Catheter Ablation for Paroxysmal Atrial Fibrillation With Sick Sinus Syndrome: Insights From the Kansai Plus Atrial Fibrillation Registry.

BACKGROUND: Coexisting sick sinus syndrome (SSS) is associated with both electrical and structural atrial remodelling in patients with atrial fibrillation (AF). Limited data are available concerning catheter ablation (CA) for AF in this condition. This study investigated the efficacy of CA as a curative therapy for AF and SSS in a large-scale prospective multicentre registry. METHODS: The Kansai Plus Atrial Fibrillation (KPAF) registry enrolled 5,010 consecutive patients who underwent CA for AF; this included 3,133 patients with paroxysmal AF (mean age, 66 years; male, 69.3%; mean CHA2DS2-VASc score, 2.05±1.50; SSS, n=315 [tachy-brady syndrome, n=285]). The endpoints included the recurrence of AF with a blanking period of 90 days after CA, and de novo pacemaker implantation during the follow-up period (median duration, 2.93 years). RESULTS: The AF-free survival did not significantly differ between patients with and those without SSS (n=2,818) after the initial (log-rank p=0.864) and final sessions (log-rank p=0.268). Pacemakers were implanted in 48 patients with SSS, and implantation in this group was significantly associated with AF recurrence, including early recurrence (adjusted odds ratio, 3.57; 95% confidence interval, 1.67-7.64; p=0.002). The remaining 85.3% of patients with SSS did not require pacemaker implantation at 3 years after CA. CONCLUSIONS: Coexisting SSS did not adversely affect recurrence-free survival after CA for paroxysmal AF. Pacemaker implantation was not required in most patients with SSS, with AF recurrence serving as a strong predictor for this.

Safety of clinical engineer-assisted percutaneous coronary intervention.

Percutaneous coronary intervention (PCI) requires multiple staff members, including interventional cardiologists, with the physical burden of heavy protective measures to minimize radiation exposure. Here, we aimed to investigate the safety of task sharing with clinical engineers (CEs) working as 1st assistant during ad hoc PCI. We retrospectively included 286 patients who underwent ad hoc PCI following diagnostic catheterization for coronary artery disease between April 2019 and March 2021. Procedural complications including coronary perforation or rupture, myocardial infarction, cerebral embolism, cardiovascular death, decreased kidney function, and radiation parameters were compared between the two clinical settings [CE group, CEs as the 1st assistant from the beginning of diagnostic coronary angiography to the end of PCI vs. doctor (DR) group, others]. There was no increase in the ratio of procedural complications in the CE group (1.7%) versus the DR group (1.2%). Fluorescence time and radiation exposure dose were significantly reduced in the CE group {25 min [interquartile range (IQR), 19-35 min] vs. 28 min (IQR, 20-39 min), P = 0.036; 908 mGy (IQR, 654-1326 mGy) vs. 1062 mGy (IQR, 732-1594 mGy), P = 0.049}. The median amount of contrast medium was significantly reduced in the CE group [100 mL (IQR, 80-119 mL) vs. 110 mL (IQR 90-140 mL), P < 0.001]. After propensity matching, fluorescence time, radiation exposure dose, and contrast medium amount were similar between groups. Task sharing with CEs as the 1st assistant during ad hoc PCI could contribute to clinical safety in patients with coronary artery disease.

The Early Initiation of Extracorporeal Life Support May Improve the Neurological Outcome in Adults with Cardiac Arrest due to Cardiac Events.

Objective Extracorporeal life support (ECLS) is effective for improving the survival rate of patients with refractory cardiac arrest (rCA). As little data are available regarding the impact of ECLS on a favorable neurological outcome, the predictors of a favorable neurological outcome were evaluated in this study. Methods Between January 2007 and August 2016, we retrospectively recruited patients with rCA caused by cardiac events treated with ECLS in our institute. A favorable neurological outcome was defined as a Glasgow-Pittsburgh cerebral performance category score 1 at discharge. The study endpoint was the clinical outcomes and predictors of favorable neurologic patients at discharge. Results During the study period, 67 patients with CA caused by cardiac events (acute coronary syndrome, 57 patients; idiopathic ventricular fibrillation, 10 patients) were included. Of these, 20 patients (29.9%) were classified into the favorable neurological group. No marked difference was observed in the patient characteristics between those with and without a favorable outcome except for in the time from CA to starting ECLS (ECLS initiation time). A short ECLS initiation time resulted in a favorable outcome (37.8±28.1 minutes vs. 53.6±30.7 minutes, p=0.05). The cut-off time of ECLS initiation was 46 minutes, which was prolonged by the temporary return of spontaneous circulation before ECLS [odds ratio (OR), 3.69; 95% confidence interval (CI), 1.34-10.19; p=0.01] and transfer to the angiographic room (OR, 4.07; 95% CI, 1.44-11.53, p=0.008). Conclusion The early initiation of ECLS (within 46 minutes) might be associated with a favorable neurological outcome for patients with rCA caused by cardiac events.

High-Normal Thyroid-Stimulating Hormone Shows a Potential Causal Association With Arrhythmia Recurrence After Catheter Ablation of Atrial Fibrillation.

BACKGROUND: Hypothyroidism has been shown to contribute to enhanced atrial arrhythmogenesis, resulting in atrial fibrillation (AF) development in animal models and clinical populations. We aimed to elucidate whether high thyroid-stimulating hormone (TSH) levels are related to outcomes of catheter ablation of AF. METHODS AND RESULTS: Of 477 consecutive patients who underwent first-time pulmonary vein isolation-based radiofrequency catheter ablation of AF, 456 with TSH above the lower limit of the normal range (age, 65.5±9.9 years; men, 73.9%; paroxysmal AF, 56.8%) were analyzed for this study. Atrial tachyarrhythmia recurrence for 3 years was compared across groups with hypothyroidism (n=23) and TSH quartile groups with euthyroidism (normal-range TSH levels, n=433). Atrial tachyarrhythmia recurrence occurred in 179 patients (39%) after the first session. Patients with hypothyroidism had increased recurrence compared with patients with normal TSH levels (crude hazard ratio, 3.14 after the last session; P=0.001). When focusing on patients with normal TSH levels, recurrence-free survivals after both the first and last sessions were significantly reduced in euthyroid patients with the highest quartile of TSH levels (quartile 4) compared with others (quartiles 1-3). Cox regression analysis identified high TSH levels as an independent predictor of atrial tachyarrhythmia recurrence after both the first (adjusted hazard ratio, 1.51; P=0.018) and last (adjusted hazard ratio, 1.86; P=0.023) sessions. The difference was more pronounced in patients with paroxysmal AF than in those with nonparoxysmal AF. CONCLUSIONS: Not only hypothyroidism but also high-normal TSH levels may be an independent predictor of atrial tachyarrhythmia recurrence after catheter ablation of AF.

Uninterrupted Direct Oral Anticoagulant and Warfarin Administration in Elderly Patients Undergoing Catheter Ablation for Atrial Fibrillation: A Comparison With Younger Patients.

OBJECTIVES: The goal of this study was to evaluate the efficacy and safety of uninterrupted direct oral anticoagulant (DOAC) use and uninterrupted warfarin administration in elderly patients undergoing catheter ablation for atrial fibrillation (AF). BACKGROUND: There is limited knowledge regarding the uninterrupted use of oral anticoagulant agents in elderly patients undergoing catheter ablation for AF. METHODS: This retrospective study included 2,164 patients (n = 325 ≥75 years of age and n = 1,839 <75 years of age) who underwent catheter ablation for AF. All the patients received uninterrupted oral anticoagulant agents during the procedure. We investigated the occurrences of periprocedural events and compared these between the DOAC and warfarin groups of the elderly and younger groups. RESULTS: Major bleeding events (3.1% vs. 1.3%; p = 0.023) and minor bleeding events (9.2% vs. 5.0%; p = 0.002), except for thromboembolic events (0% vs. 0.8%; p = 0.248), were significantly higher in the elderly group than in the younger group. No significant differences in thromboembolic and bleeding events were found between the DOAC and warfarin groups of both the elderly and younger groups. Adverse complications did not differ between the groups after adjustment using propensity score matching analysis. Multivariate analysis revealed that lower body weight (odds ratio: 0.96; p = 0.010) and antiplatelet drug use (odds ratio: 2.21; p = 0.039) were independent predictors of adverse events in the elderly group. CONCLUSIONS: The periprocedural bleeding risk during the use of uninterrupted oral anticoagulants was higher in the elderly group than in the younger group. This area needs more attention for these patients in whom caution is required.

Assessment of autonomic nervous system modulation after novel catheter ablation techniques for atrial fibrillation using multiple short-term electrocardiogram recordings.

PURPOSE: The effect of novel catheter ablation techniques for atrial fibrillation (AF) on the autonomic nervous system (ANS) is unclear. This study aimed to assess the ANS after three novel catheter ablation techniques for paroxysmal AF by evaluating heart rate variability (HRV) parameters using a 3-min electrocardiogram recording. METHODS: Two hundred and thirty-five patients who underwent catheter ablation for paroxysmal AF (119 in irrigated-tip, 51 in contact-force sensing-guided, and 65 patients in second-generation cryoballoon ablation) were included. HRV analysis was performed at baseline and 1, 3, 6, and 12 months after the ablation. RESULTS: The three ablation groups had similarly decreased HRV parameters after the ablation, and this change was maintained > 1 year. A reduction in parasympathetic nervous function was more apparent after the ablation, compared to changes in the sympathetic nervous function. Of the total population, 45 patients had recurrence. Ln high frequency (HF) 12 months after the ablation was significantly higher in the recurrence group than in the non-recurrence group (1.52 ± 0.47 vs. 1.26 ± 0.57 ms2, p = 0.007). Multivariate analysis demonstrated that AF duration (hazards ratio 1.09, 95% confidence interval 1.04-1.15, p = 0.001) and ln HF 12 months after ablation (hazards ratio 1.91, 95% confidence interval 1.12-3.25, p = 0.017) were independent predictors of AF recurrence after the ablation. CONCLUSIONS: ANS modulation after the three catheter ablation methods was similar and maintained > 1 year after the procedure. Higher parasympathetic nervous function at 1 year after ablation was associated with AF recurrence after the ablation.

Renal function and risk of stroke and bleeding in patients undergoing catheter ablation for atrial fibrillation: Comparison between uninterrupted direct oral anticoagulants and warfarin administration.

BACKGROUND: The effect of uninterrupted oral anticoagulant use in patients with chronic kidney disease (CKD) during catheter ablation for atrial fibrillation (AF) is not fully understood. OBJECTIVE: The present study aimed to evaluate the safety and efficacy of periprocedural uninterrupted direct oral anticoagulant (DOAC) use compared with those of uninterrupted warfarin use in patients undergoing catheter ablation for AF stratified by various renal function groups. METHODS: A total of 2091 patients were retrospectively included in this study. The study population was divided into 4 groups: creatinine clearance level ≥80 mL/min (n = 1086), 50-79 mL/min (n = 774), 15-49 mL/min (n = 209), and <15 mL/min (n = 22). We investigated periprocedural complications and compared them between uninterrupted DOAC and warfarin groups. RESULTS: There was no significant difference in thromboembolic events among the 4 groups (0.6%, 0.6%, 1.0%, and 0%, respectively; P = .792). However, major bleeding events (0.9%, 1.4%, 4.8%, and 4.5%; P < .001) and minor bleeding events (4.1%, 6.1%, 11.5%, and 13.6%; P < .001) primarily occurred in patients with CKD. The rate of periprocedural complications in the DOAC group was similar to that in the warfarin group for each renal function category. Adverse events did not differ after adjustment using propensity score-matched analysis. Multivariate analysis showed that lower body weight, antiplatelet drug use, initial ablation session, and CKD were independent predictors of adverse events. CONCLUSION: The periprocedural bleeding risk was increased in patients with CKD. Uninterrupted DOAC and warfarin administration during catheter ablation for AF in patients with CKD is feasible and effective.

Impact of basal inferolateral scar burden determined by automatic analysis of 99mTc-MIBI myocardial perfusion SPECT on the long-term prognosis of cardiac resynchronization therapy.

AIMS: Left-ventricular (LV) scarring may be associated with a poor response to cardiac resynchronization therapy (CRT). The automatic analysis of myocardial perfusion single-photon emission computed tomography (MP-SPECT) may provide objective quantification of LV scarring. We investigated the impact of LV scarring determined by an automatic analysis of MP-SPECT on short-term LV volume response as well as long-term outcome. METHODS AND RESULTS: We studied consecutive 51 patients who were eligible to undergo 99mTc-MIBI MP-SPECT both at baseline and 6 months after CRT (ischaemic cardiomyopathies 31%). Quantitative perfusion SPECT was used to evaluate the defect extent (an index of global scarring) and the LV 17-segment regional uptake ratio (an inverse index of regional scar burden). The primary outcome was the composite of overall mortality or first hospitalization for worsening heart failure. A high global scar burden and a low mid/basal inferolateral regional uptake ratio were associated with volume non-responders to CRT at 6 months. The basal inferolateral regional uptake ratio remained as a predictor of volume non-response after adjusting for the type of cardiomyopathy. During a median follow-up of 36.1 months, the outcome occurred in 28 patients. The patients with a low basal inferolateral regional uptake ratio with a cutoff value of 57% showed poor prognosis (log-rank P= 0.006). CONCLUSION: The scarring determined by automatic analysis of MP-SPECT images may predict a poor response to CRT regardless of the pathogenesis of cardiomyopathy. The basal inferolateral scar burden in particular may have an adverse impact on long-term prognosis.

Comparison of Frequency and Characteristics of Patients With Atrial Fibrillation Having Ablation With Versus Without Coronary Narrowing (≥50%) by Angiography.

Atrial fibrillation (AF) shares background comorbidities with coronary artery disease (CAD), including hypertension and diabetes mellitus. The aim of the study is to evaluate the prevalence, risk factors, and prognostic significance of CAD among patients who underwent catheter ablation for AF. In 544 consecutive registered patients who underwent catheter ablation for AF (CHADS2 score 1.2 ± 1.1, paroxysmal AF 57%), quantitative coronary angiography was used to detect CAD, defined as luminal narrowing of ≥50% in diameter. Univariate and multiple logistic regression analyses were applied to evaluate the risk factors of CAD. Subsequent clinical events up to 1 year were obtained in all the patients. CAD was found in 70 patients (13%). The factors associated with the presence of CAD in AF patients who underwent catheter ablation were similar to traditional coronary risk factors such as hypertension and diabetes mellitus. AF patients with CAD had a higher CHADS2 score than those without CAD (1.5 ± 1.1 vs 1.1 ± 1.0, p = 0.009). Hence, a CHADS2 score ≥1 may be an alternative risk factor to predict CAD. Previous coronary revascularization (14% with CAD vs 6% without CAD) and paroxysmal AF (69% vs 55%) were also associated with CAD. During follow-up, patients with CAD experienced acute coronary syndrome (n = 2) and coronary revascularization (n = 18); no such events were recorded in those without CAD. In addition to traditional risk factors, CHADS2 score, previous revascularization, and paroxysmal AF may be new risk factors for CAD in AF patients.

Non-vitamin K antagonist oral anticoagulants versus warfarin for cardioversion of atrial fibrillation in clinical practice: A single-center experience.

BACKGROUND: Anticoagulation therapy with the vitamin K antagonist (VKA) warfarin has been demonstrated to reduce thromboembolic risk after electrical cardioversion (ECV). However, data concerning ECV with non-VKA oral anticoagulants (NOACs) is limited. The objective of this study was to determine the efficacy and safety of NOACs in patients undergoing ECV in a real-world clinical practice at a single center in Japan. METHODS: We retrospectively analyzed the data of 406 consecutive patients who underwent ECV for atrial fibrillation (AF) or flutter under anticoagulation with one of the three NOACs (n=149) or with a VKA (n=257). RESULTS: The CHADS2 and HAS-BLED scores were significantly higher in the VKA group, whereas the NOACs group had a tendency toward greater spontaneous echo contrast grades. After ECV, ischemic stroke occurred in three patients of the VKA group and one patient in the NOAC group, all of whom had persistent AF, indicating no significant difference in the thromboembolic event rate within 30 days following ECV. No other thromboembolic events, major bleeding, or death occurred in either group. Among the NOAC and VKA patients in whom we newly introduced an oral anticoagulant to perform ECV, the number of days leading to ECV was significantly lesser for the NOAC patients. CONCLUSION: NOACs may be used as an alternative to VKAs for ECV and may allow prompt ECV in clinical practices.