Outcomes of ventricular tachycardia ablation in patients with ischemic and non-ischemic cardiomyopathy: A propensity-score matched analysis.

INTRODUCTION AND OBJECTIVES: Catheter ablation (CA) is effective in the treatment of ventricular tachycardia (VT). Although some observational data suggest patients with non-ischemic cardiomyopathy (NICM) have less favorable outcomes when compared to those with an ischemic etiology (ICM), direct comparisons are rarely reported. We aimed to compare the outcomes of VT ablation in a propensity-score matched population of ICM or NICM patients. METHODS: Single-center retrospective study of consecutive patients undergoing VT ablation from 2012 to 2023. A propensity score (PS) was used to match ICM and NICM patients in a 1:1 fashion according to age, sex, left ventricular ejection fraction (LVEF), NYHA class, electrical storm (ES) at presentation, and previous endocardial ablation. The outcomes of interest were VT-free survival and all-cause mortality. RESULTS: The PS yielded two groups of 71 patients each (mean age 63±10 years, 92% male, mean LVEF 35±10%, 36% with ES at presentation, and 23% with previous ablation), well matched for baseline characteristics. During a median follow-up of 2.3 (interquartile range IQR 1.3-3.8) years, patients with NICM had a significantly lower VT-free survival (53.5% vs. 69.0%, log-rank p=0.037), although there were no differences regarding all-cause mortality (22.5% vs. 16.9%, log-rank p=0.245). Multivariate analysis identified NICM (HR 2.34 [95% CI 1.32-4.14], p=0.004), NYHA class III/IV (HR 2.11 [95% CI 1.11-4.04], p=0.024), and chronic kidney disease (HR 2.23 [95% CI 1.25-3.96], p=0.006), as independent predictors of VT recurrence. CONCLUSION: Non-ischemic cardiomyopathy patients were at increased risk of VT recurrence after ablation, although long-term mortality did not differ.

Coronary atherosclerotic burden in veteran athletes: The relationship between cardiovascular risk and volume of exercise.

INTRODUCTION AND OBJECTIVES: The association between exercise and coronary atherosclerosis still remains unclarified. We aimed to analyze the prevalence of high coronary atherosclerotic burden in veteran athletes, considering cardiovascular (CV) risk and volume of exercise. METHODS: A total of 105 asymptomatic male veteran athletes (48±5.6 years old) were studied. A high coronary atherosclerotic burden was defined as one of the following characteristics in coronary computed tomography angiography: calcium score >100, >75th percentile, obstructive plaques, involving left main, three-vessels or two-vessels including proximal anterior descending artery, segment involvement score >5 or CT-adapted Leaman score ≥5. CV risk was stratified by SCORE2 and volume of exercise by metabolic equivalent task score. RESULTS: Most athletes (n=88) were engaged in endurance sports for 17.1±9.8 years, with a median exercise volume of 66 [IQR 44-103] metabolic equivalent of tasks/hour/week. The mean Systematic Coronary Risk Evaluation 2 was 2.8±1.5%; 76.9% of athletes had a low-moderate risk and none a very high risk. High coronary atherosclerotic burden was present in 25.7% athletes. Athletes with high cardiovascular risk and high exercise volume (above the median) showed significantly high coronary atherosclerotic burden compared to those with low-moderate risk and high volume (50.0% vs. 15.6%; p=0.017). Among athletes with low to moderate risk, a high volume of exercise tended to be protective, while in those with low volume, there was similar rate of high coronary atherosclerotic burden, regardless of CV risk. CONCLUSIONS: A combination of higher volume of exercise and high cardiovascular risk revealed the worst association with coronary atherosclerosis in veteran athletes. The relationship between these variables is controversial, but integrating exercise characteristics and risk assessment into preparticipation evaluation is essential.

Quality indicators in atrial fibrillation ablation (RIQAFA). A national registry from the Portuguese Association of Arrhythmology, Pacing and Electrophysiology (APAPE).

INTRODUCTION AND OBJECTIVES: Atrial fibrillation (AF) is the most common sustained arrhythmia, with significant burden for patients. Catheter ablation is safe and superior for symptom improvement. The purpose of this work was to assess how clinical practice compares with current scientific evidence and quality indicators for AF ablation. METHODS: The Portuguese Association of Arrhythmology, Pacing and Electrophysiology conducted a prospective registry among Portuguese centers to assess clinical practice regarding management of patients referred for ablation and the methodology used in the procedures and related outcomes. RESULTS: A total of 337 patients were referred for ablation, 102 (37.91%) female, age 65 (56-70.8) years. The median CHADS2-VaSC2 thromboembolic risk score was 2 (1-3), and 308 (92.49%) were on anticoagulants. AF was mainly paroxysmal (224, 66.97%) and symptomatic (mEHRA score 3; 2-3). Before ablation most patients (273, 81.49%) underwent cardiac computed tomography and only 24 (7.36%) procedures were performed with uninterrupted anticoagulation. For ablation, Carto® (194; 59.15%) and Ensite® (55; 16.77%) were mainly used, and the preferential strategy was pulmonary vein isolation (316; 94.61%). Acute complications occurred in five (1.49%) patients, while most had symptom improvement at one month (200; 86.21%), sustained at one year. There were 40 (12.6%) relapses within 30 days and 19 (26.39%) at one year. CONCLUSIONS: In a population of patients with AF referred for ablation in Portuguese centers, patient management is provided according to the best scientific evidence and there is a high standard of practice with respect to the quality of AF ablation practice.

EHRA expert consensus document on the management of arrhythmias in frailty syndrome, endorsed by the Heart Rhythm Society (HRS), Asia Pacific Heart Rhythm Society (APHRS), Latin America Heart Rhythm Society (LAHRS), and Cardiac Arrhythmia Society of Southern Africa (CASSA).

There is an increasing proportion of the general population surviving to old age with significant chronic disease, multi-morbidity, and disability. The prevalence of pre-frail state and frailty syndrome increases exponentially with advancing age and is associated with greater morbidity, disability, hospitalization, institutionalization, mortality, and health care resource use. Frailty represents a global problem, making early identification, evaluation, and treatment to prevent the cascade of events leading from functional decline to disability and death, one of the challenges of geriatric and general medicine. Cardiac arrhythmias are common in advancing age, chronic illness, and frailty and include a broad spectrum of rhythm and conduction abnormalities. However, no systematic studies or recommendations on the management of arrhythmias are available specifically for the elderly and frail population, and the uptake of many effective antiarrhythmic therapies in these patients remains the slowest. This European Heart Rhythm Association (EHRA) consensus document focuses on the biology of frailty, common comorbidities, and methods of assessing frailty, in respect to a specific issue of arrhythmias and conduction disease, provide evidence base advice on the management of arrhythmias in patients with frailty syndrome, and identifies knowledge gaps and directions for future research.

Independent factors of low radiation dose during atrial fibrillation ablation with cryoballoon or radiofrequency: Results from the "Go for zero fluoroscopy" registry.

AIMS: Atrial fibrillation (AF) catheter ablation is a common procedure requiring in most cases the use of fluoroscopy. We aimed to evaluate the factors associated with a lower dose of fluoroscopy used during AF ablation with cryoballoon or radiofrequency. METHODS: In this prospective European registry, centers were requested to provide procedural characteristics of consecutive AF ablation cases. Lower doses of fluoroscopy were defined as those with dose-area-product (DAP) under the median dose used in the radiofrequency and the cryoballoon ablation groups. RESULTS: A total of 638 AF ablation procedures were collected (n = 492 for radiofrequency and n = 146 for cryoballoon ablation groups) in 25 centers. The median [IQR] DAP were 926 [349;2092] and 1516 [418;3408] cGy*cm2 in the radiofrequency and cryoballoon groups, respectively. Main factors associated with lower DAP in cryoballoon ablation group were electrophysiology dedicated laboratory (OR 6.04, 95%CI 1.16-31.54; P = .03) and frequent dosimetry report (OR 21.39, 95%CI 5.43-98.54; P = .03). Main factors associated with lower DAP in the radiofrequency ablation group were the use of a chest dosimeter (OR 12.57, 95% CI 2.88-54.90; P = .01), biplane X-ray equipment (OR 3.12, 95%CI 1.89-5.16; P < .01), university hospital (OR 2.10, 95%CI 1.35-3.25; P = .01), electrophysiology dedicated laboratory (OR 2.45, 95%CI 1.48-4.05; P < .01) and use of contact force enabled catheter (OR 22.60, 95%CI 6.82-74.88; P < .01). CONCLUSION: This real-life study of fluoroscopy use during AF ablation provides new data about current practices across European countries. Technological advances and quality of the fluoroscopic environment were the main factors associated with lower radiation dose during AF ablation.

Portuguese National Registry on Cardiac Electrophysiology, 2017 and 2018. / Registo Nacional de Eletrofisiologia Cardíaca 2017­2018.

INTRODUCTION: The authors present the results of the national cardiac electrophysiology registry of the Portuguese Association of Arrhythmology, Pacing and Electrophysiology (APAPE) and the Portuguese Institute of Cardiac Rhythm (IPRC) for 2017 and 2018. METHODS: The registry is annual, voluntary, and observational. Data are collected retrospectively. Developments over the years and their implications are analyzed and discussed. RESULTS: In the 22 electrophysiology centers, 3407 ablations were performed in 2017 and 3653 ablations in 2018. Atrial fibrillation (AF) ablation was the most frequently performed procedure: 1017 ablations in 2017 and 1222 procedures in 2018. Of the patients undergoing AF ablation, 63% were male, 60% were between 50 and 69 years old and 74% had paroxysmal AF. Clinically relevant complications were reported in 0.8% of the procedures. In 2017, 216 ventricular tachycardia (VT) ablation procedures were performed in 15 centers. In 2018, 19 centers performed 249 VT ablations. About 45% of VT ablations were performed in patients with structural heart disease. Complications were reported in 3.2% of the procedures, including one death (0.2%). CONCLUSIONS: The national electrophysiology registry showed a sustained increase in the number of catheter ablations. In addition, procedural complexity increased and AF ablation assumed a dominant position among the procedures performed.

Development and validation of a risk score for predicting atrial fibrillation recurrence after a first catheter ablation procedure - ATLAS score.

Aims: Several predictors of relapse after catheter ablation of atrial fibrillation (AF) have been established, but assessing each patient's individual risk remains challenging. Our aim was to develop and validate a score to estimate the risk of AF recurrence after the first radiofrequency pulmonary vein isolation (PVI) procedure. Methods and results: Independent predictors of AF relapse were identified retrospectively in a two-centre registry of 1934 patients who underwent a first PVI procedure. Using the Cox regression hazard ratios of designated variables, a risk score was developed in a random sample of 50% of the patients (development cohort) and validated in the remaining (validation cohort) half. The accuracy and discriminative power of the predictive model were assessed in both subgroups. During a follow-up of 4.2 ± 2.7 years, 522 patients (27%) relapsed. Five independent predictors of AF recurrence were identified and included in the score: age >60 years (1 point), female sex (4 points), non-paroxysmal AF (2 points), current smoking (7 points) and indexed left atrial volume (1 point for each 10 mL/m2). The score showed good discriminative power (censored c-statistic of 0.75 in both cohorts). In the development group, AF relapse rates were 8, 11, and 17%/year for low (<6 points), intermediate (6-10 points), and high-risk patients (>10 points), respectively (P < 0.001). In the validation group, AF recurrence rates were 8, 11, and 18%/year, respectively (P < 0.001). Conclusion: A simple risk score to estimate the rate of AF recurrence after ablation was developed and validated. An external assessment of its usefulness as a patient selection tool seems warranted.

Brugada syndrome is associated with scar and endocardial involvement: Insights from high-density mapping with the Rhythmia™ mapping system.

The authors report the first catheter ablation of Brugada syndrome in the literature using the Rhythmia™ mapping system. Learning points include: (1) low voltage areas can be documented while mapping in some individuals, suggesting that Brugada syndrome may not be a pure ion channel disorder; (2) typical long fractionated potentials can also be identified in the endocardium, supporting the need to map the endocardium in all Brugada patients requiring ablation; (3) disappearance of the typical coved pattern following ablation does not necessarily predict cure, as the patient we present experienced ventricular fibrillation recurrence a few months later.

Variability in interpretation of the electrocardiogram in athletes: Another limitation in pre-competitive screening. / Variabilidade na interpretação do eletrocardiograma do atleta: mais uma limitação na avaliação pré­competitiva.

INTRODUCTION: Assessment of the electrocardiogram (ECG) in athletes remains controversial, with lack of standardization and difficulty in applying specific criteria in its interpretation. The purpose of this study was to assess variability in the interpretation of the ECG in athletes. METHODS: Twenty ECGs of competitive athletes were assessed by cardiologists and cardiology residents, 11 of them normal or with isolated physiological changes and nine pathological. Each ECG was classified as normal/physiological or pathological, with or without the use of specific interpretation criteria. RESULTS: The study presents responses from 58 physicians, 42 (72.4%) of them cardiologists. Sixteen (27.6%) physicians reported that they regularly assessed athletes and 32 (55.2%) did not use specific ECG interpretation criteria, of which the Seattle criteria were the most commonly used (n=13). Each physician interpreted 15±2 ECGs correctly, corresponding to 74% of the total number of ECGs (variation: 45%-100%). Interpretation of pathological ECGs was correct in 68% (variation: 22%-100%) and of normal/physiological in 79% (variation: 55%-100%). There was no significant difference in interpretation between cardiologists and residents (74±10% vs. 75±10%; p=0.724) or between those who regularly assessed athletes and those who did not (77±12% vs. 73±9%; p=0.286), but there was a trend for a higher rate of correct interpretation using specific criteria (77±10% vs. 72±10%; p=0.092). The reproducibility of the study was excellent (intraclass correlation coefficient=0.972; p<0.001). CONCLUSIONS: A quarter of the ECGs were not correctly assessed and variability in interpretation was high. The use of specific criteria can improve the accuracy of interpretation of athletes' ECGs, which is an important part of pre-competitive screening, but one that is underused.

Low previous cardiovascular risk of patients with ST-elevation myocardial infarction.

BACKGROUND: Myocardial infarction is frequently the initial form of presentation of coronary artery disease (CAD). Systemic Coronary Risk Estimation (SCORE) risk tables are used in primary prevention and provide an estimate of cardiovascular (CV) risk through known risk factors. The aim of this study was to evaluate the performance of the SCORE, calculated using data previous to the event, to estimate CV risk of a population of patients presenting with ST-elevation myocardial infarction (STEMI) as the first manifestation of CAD. METHODS AND RESULTS: From a prospective registry including 3056 patients with STEMI subjected to coronary angiography between 2004 and 2014, 1628 patients with STEMI as the first manifestation of CAD were included after the exclusion of patients with known CAD (n=748, 24.5%), patients with high-risk equivalents (n=930, 30.4%), and patients with normal coronaries (n=57, 1.87%). The individual risk profile was calculated using data previous to the event and patients were classified into three established subgroups: low risk (SCORE<5%; n=1162, 71.4%), high risk (SCORE 5-10%; n=409, 25.1%), and very high risk (SCORE≥10%; n=57, 3.5%). CONCLUSION: In a population of patients with STEMI as the first manifestation of CAD, the CV risk stratification with the SCORE risk charts, if calculated before the event, would classify as low risk more than two-thirds of the patients (71.4%) and only 3.5% would be classified as very high-risk patients. The high prevalence of low-risk patients indicates the current challenge of CV risk stratification, underlying the need for additional tools in primary prevention to better identify patients at risk.

Relationship between rotors and complex fractionated electrograms in atrial fibrillation using a novel computational analysis.

INTRODUCTION: Rotors and complex fractionated atrial electrograms (CFAEs) have been suggested as possible therapeutic targets in ablation of atrial fibrillation (AF). The aim of this study was to assess the relationship between rotors and CFAEs in patients with AF. METHODS: We studied 18 patients with AF (mean age 69±8 years, 33% female) who underwent rotor ablation and pulmonary vein isolation. Endocardial mapping was performed with a basket catheter to identify the presence, number and location of rotors and CFAEs. The FIRM™ (Abbott) and CARTO™ (Biosense) systems were used with overlapping of frames from continuous 30-s recordings. CFAEs were classified as stable if present in >15 frames, moderately stable if present in 10-15 frames and unstable if present in 5-9 frames. RESULTS: A total of 44 rotors and 60 CFAEs (39 of them stable) were identified. The mean number of rotors and stable CFAEs per patient was 2.6±1.4 and 2.2±1.5, respectively. In 27 of the 44 identified rotors, CFAEs were found in the same location. Conversely, in 20 of the 39 stable CFAEs identified, a focal rotor was found in the same location. The majority of CFAEs found at the same location as a focal rotor were stable (63% vs. 37%, p=0.001). CONCLUSION: Rotors and CFAEs are frequently found in the same location within the atria, particularly when only stable CFAEs are considered. This relationship may have implications in the selection of substrate targets for ablation.

Dabigatran in real-world atrial fibrillation. Meta-analysis of observational comparison studies with vitamin K antagonists.

In the RE-LY clinical trial, dabigatran presented a better effectiveness/safety profile when compared to warfarin. However, clinical trials are not very representative of the real-world setting. We aimed to assess the performance of dabigatran in real-world patients with atrial fibrillation (AF) by means of a systematic review and meta-analysis of observational comparison studies with vitamin K antagonists (VKA). We searched PubMed, Embase and Scopus databases until November 2015 and selected studies according to the following criteria: observational study performed with nonvalvular AF patients; reporting adjusted hazard ratios (HR) of clinical events in a follow-up period; for dabigatran 75 mg, 110 mg or 150 mg versus VKA. Twenty studies were selected which included 711,298 patients, 210,279 of which were treated with dabigatran and the remaining 501,019 with VKA. Ischaemic stroke incidence was of 1.65 /100 patient-years for dabigatran and 2.85/100 patient-years for VKA (HR 0.86, 95 % confidence interval of 0.74-0.99). Major bleeding rate was 3.93/100 patient-years for dabigatran and 5.61/100 patient-years for VKA (0.79, 0.69-0.89). Risk of mortality (0.73, 0.61-0.87) and intracranial bleeding (0.45, 0.38-0.52) were significantly lower in patients treated with dabigatran when compared to patients on VKA. Risk of gastrointestinal (GI) bleeding was significantly higher in patients treated with dabigatran (1.13, 1.00-1.28). No significant difference was observed in risk of myocardial infarction (0.99, 0.89-1.11). In this combined analysis of real-world observational comparison studies with VKA, dabigatran was associated with a lower risk of ischaemic stroke, major bleeding, intracranial bleeding and mortality, higher risk of GI bleeding and a similar risk of myocardial infarction.

Long-term prognosis of patients with Brugada syndrome and an implanted cardioverter-defibrillator.

INTRODUCTION: Risk stratification of Brugada syndrome (BrS) remains controversial and recommendations for an implantable cardioverter-defibrillator (ICD) are not well established. The objective of this study was to assess the long-term prognosis of BrS patients with an ICD. METHODS AND RESULTS: Of 55 consecutive patients with BrS assessed between April 2002 and October 2012, 36 (mean age 41.7 ± 13.8 years; 81.8% male) underwent ICD implantation. Nineteen (52.8%) were asymptomatic, 11 (30.6%) had previous history of syncope (arrhythmic cause suspected in eight) and six (16.7%) had aborted sudden cardiac death (SCD). Spontaneous type 1 electrocardiographic (ECG) pattern was present in 25 (69.4%) patients and electrophysiological study (EPS), performed in 26 (72.2%), was positive in 22 (84.6%). During a mean follow-up of 74 ± 40 months (>5 years in 72% of cases), seven (19.4%) patients had appropriate shocks (annual event rate 2.8%). These patients most frequently had aborted SCD (54.1% vs. 6.9%; p=0.008) and nonsustained ventricular tachycardia (57.1% vs. 10.3%; p=0.016) during follow-up. Spontaneous type 1 ECG pattern, syncope and positive EPS were not significantly associated with appropriate shocks. Multivariate analysis revealed that aborted SCD was an independent predictor of appropriate shocks (HR 8.07, 95% CI 1.58-41.2; p=0.012). ROC curve analysis demonstrated that aborted SCD had moderate discriminatory power to predict appropriate shocks (AUC 0.751), with sensitivity of 57% and specificity of 93%. In terms of ICD-related complications, eight (22.2%) patients had inappropriate shocks during the follow-up period, mainly due to sinus tachycardia (five patients); one patient had lead infection and another had a lead fracture. CONCLUSION: In this population of BrS patients with ICD, the long-term rate of appropriate shocks was 2.8%/year. Aborted SCD was associated with a higher risk of appropriate shocks, whereas syncope and spontaneous type I ECG pattern did not predict this event.