Efficacy and feasibility of cryoballoon ablation for atrial fibrillation in patients with heart failure: A large-scale multicenter study.

INTRODUCTION: Data are limited regarding outcomes of cryoballoon ablation for atrial fibrillation (AF) in patients with heart failure (HF). This large-scale multicenter study aimed to evaluate the prognosis of patients with HF after cryoballoon ablation for AF. METHODS: Among 3655 patients undergoing cryoballoon ablation at 17 institutions, 549 patients (15%) (391 with paroxysmal AF and 158 with persistent AF) diagnosed with HF preoperatively were analyzed. Clinical endpoints were recurrence, mortality, and HF hospitalization after ablation. RESULTS: Most patients had a preserved left ventricular ejection fraction (LVEF) ≥ 50%. During a mean follow-up period of 25.7 months, recurrence, all-cause death, and HF hospitalization occurred in 29%, 4.0%, and 4.8%, respectively. Cardiac function on echocardiography and B-type natriuretic peptide (BNP) levels significantly improved postoperatively, and the effect was more pronounced in the nonrecurrence group. Major complications occurred in 33 patients (6.0%), but most complications were phrenic nerve palsy (3.6%). Although death and HF hospitalization occurred more frequently in patients with LVEF ≤ 40% (n = 73) and New York Heart Association (NYHA) class III-IV (n = 19) than other subgroups, the BNP levels, and LVEF significantly improved after ablation in all LVEF and NYHA class subgroups. High BNP levels, NHYA class, CHADS2 score, and structural heart disease, but not postablation recurrence, independently predicted death, and HF hospitalization on multivariate analysis. The patients with tachycardia-induced cardiomyopathy had better recovery of BNP levels and LVEF after ablation than those with structural heart disease. CONCLUSIONS: Cryoballoon ablation for AF in HF patients is feasible and leads to significantly improved cardiac function.

Study design and protocol for evaluating the long-term prognosis of patients receiving his bundle pacing: A multicenter observational study.

BACKGROUND: His bundle pacing (HBP) is a recently developed pacing technique that can achieve an ideal physiological pattern of ventricular activation via stimulation of the native His-Purkinje system. Despite the widespread introduction of HBP in clinical practice, its appropriate indications are yet to be determined clearly. Moreover, the efficacy and safety of HBP and long-term prognosis of patients undergoing such are unknown. METHODS: We conducted a multicenter observational prospective study in patients undergoing HBP in Japan. Patients with atrioventricular block or conduction delay and estimated ventricular pacing of ≥ 40% scheduled for HBP implantation are included. All patients are followed up until 3 years after the implantation. The primary endpoints are all-cause death, heart failure-related hospitalization, and upgrade to cardiac resynchronization therapy. The secondary endpoint is changes in cardiac function based on echocardiographic findings and laboratory data after the implantation. RESULTS: The results are currently under investigation. CONCLUSIONS: This multicenter observational study evaluates the long-term prognosis and changes in cardiac function of patients undergoing HBP implantation in a clinical setting. Considering the large number of patients included, the cumulative results would be helpful in establishing evidence on HBP application in this area and consequently allow accurate management and treatment of patients undergoing HBP.

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.

Vagal response in cryoballoon ablation of atrial fibrillation and autonomic nervous system: Utility of epicardial adipose tissue location.

BACKGROUND: Mechanism and effects of vagal response (VR) during cryoballoon ablation procedure on the cardiac autonomic nervous system (ANS) are unclear. The present study aimed to evaluate the relationship between VR during cryoballoon catheter ablation for atrial fibrillation and ANS modulation by evaluating epicardial adipose tissue (EAT) locations and heart rate variability (HRV) analysis. METHODS: Forty-one patients with paroxysmal atrial fibrillation (11 with VR during the procedure and 30 without VR) who underwent second-generation cryoballoon ablation were included. EAT locations and changes in HRV parameters were compared between the VR and non-VR groups, using Holter monitoring before ablation, immediately after ablation and one month after ablation. RESULTS: The total EAT volume surrounding the left atrium (LA) in the VR and non-VR groups was 29.0±18.4 cm3 vs 27.7±19.7 cm3, respectively (p=0.847). The VR group exhibited greater EAT volume overlaying the LA-left superior pulmonary vein (PV) junction (6.1±3.6 cm3 vs 3.6±3.3 cm3, p=0.039) than the non-VR group. HRV parameters similarly changed following ablation in both the groups. EAT volume overlaying LA-right superior PV junction was significantly correlated with the relative changes in root-mean-square successive differences (r=-0.317, p=0.043) and high frequency (r=-0.331, p=0.034), immediately after the ablation. CONCLUSIONS: Changes in HRV parameters following ablation were similarly observed in both the groups. EAT volume on the LA-PV junction is helpful for interpretation of VR occurrence and ANS modulation.

Impaired renal function is associated with recurrence after cryoballoon catheter ablation for paroxysmal atrial fibrillation: A potential effect of non-pulmonary vein foci.

BACKGROUND: Atrial fibrillation (AF) and chronic kidney disease (CKD) are closely related. The present study aimed to evaluate the association between estimated glomerular filtration rate (eGFR) and outcomes after cryoballoon catheter ablation for AF. METHODS: We included a total of 110 patients (64.0±10.1 years, 64% men) with paroxysmal AF who underwent second-generation cryoballoon catheter ablation in this study. Recurrence and change in renal function after ablation were assessed by stratification of eGFR sub-groups. RESULTS: During a mean follow-up period of 9 months, 20 (18%) patients had AF recurrence after the first catheter ablation procedure. Multivariate Cox regression analysis showed that eGFR [hazard ratio (HR) 0.97, 95% confidence interval (CI) 0.93-0.99, p=0.047], non-pulmonary vein (PV) ectopic beats at initial ablation (HR 2.92, 95% CI 1.03-8.27, p=0.043), and history of stroke (HR 7.47, 95% CI 2.30-24.2, p=0.001) were independent predictors of recurrence after the ablation. Among the CKD groups, recurrence was found in 7% (1/15), 12% (9/73), and 46% (10/22) of the eGFR ≥90mL/min/1.73m2, eGFR 60-89.9mL/min/1.73m2, and eGFR 30-59.9mL/min/1.73m2 groups, respectively (p=0.001). Kaplan-Meier survival curves demonstrated that patients with eGFR 30-59.9mL/min/1.73m2 had significantly worse prognosis than did the other groups (log-rank p<0.001). In addition, non-PV ectopic beats at initial ablation were detected in 7% (1/15), 14% (10/73), and 50% (11/22) of the patients among the three CKD groups, respectively (p<0.001). No patients developed contrast-induced nephropathy after the catheter ablation procedure. CONCLUSIONS: Low eGFR at baseline was an independent predictor of recurrence after cryoballoon ablation for paroxysmal AF. The presence of non-PV ectopic beats was significantly increased in patients with impaired renal function, which might be associated with a poor outcome.

An ECG Index of P-Wave Force Predicts the Recurrence of Atrial Fibrillation after Pulmonary Vein Isolation.

BACKGROUND: Although several prognostic factors of atrial fibrillation (AF) recurrence after pulmonary vein isolation (PVI) have been investigated, the accurate prediction of AF recurrence remains difficult. We propose an electrocardiogram (ECG) index, the P-wave force (PWF), which is the product of the amplitude of the negative terminal phase of the P wave in the V1 electrode and the filtered P-wave duration, obtained by a signal-averaged P-wave analysis. This study was conducted to evaluate the impact of the PWF on the recurrence of AF after PVI. METHODS: We retrospectively evaluated 79 paroxysmal AF patients (64 ± 9 years, 56 males) who underwent PVI by cryoballoon ablation. Standard 12-lead ECG and a P-wave signal-averaged electrocardiogram (SAECG) were recorded the day before and 1 month after the PVI procedure. RESULTS: During the mean follow-up of 10.2 months, AF recurred in 11 (14%) patients. The PWF 1 month after ablation was significantly higher in the recurrence group compared to that in the nonrecurrence group (8.8 ± 3.1 mVms vs 6.5 ± 2.9 mVms, P = 0.017). The patients with a PWF value ≥9.3 mVms had a significantly greater risk of recurrence after the ablation compared to the patients with a PWF value <9.3 mVms (log-rank test, P < 0.001). CONCLUSION: Higher PWF after cryoballoon ablation was associated with poor prognosis during follow-up. The PWF may be a useful and noninvasive marker to predict the recurrence of AF.

Effect and Significance of Early Reablation for the Treatment of Early Recurrence of Atrial Fibrillation After Catheter Ablation.

There are few reports on early reablation (ER) for early recurrence of atrial fibrillation (AF) after catheter ablation. The present study evaluated the efficacy and significance of ER for early recurrence within a blanking period of 3 months after ablation of both paroxysmal and persistent AF, using a propensity-matched analysis. Of 874 patients who underwent catheter ablation of AF, 389 (45%) had early recurrence. Of these, 78 patients underwent an ER procedure. A total of 132 matched patients (66 in the ER and 66 in the non-ER groups, 82 patients with paroxysmal AF) were included in the analysis. During a mean follow-up of 15.4 months, the patients who underwent ER had a significantly lower recurrence rate than those who did not (29 [44%] vs 42 patients [64%], p = 0.023). The benefit of ER was especially apparent in patients with paroxysmal AF (p = 0.008) but not in those with persistent AF (p = 0.774). However, 24 patients (36%) in the non-ER group did not experience recurrence after a blanking period without any reablation procedure. The total number of reablation sessions was higher in the ER group than in the non-ER group (1.2 ± 0.5 vs 0.4 ± 0.6, p <0.001). Nonetheless, mean number of arrhythmia outpatient clinic visits at follow-up was significantly fewer in the ER group than in the late reablation group. In conclusion, ER for early recurrence of AF after catheter ablation might be effective for preventing recurrence during follow-up, especially for paroxysmal AF.

Elevated Red Blood Cell Distribution Width Predicts Recurrence After Catheter Ablation for Atrial Fibrillation in Patients With Heart Failure　- Comparison With Non-Heart Failure Patients.

BACKGROUND: Elevated red blood cell distribution width (RDW) predicts poor prognosis in patients with cardiovascular diseases. However, little is known about the association between RDW and outcomes after catheter ablation of atrial fibrillation (AF). METHODS AND RESULTS: A total of 757 patients who underwent radiofrequency catheter ablation of AF were divided into heart failure (HF, n=79) and non-HF (n=678) groups; RDW was assessed as a predictor after catheter ablation in each. During a 22.3-month follow-up period, the baseline RDW in the HF group was greater in the recurrence group than in the non-recurrence group (14.5±2.0% vs. 13.5±0.9%, P=0.013). In contrast, no significant difference in RDW at baseline was found in the non-HF group between the recurrence and non-recurrence groups (13.3±0.8% vs. 13.2±0.8%, P=0.332, respectively). Multivariate analysis demonstrated that RDW (hazard ratio 1.20, 95% confidence interval 1.01-1.40, P=0.034) was an independent predictor of AF recurrence in the HF group. The cut-off values of RDW for the recurrence of AF and major adverse events in the HF group were 13.9% and 14.8%, respectively. CONCLUSIONS: High RDW is an independent predictor for the recurrence of AF and major adverse events in patients with HF after catheter ablation. RDW is a potential noninvasive marker in AF patients complicated with HF. (Circ J 2016; 80: 627-638).

Body mass index is associated with prognosis in Japanese elderly patients with atrial fibrillation: an observational study from the outpatient clinic.

The relationship between body mass index (BMI) and the prognosis of elderly patients with atrial fibrillation (AF) is unknown. We aimed to examine the association of body weight with the clinical outcomes among Japanese elderly patients with a history of documented AF. This observational study of AF patients from an outpatients clinic in Nagoya University Hospital included 413 patients ≥70 years old (99 obese: BMI ≥25 kg/m(2); 256 normal weight: BMI 18.5-24.9 kg/m(2); and 58 underweight patients: BMI <18.5 kg/m(2)). The mean age was 77.5 ± 5.6 years. During a mean follow-up of 19.0 months, all-cause death occurred in 23 patients (obese 1 %, normal weight 5.1 %, and underweight 16 %). The major adverse events including all-cause death, stroke or transient ischemic attack, heart failure requiring admission, and acute coronary syndrome were observed in 53 patients (obese 5.1 %, normal weight 13 %, and underweight 26 %). After adjusting for confounding factors, the underweight group had a significantly greater risk for all-cause death [hazard ratio (HR) 2.91, 95 % confidence interval (CI) 1.12-7.60, p = 0.029], and major adverse events (HR 2.45, 95 % CI 1.25-4.78, p = 0.009) than the normal weight group. In contrast, the obese group had a better prognosis in major adverse events compared with the normal weight group (HR 0.34, 95 % CI 0.13-0.89, p = 0.029). In conclusion, lower BMI was independently associated with poor outcomes among older AF patients. The association between obesity and better prognosis in elderly AF patients was also found.

Decrease in B-Type Natriuretic Peptide Levels and Successful Catheter Ablation for Atrial Fibrillation in Patients with Heart Failure.

BACKGROUND: Little is known about the association between B-type natriuretic peptide (BNP) levels and catheter ablation of atrial fibrillation (AF) in patients with heart failure. This study aimed to examine the impact of elimination of AF by catheter ablation on BNP levels in patients with left ventricular systolic dysfunction. METHODS: Fifty-four AF patients with left ventricular ejection fraction (LVEF) ≤ 50%, who underwent radiofrequency catheter ablation therapy of AF, were included. BNP sampling was performed at baseline, 3 days, and 1 month after ablation. RESULTS: After a follow-up period of 6 months, the BNP levels decreased significantly in the nonrecurrence group (n = 35; median 126.3 [interquartile 57.2-206.5] pg/mL, 63.5 [23.9-180.2] pg/mL, and 45.9 [21.9-160.3] pg/mL, P < 0.001, respectively), but not in the recurrence group (n = 19; 144.7 [87.1-217.3] pg/mL, 88.8 [12.9-213.2] pg/mL, and 118.5 [51.6-298.2] pg/mL, P = 0.368, respectively). The patients in the nonrecurrence group had a higher percentage relative reduction in BNP levels from baseline to 1 month after ablation than those in the recurrence group (56.5 [-9.0-77.4]% vs -2.4 [-47.1-60.9]%, P = 0.027). Additionally, a relative reduction in BNP levels significantly correlated with an increase in LVEF after ablation (r = 0.486, P < 0.001). CONCLUSIONS: Plasma BNP levels decreased significantly with successful catheter ablation of AF in patients with impaired LVEF. The decrease in BNP levels might be associated with early recovery of cardiac function and subsequent maintenance of sinus rhythm at follow-up.