Comparison of myocardial injury and inflammation after pulmonary vein isolation for paroxysmal atrial fibrillation between radiofrequency catheter ablation and cryoballoon ablation

Prevalence, timing, and impact of early recurrence of atrial tachyarrhythmias after pulsed field ablation: A secondary analysis of the PULSED AF trial

BACKGROUND

Early recurrence of atrial tachyarrhythmias (ERAT) within 3 months of thermal ablation for atrial fibrillation (AF) is common and often considered transient. Pulsed field ablation (PFA) is a nonthermal energy source in which ERAT is not well described.

OBJECTIVE

The purpose of this study was to analyze ERAT in patients with AF undergoing PFA in the Pulsed Field Ablation to Irreversibly Electroporate Tissue and Treat AF (PULSED AF) trial.

METHODS

This analysis included 154 (52.4%) paroxysmal AF and 140 (47.6%) persistent AF who had ≥10 rhythm assessments during the 90-day blanking period. ERAT was defined as any instance of ≥30 seconds of AF, atrial flutter, or atrial tachycardia on transtelephonic monitoring (weekly and symptomatic) or ≥10 seconds on electrocardiography (at 3 months), both within 90 days. Late recurrence of atrial tachyarrhythmias (LRAT) was defined as observed atrial tachyarrhythmias between 90 days and 12 months.

RESULTS

The overall prevalence of ERAT was 27.1% in patients with paroxysmal AF and 31.6% in patients with persistent AF. In patients with ERAT, 73% had ERAT onset within the first month of the procedure. The presence of ERAT was associated with LRAT in patients with paroxysmal AF (hazard ratio 6.4; 95% confidence interval 3.6-11.3) and patients with persistent AF (hazard ratio 3.8; 95% confidence interval 2.2-6.6). Yet, in 29.4% of patients with paroxysmal AF and 34.3% of patients with persistent AF with ERAT, LRAT was not observed. LRAT was positively correlated with the number of ERAT observations.

CONCLUSION

ERAT after PFA predicted LRAT in patients with paroxysmal and persistent AF. However, the concept of a blanking period after PFA is still valid, as approximately one-third of patients with ERAT did not continue to have LRAT during follow-up and may not need reablation.

Impacts of Premature Atrial Contractions and Biochemical Markers Early After Cryoballoon Versus Radiofrequency Ablation on the Late Recurrence of Atrial Fibrillation

We sought to clarify the impacts of premature atrial contractions (PACs) and biochemical markers early after cryoballoon (CB) versus radiofrequency (RF) ablation for atrial fibrillation (AF) on the late recurrence of AF (LRAF). The study population included 138 patients who underwent first-time ablation for paroxysmal AF with CB (n = 69) or RF (n = 69). We compared the levels of the PAC burden on Holter monitoring, myocardial-bound creatine kinase (CK-MB), troponin T (TnT), and C-reactive protein (CRP) the day after ablation, and we assessed the incidence of LRAF, which was defined as AF after a 3-month blanking period. The postprocedural PAC burden was not significantly different between the CB and RF groups (P = .35), whereas the CK-MB and CRP levels were significantly higher in the CB group (both P < .01); the TnT levels of the groups were similar (P = .63). Among these, only a higher PAC burden was significantly associated with LRAF in both the CB (top quartile [≥2.16%]: 58% vs. others: 17%; log-rank P = .01) and RF (top quartile [≥3.05%]: 36% vs. others: 9%; log-rank P < .01) groups. A Cox regression analysis revealed two significant predictors of LRAF: in-hospital recurrence (CB group: hazard ratio [HR], 3.55 [1.67-11.80]; P = .04; RF group: HR, 7.55 [1.67-34.20]; P = .01) and a higher postprocedural PAC burden (CB: HR, 1.54 [1.06-2.22]; P = .02; RF: HR, 1.90 [1.16-3.35]; P = .01). In conclusion, irrespective of the ablation modality, the next-day PAC burden (but not the biochemical markers examined herein) is useful for predicting LRAF. Early AF recurrence should be considered a future risk even at the beginning of the blanking period.

Apolipoprotein and sphingolipid measurements: Can be used in the clinical practice of atrial fibrillation diagnosing and evaluating the cryoablation effectiveness?

Atrial fibrillation (AF) has become the most common arrhythmia of clinical importance. A well-established and recommended therapeutic option for AF is the balloon-based cryoablation (CBA) method. There are still no sensitive biomarkers for AF prediction and cryoablation effectiveness assessment, therefore in our prospective study, we examined the plasma content of apolipoproteins (Apo) and sphingolipids, as well as the distribution of selected sphingolipids among lipoprotein fractions. The study included 33 patients with AF on admission and 24 h after cryoablation therapy, while 20 healthy volunteers were recruited to the control group. Plasma Apo concentrations were determined using a multiplex assay kit measuring fluorescence signal, whereas the high-performance liquid chromatography (HPLC) method was applied to assess the total plasma sphingolipid levels as well as their content in isolated lipoprotein fractions. Our results showed that cryoballoon ablation in AF patients markedly reduced the level of almost all Apo compared to the individuals from the control and Pre-CBA groups (Apo-A1: -25.9% and -20.0%, Apo-A2: -19.9% and -17.3%, Apo-B: -26.8% and -14.4%, Apo-C1: -20.3% and -13.4%, Apo-D: -15.9% and -22.2%, Apo-E: -18.3% and -14.3%, and Apo-J: -36.4% and -21.5%, p < 0.05, respectively). Importantly, the area under the curve of Apo-J (AUC 0.81; 95% CI, 0.71-0.92) indicates that it might be a useful biomarker of cryotherapy success in AF patients. Moreover, we also observed a pronounced increase in sphinganine (Sa; +33.5%), sphingosine (So; +24.6%), sphinganine-1-phosphate (Sa1P; +34.3%), and sphingosine-1-phosphate (So1P; +22.3%) concentrations in the Pre-CBA group in comparison with controls. This is the first study that evaluates such a broad panel of Apo and sphingolipids in patients with AF undergoing the CBA procedure, however, to confirm whether any of these parameters could be a clinically useful biomarker for predicting AF or assessing the effectiveness of treatment, further research will be necessary due to limitations of the study.

Impact of combining ablation index-guided and very high-power short-duration ablation at posterior wall adjacent to esophagus during perioperative period on procedural factors

INTRODUCTION

The impact of combining ablation index (AI)-guided and very high-power short-duration (vHPSD) ablation on procedural factors at the posterior wall near the esophagus is unclear.

METHODS

Atrial fibrillation patients who underwent initial ablation using three-dimensional mapping were enrolled. Patients were classified into two groups: those who underwent only AI-guided pulmonary vein isolation (PVI) (AI group) and those who underwent vHPSD ablation at the posterior wall adjacent to the esophagus in addition to AI-guided PVI (AI + vHPSD group). Differences in myocardial injury, inflammation, procedural characteristics, and pulmonary vein (PV) reconnection patterns were assessed between the two groups.

RESULTS

This study included 167 patients (AI group, 83 patients; AI+vHPSD group, 84 patients). No significant differences in high-sensitive troponin I or changes in inflammatory markers between pre- and Postablation were observed in either group. Total application time and total application energy were significantly lower in the AI+vHPSD group than in the AI group (p < 0.001 for both) despite no significant difference in the total number of applications between the groups. The incidence of esophagus temperature ≥40 degrees was significantly lower in the AI+vHPSD group than in the AI group (p = 0.036). However, the incidence of PV reconnections near the esophagus was significantly higher in the AI+vHPSD group than in the AI group (11.9% vs 3.6%, p = 0.046), despite no significant difference in the incidence of PV reconnections overall.

CONCLUSION

The combination of AI-guided PVI and vHPSD adjacent to the esophagus demonstrated reduced application energy requirements and maintained safety and effectiveness during the perioperative period.

Prognostic Value of Burst Pacing Inducibility Post-Radiofrequency Versus Cryoablation for Paroxysmal Atrial Fibrillation

BACKGROUND

Atrial fibrillation (AF) inducibility with burst pacing (BP) after radiofrequency ablation (RFA) has been reported to be associated with AF recurrence. In contrast, the relevance of inducibility and recurrence after cryoablation (CRA) is unclear.

METHODS

We investigated 367 patients undergoing initial ablation for paroxysmal AF (RFA: 174, CRA: 193). Propensity score matching was conducted, retaining 134 patients in each group. Following pulmonary vein isolation (PVI), the inducibility by BP was tested. Inductions at 250 ppm were defined as low-frequency burst pacing (LFBP) positive, and those at 300 ppm were classified as medium-frequency burst pacing (MFBP) positive. They were followed for 600 days.

RESULTS

Forty-eight patients (18%) had AF recurrence. There was no significant difference in the recurrence rate between RFA and CRA (17% vs. 19%, Log-rank p = 0.79). In RFA, significant differences were observed for both LFBP (Log-rank p < 0.001) and MFBP (Log-rank p < 0.001). In contrast, in CRA, there were no significant differences for either LFBP (Log-rank p = 0.39) or MFBP (Log-rank p = 0.19). Multivariable analysis revealed that LFBP-positive (hazards ratio [HR] = 5.75, 95% confidence interval [CI] 2.41-13.7, p < 0.001) was an independent predictor for recurrence with RFA. Acute reconnection (HR = 2.73, 95% CI 1.13-6.56, p = 0.025) was an independent predictor for recurrence with CRA.

CONCLUSION

The inducibility by BP after RFA predicted recurrence at both low and medium frequencies. LFBP-positive was an independent predictor of recurrence in multivariable analysis. In contrast, the inducibility by BP after CRA was not a predictor of recurrence.

TRAIL REGISTRATION

This study did not require clinical trial registration.

Impact of different energy sources on coagulation biomarkers and silent cerebral events in balloon-based ablation for atrial fibrillation

Background

Different energy sources of balloon-based ablation for pulmonary vein isolation cause different kinds of endothelial damage and coagulation responses associated with thromboembolic risk.

Objectives

The study sought to compare the impact of different balloon-based ablation, cryoballoon ablation (CBA) and laser balloon ablation (LBA), on coagulation/fibrinolysis biomarkers and silent cerebral events (SCEs) in paroxysmal atrial fibrillation.

Methods

Paroxysmal atrial fibrillation patients who underwent pulmonary vein isolation using either CBA (n = 52) or LBA (n = 53) without radiofrequency touch-up ablation were eligible. Time course (day 0 [before ablation], day 1, day 2, and day 28) of myocardial enzymes and inflammatory and coagulation/fibrinolysis biomarkers was evaluated during the perioperative period. Brain magnetic resonance imaging was performed within 2 days after the procedure to evaluate SCEs.

Results

There was no difference in patient characteristics between CBA and LBA.CBA had greater myocardial injury (troponin I and creatine kinase-MB) and lower inflammatory reaction (white blood cell count and neutrophil/lymphocyte ratio) than LBA. The coagulation biomarkers maximally increased by day 2 and then decreased in both groups. In day 28, the serum prothrombin fragment 1+2 and D-dimer levels in LBA were significantly higher than the values in CBA. The fibrinolysis biomarker (plasmin-α2 plasmin inhibitor complex) did not increase after the procedure in either group. The incidence of SCEs was comparable between CBA and LBA (11% vs 15%; P = .591). No thromboembolic event was observed.

Conclusion

CBA and LBA had different effects on myocardial injury, inflammatory reaction, and coagulation activity but did not affect the incidence of thromboembolic events. LBA had significantly higher coagulation activity in day 28 and may require more careful postprocedural anticoagulation than CBA.

Identification of key differentially expressed immune related genes in patients with persistent atrial fibrillation: an integrated bioinformation analysis

OBJECTIVE

We aimed to investigate key differentially expressed immune related genes in persistent atrial fibrillation.

METHODS

Gene expression profiles were downloaded from Gene Expression Omnibus (GEO) using "GEO query" package. "limma" package and "sva" package were used to conduct normalization and eliminate batch effects, respectively. We screened out differentially expressed genes (DEGs) based on "limma" package with the standard of |log fold change (FC)| ≥ 1.5 and false discovery rate (FDR) < 0.05. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of DEGs were performed by "clusterProfler" package. We further applied LASSO to select key DEGs, and intersected key DEGs with immune related genes from ImmPort database. The ROC curve of each DEIRG was constructed to evaluate its diagnostic efficiency for AF.

RESULTS

A total of 103 DEGs we were screened out, of them, 48 genes were down-regulated and 55 genes were up-regulated. Result of functional enrichment analysis show that, most of DEGs were related to immune response, inflammation, and oxidative stress. Ultimately, CYBB, RORB, S100A12, and CHGB were determined as key DEIRGs, each of which displayed a favor efficiency for diagnosing persistent AF.

CONCLUSION

CYBB, RORB, S100A12, and CHGB were identified as key DEIRGs in persistent AF, and future studies are needed to further explore the underlying roles of CYBB, RORB, S100A12, and CHGB in persistent AF.

Global research progress on radiofrequency ablation in cardiology: A bibliometric analysis (2004-2023)

In recent years, significant advancements in radiofrequency ablation technology have notably enhanced arrhythmia treatment in cardiology. Technological advancements and increasing clinical adoption have made radiofrequency ablation a key therapy in improving life quality for patients with conditions like atrial fibrillation (AF). Consequently, there has been a marked increase in research output, underscoring the technology's significance and its potential in cardiology. Aims to comprehensively analyze cardiology's radiofrequency ablation research trends, identifying leading countries and institutions in international collaborations, key researchers' contributions, and evolving research hotspots. The study, based on the Web of Science Core Collection database, reviewed the literatures from 2004 to 2023. CiteSpace 6.2.R7 Basic was used for bibliometric analysis, which examined annual publication trends, international collaboration networks, key authors, leading research institutions, major journals, keyword co-occurrence and clustering trends. Analyzing 3423 relevant articles, this study reveals a consistent growth in cardiology radiofrequency ablation research since 2004. The analysis shows that the United States, Germany, and France hold central roles in the international collaboration network, with leading authors from premier US and European institutions. Keyword cluster analysis identifies "atrial flutter" and "ventricular tachycardia" as current research focal points. Cardiology radiofrequency ablation research shows a growth trend, led by the United States and European countries. Research hotspots are concentrated on the diverse applications of radiofrequency ablation technology and the treatment of AF. Future studies may increasingly focus on technological innovation and the deepening of clinical applications.

Comparison of Postprocedural P-Wave Vector Magnitude on 12-Lead Electrocardiogram Between Cryoballoon and Radiofrequency Ablation

Pulmonary vein isolation (PVI) causes changes in P-wave parameters. However, the difference in changes in P-wave parameters including P-wave vector magnitude (Pvm) between radiofrequency catheter ablation (RFCA) and cryoballoon ablation (CBA) remains unknown. Paroxysmal atrial fibrillation (PAF) patients who underwent only PVI were enrolled. Pvm was calculated by the square root of the sum of the squared P-wave amplitude in leads II and V6 and one-half of the P-wave amplitude in V2. The patients were divided into 2 groups: RFCA and CBA. ΔPvm was calculated as ΔPvm (mV) = (Pvm at pre-PVI)-(Pvm at post-PVI). The following factors were evaluated: (1) differences in the ΔPvm between the 2 groups, (2) relation between late arrhythmia recurrence and ΔPvm in RFCA and CBA groups, and (3) the impact of relevant factors on ΔPvm. The study population included a total of 426 patients with PAF (RFCA, 167 patients; CBA, 259 patients). ΔPvm was significantly larger in CBA than in RFCA (p <0.001). Kaplan-Meier analysis showed late arrhythmia recurrence was significantly higher in patients with low ΔPvm (<0.019 mV) than high ΔPvm (≥0.019 mV) in RFCA (Log-rank p <0.001), and low ΔPvm (<0.033 mV) than high ΔPvm (≥0.033 mV) in CBA (Log-rank p <0.001). Multiple regression analysis showed that CBA and heart rate change were independently and significantly associated with ΔPvm (p <0.001 and p <0.001, respectively). In conclusion, ΔPvm was significantly larger in CBA than RFCA during procedure. Low ΔPvm had a higher risk of late arrhythmia recurrence in RFCA and CBA.

Defining the blanking period, using continuous ECG monitoring, after cryoballoon pulmonary vein isolation

BACKGROUND

Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) ablation. A blanking period (BP) of 3 months is used in clinical trials and practice. However, the optimal BP duration after PVI remains undefined.

OBJECTIVE

The aim of this study was to objectively define, using continuous monitoring by an implantable loop recorder, the optimal BP duration after cryoballoon PVI.

METHODS

We enrolled consecutive patients who had cryoballoon PVI and an implantable loop recorder. We determined the time of the last confirmed episode of AF within the blanking period. This was then correlated with AF recurrence in the first year after ablation.

RESULTS

There were 210 patients (66 ± 9 years; 138 [66%] male; 116 [55%] paroxysmal AF; CHA2DS2-VASc score, 2.5 ± 1.6). We defined 4 distinct groups based on the last AF episode within the BP: no AF days 0-90 (n = 96 [46%]) and last AF 0-30 days (n = 46 [22%]), 31-60 days (n = 18 [9%]), and 61-90 days (n = 50 [24%]). After the 3-month BP, 101 (48%) patients had AF recurrence at 160 ± 86 days. Compared with patients with no AF in the BP, those with recurrent AF and AF burden >0% 30 days after ablation had a significantly greater AF recurrence during long-term follow-up (P = .001).

CONCLUSION

Our data show that the approximately one-third of patients in whom AF occurs and who have a burden of >0% after the first month that follows PVI are at significantly higher risk of long-term recurrent AF. We therefore suggest that the blanking period be limited to a month after cryoballoon PVI.

Association between triglyceride-glucose index trajectories and radiofrequency ablation outcomes in patients with stage 3D atrial fibrillation

BACKGROUND

This study investigates the relationship between triglyceride-glucose (TyG) index trajectories and the results of ablation in patients with stage 3D atrial fibrillation (AF).

METHODS

A retrospective cohort study was carried out on patients who underwent AF Radiofrequency Catheter Ablation (RFCA) at the Cardiology Department of the Fourth Affiliated Hospital of Zhejiang University and Taizhou Hospital of Zhejiang Province from January 2016 to December 2022. The main clinical endpoint was determined as the occurrence of atrial arrhythmia for at least 30 s following a 3-month period after ablation. Using a latent class trajectory model, different trajectory groups were identified based on TyG levels. The relationship between TyG trajectory and the outcome of AF recurrence in patients was assessed through Kaplan-Meier survival curve analysis and multivariable Cox proportional hazards regression model.

RESULTS

The study included 997 participants, with an average age of 63.21 ± 9.84 years, of whom 630 were males (63.19%). The mean follow-up period for the participants was 30.43 ± 17.75 months, during which 200 individuals experienced AF recurrence. Utilizing the minimum Bayesian Information Criterion (BIC) and the maximum Entropy principle, TyG levels post-AF RFCA were divided into three groups: Locus 1 low-low group (n = 791), Locus 2 low-high-low group (n = 14), and Locus 3 high-high group (n = 192). Significant differences in survival rates among the different trajectories were observed through the Kaplan-Meier curve (P < 0.001). Multivariate Cox regression analysis showed a significant association between baseline TyG level and AF recurrence outcomes (HR = 1.255, 95% CI: 1.087-1.448). Patients with TyG levels above 9.37 had a higher risk of adverse outcomes compared to those with levels below 8.67 (HR = 2.056, 95% CI: 1.335-3.166). Furthermore, individuals in Locus 3 had a higher incidence of outcomes compared to those in Locus 1 (HR = 1.580, 95% CI: 1.146-2).

CONCLUSION

The TyG trajectories in patients with stage 3D AF are significantly linked to the outcomes of AF recurrence. Continuous monitoring of TyG levels during follow-up may help in identifying patients at high risk of AF recurrence, enabling the early application of effective interventions.

Prognostic implication of early recurrence after cryoballoon ablation in patients with atrial fibrillation

BACKGROUND

It remains uncertain whether the implication of early recurrence and blanking period can be applied to patients with atrial fibrillation (AF) treated with cryoballoon ablation (CBA). We aimed to explore the prognostic value of early recurrence in patients with AF treated with CBA.

METHODS

We studied consecutive AF patients who were treated with CBA between April 2019 and September 2020 in two tertiary medical institutes and followed for up to 12 months. The endpoint was the late recurrence of atrial arrhythmia, including AF, atrial flutter, and atrial tachycardia, following a 90-day blanking period. Atrial arrhythmia during the blanking period was defined as early recurrence and was not considered as an endpoint.

RESULTS

This study included 406 patients with AF who underwent CBA. During the follow-up, 147 (36.2%) cases of late recurrence were observed. Of the 104 patients with early recurrence, 85 experienced late recurrence during follow-up. Early recurrence was associated with an increased risk of late recurrence in the univariate and multivariate analyses (P < 0.001). When we classified the patients into paroxysmal AF and persistent AF groups, early recurrence was still significantly associated with a higher risk of late recurrence (P = 0.005 and P < 0.001, respectively).

CONCLUSION

Early recurrence after CBA was an independent risk factor for late recurrence in all patients as well as in those with paroxysmal AF and persistent AF. Therefore, further prospective studies could be considered to verify the risks and benefits of early rhythm control in patients with early recurrence.

Myocardial injury and inflammation following pulsed-field ablation and very high-power short-duration ablation for atrial fibrillation

INTRODUCTION

Pulmonary vein isolation (PVI) using radiofrequency ablation (RFA) is an established treatment strategy for atrial fibrillation (AF). To improve PVI efficacy and safety, high-power short-duration (HPSD) ablation and pulsed-field ablation (PFA) were recently introduced into clinical practice. This study aimed to determine the extent of myocardial injury and systemic inflammation following PFA, HPSD, and standard RFA using established biomarkers.

METHODS

We included 179 patients with paroxysmal AF receiving first-time PVI with different ablation technologies: standard RFA (30-40 W/20-30 s, n = 52), power-controlled HPSD (70 W/5-7 s, n = 60), temperature-controlled HPSD (90 W/4 s, n = 32), and PFA (biphasic, bipolar waveform, n = 35). High-sensitivity cardiac troponin T (hs-cTnT), creatine kinase (CK), CK MB isoform (CK-MB), and white blood cell (WBC) count were determined before and after ablation.

RESULTS

Baseline characteristics were well-balanced between groups (age 63.1 ± 10.3 years, 61.5% male). Postablation hs-cTnT release was significantly higher with PFA (1469.3 ± 495.0 ng/L), HPSD-70W (1322.3 ± 510.6 ng/L), and HPSD-90W (1441.2 ± 409.9 ng/L) than with standard RFA (1045.9 ± 369.7 ng/L; p < .001). CK and CK-MB release was increased with PFA by 3.4-fold and 5.8-fold, respectively, as compared to standard RFA (p < .001). PFA was associated with the lowest elevation in WBC (Δ1.5 ± 1.5 × 109 /L), as compared to standard RFA (Δ3.8 ± 2.5 × 109 /L, p < .001), HPSD-70W (Δ2.7 ± 1.7 × 109 /L, p = .037), and HPSD-90W (Δ3.6 ± 2.5 × 109 /L, p < .001).

CONCLUSION

Among the four investigated ablation technologies, PFA was associated with the highest myocardial injury and the lowest inflammatory reaction.

Ratio of P-Wave Duration to P-Wave Amplitude and Left Atrial Remodeling: Insights from Electrophysiological Findings and Myocardial Injury After Cryoballoon Ablation

The impact of the P-wave morphology on clinical outcomes postcatheter ablation (post-CA) and recurrent arrhythmia characteristics or electrophysiologic findings in patients with paroxysmal atrial fibrillation (PAF) remains unclear. Patients with PAF who underwent cryoballoon ablation were enrolled. In 12-lead electrocardiography recorded within 1 month before CA, the P-wave duration (Pd) and P-wave vector magnitude (Pvm) (square root of the sum of the squared P-wave amplitude in leads II, V6, and one-half of the P-wave amplitude in V2) were measured and divided into 2 groups: patients with high and low Pd/Pvm based on a statistically calculated cut-off value. We evaluated the incidence of late recurrence of atrial fibrillation (LRAF), myocardial injury (high-sensitive troponin I), and the electrophysiologic findings in repeat ablation sessions. This study included 269 patients with PAF. The median follow-up duration was 697 days. The cut-off value of the Pd/Pvm for predicting LRAF was 740.7 ms/mV (area under the curve = 0.81, sensitivity = 58.2%, and specificity = 89.6%). Multivariable Cox proportional hazards analysis showed that high Pd/Pvm (>740.7 ms/mV) was significantly associated with LRAF (p <0.001). The high-sensitive troponin I level was significantly lower, and the ratio of DR-FLASH score >3 was significantly higher in those with high than low Pd/Pvm (p = 0.044 and p = 0.002, respectively). In the repeat ablation sessions, the Pd/Pvm in patients with atrial tachycardia-induced or spontaneously occurring during the repeat CA sessions was significantly higher than in those without (p = 0.009). There was a significant difference between the Pd/Pvm and low-voltage area (p <0.001). In conclusion, the Pd/Pvm is significantly associated with LRAF after cryoballoon ablation in patients with PAF and predicts left atrial low-voltage areas and atrial tachycardia inducibility.

Left atrial appendage peak flow velocity predicts improvement in mitral regurgitation after atrial fibrillation ablation

BACKGROUND

Mitral regurgitation (MR) is associated with an increased risk of developing atrial fibrillation (AF) and high AF recurrence ratio after ablation. Left atrial appendage (LAA) is involved in left atrium (LA) pressure modulation and LAA peak flow velocity (LAAV) is validated as an indicator of LA contractile and reservoir function. LA function is related to the MR pathology, but the relationship between LAAV and improvement in MR after ablation remains unknown.

METHODS

The present study included AF patients with moderate or severe MR from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry. We evaluated MR severity one-year post-ablation and assigned the patients based on MR improvement (at least a one-grade improvement in MR over one year) and investigated the impact of the relevant factors, including LAAV, on MR improvement.

RESULTS

This study population included a total of 289 patients [paroxysmal AF (PAF), 112 patients; persistent AF (PerAF), 177 patients]. Kaplan-Meier analysis demonstrated that the patients with MR improvement had a significantly lower risk of late arrhythmia recurrence than those without (log-rank p < 0.001). MR improvement was observed in 56.3 % (63/112) of PAF patients and 55.4 % (98/177) of PerAF patients. Multiple regression analysis showed that LAAV was an independent and significant determinant of MR improvement post-ablation in both PAF and PerAF patients (p = 0.037 and p = 0.018, respectively), in addition to age and hemoglobin in PerAF patients (p = 0.045 and p = 0.048, respectively).

CONCLUSION

LAAV can predict an improvement in MR after catheter ablation in both PAF and PerAF patients.

Comparison of myocardial injury and inflammation between ablation index-guided and conventional contact force-guided ablation in atrial fibrillation patients

PURPOSE

Ablation index (AI)-guided ablation improves the incidence of arrhythmia recurrence as compared to conventional contact force (CF)-guided ablation. The aim of this study was to elucidate the differences in the biomarkers associated with myocardial injury and inflammation between conventional CF-guided and AI-guided ablation.

METHODS

Atrial fibrillation (AF) patients who underwent pulmonary vein isolation (PVI) from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry were enrolled. We divided the patients into two groups: conventional CF-guided PVI (CF group) and AI-guided PVI (AI group). The differences in biomarkers associated with myocardial injury and inflammation, and long-term durability of PVI between the two groups were evaluated.

RESULTS

This study population included a total of 794 patients (CF-guided, 241 patients; AI-guided, 553 patients). Total application time was significantly shorter, and total application number was significantly smaller in AI than CF group. High-sensitive troponin I (hs-TnI) post-ablation was significantly higher in AI than CF group (p < 0.001), even after taking the total application number and total application time into consideration. No significant differences in inflammatory markers changes from pre- to post-ablation were observed between the two groups. AI-guided ablation was significantly associated with the hs-TnI post-ablation by multiple regression analysis. The PV reconnection ratio was significantly smaller in AI than CF group (p = 0.037).

CONCLUSIONS

AI-guided ablation had the ability to create larger lesions than CF-guided ablation despite no increase in inflammation and achieved the better PVI durability than that of CF-guided.

Utility of short-time electrocardiogram to assess risk for atrial arrhythmia recurrence: Impact of atrial premature beat occurrence 1 day after pulmonary vein isolation for atrial fibrillation

INTRODUCTION

Atrial premature beats (APBs) are the trigger for atrial fibrillation (AF). We sought to investigate the clinical significance of APB occurrence 1 day after pulmonary vein isolation (PVI) for AF using a short-time electrocardiogram.

METHODS

A total of 206 patients undergoing PVI for paroxysmal AF were included. Electrocardiogram recording for 100 consecutive beats was performed 1 day after PVI. The patients were divided into two groups: those with reproducible APBs (≥1 beat) during reassessment (APB group, n = 49) or those without (non-APB group, n = 157). Late recurrence was defined as atrial tachyarrhythmia recurrence 3-12 months after PVI. The impact of APB occurrence on outcomes was investigated.

RESULTS

Late recurrence occurred in 19 patients (9.2%). The presence of low-voltage areas, left atrial volume, and recurrence rate were higher in the APB group than in the non-APB group. In the APB group, the patients with recurrence had lower prematurity index (PI, coupling interval of APB/previous cycle length) compared to those without. Receiver-operating characteristic analysis revealed PI (<59.3) to be a predictive factor of recurrence (area under the curve: 0.733). The study subjects were then reclassified into three groups according to the absence of APB occurrence (n = 157), presence thereof with PI ≥ 59.3 (n = 33), and presence with PI < 59.3 (n = 16). The multivariate Cox models revealed that APB with PI < 59.3 was an independent predictor for recurrence (hazard ratio, 8.735; p < 0.001).

CONCLUSION

A short-time electrocardiogram enables risk assessment for arrhythmia recurrence, and APB with low PI 1 day after PVI is a powerful predictor.

Subclinical Dysfunction of Left Atrial Compliance after Cryoballoon versus Radiofrequency Ablation for Paroxysmal Atrial Fibrillation

It has been suggested that cryoballoon (CB) ablation for paroxysmal atrial fibrillation (PAF) may lead to more extensive left atrial (LA) injury than radiofrequency (RF) ablation; however, results are conflicting. We sought to address this issue using modern echocardiographic techniques estimating the LA function after successful CB and RF ablation for PAF. A total of 90 patients (66% males, mean age 57 ± 10 years) successfully treated (no AF recurrences confirmed in serial 4-7 day ECG Holter monitoring) with RF (51%) or CB (49%) ablation for PAF were retrospectively studied. Echocardiography with speckle tracking (STE) was performed before and 12 months after the procedure. The peak longitudinal LA strain (LAS) and strain rate (LASR) during the reservoir (r), conduit (cd), and contraction (ct) phases were measured in sinus rhythm. Analysis of covariance was applied to compare changes in the echocardiographic parameters over time with the baseline measurements as covariance and the type of ablation as the factor. The parallelism of the slopes of the covariance was tested. The LA diameter decreased (38.3 ± 4.1 mm vs. 36.8 ± 3.6 mm, p < 0.001) in the whole study group at 12 months after ablation. The LASRr and LASRcd increased (1.1 ± 0.3 s-¹ vs. 1.3 ± 0.3 s-¹, p < 0.001 and 1.1 ± 0.3 s-¹ vs. 1.2 ± 0.3 s-¹, p < 0.001, respectively) whereas other LA strain parameters remained unchanged in the whole study group at 12 months after ablation. In the analysis of LA function at 12 months after the procedure regarding the mode of ablation, the worsening of parameters reflecting LA compliance was observed in patients with better pre-served baseline values in the CB ablation subgroup. For baseline LAScd >28%, the difference ΔCB - ΔRF was -7.6 (11.7; -3.4), p < 0.001, and for baseline LAScd >16%, ΔCB - ΔRF was -1.8 (-3.2; -0.4), p = 0.014. The traditional Doppler-derived parameter e' showed the same trend-for baseline e' ≥12 cm/s, ΔCB - ΔRF was -1.7 (-2.8; -0.6), p = 0.003. We conclude that worsening of parameters reflecting LA compliance was observed 12 months after CB ablation compared to RF ablation for PAF in patients who underwent a successful procedure and had better-preserved baseline LA function. This might suggest subclinical dysfunction of LA after the CB ablation procedure. The clinical significance of these findings warrants further investigations.

Relationship between pre-procedural non-ischemic ST-segment depression and the clinical outcomes after catheter ablation in persistent atrial fibrillation patients

BACKGROUND

ST-segment depression suggests the presence of coronary artery disease (CAD) during sinus rhythm, but the clinical significance, including the outcomes after catheter ablation (CA), in atrial fibrillation (AF) patients remain unknown.

METHODS

The present study included persistent AF (PerAF) patients from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry who underwent an initial ablation and had no history of CAD. We assigned the patients based on the presence of ST-segment depression before CA and evaluated the impact of relevant factors on ST-segment depression and the relationship between ST-segment depression, including leads locations (anterior leads, inferior leads, and lateral leads) or depression type (upsloping, horizontal, and downsloping) or the degree of ST-segment depression and late recurrence of AF (LRAF).

RESULTS

This study population included a total of 551 patients of whom 189 had ST-segment depression. The median follow-up duration was 397 days and LRAF occurred in 195 patients. By multiple regression analysis, diabetes mellitus, hemoglobin, brain natriuretic peptide, left ventricular ejection fraction, and left atrial diameter were significant determinants of ST-segment depression before CA. Kaplan-Meier analysis demonstrated that the patients with ST-segment depression had a significantly greater risk of LRAF than those without (p < 0.001). Multivariate Cox proportional hazards analysis showed ST-segment depression was independently and significantly associated with a higher risk of LRAF (p < 0.001). The patients with ST-segment depression ≥0.15 mV had a significantly higher risk of LRAF than those with ST-segment depression ≥0.15 mV (p < 0.001). No significant differences among the ST-segment depression lead locations and ST-segment depression type were observed.

CONCLUSION

Non-ischemic ST-segment depression during AF rhythm was significantly associated with LRAF post CA in PerAF patients.

Evidence-based insights on ideal blanking period duration following atrial fibrillation catheter ablation

AIMS

Despite the general adoption of a 3-month blanking period (BP), increasing scientific evidence suggests an association between early recurrences of atrial tachyarrhythmias (ERAT) and failure of atrial fibrillation catheter ablation (AFCA). The aim of the present study was to perform a diagnostic meta-analysis to derive the ideal BP cut-off following AFCA.

METHODS AND RESULTS

PubMed/MEDLINE databases were screened for articles reporting late recurrences of atrial tachyarrhythmias (LRAT) in AFCA patients experiencing an ERAT (with at least one time cut-off). Seventeen studies were finally included in the analysis, encompassing 5837 AF patients experiencing ERAT after AFCA. A random-effect meta-analysis of diagnostic test accuracy studies with multiple cut-offs was performed. The day at which the ERAT occurred was considered the diagnostic 'test', whereas the different time cut-offs reported in the singular studies were treated as cut-offs of interest in the meta-analysis. Overall, a 27.7 day (95% confidence interval: 10.4-45.1 days) cut-off was identified as the optimal BP duration [area under the summary receiver operating characteristic (AUC-SROC) curve: 0.66, 95% CI: 0.56-0.75]. Specificity (95% CI: 63-85%) and positive predictive value were 76%. At subgroup analysis, the optimal BP cut-off was 39.0 days (95% CI: 26.8-51.2 days, AUC-SROC: 0.63) following radiofrequency AFCA and 30.1 days (95% CI: 0-63.4 days, AUC-SROC: 0.76) after cryoballoon ablation.

CONCLUSION

The present meta-analysis indicates that a 4-week BP represents the optimal cut-off following AFCA. Altogether, these meta-analytic insights support the need of a revision of the actual 3-month BP duration.

Evaluation of Isolation Area, Myocardial Injury and Left Atrial Function Following High-Power Short-Duration Radiofrequency or Second-Generation Cryoballoon Ablation for Atrial Fibrillation

This randomized study aims to compare the left atrial (LA) lesion size, function, and tissue damage following pulmonary vein isolation (PVI) by high-power short-duration (HPSD) radiofrequency (RF) and second-generation cryoballoon (CB2) ablation. We enrolled 40 patients with paroxysmal atrial fibrillation who underwent PVI by HPSD RF (n = 21) or CB2 (n = 19). Every patient underwent LA CT angiography and transthoracic echocardiography (TTE) to assess the LA anatomy and function. Biomarker levels (hs-cTnT, hs-CRP, LDH) were compared pre- and post-procedurally. Pre- and post-ablation high-density mapping (HDM) was performed. The isolation area was defined under 0.2 mV bipolar voltage (low voltage area, LVA). We calculated the post-PVI LVA/LA surface ratio using LA CT-HDM merge images. At 3-month follow-up, TTE was performed to assess the changes in LA function. Post-ablation hs-cTnT level was significantly higher in the RF group (RF: 1249 ± 469 ng/L, CB2: 995 ± 280 ng/L, p = 0.024). Post-PVI hs-CRP (RF: 9.53 ± 10.30 mg/L, CB2: 12.36 ± 5.76 mg/L, p = 0.034) and LDH levels (RF: 349.9 ± 65.6 U/L, CB2: 451.6 ± 91.3 U/L, p < 0.001) were significantly higher following CB2 ablation. Post-PVI LVA/LA surface ratios were 8.37 ± 6.42% in the RF group and 13.58 ± 8.92% in the CB2 group (p = 0.022). LA function did not change significantly after the PVI procedure. Our data indicate that second-generation cryoballoon ablation produces a significantly larger LA lesion size compared to “point-by-point” HPSD radiofrequency. Both techniques preserve LA function. The myocardial component of tissue loss appears to be higher using HPSD radiofrequency ablation, with less collateral damage.

Early recurrence after cryoballoon versus radiofrequency ablation for paroxysmal atrial fibrillation: mechanism and implication in long-term outcome

Background

Early recurrence (ER) after catheter ablation for atrial fibrillation (AF) has been considered as a common phenomenon but its mechanism and implication in long-term outcome has not been fully elucidated. We aimed to clarify the relation between post-ablation inflammation and ER after cryoballoon ablation (CBA) or radio-frequency ablation (RFA) and evaluate the clinical significance of ER.

Methods

A total of 154 patients with paroxysmal AF undergoing ablation were consecutively recruited, including 90 patients undergoing RFA (RF group) and 64 patients undergoing CBA (CB group). Myocardial injury and inflammation biomarkers were analyzed before and 6 h, 24 h and 48 h after ablation. Acute early recurrence (AER), non-acute early recurrence (NAER) and late recurrence (LR) was defined as recurrence of atrial tachyarrhythmia during 0–3, 4–90 days and beyond a 90-day blanking period after ablation.

Results

Cardiac troponin I was significantly higher in CB group while C reactive protein (CRP) and Ratio Neutrophil/Lymphocyte were more elevated in RF group. Higher CRP level after RFA was significantly associated with AER in RF group and lower CRP level after CBA was predictive of AER in CB group. In addition, average cryoablation duration was positively correlated with CRP level after CB group. Cox regression revealed that NAER and left atrial diameter were associated with LR in RF group, while AER and NAER were predictive of LR after CBA.

Conclusions

Post-ablation inflammation was greater in RFA than in CBA. Excessive inflammatory response may be an important factor of AER after RFA. AER after CBA was related with lower inflammation and predictive of LR. Further investigations are still warranted to address on these findings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-022-02816-1.

Impact of very early recurrence of atrial fibrillation after cryoballoon ablation

BACKGROUND

Although much has been discussed about the early recurrence of atrial fibrillation (ERAF) after cryoballoon ablation (CBA), the clinical impact of very early recurrence of atrial fibrillation (VERAF) after CBA remains unclear. This study aimed to investigate the impact of VERAF after CBA.

METHODS

We enrolled 236 consecutive patients who underwent an initial CBA for paroxysmal atrial fibrillation between February 2017 and December 2020 in our hospital. These patients were categorized into three groups: VERAF group who experienced an initial recurrence of atrial tachyarrhythmia within 48 hours after CBA, late-ERAF (LERAF) group who experienced an initial recurrence of atrial tachyarrhythmia between 48 hours and 3 months after CBA, and non-ERAF (NERAF) group who did not experience a recurrence of atrial tachyarrhythmia within 3 months after CBA. We investigated the late recurrence of AF (LRAF, defined as recurrence of atrial tachyarrhythmia more than 3 months after CBA), and the incidence of non-pulmonary vein (PV) triggers in the patients who experienced a repeat ablation procedure due to LRAF.

RESULTS

VERAF group had a higher incidence of freedom from LRAF than LERAF group (P = 0.032) and a lower incidence of freedom from LRAF than NERAF group (P = 0.002). Moreover, VERAF group had the highest incidence of non-PV triggers at repeat ablation procedure among the three groups (P = 0.003).

CONCLUSIONS

While ERAF was a predictor of LRAF, VERAF was less related to LRAF among the patients with ERAF after CBA. Furthermore, VERAF might be associated with non-PV triggers. This article is protected by copyright. All rights reserved.

Impact of cryoballoon contact angle and acute myocardial injury on pulmonary vein reconnection

At present, it remains unclear whether the effect on cryoinjury can be strongly exerted by contact of the balloon with the pulmonary vein (PV) ostium. The present study included 204 paroxysmal atrial fibrillation (PAF) patients who underwent an initial pulmonary vein isolation (PVI) using a cryoballoon from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry. The total balloon contact angle was measured from the equator line (sum of the angles of the upper side and bottom side in all PVs) under fluoroscopic imaging. The patients were stratified into three tertile groups according to the total balloon contact angle. We evaluated the relationship between the total balloon contact angle and clinical outcomes, including the value of acute myocardial injury marker (high-sensitive cardiac troponin I [hs-TnI]), arrhythmia recurrence, and PV reconnections in the repeated ablation. The total balloon contact angle was significantly associated with the hs-TnI value among the tertile groups (p < 0.001) and a multiple regression analysis showed that the total balloon contact angle significantly correlated with the hs-TnI value (standardized beta-coefficient = 0.572, p < 0.001). The balloon contact angle in PVs with PV reconnections was significantly lower than in those without (p = 0.044), while no significant differences in the recurrence of atrial fibrillation among the tertile groups were observed in the enrolled patients. The total balloon contact angle was significantly associated with the acute myocardial injury marker, hs-TnI. The total balloon contact angle was significantly associated with PV reconnections after cryoballoon ablation in patients who underwent a repeat ablation.

Visualization of thermal damage using 68 Ga-FAPI-PET/CT after pulmonary vein isolation

PURPOSE

68 Ga-fibroblast-activation protein inhibitor (FAPI) positron emission tomography (PET) is a novel technique targeting FAP-alpha. This protein is expressed by activated fibroblasts which are the main contributors to tissue remodeling. The aim of this proof-of-concept study was to assess 68 Ga-FAPI uptake in the pulmonary vein (PV) region of the left atrium after pulmonary vein isolation (PVI) with cryoballoon ablation (CBA) and radiofrequency (RFA) as a surrogate for thermal damage.

METHODS

Twelve PVI patients (5 RFA, 7 CBA) underwent 68 Ga-FAPI-PET 20.5 ± 12.8 days after PVI. Five patients without atrial fibrillation or previous ablation served as controls. Standardized uptake values of localized tracer uptake were calculated.

RESULTS

Focal FAPI uptake around the PVs was observed in 10/12 (83.3%) PVI patients, no uptake was observed in 2 PVI patients and all controls. Patients after PVI had higher FAPI uptake in PVs compared to controls (SUVmax: 4.3 ± 2.2 vs. 1.6 ± 0.2, p < 0.01; SUVpeak: 2.9 ± 1.4 vs. 1.3 ± 0.2, p < 0.01). All CBA patients had an intense uptake, while in the RFA, group 2 (40%), 1 (20%), and 2 (40%) patients had an intense, moderate, and no uptake, respectively. We observed higher uptake values (SUVpeak) in CBA compared to RFA patients (4.4 ± 1.5 vs. 2.5 ± 0.8, p = 0.02).

CONCLUSION

We demonstrate in-vivo visualization of 68 Ga-FAPI uptake as a surrogate for fibroblast activation after PVI. CBA seems to cause more pronounced fibroblast activation following tissue injury than RFA. Future studies are warranted to assess if this modality can contribute to a better understanding of the mechanisms of AF recurrence after PVI by lesion creation and gap assessment.

Clinical impact of right ventricular-pulmonary artery uncoupling on predicting the clinical outcomes after catheter ablation in persistent atrial fibrillation patients

Background

Right ventricular (RV)-pulmonary artery (PA) uncoupling is associated with poor outcomes in heart failure patients. We aimed to elucidate the relationship between RV-PA uncoupling and late arrhythmia recurrence after ablation in persistent atrial fibrillation (PerAF) patients whose phenotypes have impaired right ventricular function and pulmonary hypertension.

Methods

The present study included 203 PerAF patients from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry who underwent an initial ablation. We assigned the patients based on the value of tricuspid annular plane systolic excursion (TAPSE)/pulmonary artery systolic pressure (PASP) ratio that could predict late recurrence of AF/atrial tachycardia (LRAF) as an indicator of RV-PA uncoupling. We evaluated the following factors: the difference in the relationship between TASPE/PASP before ablation and incidence of LRAF among the 2 groups stratified by TAPSE/PASP based on the above cut-off value and TAPSE/PASP change from before to one-year after ablation.

Results

A receiver operating characteristic curve analysis revealed a good accuracy of predicting LRAF by TAPSE/PASP ratio with a cutoff of 0.57. The patients with TAPSE/PASP ratios ≤ 0.57 had a significantly greater LRAF risk than TAPSE/PASP ratios > 0.57. A multivariate Cox proportional hazards analysis showed that TAPSE/PASP (HR 0.12, 95% CI; 0.019–0.724, p = 0.026) was independently and significantly associated with LRAF. The TAPSE/PASP significantly improved more one-year after the ablation than before (p = 0.016).

Conclusion

RV-PA uncoupling was independently associated with LRAF, independent of left atrial function, and significantly improved more one-year after the ablation than before in PerAF patients.

Early arrhythmia recurrence after cryoballoon ablation in atrial fibrillation: a systematic review and meta-analysis

BACKGROUND

Early arrhythmia recurrence within the three-month blanking period is a common event that historically has been attributed to reversible phenomena. While its' mechanistic links remain obscure, accumulating evidence support the argument of shortening the blanking period. We aimed to elucidate the association between early and late arrhythmia recurrence after atrial fibrillation cryoablation.

METHODS

The MEDLINE database, ClinicalTrials.gov, medRxiv and Cochrane Library were searched for studies evaluating early and late arrhythmia recurrence rates in patients undergoing cryoablation for AF. Data were pooled by meta-analysis using a random-effects model. The primary endpoint was late arrhythmia recurrence.

RESULTS

Early arrhythmia recurrence was found predictive of decreased arrhythmia-free survival after evaluating 3975 patients with paroxysmal or persistent atrial fibrillation who underwent cryoablation (OR: 5.31; 95% CI: 3.75-7.51). This pattern remained unchanged after sub-analyzing atrial fibrillation type (paroxysmal; OR: 7.16; 95% CI: 4.40-11.65 and persistent; OR: 7.63; 95% CI: 3.62-16.07) as well as cryoablation catheter generation (first generation; OR: 5.15, 95% CI: 2.39-11.11 and advanced generation; OR: 5.83, 95% CI: 3.68-9.23). Studies permitting anti-arrhythmic drug utilization during blanking period or examining early recurrence as a secondary outcome were found to be a significant source of statistical heterogeneity.

CONCLUSION

Our findings suggest that early arrhythmia recurrence is predictive of late outcomes after cryoablation for atrial fibrillation. Identifying which patients deserve earlier re-intervention is an open research avenue. This article is protected by copyright. All rights reserved.

Acute myocardial injury after radiofrequency catheter ablation: impact on pulmonary vein reconnection and relevant factors

Radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) causes myocardial injury and induces high-sensitive cardiac troponin I (hs-TnI) release into the systemic circulation. Several factors are considered to be associated with myocardial injury after ablation, but few studies showed the relationship between the value of myocardial injury marker after the RFCA and relevant factors. AF patients who underwent primary RFCA were enrolled from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry. The relationship between hs-TnI after the RFCA and PV reconnection (PVR) was evaluated. The impact of relevant factors, including baseline patient characteristics, detail of procedure on myocardial injury was investigated. This study included 407 patients (median age was 71 years, the ratio of female was 30.7%). Late arrhythmia recurrence was observed in 111 patients (27.3%) and 66 patients were underwent repeated ablation. PVR was observed in 33 patients (50.0%). The hs-TnI level was significantly lower in the patients with PVR than those without PVR (1.150 ng/ml vs 1.921 ng/ml, p = 0.040). Paroxysmal AF and age were significantly associated with acute myocardial injury after the RFCA (standardized beta coefficient = 0.206 and p < 0.001, standardized beta coefficient = - 0.114 and p = 0.043, respectively). The hs-TnI after RFCA was significantly higher in PAF patients than PerAF (p < 0.001), even if application number and total application time were taken into consideration. Acute myocardial injury after RFCA was significantly lower in the patients with PVR than those without PVR. Age and AF type were significantly and strongly associated with acute myocardial injury after the RFCA.

Clinical impact of very early recurrence of atrial fibrillation after radiofrequency catheter ablation

BACKGROUND

Little has been reported on the impact of very early recurrence of atrial fibrillation (VERAF) after radiofrequency catheter ablation (RFCA).

METHODS

We enrolled 201 consecutive patients who underwent an initial RFCA of atrial fibrillation (AF) between September 2014 and April 2019 in our hospital and experienced early recurrence of AF (ERAF, defined as recurrence of atrial tachyarrhythmia within 3 months after RFCA). These patients were categorized into three groups: Group A who experienced recurrence of atrial tachyarrhythmia only within 48 h after RFCA, Group B who experienced recurrence of atrial tachyarrhythmia both within 48 h and between 48 h and 3 months after RFCA, and Group C who experienced the first recurrence of atrial tachyarrhythmia between 48 h and 3 months after RFCA. We compared the patient characteristics, ablation procedure and procedure-related complications, and clinical outcomes among the three groups. In addition, we investigated the pulmonary vein (PV) reconnections in the patients who experienced a repeat ablation procedure due to late recurrence of AF (LRAF, defined as recurrence of atrial tachyarrhythmia between 3 and 12 months after RFCA).

RESULTS

The Group A, B, and C consisted of 54, 40, and 107 patients, respectively. The inflammatory markers on the second day of RFCA were significantly higher in Group A. Moreover, Group A had a lower incidence of LRAF (p < 0.001) and PV reconnections at repeat ablation procedure (p = 0.023).

CONCLUSIONS

VERAF may have better clinical outcomes including lower incidence of LRAF and PV reconnections among patients with ERAF.

Impact of myocardial injury and inflammation due to ablation on the short-term and mid-term outcomes: Cryoballoon versus laser balloon ablation

BACKGROUND

Cryoballoon ablation (CBA) and laser balloon ablation (LBA) were developed as alternatives to conventional radiofrequency ablation for paroxysmal atrial fibrillation (PAF). Pathological findings after ablation such as myocardial injury and inflammation are thought to be different between CBA and LBA. However, the different impact of myocardial injury and inflammation after ablation on short- and mid-term outcomes remains unclear.

METHODS

Consecutive PAF patients who underwent CBA and LBA were enrolled from the Osaka Rosai Atrial Fibrillation ablation (ORAF) registry. The difference of the acute myocardial injury marker (hs-TnI), and changes of inflammation markers (C reactive protein; ΔCRP, and white blood cell; ΔWBC) after catheter ablation and the difference of the short-term (within 3 months after ablation) and mid-term (from 3 months to 6 months after ablation) outcomes were evaluated between the two groups.

RESULTS

The CBA and LBA groups consisted of 55 and 56 patients, respectively. After propensity score matching, CBA and LBA groups consisted of 37 patients, respectively. Hs-TnI value was significantly higher in CBA than LBA group, while ΔCRP and ΔWBC were significantly higher in LBA than CBA group. In the propensity score-matched pairs, the LBA group had a significantly greater risk of short-term arrhythmia recurrence than the CBA group, whereas no significant difference of mid-term arrhythmia recurrence were found between the two groups.

CONCLUSION

Myocardial injury and inflammation status differ between CBA and LBA groups. LBA group had stronger inflammation after ablation and had a significantly greater risk of short-term arrhythmia recurrence after PVI than CBA group.

Visualization of intensive atrial inflammation and fibrosis after cryoballoon ablation: PET/MRI and LGE-MRI analysis

BACKGROUND

Atrial inflammation plays an important role in initiating atrial fibrosis, which could perpetuate atrial fibrillation (AF). However, the method of visualization of atrial inflammation has not been established. We sought to investigate whether the intensive atrial inflammation caused by cryoballoon ablation (CBA) could be detected by positron emission tomography/ magnetic resonance imaging (PET/MRI) and whether the atrial inflammation could be associated with consequent fibrosis.

METHODS

A total of 10 paroxysmal atrial fibrillation patients after CBA were enrolled. To detect and quantify intensive atrial inflammation, PET/MRI was performed to assess regional 18F-fluorodeoxyglucose (18F-FDG) uptake one day after the CBA, and the standardized uptake values (SUV) max were compared between the pulmonary vein (PV) antrum where CBA could be applied and the healthy left atrial (LA) wall where CBA could not be applied. Furthermore, the atrial inflammation one day after the procedure and atrial fibrosis areas one month after the procedure were three-dimensionally quantified by PET/MRI and late-gadolinium enhancement magnetic resonance imaging (LGE-MRI), respectively.

RESULTS

The mean SUV max at the PV antrum was significantly higher than that on the healthy LA wall (2.12 ± 0.35 vs 1.73 ± 0.30, P = .00021). The volume of the atrial inflammation strongly correlated with that of the atrial fibrosis (r = .94 [.76-.99], P = .00006).

CONCLUSIONS

The atrial inflammation after CBA could be detected by PET/MRI. CBA-induced atrial inflammation was strongly associated with consequent lesion maturation.

Measurements of immature platelet fraction and inflammatory markers in atrial fibrillation patients - Does persistency or ablation affect results?

PURPOSE

Atrial fibrillation (AF) is associated with platelet hyperactivity and a higher proportion of immature platelets. We aimed to examine whether immature platelet fraction (IPF) and inflammatory markers differ between AF types and whether they are affected by ablation.

METHODS

A prospective study included patients with atrial fibrillation/flutter (AFL). We excluded patients with hematologic, inflammatory, or acute coronary states. Blood samples for IPF, white blood cells (WBC), neutrophil-to-lymphocyte ratio (NLR), and C-reactive protein (CRP) were collected at baseline, within one-hour postablation in those undergoing ablations, and the day after ablation. IPF was measured by an autoanalyzer (Sysmex 2100 XE).

RESULTS

One hundred and four patients were included (paroxysmal AF-63, persistent AF-36, AF and AFL-7, AFL alone-5), (Mean age 67.7 ± 12.8 years, 54.8% male, CHA₂ D₂ -VASC₂ 3.2 ± 1.8). Seventy-two patients underwent ablation (cryoballoon AF ablation-60, AFL radiofrequency ablation-5, both-7). There was no difference between paroxysmal and persistent AF regarding baseline markers. There was a significant change in the following parameters after ablation: WBC (baseline 6.9 ± 2.0, 1-h post 8.0 ± 2.4, and 1-day post 9.0 ± 2.8 ×10⁹ /L), NLR (2.9 ± 2.2, 3.0 ± 2.4, 4.2 ± 2.9, respectively), and CRP (3.6 ± 3.7, 3.6 ± 3.5, 12.4 ± 9.0 mg/L, respectively) (P < .05 for all). However, there were no differences in immature platelet count (8.6 ± 4.8, 8.5 ± 4.9, 8.4 ± 5.2 ×10⁹ /L) or IPF (4.6 ± 3.2, 4.7 ± 3.3, 4.9 ± 3.6%) from baseline to postablation (p = NS).

CONCLUSIONS

AF persistency does not affect IPF and inflammation. In patients undergoing cryoablation of AF, there is a postablation inflammatory process; however, platelet activation is probably not affected.

Atrial fibrillation type modulates the clinical predictive value of neutrophil-to-lymphocyte ratio for atrial fibrillation recurrence after catheter ablation

BACKGROUND

The neutrophil-to-lymphocyte ratio (NLR) has been proposed as an indicator of a systemic inflammatory response. There are baseline differences in the inflammation status between paroxysmal atrial fibrillation (PAF) and persistent AF (PerAF). The NLR changes and late recurrences of AF (LRAF) after ablation depending on the AF type remain unknown.

METHODS

Consecutive AF patients undergoing pulmonary vein isolation (PVI) by radiofrequency catheter ablation were enrolled from September 2014 to June 2018. The peripheral blood leukocyte NLR 1 day before and 36-48 h after PVI were measured. First, the relationship between NLR changes after to before ablation (ΔNLR) and ERAFs/LRAFs in PAF and PerAF patients were investigated to exclude the baseline inflammation status and evaluate catheter ablation induced inflammation. Second, the clinical impact of the NLR for predicting LRAFs was evaluated.

RESULTS

There hundred sixty-nine PAF and 264 PerAF patients from Osaka Rosai AF registry were enrolled. The ratio of ERAFs/LRAFs in PAF and PerAF patients were 26.8%/22.5% and 39.4%/29.9%, respectively. In PAF and PerAF patients, the ΔNLR was significantly higher with ERAF than no-ERAF (p = 0.022 and p = 0.010, respectively). In PAF patients, the ΔNLR was significantly higher with LRAF than no-LRAF (p = 0.017), while with PerAF, the ΔNLR did not significantly differ between LRAFs and no-LRAFs. In PAF, the ΔNLR was independently and significantly associated with LRAFs after PVI (p = 0.029).

CONCLUSION

The ΔNLR was significantly higher only in PAF patients with LRAFs than no-LRAFs, but not in PerAF patients. The ΔNLR was useful for predicting LRAFs after PVI in PAF patients.