Increase in heart rate-dependent left atrial pressure is associated with symptoms in patients with paroxysmal atrial fibrillation.

BACKGROUND: It remains unclear why some patients with the same heart rate during an atrial fibrillation (AF) have subjective symptoms, whereas others do not. We assessed the hypothesis that different responses of arterial and left atrial blood pressures to rapid stimulation may be associated with the symptoms of AF. METHODS: A total of 110 patients who underwent catheter ablation for paroxysmal AF were retrospectively studied. Asymptomatic AF was defined as a European Heart Rhythm Association score of Ⅰ for AF-related symptoms. The left atrial pressure (LAP) was measured during sinus rhythm (SR), in 10 pacing per minute (ppm) increments from 100 ppm to the Wenckebach block rate in high right atrial pacing. RESULTS: Asymptomatic AF was observed in 19/110 patients (17%). Patients with symptomatic AF showed higher E/e' ratio and gradual LAP increase that was dependent on the pacing rate. Patients with asymptomatic AF had decreased LAP at 100 ppm compared that at SR, and thereafter, LAP gradually increased depending on the pacing rate. The rate of LAP change compared to that at SR was significantly lower in patients with asymptomatic AF than that in patients with symptomatic AF. The rate of LAP change was independently associated with AF symptoms. CONCLUSION: Patients with asymptomatic AF showed lower E/e' ratio and decreased LAP at 100 ppm to rapid stimulation, followed by a steady increase in LAP afterwards. Factors other than left ventricular diastolic dysfunction may be involved in AF symptoms.

Post-ablation left atrial function impacts long-term recurrence of atrial fibrillation after ablation.

Left atrial (LA) function can help predict various cardiovascular events. Catheter ablation for atrial fibrillation (AF) modifies baseline LA function through the maintenance of sinus rhythm and myocardial injury. We investigated the impact of post-ablation LA function on recurrence of AF after ablation and identified the predictors of reduced post-ablation LA function. A total of 616 patients who underwent AF ablation (paroxysmal, N = 310; non-paroxysmal, N = 306) were retrospectively examined with cardiac computed tomography at baseline and 3 months after the final ablation procedure. Post-ablation LA emptying fraction (LAEFpost) was calculated. We evaluated the association between LAEFpost and recurrence of AF after the final ablation procedure. Further, we assessed the predictors of reduced LAEFpost. The recurrence rate of AF was 72.7% after the final ablation procedure [median follow-up 48 months (48.0, 48.0), total number of ablation sessions: 1.4 ± 0.7]. Multivariate analysis revealed that LAEFpost was associated with the recurrence of AF (hazard ratio/10% increase: 0.62, 95% confidence interval: 0.51-0.75, P < 0.0001). LAEFpost had a mild predictive power for recurrence of AF (c-statistics: 0.670, optimal cutoff: 26.36%, P < 0.0001). The recurrence-free proportion among patients with reduced LAEFpost (< 26.36%, N = 100) and those with preserved LAEFpost (≥ 26.36%, N = 516) was 40% and 79%, respectively (P < 0.0001). The predictors of reduced LAEFpost were low pre-ablation LAEF, high pre-ablation LA volume, low body mass index (BMI), and female sex. Further, reduced LAEFpost was associated with the total number of ablation sessions and extra-pulmonary vein LA ablation. In conclusion, reduced LAEFpost was associated with recurrence of AF after ablation. Advanced LA remodeling, low BMI, and female sex could predict reduced LAEFpost. Although additional ablation was associated with reduced LAEFpost, it remains unclear whether reduced LAEFpost resulted from the additional ablation. Reduced LAEFpost might help stratify patients with ablation-refractory AF.

Burden and Long Firing of Premature Atrial Contraction Early After Catheter Ablation Predict Late Recurrence of Atrial Fibrillation.

BACKGROUND: Associations between characteristics of premature atrial contraction (PAC) 6 months after catheter ablation (CA) and later recurrence are not known. We investigated the effects of PAC characteristics on long-term outcomes of initially successful atrial fibrillation (AF) ablation.Methods and Results:In all, 378 patients (mean age 61 years, 21% female, 67% paroxysmal AF) who underwent initial radiofrequency CA for AF without recurrence up to 24-h Holter monitoring 6 months after the procedure were reviewed retrospectively. The calculated number of PAC/24 h and the length of the longest PAC run during Holter recording were analyzed. After 4.3±1.2 years (mean±SD) follow-up, 123 (32.5%) patients experienced late recurrence. Patients with recurrence had significantly more PAC/24 h (median [interquartile range] 110 [33-228] vs. 42 [16-210]; P<0.01) and a longer longest PAC run (5 [2-8] vs. 3 [1-5]; P<0.01) than those without. Receiver operating characteristic curve analysis indicated 58 PAC/24 h and a longest PAC run of 5 were optimal cut-off values for predicting recurrence. After adjusting for previously reported predictors of late recurrence, frequent PAC (≥58/24 h) and longest PAC run ≥5 were found to be independent predictors of late recurrence (hazard ratios [95% confidence intervals] 1.93 [1.24-3.02; P<0.01] and 1.81 [1.20-2.76; P<0.01], respectively). CONCLUSIONS: Six months after successful AF ablation, both frequent PAC and long PAC run are independent predictors of late recurrence.

Comparison of the Safety and Efficacy of Automated Annotation-Guided Radiofrequency Ablation and 2nd-Generation Cryoballoon Ablation in Paroxysmal Atrial Fibrillation.

BACKGROUND: Automated ablation lesion annotation with optimal settings for parameters including contact force (CF) and catheter stability may be effective for achieving durable pulmonary vein isolation. Methods and Results: We retrospectively examined 131 consecutive patients who underwent initial catheter ablation (CA) for paroxysmal atrial fibrillation (PAF) by automatic annotation system (VISITAG module)-guided radiofrequency CA (RFCA) (n=61) and 2nd-generation cryoballoon ablation (CBA) (n=70) in terms of safety and long-term efficacy. The automatic annotation criteria for the RFCA group were as follows: catheter stability range of motion ≤1.5 mm, duration ≥5 s, and CF ≥5 g. We ablated for >20 s with a force-time integral >150 gs at each site, before moving to the next site. Each interlesion distance was <6 mm. Procedural complications were more frequent in the CBA group (1.6% vs. 10.0%, P=0.034). Across a median follow-up of 2.98 years, 88.5% and 70.0% of patients in the RFCA and CBA groups, respectively, were free from recurrence (log-rank test, P=0.0039). There was also a significant difference in favor of RFCA with respect to repeat ablations (3.3% vs. 24.3%, log-rank test, P=0.0003). CONCLUSIONS: RF ablation guided by an automated algorithm that includes CF and catheter stability parameters showed better long-term outcomes than CBA in the treatment of patients with PAF without increasing complications.

Efficacy of Sodium-Glucose Cotransporter 2 Inhibitors on Outcomes After Catheter Ablation for Atrial Fibrillation.

BACKGROUND: Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have recently been a significant focus of attention because of their multiple pleiotropic effects. However, the impact of SGLT2i on atrial fibrillation (AF) remains unclear. OBJECTIVES: The goal of this study was to examine the effects of SGLT2i on AF after catheter ablation (CA). METHODS: This prospective, randomized controlled study compared the suppressive effect of SGLT2i vs dipeptidyl peptidase-4 inhibitors on AF recurrence after CA. Eighty AF patients with type 2 diabetes mellitus were randomized (by a computer-generated random sequence) to the tofogliflozin group (20 mg/d) or the anagliptin group (200 mg/d) stratified according to left atrial diameter and AF type (paroxysmal AF [PAF] or non-paroxysmal atrial fibrillation [PAF]) at screening. The primary outcome was AF recurrence at 12 months after CA. RESULTS: Seventy patients were analyzed (mean age 70.3 ± 8.1 years; 48 male; 30 with paroxysmal AF; 38 tofogliflozin treated). Recurrent AF was detected in 24 (34.3%) of 70 patients, and the AF recurrence ratio was higher in the anagliptin group than in the tofogliflozin group (15 of 32 patients [47%] vs 9 of 38 patients [24%]; P = 0.0417). Moreover, univariate analysis revealed that compared with the nonrecurrence group (n = 46), the recurrence group (n = 24) had a higher prevalence rate of non-PAF, elevated brain natriuretic peptide, higher urinary albumin-creatinine ratio, lower rate of SGLT2i use, larger left atrial diameter, elevated E wave, lower left ventricular ejection fraction, and lower rate of cryoballoon pulmonary vein isolation. CONCLUSIONS: Compared with anagliptin, tofogliflozin achieved greater suppression of AF recurrence after CA in patients with type 2 diabetes mellitus.

Absence of first-pass isolation is associated with poor pulmonary vein isolation durability and atrial fibrillation ablation outcomes.

BACKGROUND: Pulmonary vein (PV) reconnection is the main cause of atrial fibrillation (AF) recurrence. This study aimed to examine the effect of first-pass PV isolation (PVI) on PV reconnection frequency during the procedure and on AF ablation outcomes. METHODS: This retrospective study included 446 patients with drug-refractory AF (370 men, aged 64 ± 10 years) who underwent initial PVI using an open-irrigated contact force catheter between January 2015 and October 2016. We investigated the effect of first-pass PVI on PV reconnection during spontaneous PV reconnection and dormant conduction after an adenosine triphosphate challenge. RESULTS: First-pass PVI was achieved in 69% (617/892) of ipsilateral PVs, of which we observed PV reconnection during the procedure in 134 (22%) PVs. This value was significantly lower than that observed in those without first-pass PVI (50%, 138/275) (P < .0001). We divided the subjects into two groups based on the presence or absence of first-pass PVI in at least one of two ipsilateral PVs: first-pass (n = 383, 86%) and non-first-pass groups (n = 63, 14%). The 2-year AF recurrence-free rate was significantly higher in the first-pass group than in the other group (75% vs 59%, log-rank P = .032). In 78 patients with repeat AF ablation, the PV reconnection rate in the second procedure was significantly lower in PVs that had first-pass isolation in the first procedure (34% vs 73%, P < .0001). CONCLUSIONS: Absence of first-pass PVI was associated with a higher frequency of spontaneous PV reconnection and dormant conduction and poor ablation outcomes. First-pass isolation may be a useful marker for better PVI durability.

Clinical significance of left ventricular reverse remodeling after catheter ablation of atrial fibrillation in patients with left ventricular systolic dysfunction.

BACKGROUND: Left ventricular (LV) reverse remodeling (LVRR) after catheter ablation of atrial fibrillation (AFCA) has not been fully described. This study investigated the predictors and clinical outcomes of LVRR after AFCA in patients with LV systolic dysfunction. METHODS: Of 3319 consecutive patients who underwent first-time AFCA between January 2012 and October 2019, 376 with a baseline LV ejection fraction of <50% were retrospectively evaluated. They were subjected to 256-slice multidetector computed tomography (MDCT) scanning at baseline and 3 months after AFCA. The LVRR was defined as a decrease in the LV end-systolic volume of ≥15%. RESULTS: The prevalence of LVRR was 83% (n = 306). Multivariate logistic regression analysis including age, body mass index, diabetic status, beta-blocker use, and LV diastolic diameter revealed that the predictors of LVRR were non-paroxysmal atrial fibrillation (AF) (odds ratio, 2.68; 95% confidence interval, 1.42-5.05; p = 0.002) and absence of apparent underlying structural heart disease (4.81; 2.31-10.0; p <0.001). The prevalence of LVRR differed depending on AF recurrence pattern prior to the post-MDCT [no episode vs. paroxysmal episode (lasting <7 days) vs. persistent episode (lasting ≥7 days), 84% vs. 81% vs. 63%, respectively, p = 0.023]. During a median follow-up of 32 months, the incidence of paroxysmal form of AF recurrence was similar, whereas persistent form of AF recurrence was less frequent in patients with LVRR (10.5% vs. 18.6%, p = 0.018). Heart failure hospitalizations (2.3% vs. 15.7%, p <0.001), cardiovascular deaths (0.7% vs. 4.3%, p = 0.015), and all-cause deaths (1.3% vs. 5.7%, p = 0.018) were similarly less frequent in those with LVRR. CONCLUSIONS: LVRR after AFCA, which was predicted by non-paroxysmal AF without any apparent structural heart disease at baseline, was associated with persistent form of AF recurrence prior to the evaluation. LVRR was associated with favorable clinical outcomes.

Early recurrence during the blanking period and left atrial reverse remodeling after catheter ablation for non-paroxysmal atrial fibrillation.

BACKGROUND: Early recurrence of atrial tachyarrhythmia (ERAT) during a 90-day blanking period (BP) often occurs after atrial fibrillation (AF) ablation. Left atrial reverse remodeling (LARR), which is the reduction in LA volume (LAV), also occurs during the BP. Both ERAT and LARR are associated with late recurrence (LR, greater than 90 days after ablation). We investigated the association between ERAT and LARR following non-paroxysmal AF (NPAF) ablation. METHODS: We retrospectively reviewed 330 consecutive patients undergoing initial NPAF ablation (median follow-up: 4.0 years). Based on the timing of the final ERAT, we divided the patients into No-ERAT (N = 154, without ERAT), Early (N = 39, 0-7 days after ablation), Intermediate (N = 67, 8-30), and Late-ERAT (N = 70, 31-90) groups. We assessed the extent of LARR, defined as the percentage of decrease in LAV (%ΔLAV). The %ΔLAV cutoff value was determined by receiver operating characteristic analysis, and incorporated into a multivariate analysis to assess the association between ERAT and LARR. RESULTS: Late-ERAT was associated with LR (hazard ratio: 6.31, 95% confidence interval (CI): 4.21-9.47, p = 0.0001). The %ΔLAV in the Late-ERAT group was significantly smaller than the other groups (p < 0.0001). The predictive power of %ΔLAV for LR was slight (AUC, 0.604; best cutoff, 18.8% decrease; p = 0.0011). In the multivariate logistic regression analysis, Late-ERAT was associated with poor LARR (%ΔLAV < 18.8% decrease) (odds ratio, 0.13; 95%CI, 0.06-0.27; p < 0.001), whereas Early- and Intermediate-ERAT did not show any correlation. CONCLUSIONS: Late-ERAT was strongly associated with poor LARR after NPAF ablation. Both Late-ERAT and poor LARR might reflect a residual arrhythmogenic substrate causing LR.

A case of pulseless electrical activity due to takotsubo syndrome following radiofrequency catheter ablation for atrial fibrillation.

A 51-year-old man with normal left ventricular ejection fraction (LVEF) underwent radiofrequency catheter ablation (RFCA) for long-standing persistent atrial fibrillation (AF). After isolating the pulmonary veins (PV), we attempted to ablate multiple non-PV AF triggers evoked by isoproterenol and performed repetitive intracardiac electrical cardioversion under considerable dose of barbiturate. Finally, administration of pilsicainide was required to maintain sinus rhythm. Sixty minutes after the procedure, initiation of development of rapid ST-segment elevation was observed on the continuous electrocardiogram monitor and the patient complained of general fatigue. There was occurrence of complete atrioventricular block and he immediately fell into pulseless electrical activity (PEA). Cardiopulmonary resuscitation was initiated and a percutaneous cardiopulmonary system (PCPS) was provided. Echocardiogram showed severe biventricular systolic dysfunction. Although ST-segment change sustained, emergent coronary angiography was normal. Left ventriculogram showed apical to mid ventricular akinesia and preserved basal contractibility, which was typical of takotsubo syndrome (TS). Fortunately, he recovered completely; the PCPS was weaned on day 5, and the LVEF normalized within 2 weeks without any neurological disorders. This is the first case report of PEA due to TS following AF ablation. TS due to stressors of RFCA procedure should be recognized as a possible life-threatening complication. .

Impact of baseline left atrial function on long-term outcome after catheter ablation for paroxysmal atrial fibrillation.

BACKGROUND: Left atrial (LA) size is an established predictor of recurrence after catheter ablation for paroxysmal atrial fibrillation (PAF). We investigated the impact of baseline LA function on recurrence after PAF ablation and compared the predictive values of LA function with those of LA size. METHODS: We retrospectively investigated 292 consecutive patients who underwent PAF ablation (median follow-up: 3.0 years). All patients had their preoperative LA volume (LAV) assessed using cardiac computed tomography under sinus rhythm. We used LA emptying fraction (LAEF) as an indicator of LA function and assessed the association between baseline LAEF and recurrence after initial ablation using a multivariate Cox hazard model. Then, we performed receiver operating characteristic analysis for predicting recurrence after single and multiple procedures and compared the c-statistics of LAEF and indexed maximum and minimum LAV (LAVImax and LAVImin) RESULTS: In a multivariate Cox hazard model, LAEF was strongly associated with recurrence after a single procedure [hazard ratio (HR): 0.968, 95% confidence interval (CI): 0.951-0.985, p < 0.001]. In the receiver operating characteristic analysis for predicting recurrence, the predictive accuracy of LAEF was mild after a single procedure [area under the curve (AUC): 0.666, p < 0.001] and moderate after multiple procedures (AUC: 0.701, p < 0.001). The c-statistic of LAEF was significantly higher than those of LAVImax and LAVImin after a single procedure (p < 0.05, for both). After adjustment for factors related to reduced LAEF (increased serum brain natriuretic peptide, age, LA diameter, and reduced left ventricular ejection fraction), it was still associated with recurrence (HR: 0.964, 95% CI: 0.946-0.982, p < 0.001). CONCLUSIONS: LAEF was associated with recurrence after PAF ablation. LA function is a more useful predictor than LA size.