ablation time (20 min vs 30 min, p < 0.01) and procedure duration (80 min vs 100 min, p < 0.001) were shorter in the HPSD group. After a median follow-up of 26 months, arrhythmia recurrence was similar between groups (17.5% in HPSD group vs. 18.8% in LPLD group, p = 0.79). CONCLUSIONS: In paroxysmal AF patients treated with the Ablation Index, a HPSD strategy is noninferior to the more standard LPLD ablation, while allowing for quicker procedures with shorter ablation times.

Higher coronary artery calcium score is associated with increased risk of atrial fibrillation recurrence after catheter ablation.

BACKGROUND: Coronary artery calcium score (CACS) is associated with an increased risk of atrial fibrillation (AF) development, but scarce data are available regarding the impact on AF recurrence. This study aims to assess the impact of CACS on AF recurrence following catheter ablation. METHODS: Retrospective study of patients with AF undergoing cardiac computed tomography (CCT) before ablation (2017-2019). Patients with coronary artery disease (CAD), significant valvular heart disease and previous catheter ablation were excluded. A cut-off of CACS ≥ 100 was used according to literature. RESULTS: A total of 311 patients were included (median age 57 [48, 64] years, 65% men and 21% with persistent AF). More than half of the patients had a CACS > 0 (52%) and 18% a CACS ≥ 100. Patients with CACS ≥ 100 were older (64 [59, 69] vs 55 [46, 63] years, p â€‹< â€‹0.001), had more frequently hypertension (68% vs 42%, p â€‹< â€‹0.001) and diabetes mellitus (21% vs 10%, p â€‹= â€‹0.020). During a median follow-up of 34 months (12-57 months), 98 patients (32%) had AF recurrence. CACS ≥ 100 was associated with increased risk of AF recurrence (unadjusted Cox regression: hazard ratio [HR] 2.0; 95% confidence interval [CI], 1.3-3.1, p â€‹= â€‹0.002). After covariate adjustment, CACS ≥ 100 and persistent AF remained independent predictors of AF recurrence (HR, 1.7; 95% CI, 1.0-2.8, p â€‹= â€‹0.039 and HR, 2.0; 95% CI, 1.3-3.2, p â€‹= â€‹0.004, respectively). CONCLUSION: An opportunistic evaluation of CACS could be an important tool to improve clinical care considering that CACS ≥ 100 was independently associated with a 69% increase in the risk of AF recurrence after first catheter ablation.

Cardioneuroablation for severe neurocardiogenic syncope.

INTRODUCTION AND OBJECTIVES: Cardioneuroablation (CNA), a technique based on radiofrequency ablation of cardiac vagal ganglia, was developed to treat recurrent vasovagal syncope (VVS) with a predominant cardioinhibitory component, as an alternative to pacemaker implantation. The aim of our study was to evaluate the safety and success rate of CNA guided by extracardiac vagal stimulation in patients with highly symptomatic cardioinhibitory VVS. METHODS: Prospective study of patients who underwent anatomically guided CNA at two cardiology centers. All patients had a history of recurrent syncope with a predominant cardioinhibitory component and refractory to conventional measures. Acute success was determined by the absence or significant reduction of cardiac parasympathetic response to extracardiac vagal stimulation. The primary endpoint was the recurrence of syncope during follow-up. RESULTS: In total, 19 patients (13 males; mean age 37.8±12.9 years) were included. Ablation was acutely successful in all patients. One patient had a convulsive episode after the procedure, which was deemed unrelated to the ablation, requiring admission to intensive care but without sequelae. No other complications occurred. At a mean follow-up of 21.0±13.2 months (range 3-42 months), 17 patients remained free of syncope. The remaining two patients had recurrence of syncope and, despite undergoing a new ablation procedure, required pacemaker implantation during follow-up. CONCLUSION: Cardioneuroablation, confirmed by extracardiac vagal stimulation, appears to be an effective and safe treatment option for highly symptomatic patients with refractory VVS with a predominant cardioinhibitory component, providing a new potential approach as an alternative to pacemaker implantation.