Patterns of comorbidities in patients with atrial fibrillation and impact on management and long-term prognosis: an analysis from the Prospective Global GLORIA-AF Registry.

BACKGROUND: Clinical complexity, as the interaction between ageing, frailty, multimorbidity and polypharmacy, is an increasing concern in patients with AF. There remains uncertainty regarding how combinations of comorbidities influence management and prognosis of patients with atrial fibrillation (AF). We aimed to identify phenotypes of AF patients according to comorbidities and to assess associations between comorbidity patterns, drug use and risk of major outcomes. METHODS: From the prospective GLORIA-AF Registry, we performed a latent class analysis based on 18 diseases, encompassing cardiovascular, metabolic, respiratory and other conditions; we then analysed the association between phenotypes of patients and (i) treatments received and (ii) the risk of major outcomes. Primary outcome was the composite of all-cause death and major adverse cardiovascular events (MACE). Secondary exploratory outcomes were also analysed. RESULTS: 32,560 AF patients (mean age 70.0 ± 10.5 years, 45.4% females) were included. We identified 6 phenotypes: (i) low complexity (39.2% of patients); (ii) cardiovascular (CV) risk factors (28.2%); (iii) atherosclerotic (10.2%); (iv) thromboembolic (8.1%); (v) cardiometabolic (7.6%) and (vi) high complexity (6.6%). Higher use of oral anticoagulants was found in more complex groups, with highest magnitude observed for the cardiometabolic and high complexity phenotypes (odds ratio and 95% confidence interval CI): 1.76 [1.49-2.09] and 1.57 [1.35-1.81], respectively); similar results were observed for beta-blockers and verapamil or diltiazem. We found higher risk of the primary outcome in all phenotypes, except the CV risk factor one, with highest risk observed for the cardiometabolic and high complexity groups (hazard ratio and 95%CI: 1.37 [1.13-1.67] and 1.47 [1.24-1.75], respectively). CONCLUSIONS: Comorbidities influence management and long-term prognosis of patients with AF. Patients with complex phenotypes may require comprehensive and holistic approaches to improve their prognosis.

Atrial fibrillation: stroke prevention.

Stroke prevention is central to the management of patients with atrial fibrillation (AF) which has moved towards a more holistic or integrative care approach. The published evidence suggests that management of AF patients following such a holistic approach based on the Atrial fibrillation Better Care (ABC) pathway is associated with a lower risk of stroke and adverse events. Risk assessment, re-assessment and use of direct oral anticoagulants (DOACs) are important for stroke prevention in AF. The stroke and bleeding risks of AF patients are not static and should be re-assessed regularly. Bleeding risk assessment is to address and mitigate modifiable bleeding risk factors, and to identify high bleeding risk patients for early review and follow-up. Well-controlled comorbidities and healthy lifestyles also play an important role to achieve a better clinical outcome. Digital health solutions are increasingly relevant in the diagnosis and management of patients with AF, with the potential to improve stroke prevention. In this review, we provide an update on stroke prevention in AF, including importance of holistic management, risk assessment/re-assessment, and stroke prevention for special AF populations. Evidence-based and structured management of AF patients would reduce the risk of stroke and other adverse events.

Risk of Incident Atrial Fibrillation and Subsequent Use of Oral Anticoagulants in Patients with Dementia.

BACKGROUND: Dementia and atrial fibrillation (AF) have many shared risk factors. Besides, patients with dementia are under-represented in randomized trials, and even if AF is present, oral anticoagulants (OACs) are not prescribed frequently. This study aimed to report the incidence of newly diagnosed AF in dementia patients, and the impacts of use of vitamin K antagonist (VKA; e.g., warfarin) and non-VKA OAC (NOACs) on stroke and bleeding outcomes. METHODS: Our study utilized the Taiwan National Health Insurance Research Database. A total of 554,074 patients with dementia were compared with 554,074 age- and sex-matched patients without dementia regarding the risk of incident AF. Among patients with dementia who experienced incident AF, the risks of clinical events of patients treated with warfarin or NOACs were compared with those without OACs (reference group). RESULTS: The risk of incident AF was greater for patients with dementia compared with those without (adjusted hazard ratio [aHR]: 1.054; 95% confidence interval [CI]: 1.040-1.068 for all types of dementia, aHR: 1.035; 95% CI: 1.020-1.051 for presenile/senile dementia, and aHR: 1.125; 95% CI: 1.091-1.159 for vascular dementia). Among patients with dementia and experienced incident AF, warfarin use was associated with a higher risk of ischemic stroke (aHR: 1.290; 95% CI: 1.156-1.440), intracranial hemorrhage (ICH; aHR: 1.678; 95% CI: 1.346-2.090), and major bleeding (aHR: 1.192; 95% CI: 1.073-1.323) compared with non-OACs. NOAC use was associated with a lower risk of ischemic stroke (aHR: 0.421; 95% CI: 0.352-0.503) and composite risk of ischemic stroke or major bleeding (aHR: 0.544; 95% CI: 0.487-0.608) compared with non-OACs. These results were consistent among the patients after the propensity matching. CONCLUSION: In this large nationwide cohort, the risk of newly diagnosed AF was higher in patients with dementia (all dementia, presenile/senile dementia, and vascular dementia) compared with those without dementia. For patients with dementia who experienced incident AF, NOAC use was associated with a better clinical outcome compared with non-OAC. Patients with dementia require a holistic approach to their care and management, including the use of NOACs to reduce the risks of clinical events.

Characterization and identification of atrial fibrillation drivers in patients with nonparoxysmal atrial fibrillation using simultaneous amplitude frequency electrogram transform.

INSTRUCTION: We hypothesized that real-time simultaneous amplitude frequency electrogram transform (SAFE-T) during sinus rhythm (SR) is able to identify and characterize the drivers of atrial fibrillation (AF) in nonparoxysmal (NP) AF. METHODS: Twenty-one NPAF patients (85.71% males, mean age 52 years old) underwent substrate mapping during SR (SAFE-T and voltage) and during AF (complex fractionated atrial electrograms [CFAE] and similarity index [SI]). After pulmonary veins isolation, extensive substrate ablation was performed with the endpoint of procedural termination or elimination of all SI sites (>63% similarities). Sites with procedural termination and non-termination sites were tagged for postablation SR analysis using SAFE-T. RESULTS: In 74 CFAE sites identified (average of 3 ± 2 sites per person), 28 (37.84%) were identified as termination sites demonstrating a high SI compared with the non-termination sites (80.11 ± 9.57% vs. 45.96 ± 13.38%, p < .001) during AF. During SR, these termination sites have high SAFE-T values and harbor a highly resonant, localized, repetitive high frequency components superimposed in the low frequency components compared with non-termination sites (5.70 ± 3.04 vs. 1.49 ± 1.66 Hz·mV, p < .001). In the multivariate analysis, the termination sites have higher SAFE-T and SI value (p < .001). CONCLUSION: AF procedural termination sites harbored signal characteristics of repetitive, high frequency component of individualized electrogram during SR, which can be masked by the low frequency fractionated electrogram and are difficult to see from the bipolar electrogram. Thus, SAFE-T mapping is feasible in identifying and characterizing sites of AF drivers.

Stroke prevention in atrial fibrillation.

Atrial fibrillation (AF) is the commonest sustained cardiac rhythm disorder associated with an increased risk of stroke and systemic embolic events. The prevention of stroke using oral anticoagulants has been a pivotal component of AF management. The purpose of this review is to summarize recent advances in the treatment and prevention of stroke in AF over the last 5 years. We performed a comprehensive structured literature search using MEDLINE for publications from 11th March 2015 through to 31st December 2020. We focused mainly on primarily published research articles and systematic reviews including updates in different international guidelines. We found that improved awareness and detection of AF and use of clinical risk stratification are central to the identification of patients at risk of stroke who would benefit from oral anticoagulation. The recommendation of non-vitamin K antagonist oral anticoagulants over warfarin in both efficacy and safety perspective is represented in all international guidelines. Beyond stroke prevention, there is a move to more holistic or integrated care management of AF, which has been shown to improve outcomes. We conclude that stroke prevention remains a dominant part of the management of patients with AF. Not all stroke risk factors carry equal weight, and many require additional scrutiny (e.g. severity of CAD, type of diabetes, duration of hypertension). The utilization of clinical risk scores to help decision-making should take into account that these scores are mere simplification tools to aid decision-making and the additional clinical benefit with more complex risk scores and addition of biomarkers is limited. Also, stroke and bleeding risks are dynamic and require regular review. Instead of arbitrarily categorizing patients into (artificial) low, moderate, and high stroke risk strata, anticoagulation should be offered to all patients with AF unless they are low risk with no risk factors for stroke. Stroke prevention is also part of the proactive, integrated care approach to holistic management of patients with AF, which can be simplified in the ABC (Atrial fibrillation Better Care) pathway: 'A' Avoid stroke/Anticoagulation; 'B' Better symptom management emphasising patient-centred symptom directed decisions on rate or rhythm control strategies; and 'C' refers to Cardiovascular risk and comorbidity optimization, including lifestyle changes and attention to patient values and preferences, as well as the psychological morbidity associated with AF.

2021 Focused Update Consensus Guidelines of the Asia Pacific Heart Rhythm Society on Stroke Prevention in Atrial Fibrillation: Executive Summary.

The consensus of the Asia Pacific Heart Rhythm Society (APHRS) on stroke prevention in atrial fibrillation (AF) has been published in 2017 which provided useful clinical guidance for cardiologists, neurologists, geriatricians, and general practitioners in the Asia-Pacific region. In these years, many important new data regarding stroke prevention in AF were reported. The practice guidelines subcommittee members comprehensively reviewed updated information on stroke prevention in AF, and summarized them in this 2021 focused update of the 2017 consensus guidelines of the APHRS on stroke prevention in AF. We highlighted and focused on several issues, including the importance of the AF Better Care pathway, the advantages of non-vitamin K antagonist oral anticoagulants (NOACs) for Asians, the considerations of use of NOACs for Asian AF patients with single one stroke risk factor beyond gender, the role of lifestyle factors on stroke risk, the use of oral anticoagulants during the "coronavirus disease 2019" pandemic, etc. We fully realize that there are gaps, unaddressed questions, and many areas of uncertainty and debate in the current knowledge of AF, and the physician's decision remains the most important factor in the management of AF.

Low voltage zones detected by omnipolar Vmax map accurately identifies the potential atrial substrate and predicts the AF ablation outcome after PV isolation.

INTRODUCTION: The presence of bipolar low-voltage zone (LVZ) is a predictor of AF recurrence after PV isolation (PVI). However, changes of wavefront and bipole directions may cause different electrogram characteristics. We aimed to investigate whether using omnipolar maximum voltage (Vmax) map derived from high density (HD) Grid mapping catheter could assess LVZ and AF ablation outcome accurately. METHODS: Fifty paroxysmal AF patients (27 males, 57.8 ± 9.5 years old) who underwent 3D mapping guided PVI were enrolled. Left atrial voltage mapping during sinus rhythm before ablation was performed. The significant LVZ (<0.5 mV with area > 5 cm2) were defined as sites by omnipolar Vmax, bipolar HD wave map, conventional bipolar electrograms acquired from electrode pairs along to and across to the catheter shaft. The primary end point was the first documented recurrence of any AF during follow-ups. RESULTS: PVI was performed in all patients, and there were 2 patients (4%) who also received additional non-PV triggers ablation. After a follow-up of 11.4 ± 5.4 months, recurrence of AF occurred in 12 patients (24%). The presence of a significant LVZ was less detected by omnipolar Vmax map, compared to HD wave map (24.0% vs. 58.0%, p = 0.001). LVZ detected by omnipolar Vmax map independently predicted the AF recurrence (odds ratio 16.91; 95% CI, 3.17-90.10; p = 0.001). CONCLUSION: LVZ detected by omnipolar Vmax map accurately predicts the AF recurrence following ablation in paroxysmal AF, compared to conventional bipolar and HD wave maps, suggesting the omnipolar Vmax map can precisely define the atrial substrate property.

Mortality associated with the use of non-vitamin K antagonist oral anticoagulants in cancer patients: Dabigatran versus rivaroxaban.

OBJECTIVE: This study assesses the mortality outcomes of non-vitamin K antagonist oral anticoagulants (NOACs) in cancer patients with venous thromboembolism (VTE) and atrial fibrillation (AF). METHODS: Medical records of cancer patients receiving NOACs for VTE or AF between January 1, 2011, and December 31, 2016, were retrieved from Taiwan's National Health Institute Research Database. NOACs were compared using the inverse probability of treatment weighting (IPTW) method. The primary outcome was cancer-related death. Secondary outcomes were all-cause mortality, major bleeding, and gastrointestinal (GI) bleeding. RESULTS: Among 202,754 patients who received anticoagulants, 3591 patients (dabigatran: 907; rivaroxaban: 2684) with active cancers were studied. Patients who received dabigatran were associated with lower risks of cancer-related death at one year (HR = 0.71, 95% CI = 0.54-0.93) and at the end of follow-ups (HR = 0.79, 95% CI = 0.64-0.98) compared with rivaroxaban. Patients who received dabigatran were also associated with lower risks of all-cause mortality (HR = 0.81, 95% CI = 0.67-0.97), major bleeding (HR = 0.64, 95% CI = 0.47-0.88), and GI bleeding (HR = 0.57, 95% CI = 0.39-0.84) at the end of follow-ups compared with rivaroxaban. CONCLUSION: Compared with rivaroxaban, the use of dabigatran may be associated with a lower risk of cancer-related death and all-cause mortality.

Distribution of triggers foci and outcomes of catheter ablation in atrial fibrillation patients in different age groups.

BACKGROUND: Atrial fibrillation (AF) prevalence increases with age. Aging affects the substrate properties of the left atrium (LA) and the outcomes of catheter ablation for treating AF. We investigated the AF trigger distribution and catheter ablation outcomes in patients of different ages with AF. METHODS: 1585 patients with AF (1181 paroxysmal and 404 non- paroxysmal AF) who had undergone catheter ablation were enrolled. The patients were divided into young (20-40 year-old, n = 175), middle-aged (41-64 year-old, n = 1134), and old (≥ 65 year-old, n = 276) groups. Electrophysiological characteristics and AF trigger sites were recorded. RESULT: The incidence of AF with only non-pulmonary vein (non-PV) foci was higher in the young group than in the other groups (8.6% vs. 3.6% vs. 3.3%, p < 0.01). Non-PV foci were more commonly located in the superior vena cava (SVC) in the young group than in the other groups (13.1% vs. 7.8% vs. 6.5%, p = 0.03). The left atrium (LA) mean voltage was higher and the incidence of very late recurrence after AF ablation was lower in the young group than in the other groups. However, the final AF recurrence rate after multiple procedures and complication rates were similar among all the groups at a mean follow-up of 5.6 years. CONCLUSION: The young patients with AF had a higher incidence of only non-PV foci, mostly located in SVC, than the middle-aged and old patients. Our study highlights the importance of identifying the non-PV foci in catheter ablation of young patients with AF.

The isthmus characteristics of scar-related macroreentrant atrial tachycardia in patients with and without cardiac surgery.

INTRODUCTION: Identifying the critical isthmus (CI) in scar-related macroreentrant atrial tachycardia (AT) is challenging, especially for patients with cardiac surgery. We aimed to investigate the electrophysiological characteristics of scar-related macroreentrant ATs in patients with and without cardiac surgery. METHODS: A prospective study of 31 patients (mean age 59.4 ± 9.81 years old) with scar-related macroreentrant ATs were enrolled for investigation of substrate properties. Patients were categorized into the nonsurgery (n = 18) and surgery group (n = 13). The CIs were defined by concealed entrainment, conduction velocity less than 0.3 m/s, and the presence of local fractionated electrograms. RESULTS: Among the 31 patients, a total of 65 reentrant circuits and 76 CIs were identified on the coherent map. The scar in the surgical group is larger than the nonsurgical group (18.81 ± 9.22 vs. 10.23 ± 5.34%, p = .016). The CIs in surgical group have longer CI length (15.27 ± 4.89 vs. 11.20 ± 2.96 mm, p = .004), slower conduction velocity (0.46 ± 0.19 vs. 0.69 ± 0.14 m/s, p < .001), and longer total activation time (45.34 ± 9.04 vs. 38.24 ± 8.41%, p = .016) than those in the nonsurgical group. After ablation, 93.54% of patients remained in sinus rhythm during a follow-up of 182 ± 19 days. CONCLUSION: The characteristics of the isthmus in macroreentrant AT are diverse, especially for surgical scar-related AT. The identification of CIs can facilitate the successful ablation of scar-related ATs.

Identification of critical isthmus using coherent mapping in patients with scar-related atrial tachycardia.

INTRODUCTION: Accurate identification of slow conducting regions in patients with scar-related atrial tachycardia (AT) is difficult using conventional electrogram annotation for cardiac electroanatomic mapping (EAM). Estimating delays between neighboring mapping sites is a potential option for activation map computation. We describe our initial experience with CARTO 3 Coherent Mapping (Biosense Webster Inc,) in the ablation of complex ATs. METHODS: Twenty patients (58 ± 10 y/o, 15 males) with complex ATs were included. We created three-dimensional EAMs using CARTO 3 system with CONFIDENSE and a high-resolution mapping catheter (Biosense Webster Inc). Local activation time and coherent maps were used to aid in the identification of conduction isthmus (CI) and focal origin sites. System-defined slow or nonconducting zones and CI, defined by concealed entrainment (postpacing interval < 20 ms), CV < 0.3 m/s and local fractionated electrograms were evaluated. RESULTS: Twenty-six complex ATs were mapped (mean: 1.3 ± 0.7 maps/pt; 4 focal, 22 isthmus-dependent). Coherent mapping was better in identifying CI/breakout sites where ablation terminated the tachycardia (96.2% vs 69.2%; P = .010) and identified significantly more CI (mean/chamber 2.0 ± 1.1 vs 1.0 ± 0.7; P < .001) with narrower width (19.8 ± 10.5 vs 43.0 ± 23.9 mm; P < .001) than conventional mapping. Ablation at origin and CI sites was successful in 25 (96.2%) with long-term recurrence in 25%. CONCLUSIONS: Coherent mapping with conduction velocity vectors derived from adjacent mapping sites significantly improved the identification of CI sites in scar-related ATs with isthmus-dependent re-entry better than conventional mapping. It may be used in conjunction with conventional mapping strategies to facilitate recognition of slow conduction areas and critical sites that are important targets of ablation.

Low-Dose Rivaroxaban and Risks of Adverse Events in Patients With Atrial Fibrillation.

Background and Purpose- In the daily practice, low-dose nonvitamin K antagonist oral anticoagulants are commonly used among Asian patients with atrial fibrillation (AF). The aim of the present study was to compare the risks of ischemic stroke, intracranial hemorrhage, and net clinical benefit of Asian patients with AF treated with off-label low-dose and on-label dosing rivaroxaban. Methods- A total of 2214 patients with AF aged ≥20 years treated with rivaroxaban at a tertiary medical center in Taiwan were studied. Patients were categorized into 2 groups: (1) on-label dose (n=1630): ROCKET-AF or J-ROCKET dosage criteria; and (2) off-label low-dose (10 mg/d for patients with an estimated glomerulus filtration rate >50 mL/min, n=584). The risks of ischemic stroke and intracranial hemorrhage were compared between 2 groups. Results- Compared with the on-label dose group, off-label low-dose rivaroxaban was associated with an increased risk of ischemic stroke with an adjusted hazard ratio of 2.75; 95% CI =1.62-4.69; P<0.001). The risk intracranial hemorrhage did not differ significantly between the on-label and off-label low-dosing groups (adjusted hazard ratio =0.62; 95% CI =0.32-1.20; P=0.213). Compared with off-label low-dose group, on-label dosing rivaroxaban was associated with a positive net clinical benefit in different weighted models. The results were consistent among the propensity-matched cohort. Conclusions- Off-label low-dosing rivaroxaban should be avoided for Asian patients with AF giving the higher risk of ischemic stroke without risk reduction in intracranial hemorrhage compared with on-label dosing.

Effectiveness and Safety of Four Direct Oral Anticoagulants in Asian Patients With Nonvalvular Atrial Fibrillation.

BACKGROUND: Whether four direct oral anticoagulants (DOACs) are superior to warfarin in Asian patients with nonvalvular atrial fibrillation (NVAF) remains unclear. METHODS: This nationwide retrospective cohort study was based on data from Taiwan's National Health Insurance Research Database from June 1, 2012, to December 31, 2017, covering patients with NVAF taking edoxaban (n = 4,577), apixaban (n = 9,952), rivaroxaban (n = 33,022), dabigatran (n = 22,371), and warfarin (n = 19,761). Propensity score weighting was used to balance covariates across study groups. Patients were followed up until occurrence of study outcomes or end date of study. RESULTS: Edoxaban, apixaban, and rivaroxaban were associated with a lower risk of ischemic stroke/systemic embolism than warfarin. All DOACs had a lower risk of major bleeding than warfarin. Apixaban was associated with a lower risk of major bleeding than rivaroxaban and dabigatran, whereas the risk of major bleeding was comparable between edoxaban and apixaban. The reduced risks of thromboembolism/major bleeding for the four DOACs persisted in high-risk subgroups, including those with chronic kidney disease, elderly patients (age ≥ 75 years), secondary stroke prevention, or CHA2DS2-VASc score (congestive heart failure, hypertension, age ≥ 75 years, diabetes mellitus, previous stroke/transient ischemic attack, vascular disease, age 65-74 years, and female sex) ≥ 4. A total of 2,924 (64%), 6,359 (64%), 31,108 (94%), and 19,821 (89%) patients received low-dose edoxaban (15-30 mg/d), apixaban (2.5 mg bid), rivaroxaban (10-15 mg/d), and dabigatran (110 mg bid), respectively. The effectiveness/safety outcomes with the four low-dose DOACs compared with warfarin were consistent with the main analysis. CONCLUSIONS: In the largest real-world practice study among Asian patients with NVAF, four DOACs were associated with a comparable or lower risk of thromboembolism, and a lower risk of bleeding than warfarin. There was consistency even among high-risk subgroups and whether standard-or low-dose regimens were compared.

Comparison of phase mapping and electrogram-based driver mapping for catheter ablation in atrial fibrillation.

INTRODUCTION: Adjunctive driver-guided ablation in addition to pulmonary vein isolation has been proposed as a strategy to improve procedural success and outcomes for various populations with atrial fibrillation (AF). First, this study aimed to evaluate the different mapping techniques for driver/rotor identification and second to evaluate the benefits of driver/rotor-guided ablation in patients with paroxysmal and persistent AF (PerAF). METHODS: We searched the electronic database in PubMed using the keywords "atrial fibrillation," "rotor," "rotational driver," "atrial fibrillation source," and "drivers" for both randomized controlled trials and observational controlled trials. Clinical studies reporting efficacy or safety outcomes of driver-guided ablation for paroxysmal AF or (PerAF) were identified. We performed subgroup analyses comparing different driver mapping methods in patients with PerAF. The odds ratios (ORs) with random effects were analyzed. RESULTS: Out of 175 published articles, seven met the inclusion criteria, of which two were randomized controlled trials, one was quasiexperimental study, and four observational studies (three case-controlled studies and one cross-sectional study). Overall, adjunctive driver-guided ablation was associated with higher rates of acute AF termination (OR: 4.62, 95% confidence interval [CI]: 2.12-10.08; P < 0.001), lower recurrence of any atrial arrhythmia (OR: 0.44, 95% CI: 0.30-0.065; P < 0.001), and comparable complication incidence. CONCLUSIONS: Adjunctive driver-guided catheter ablation suggested an increased freedom from AF/AT relative to conventional strategies, irrespective of the mapping techniques. Furthermore, phase mapping appears to be superior to electrogram-based driver mapping in PerAF ablation.

High-resolution mapping of pulmonary vein potentials improved the successful pulmonary vein isolation using small electrodes and inter-electrode spacing catheter.

BACKGROUND: Intracardiac electrogram recording is influenced by the electrode size and inter-electrode spacing. Smaller electrodes with a closer inter-electrode spacing may improve the mapping resolution and outcome. METHODS: Substrate mapping of the left atrium and residual pulmonary vein (PV) potentials during sinus rhythm was sequentially performed using a 3.5-mm electrode tip catheter and a 1-mm electrode multielectrode catheter in 33 patients (Group 1) that underwent repeat atrial fibrillation (AF) procedures. PV gap identification and electrophysiological characteristics were compared. Arrhythmia freedom was compared with a propensity matched (1:2) control group (66 patients, Group 2) undergoing repeat AF procedures guided by wide inter-electrode spacing catheter. RESULTS: In the Group 1 patients, the total area of residual PV potentials measured using the 1-mm catheter was larger than that measured by the 3.5-mm catheter. Overall 1.97 ±â€¯0.59 (1-3) and 1.49 ±â€¯0.62 (1-3) PVs were identified by the 1-mm electrode and 3.5 mm catheters, respectively (P = 0.02). The gaps not identified by the 3.5 mm catheter had a smaller width and lower voltage. Radiofrequency catheter ablation in the areas with residual PV potentials identified by the 1-mm catheter resulted in complete electrical isolation of the PVs. Arrhythmia freedom at one year of follow-up was achieved in 26 of 33 (78.8%) patients in Group 1, which was significantly higher than the matched control group (33/66 [50%], P < 0.05). CONCLUSION: In the patients with a previous PV isolation, mapping with small, closely spaced electrodes can increase the detection rate of residual PV potentials and improve the outcome.

Cigarette smoking causes a worse long-term outcome in persistent atrial fibrillation following catheter ablation.

INTRODUCTION: Cigarette smoking contributes to the development of atrial fibrosis via nicotine. The impact of smoking on ablation results in persistent atrial fibrillation (AF) is unknown. We aimed to investigate the triggers and long-term outcome between smokers and nonsmokers in the patients with persistent AF after catheter ablation. METHODS: This study included 201 (177 males, 53 ± 10 years old) patients who received index catheter ablation, including pulmonary vein isolation (PVI) and complex fractionated atrial electrograms (CFAEs) ablation for persistent AF, retrospectively. Electrophysiological characteristics at the index procedure and long-term outcome were investigated to determine the differences between smokers and nonsmokers. RESULTS: Baseline characteristics were similar between two groups. Pulmonary vein (PV) triggers were found in all patients in the two groups. There was a higher incidence of nonpulmonary vein (NPV) triggers in smokers than in nonsmokers (61% vs. 31%, P < 0.05). There were no differences of the long-term ablation outcomes between smokers and nonsmokers in Kaplan-Meier analysis. Smokers with PV plus right atrial NPV (RA-NPV) triggers had a higher incidence of recurrence (log-rank P < 0.05) than those without RA-NPV triggers, but not in nonsmokers, after a mean follow-up of 31 ± 25 months. CONCLUSIONS: Smoking increases the incidence of NPV triggers in patients with persistent AF. Smokers who have RA-NPV triggers during index procedure do have a worse outcome after catheter ablation, indicating the harmful effects of nicotine to right atrium.

Novel electrophysiological criteria for septal ventricular outflow tract tachycardias requiring a sequential bilateral ablation.

BACKGROUND: Septal ventricular outflow tract ventricular arrhythmias (OT-VAs) are defined as septal origin VAs from the right ventricular or left ventricular OT. Patients with septal OT-VAs may require a sequential bilateral OT ablation. This study aimed to evaluate the electrophysiological characteristics and ablation outcome in patients with septal OT-VAs. METHODS: We retrospectively analyzed the electrocardiography and electrophysiological parameters in 96 patients (mean age 49 ± 15 years, 49 male) undergoing bilateral activation mapping before catheter ablation of idiopathic septal OT-VAs. The patients were categorized into three groups based on the successful ablation sites, including the right ventricular outflow tract (RVOT), RVOT/left ventricular outflow tract (LVOT), and LVOT. RESULTS: Mapping in the three groups demonstrated a gradually decreasing and increasing trend in the earliest activation time obtained from the RVOT and LVOT, respectively. The absolute earliest activation time discrepancy (AEAD) of ≤18 milliseconds could predict the requirement for a sequential bilateral ablation with a sensitivity and specificity of 100.0% and 93.7%, respectively. The small AEAD (≤21 milliseconds) was associated with a higher recurrence rate in patients receiving a successful unilateral ablation, while patients with a longer distance between the bilateral OT earliest activation sites (DEA > 26 mm) increased future recurrences after an initially successful sequential bilateral ablation. CONCLUSIONS: The application of bilateral OT-VA activation mapping and the measurement of the AEAD and DEA provided not only pivotal information for the ablation strategy, but also prognostic implications for recurrences in patients with septal OT-VAs.

Lifetime Risks, Projected Numbers, and Adverse Outcomes in Asian Patients With Atrial Fibrillation: A Report From the Taiwan Nationwide AF Cohort Study.

BACKGROUND: Most data on the clinical epidemiology of atrial fibrillation (AF) come from Western populations, and data for Asians are limited. We investigated the lifetime risk and projected number of AF among Asians. The annual risks of adverse events among patients with AF, time trends, and the risks compared with patients without AF were analyzed. METHODS: Between 2000 and 2011, 289,559 patients aged ≥ 20 years experienced new-onset AF in Taiwan. The incidence, prevalence, and lifetime risk of AF were calculated. The risk of adverse events among patients with AF were analyzed and compared with that of age- and sex-matched patients without AF. RESULTS: The incidence of AF in year 2011 was 1.51 per 1,000 person-years, with a lifetime risk of AF being appropriately 1 in 7 for subjects aged > 20 years. The prevalence of AF is estimated to be 4.01% in 2050. Compared with patients without AF, AF was associated with an increased risk of mortality (adjusted hazard ratio [aHR], 2.61), heart failure (aHR, 3.31), ischemic stroke (aHR, 3.34), dementia (aHR, 1.56), sudden cardiac death (aHR, 1.83), and myocardial infarction (aHR, 1.62); all P < .01. The risks of ischemic stroke, heart failure, and mortality were especially higher compared with patients without AF in the initial period (approximately 6 months) after AF was first diagnosed. CONCLUSIONS: The burden of AF among Asian patients is increasing, with a lifetime risk of AF being 1 in 7. Optimized management of any associated comorbidities should be part of the holistic management approach for AF.