Cellular damage, platelet activation, and inflammatory response after pulmonary vein isolation: A randomized study comparing radiofrequency ablation with cryoablation

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.

Atrial fibrillation progression after cryoablation vs. radiofrequency ablation: the CIRCA-DOSE trial

BACKGROUND AND AIMS

Atrial fibrillation (AF) is a chronic progressive disorder. Persistent forms of AF are associated with increased rates of thromboembolism, heart failure, and death. Catheter ablation modifies the pathogenic mechanism of AF progression. No randomized studies have evaluated the impact of the ablation energy on progression to persistent atrial tachyarrhythmia.

METHODS

Three hundred forty-six patients with drug-refractory paroxysmal AF were enrolled and randomly assigned to contact-force-guided RF ablation (CF-RF ablation, 115), 4 min cryoballoon ablation (CRYO-4, 115), or 2 min cryoballoon ablation (CRYO-2, 116). Implantable cardiac monitors placed at study entry were used for follow-up. The main outcome was the first episode of persistent atrial tachyarrhythmia. Secondary outcomes included atrial tachyarrhythmia recurrence and arrhythmia burden on the implantable monitor.

RESULTS

At a median of 944.0 (interquartile range [IQR], 612.5-1104) days, 0 of 115 patients (0.0%) randomly assigned to CF-RF, 8 of 115 patients (7.0%) assigned to CRYO-4, and 5 of 116 patients (4.3%) assigned to CRYO-2 experienced an episode of persistent atrial tachyarrhythmia (P = .03). A documented recurrence of any atrial tachyarrhythmia ≥30 s occurred in 56.5%, 53.9%, and 62.9% of those randomized to CF-RF, CRYO-4, and CRYO-2, respectively; P = .65. Compared with that of the pre-ablation monitoring period, AF burden was reduced by a median of 99.5% (IQR 94.0%, 100.0%) with CF-RF, 99.9% (IQR 93.3%-100.0%) with CRYO-4, and 99.1%% (IQR 87.0%-100.0%) with CRYO-2 (P = .38).

CONCLUSIONS

Catheter ablation of paroxysmal AF using radiofrequency energy was associated with fewer patients developing persistent AF on follow-up.

Severe acute kidney injury related to haemolysis after pulsed field ablation for atrial fibrillation

AIMS

Pulsed field ablation (PFA) has been proposed as a novel alternative to radiofrequency (RF) and cryoablation in the treatment of atrial fibrillation (AF). Following the occurrence of two cases of acute kidney injury (AKI) secondary to haemolysis after a PFA procedure, we evaluated haemolysis in a cohort of consecutive patients.

METHODS AND RESULTS

Two cases of AKI occurred in last May and June 2023. AKI was secondary to acute and severe haemolysis after a PFA procedure. From June 2023, a total of 68 consecutive patients (64.3 ± 10.5 years) undergoing AF ablation with PFA were enrolled in the study. All patients had a blood sample the day after the procedure for the assessment of haemolysis indicators. The pentaspline PFA catheter was used with a total number of median applications of 64 (54; 76). Nineteen patients (28%) showed significantly depleted haptoglobin levels (<0.04 g/L). A significant inverse correlation was found between the plasma level of haptoglobin and the total number of applications. Two groups were compared: the haemolysis+ group (haptoglobin < 0.04 g/L) vs. the haemolysis- group. The total number of applications was significantly higher in the haemolysis+ group vs the haemolysis - group respectively 75 (62; 127) vs 62 (54; 71) P = 0.011. More than 70 applications seem to have better sensitivity and specificity to predict haemolysis.

CONCLUSION

Intravascular haemolysis can occur after certain procedures of PFA. Acute kidney injury is a phenomenon that appears to be very rare after a PFA procedure. However, caution must be exercised in the number of applications to avoid severe haemolysis.

Effects of Inflammatory Cell Death Caused by Catheter Ablation on Atrial Fibrillation

Atrial fibrillation (AF) poses a serious healthcare burden on society due to its high morbidity and the resulting serious complications such as thrombosis and heart failure. The principle of catheter ablation is to achieve electrical isolation by linear destruction of cardiac tissue, which makes AF a curable disease. Currently, catheter ablation does not have a high long-term success rate. The current academic consensus is that inflammation and fibrosis are central mechanisms in the progression of AF. However, artificially caused inflammatory cell death by catheter ablation may have a significant impact on structural and electrical remodeling, which may affect the long-term prognosis. This review first focused on the inflammatory response induced by apoptosis, necrosis, necroptosis, pyroptosis, ferroptosis and their interaction with arrhythmia. Then, we compared the differences in cell death induced by radiofrequency ablation, cryoballoon ablation and pulsed-field ablation. Finally, we discussed the structural and electrical remodeling caused by inflammation and the association between inflammation and the recurrence of AF after catheter ablation. Collectively, pulsed-field ablation will be a revolutionary innovation with faster, safer, better tissue selectivity and less inflammatory response induced by apoptosis-dominated cell death.

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.

Plasma protein profiling analysis in patients with atrial fibrillation before and after three different ablation techniques

Background

There are controversies on the pathophysiological alteration in patients with atrial fibrillation (AF) undergoing pulmonary vein isolation using different energy sources.

Objectives

We evaluated the changes in plasma proteins in acute phase post-ablation in patients receiving cryoballoon ablation, radiofrequency balloon ablation, or radiofrequency ablation.

Methods

Blood samples from eight healthy controls and 24 patients with AF were taken on the day of admission, day 1, and day 2 post-ablation and analyzed by the Olink proximity extension assay. Proteins were identified and performed with enrichment analysis. Protein-protein interaction network and module analysis were conducted using Cytoscape software.

Results

Of 181 proteins, 42 proteins in the cryoballoon group, 46 proteins in the radiofrequency balloon group, and 43 proteins in the radiofrequency group significantly changed after ablation. Most of the proteins altered significantly on the first day after ablation. Altered proteins were mainly involved in cytokine-cytokine receptor interaction. Both balloon-based ablations showed a similar shift toward enhancing cell communication and regulation of signaling while inhibiting neutrophil chemotaxis. However, radiofrequency ablation presented a different trend. Seed proteins, including osteopontin, interleukin-6, interleukin-10, C-C motif ligand 8, and matrix metalloproteinase-1, were identified. More significant proteins associated with hemorrhage and coagulation were selected in balloon-based ablations by machine learning.

Conclusion

Plasma protein response after three different ablations in patients with AF mainly occurred on the first day. Radiofrequency balloon ablation shared similar alteration in protein profile as cryoballoon ablation compared with radiofrequency ablation, suggesting that lesion size rather than energy source is the determinant in pathophysiological responses to the ablation.

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.

Pilot study of peripheral blood chemokines as biomarkers for atrial fibrillation-related thromboembolism and bleeding in elderly patients

Background

The scoring systems currently used to identify the potential for thrombosis and bleeding events in high-risk atrial fibrillation patients have certain limitations. The aim of this pilot study was to identify inflammatory chemokines with potential utility as sensitive biomarkers for the risk of thrombosis and bleeding in elderly patients with non-valvular atrial fibrillation.

Methods

From January 1, 2014, to December 31, 2017, 200 consecutive elderly patients with atrial fibrillation (average age: 87.6 ± 7.7 years) were enrolled and followed up for 2 years to observe thromboembolic (arterial and venous) and bleeding events. Serum was collected upon enrollment, and the baseline levels of 27 chemokines were analyzed. During the 2-year follow-up, 12 patients were lost to follow-up. Among the 188 patients, there were 32 cases (17.0%) of AF-related thrombosis, 36 cases (19.1%) of arterial thrombosis, and 35 cases (18.6%) of major bleeding events.

Results

Among 188 patients, 30 patients without clinical events (control group), 23 with arterial thrombosis, 15 with atrial fibrillation-related venous thromboembolism, and 12 with major bleeding were selected and randomly matched to compare chemokine levels. The baseline levels of interleukin-6, interleukin-10, vascular cell adhesion molecule-1, chemokine C-C-motif ligand, B-lymphocyte chemoattractant 1, interleukin-4, E-selectin, fractalkine, C-X-C motif chemokine 12, and granulocyte chemotactic protein 2 were found to differ statistically among the four groups (p < 0.05). Compared with that in the control group, the level of interleukin-4 in patients with atrial fibrillation-related thrombosis, arterial thrombosis, or major bleeding increased by 53-fold (0.53 vs. 0.01 pg/ml), 17-fold (0.17 vs. 0.01 pg/ml), and 19-fold (0.19 vs. 0.01 pg/ml), respectively. Compared with that in the control group, the level of interleukin-6 in patients with arterial thrombosis increased by six-fold (39.78 vs. 4.98 pg/ml).

Conclusions

Among elderly patients with atrial fibrillation at high risk of thromboembolism and bleeding, the baseline levels of interleukin-6, interleukin-4, and E-selectin were significantly increased in those that experienced thrombosis and bleeding events during the 2-year follow-up, indicating that these chemokines may serve as potential biomarkers for an increased risk of thrombosis and bleeding in this population.

Clinical trial registration number

ChiCTR-OCH-13003479.

Extracellular Vesicles in Atrial Fibrillation—State of the Art

Extracellular vesicles are particles released from cells and delimited by a lipid bilayer. They have been widely studied, including extensive investigation in cardiovascular diseases. Many scientists have explored their role in atrial fibrillation. Patients suffering from atrial fibrillation have been evidenced to present altered levels of these particles as well as changed amounts of their contents such as micro-ribonucleic acids (miRs). Although many observations have been made so far, a large randomized clinical trial is needed to assess the previous findings. This review aims to thoroughly summarize current research regarding extracellular vesicles in atrial fibrillation.

Comparison of the Efficacy and Safety Endpoints of Five Therapies for Atrial Fibrillation: A Network Meta-Analysis

Introduction

Atrial fibrillation (AF) is a prevalent arrhythmia that occurs in 2–4% of adults and poses a threat to human health. Thus, comparison of the efficacy and safety of therapies for AF is warranted. Here, we used network analysis to compare efficacy (arrhythmia recurrence and re-hospitalization) and safety (ischemic cerebral vascular events, all-cause mortality, and cardiovascular mortality) endpoints among five major therapies for AF.

Methods

The PubMed, Cochrane, and Embase databases were searched, and relevant literature was retrieved. Only studies that made comparisons among the therapies of interest and involved patients with AF were included. Pairwise comparisons and frequentist method (SUCRA plot) analyses were conducted.

Results

In total, 62 studies were included in the pooled analysis. In pairwise comparisons, atrioventricular nodal ablation plus permanent pacemaker (AVN + PPM) was associated with a significantly higher risk of atrial arrhythmia recurrence than surgical ablation [odds ratio (OR): 23.82, 95% confidence interval (CI): 1.97–287.59, fixed-effect model; 3.82, 95% CI: 1.01–559.74, random-effects model]. Furthermore, radiofrequency ablation was associated with a significantly lower risk of cardiovascular mortality than medication in pairwise comparison (OR: 0.49, 95% CI: 0.29–0.83, fixed-effect model; OR: 0.49, 95% CI: 0.27–0.9, random-effects model). Frequentist analysis indicated that AVN + PPM had the best performance in reducing the risk of safety and efficacy endpoints.

Conclusion

Non-pharmaceutical therapies showed superior performance to traditional drug therapy in lowering the risk of safety and efficiency endpoint events. AVN + PPM performed best in reducing the risk of safety and efficacy endpoints.

The Blinding Period Following Ablation Therapy for Atrial Fibrillation: Proarrhythmic and Antiarrhythmic Pathophysiological Mechanisms

Atrial fibrillation (AF) causes heart failure, ischemic strokes, and poor quality of life. The number of patients with AF is estimated to increase to 18 million in Europe in 2050. Pharmacological therapy does not cure AF in all patients. Ablative pulmonary vein isolation is recommended for patients with drug-resistant symptomatic paroxysmal AF but is successful in only about 60%. In patients in whom ablative therapy is successful on the long term, recurrence of AF may occur in the first weeks to months after pulmonary vein ablation. The early recurrence (or delayed cure) of AF is not understood but forms the basis for the generally accepted 3-month blinding (or blanking) period after ablation therapy, which is not included in the evaluation of the eventual success rate of the procedures. The underlying pathophysiological processes responsible for early recurrence and the delayed cure are unknown. The implicit assumption of the blinding period is that the AF mechanism in this period is different from the ablation-targeted AF mechanism (ectopy from the pulmonary veins). In this review, we evaluate the temporary and long-lasting pro- and antiarrhythmic effects of each of the pathophysiological processes and interventions (necrosis, ischemia, oxidative stress, edema, inflammation, autonomic nervous activity, tissue repair, mechanical remodeling, and use of antiarrhythmic drugs) occurring in the blinding period that can modulate AF mechanisms. We propose that stretch-reducing ablation scar is a permanent antiarrhythmic mechanism that develops during the blinding period and is the reason for delayed cure.

Decrease in red cell distribution width as a useful predictor of success after catheter ablation for atrial fibrillation: a retrospective multi-center study

Red cell distribution width (RDW) is reportedly associated with cardiovascular events, including atrial fibrillation (AF). We investigated whether the RDW values were associated with the outcomes of catheter ablation for AF. This retrospective multicenter study included 501 patients with AF (239 paroxysmal AF cases, 196 persistent AF cases, and 66 long-standing persistent AF cases) who underwent initial AF ablation between March 2017 and May 2018. The RDW values were evaluated before and at 1-3 months after the procedure. The patients were stratified based on the recurrence of AF within 1 year after the index procedure with a blanking period of 3 months into recurrence group (107 patients, 21.4%) and no-recurrence group (394 patients, 78.6%). There were no significant differences in preoperative RDW values between the groups (p = 0.37). The RDW value did not change significantly after the ablation in the recurrence group (13.55-13.60%, p = 0.37), although it decreased significantly in the no-recurrence group (13.64-13.37%, p < 0.001). Multivariate Cox proportional hazards regression analyses revealed that a postoperative change in RDW (ΔRDW) was independently associated with AF recurrence (hazard ratio 2.00, 95% confidence interval 1.42-2.76, p < 0.001). Receiver operating characteristic curve analysis revealed that a ΔRDW cut-off value of - 0.1% provided a c-statistic of 0.65 for predicting AF recurrence. Decrease in RDW during the blanking period after ablation independently predicted the 1-year success of AF ablation.

The immediate trends in atrial electrical remodeling for paroxysmal atrial fibrillation across different modes of catheter ablation

Background

Catheter ablation has emerged as a major strategy for paroxysmal atrial fibrillation (PAF). Atrial electrical remodeling (AER) plays a critical role in the recurrence of PAF after ablation.

Hypothesis

To characterize the immediate trends of AER during ablations in patients with PAF, and assess the relationship between immediate trends and recurrence.

Methods

We performed this prospective observational study of 135 patients to investigate AER following three ablation modes: radiofrequency ablation (RFA), cryoablation (CA) and 3D mapping‐guided cryoablation (3D‐CA). The atrial effective refractory period (AERP) and atrial conduction time (ACT) were measured via electrophysiology before and immediately after ablation, and P‐wave indices were measured via electrocardiography before and within 24 h after ablation. Follow‐up visits were conducted for at least 1 year or until relapse.

Results

Different approaches of ablation caused a fairly significant increase in the shortest P‐wave duration and AERP in both the proximal coronary sinus (PCS) and distal coronary sinus (DCS) but caused a shortened P‐wave dispersion. No different effect was found at the AERP among the three modes. Compared to patients who received CA, among patients who received RFA, a significant reduction in total ACT and right ACT was seen. Statistically, there was a weakly positive association between changes in total ACT and early recurrence.

Conclusions

Injury during ablation for PAF was associated with an increase in the AERP but not in the ACT. Total ACT and right ACT were shorter after RFA than after CA. The increase in total ACT were slightly predictive of early recurrence.

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.

Comparative efficacy and safety of catheter ablation interventions for atrial fibrillation: comprehensive network meta-analysis of randomized controlled trials

PURPOSE

Point-by-point radiofrequency (RF) ablation has been the cornerstone of pulmonary vein isolation (PVI) for patients with atrial fibrillation (AF); however, it remains a complex and time-consuming procedure. Many novel AF catheter ablation (CA) techniques have been introduced, but whether they represent valuable alternatives remains controversial. Thus, we conducted a network meta-analysis to comprehensively evaluate the efficacy and safety of different CA interventions.

METHODS

We systematically searched several databases (Embase, PubMed, the Cochrane Library, and ClinicalTrials.gov ) from inception to March, 2020. The primary outcomes of interest were freedom from atrial tachyarrhythmia (AT) and procedure-related complications; secondary outcomes included procedure time and fluoroscopy time.

RESULTS

Finally, 33 randomized controlled trials (RCTs) with a total of 4801 patients were enrolled. No significant differences were found among the different interventions in terms of primary efficacy or safety outcomes. PVAC was most likely to have the shortest procedure time (Prbest = 61.5%) and nMARQ the shortest fluoroscopy time (Prbest = 60.6%); compared with conventional irrigated RF (IRF) ablation, cryoballoon ablation (CBA) showed comparable clinical efficacy and safety; CBA with second-generation CB (CB2) had a significantly shorter procedure time than IRF with contact force technology (CF-IRF) (WMD = - 20.75; p = 0.00).

CONCLUSION

There is insufficient evidence to suggest that one CA technique is superior to another. However, PVAC may be associated with a shorter procedural duration, and the CB2 catheters also seemed to reduce the procedure time compared with that of CF-IRF. Further large-scale studies are warranted to compare the available CA techniques and provide an up-to-date optimum recommendation.

Systematic review and network meta-analysis of atrial fibrillation percutaneous catheter ablation technologies using randomized controlled trials

AIMS

We sought out to make comparisons between all atrial fibrillation (AF) catheter ablation technologies using randomized controlled trial data. Our comparisons were freedom from AF, procedural duration, and fluoroscopy duration.

METHODS

Searches were made of EMBASE, MEDLINE, and CENTRAL databases, and studies were selected which had cryoballoon, conventional radiofrequency (RF), multipolar RF catheters, and laser technology as an arm in the study and were identified as randomized controlled trials (RCTs). These studies were analyzed for direct comparisons using conventional meta-analysis and a combination of indirect and direct comparisons via a network meta-analysis (NMA).

RESULTS

With respect to freedom from AF both direct comparisons and NMA did not demonstrate any significant difference. However in analysis of procedural and fluoroscopy duration (minutes) for the pulmonary vein ablation catheter (PVAC), both conventional analysis and NMA revealed significantly shorter procedure times, RF vs PVAC (conventional: 61.99 [38.03-85.94], P <.00001; NMA: 54.76 [36.64-72.88], P < .0001) and fluoroscopy times, RF vs PVAC (conventional: 12.96 [6.40-19.53], P = .0001; NMA: 8.89 [3.27-14.51], P < .01). The procedural duration was also shorter for the cryoballoon with NMA, RF vs CRYO (20.56 [3.47-37.65], P = .02).

DISCUSSION

Our analysis demonstrated that while there was no difference in the efficacy of the individual catheter technologies, there are significant differences in the procedural duration for the PVAC and the cryoballoon. While they may seem an attractive solution for high-volume centers, further RCTs of next-generation technologies should be examined.

Impact of left atrial appendage closure on circulating microvesicles levels: The MICROPLUG study

BACKGROUND

Left atrial appendage occlusion (LAAO) has emerged as a valid alternative to oral anticoagulation therapy for the prevention of systemic embolism in patients with non-valvular atrial fibrillation (NVAF). Microvesicles (MVs) are shed-membrane particles generated during various cellular types activation/apoptosis that carry out diverse biological effects. LAA has been suspected to be a potential source of MVs during AF, but the effects its occlusion on circulating MVs levels are unknown.

METHODS

N = 25 LAAO and n = 25 control patients who underwent coronary angiography were included. Blood samples were drawn before and 48 h after procedure for all. A third sample was collected 6 weeks after procedure in LAAO patients. In N = 10 extra patients, samples were collected from right atrium, LAA and pulmonary vein during LAAO procedure. Circulating AnnV + procoagulant, endothelial, platelets, red blood cells/RBC and leukocytes derived-MVs were measured using flow cytometry methods.

RESULTS

In the LAAO group, AnnV+, platelets, RBC, and leukocytes MVs were significantly increased following intervention, whereas only AnnV + MVs levels significantly rose in controls. The 6-w analysis showed that RBC-MVs and AnnV + MVs levels were still significantly elevated compared to baseline values in LAAO patients. The in-site analysis revealed that leukocytes and CD62e + endothelial-MVs were significantly higher in left atrial appendage compared to pulmonary vein, suggesting a local increased production. No major adverse event was observed in any patient post procedural course.

CONCLUSIONS

LAAO impacts circulating MVs and might create mild pro-coagulant status and potential erythrocytes activation due to the device healing during the first weeks following intervention.

Meta-Analysis Comparing Cryoballoon Versus Radiofrequency as First Ablation Procedure for Atrial Fibrillation

Pulmonary vein isolation is the cornerstone of atrial fibrillation (AF) ablation. Radiofrequency (RF) represents a standard of care for pulmonary vein isolation, whereas cryoballoon (CB) ablation has emerged as a valid alternative. The aim of our meta-analysis was to explore the efficacy and safety of CB compared with RF as first ablation procedure for AF. We searched the literature for studies that investigated this issue. The primary efficacy outcome was AF recurrence. The safety outcomes were: pericardial effusion, cardiac tamponade, phrenic nerve palsy, vascular complications, and major bleedings. Fourteen randomized controlled studies and 34 observational studies were included in the analysis. A total of 7,951 patients underwent CB ablation, whereas 9,641 received RF ablation. Mean follow-up was 14 ± 7 months. Overall, CB reduced the incidence of AF recurrence compared with RF ablation (relative risk [RR] 0.86; 95% confidence interval [CI] 0.78 to 0.94; p = 0.001), and this result was consistent across different study design and AF type. CB had a significantly higher rate of phrenic nerve palsy, whereas it was related to a lower incidence of pericardial effusion, cardiac tamponade (RR 0.58; 95% CI 0.38 to 0.88; p = 0.011) and vascular complications (RR 0.61; 95% CI 0.48 to 0.77; p <0.001) compared with RF. There was no significant difference in major bleedings between the 2 strategies. CB ablation had a shorter procedural time compared with RF (mean difference -20.76 minutes; p <0.001). In conclusion, considered its efficacy/safety profile and short procedural time, CB ablation represents the preferable option for first AF ablation procedure.

Cryoballoon ablation for pulmonary vein isolation

Over the past 20 years, multiple studies have demonstrated the superiority of percutaneous catheter-based pulmonary vein isolation (PVI) in the management of atrial fibrillation (AF). Unfortunately, the results of catheter ablation can be limited by arrhythmia recurrence, which is often a result of a failure to achieve durable lesions around the pulmonary vein ostia. In response, significant efforts have been directed toward developing technologies to achieve safer and more durable PVI, including the development of dedicated catheters capable of achieving PVI with a single ablation lesion (eg, the Arctic Front Cryoballoon; Medtronic CryoCath, Pointe-Claire, Canada). The purpose of this review is to discuss the contemporary role of cryoballoon ablation in the invasive management of AF, with a focus on the characteristics that differentiate cryoballoon from radiofrequency ablation.

Intracardiac Fibrinolysis and Endothelium Activation Related to Atrial Fibrillation Ablation with Different Techniques

Objective

The effect of pulmonary vein isolation (PVI) on fibrinolytic and endothelial activation with currently applied periprocedural anticoagulation has not been explored. We measured markers of fibrinolysis and endothelium activation before and after PVI with the second-generation cryoballoon (Cryo), pulmonary vein ablation catheter (PVAC-Gold), and irrigated radiofrequency (IRF).

Methods

Markers of fibrinolysis and endothelium activation in left atrial (LA) blood samples were measured in 31 patients before and after PVI (Cryo:10, PVAC-Gold: 7, IRF: 14). Periprocedural anticoagulation included uninterrupted vitamin K antagonist and iv heparin (ACT≥300 sec) during LA dwelling.

Results

Levels of D-dimer (median; interquartile range, mgFEU/L) increased with all techniques (PVAC: 0.34; 0.24–0.50 versus 0.70; 0.61–1.31; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; PAP complex level (ng/ml) increased after Cryo (247.3, 199.9–331.6 versus 270.9, 227.9–346.7; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; PAI-1 activity (%) decreased with the PVAC (1.931; 0.508–3.859 versus 0.735, 0.240–2.707; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; VWF antigen levels and FVIII activity increased after PVI with all the 3 techniques. The levels of soluble VCAM-1 (ng/ml) did not change after PVAC procedures, but increased after Cryo (542, 6; 428.5–753.1 versus 619.2; 499.8–799.0; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93; p=0.0313, Cryo: 0.33; 0.28–0.49 versus 0.79; 0.65–0.93;

Conclusion

PVI with contemporary ablation techniques and periprocedural antithrombotic treatment induces coagulation and endothelium activation of similar magnitude with different ablation methods.

Cryoballoon Ablation for the Treatment of Atrial Fibrillation: A Meta-analysis

BACKGROUND

Ablation therapy is the treatment of choice in antiarrhythmic drugrefractory atrial fibrillation (AF). It is performed by either cryoballoon ablation (CBA) or radiofrequency ablation. CBA is gaining popularity due to simplicity with similar efficacy and complication rate compared with RFA. In this meta-analysis, we compare the recurrence rate of AF and the complications from CBA versus RFA for the treatment of AF.

METHODS

We systematically searched PubMed for the articles that compared the outcome of interest. The primary outcome was to compare the recurrence rate of AF between CBA and RFA. We also included subgroup analysis with complications of pericardial effusion, phrenic nerve palsy and cerebral microemboli following ablation therapy.

RESULTS

A total of 24 studies with 3527 patients met our predefined inclusion criteria. Recurrence of AF after CBA or RFA was similar in both groups (RR: 0.84; 95% CI: 0.65, 1.07; I2=48%, Cochrane p=0.16). In subgroup analysis, heterogeneity was less in paroxysmal AF (I2=0%, Cochrane p=0.46) compared to mixed AF (I2=72%, Cochrane p=0.003). Procedure and fluoroscopy time was less by 26.37 and 5.94 minutes respectively in CBA compared to RFA. Complications, pericardial effusion, and silent cerebral microemboli, were not different between the two groups, however, phrenic nerve palsy was exclusively present only in CBA group.

CONCLUSION

This study confirms that the effectiveness of CBA is similar to RFA in the treatment of AF with the added advantages of shorter procedure and fluoroscopy times.

Data for short and long-term prothrombotic biomarkers after cryoballoon and radiofrequency ablation

Data presented in this article are supplementary analyzed tables and individual raw data to our research article entitled "Short and long-term changes in platelet and inflammatory biomarkers after cryoballoon and radiofrequency ablation (Bin Waleed K et al., 2019) [1]". These supplementary analyzed tables and individual raw data included platelet activation biomarkers [P-selectin (CD62P), CD40 ligand (CD40L), platelet factor-4 (PF-4), mean platelet volume (MPV), platelet-leukocyte ratio (P-LCR), and platelet distribution width (PDW)]; and inflammatory biomarkers [high sensitivity CRP (hs-CRP) and interleukin-6 (IL-6)] after cryoballoon (CB) and radiofrequency (RF) ablation. The provided raw data are intended to show the difference at short and long-term in platelet and inflammatory biomarkers values between CB and RF ablation.

A Cost-Utility Analysis of Cryoballoon Ablation versus Radiofrequency Ablation for Paroxysmal Atrial Fibrillation

Introduction

The objective of this study was to evaluate the cost-effectiveness of the treatment with cryoballoon (CB) compared to the standard treatment with traditional irrigated radiofrequency (RF) ablation for pulmonary vein isolation in patients with paroxysmal atrial fibrillation (pAF) refractory to antiarrhythmic drug therapy.

Methods

A decision tree model was developed to graphically depict the probabilities, utilities and costs of CB compared to RF therapy. Data from a conducted systematic literature review and meta-analysis of only RCTs were used to evaluate clinical outcomes of CB and RF treatments, including success rates after one year, complications and recurrence of atrial fibrillation.

Results

The cost-utility analysis estimated that, CB therapy had £1,747 higher cost, and 0.0114 more quality-adjusted life years (QALYs) compared to standard RF treatment over a one-year time horizon. The incremental cost per QALY of CB ablation compared to RF ablation was estimated to be £152,836/QALY.

Conclusions

Based on current evidence, CB ablation for pulmonary vein isolation in patients with pAF is costeffective compared to RF if decision makers are willing to pay £152,836 or higher for a QALY.

High-sensitive cardiac troponin T as a predictor of efficacy and safety after pulmonary vein isolation using focal radiofrequency, multielectrode radiofrequency and cryoballoon ablation catheter

Introduction

Myocardial injury markers such as high-sensitive cardiac troponin T (hs-cTnT) and creatine kinase MB (CK-MB) reflects the amount of myocardial injury with ablation. The aim of the study was to identify the value of myocardial injury markers to predict outcomes after pulmonary vein isolation (PVI) using three different ablation technologies.

Methods

Consecutive patients undergoing PVI using a standard 3.5 mm irrigated-tip radiofrequency catheter (RF-group), an irrigated multielectrode radiofrequency catheter (IMEA-group) and a second-generation cryoballoon (CB-group) were analysed. Blood samples to measure injury markers were taken before and 18–24 hours after the ablation. Procedural complications were collected and standardised follow-up was performed. Logistic regression was used to identify predictors of recurrence and complications.

Results

96 patients (RF group: n=40, IMEA-group: n=17, CB-group: n=39) undergoing PVI only were analysed (82% male, age 59±10 years). After a follow-up of 12 months, atrial fibrillation (AF) recurred in 45% in the RF-group, 29% in the IMEA-group and 36% in the CB-group (p=0.492). Symptomatic pericarditis was observed in 20% of patients in the RF-group, 15% in the IMEA-group and 5% in the CB-group (p=0.131). None of the injury markers was predictive of AF recurrence or PV reconnection after a single procedure. However, hs-cTnT was identified as a predictor of symptomatic pericarditis (OR: 1.003 [1.001 to 1.005], p=0.015).

Conclusion

Hs-cTnT and CK-MB were significantly elevated after PVI, irrespective of the ablation technology used. None of the myocardial injury markers were predictive for AF recurrence or PV reconnection, but hs-cTnT release predicts the occurrence of symptomatic pericarditis after PVI.

Effect of cryoballoon and radiofrequency ablation for pulmonary vein isolation on left atrial function in patients with nonvalvular paroxysmal atrial fibrillation: A prospective randomized study (Cryo-LAEF study)

BACKGROUND

Isolation of the pulmonary veins (PVI) has become a mainstay in atrial fibrillation (AFib) therapy. Lesions in left atrial tissue lead to scar formation and this may affect left atrial function.

METHODS

Patients with paroxysmal AFib were randomly assigned in a 1:2 allocation scheme to radiofrequency (RF) ablation or cryoballoon. Real-time three-dimensional echocardiography was performed (under sinus rhythm in all cases) before ablation and at 1 and 3 months to evaluate the left atrial functional indices. The primary outcome measure was change in left atrial ejection fraction (LAEF) at 1 month.

RESULTS

120 patients were randomized (80 to cryoballoon, 40 to RF). The absolute change in LAEF at 1 month was 4.0 (Q1-Q3, -0.1to 7.6)% in the cryoballoon group and -0.8 (Q1-Q3, -1.9 to 0.9)% in the RF group (P < 0.001 for the comparison between groups). At 3 months, the corresponding changes were 6.7 (Q1-Q3, 3.4-11.2)% and 0.7 (Q1-Q3, -0.7 to 3.5)%, respectively (P < 0.001). Overall, the rate of patients with lower LAEF at 3 months compared to baseline was 2.5% in the cryoballoon group and 32.5% in the RF group (P < 0.001). AFib recurrence rate at 6 months was higher in patients with decreased LAEF (odds ratio, 6.2; 95% confidence interval, 2.0-19.5; P = 0.002).

CONCLUSION

The Cryo-LAEF study prospectively compared the effects of RF and cryoballoon ablation on left atrial function. Both at 1 and 3 months postablation, LAEF was either improved or stable in both ablation groups.

Blood platelet and serum bilirubin in the diagnosis of central serous chorioretinopathy

Diagnostic value of blood platelet (PLT) and serum total bilirubin (TBIL) for central serous chorioretinopathy (CSC) was investigated. A total of 537 patients with CSC and 182 people with normal physical conditions were selected from June 2012 to August 2016. The 537 patients included 294 males and 243 females with an average age of 45.5±17.8 years, and all patients were treated in the Department of Ophthalmology of Yantai Hospital of Traditional Chinese Medicine and the Department of Ophthalmology of Yantai Liuhuangding Hospital. Clinical data of the patients were retrospectively analyzed. The 182 people with normal physical conditions included 103 males and 79 females with an average age of 43.6±15.2 years, and they were set as the control group. PLT and TBIL tests at admission and after treatment were collected and compared between CSC and the control group to analyze the diagnostic values of PLT and TBIL for CSC. PLT level in the CSC group was significantly higher than that in the control group, but TBIL level in the CSC group was significantly lower than that in the control group (p<0.05). Linear correlation analysis showed that PLT was a risk factor for CSC, and TBIL was a protective factor for CSC. The sensitivity of PLT and TBIL in diagnosis of CSC was 75.2 and 72.7%, respectively, and the specificity of PLT and TBIL in diagnosis of CSC was 65.8 and 63.3%, respectively. PLT of CSC patients was significantly higher than that of the control group, and TBIL of CSC patients was significantly lower than that of the control group, but they both gradually reduced to normal levels after treatment, which can be regarded as the index for the clinical diagnosis of CSC in the future.

[Biomarkers and atrial fibrillation : Prediction of recurrences and thromboembolic events after rhythm control management]

Atrial fibrillation (AF) is the most common arrhythmia in clinical praxis and is associated with an increased risk for cardio- and cerebrovascular complications leading to an increased mortality. Catheter ablation represents one of the most important and efficient therapy strategies in AF patients. Nevertheless, the high incidence of arrhythmia recurrences after catheter ablation leads to repeated procedures and higher treatment costs. Recently, several scores had been developed to predict rhythm outcomes after catheter ablation. Biomarker research is also of enormous interest. There are many clinical and blood biomarkers pathophysiologically associated with AF occurrence, progression and recurrences. These biomarkers-including different markers in blood (e. g. von Willebrand factor, D‑dimer, natriuretic peptides) or urine (proteins, epidermal grown factor receptor) but also cardiac imaging (echocardiography, computed tomography, magnetic resonance imaging)-could help to improve clinical scores and be useful for individualized AF management and optimized patients' selection for different AF treatment strategies. In this review, the role of diverse biomarkers and their predictive value related to AF-associated complications are discussed.

Radiofrequency Ablation versus Cryoablation in the Treatment of Paroxysmal Atrial Fibrillation: A Meta-Analysis

Background

Pulmonary vein isolation is commonly performed using radiofrequency energy with cryoablation gaining acceptance. We performed a meta-analysis of randomized controlled trials which compared radiofrequency versus cryoablation for patients with atrial fibrillation.

Methods

A systematic search strategy identified both published and unpublished articles from inception to November 10, 2016, in multiple databases. The primary outcomes for this meta-analysis were long-term freedom from atrial fibrillation at 12-month follow-up and overall postoperative complication rates. For all included studies, the methodological quality was assessed through the Cochrane Collaboration's tool for risk of bias.

Results

A total of 247 articles were identified with eight being included in this review as they satisfied the prespecified inclusion criteria. Overall, there was no significant difference in freedom from atrial fibrillation at ≥12-month follow-up between those receiving cryoballoon and radiofrequency ablation, respectively (OR = 0.98, CI = 0.67–1.43, I² = 56%, p=0.90). Additionally, the secondary outcomes of duration of ablation, fluoroscopy time, and ablation time failed to reach significance. Cryoballoon ablation had significantly greater odds of postoperative phrenic nerve injury at 12-month follow-up.

Conclusions

Our meta-analysis suggests that cryoballoon ablation provides comparable benefits with regard to freedom from atrial fibrillation at medium-term follow-up, fluoroscopy time, ablation time, operative duration, and overall complication rate in comparison to radiofrequency ablation.

Cryoballoon vs. radiofrequency ablation for paroxysmal atrial fibrillation: an updated meta-analysis of randomized and observational studies

Aims

Radiofrequency (RF) ablation represents a standard of care for pulmonary vein isolation in patients with drug-refractory paroxysmal atrial fibrillation (AF). In this setting, cryoballoon (CB) ablation has emerged as alternative therapy. However, the efficacy and safety of CB vs. RF ablation in patients with paroxysmal AF remain a matter of debate.

Methods and results

We searched electronic scientific databases for studies of CB vs. RF ablation in patients with paroxysmal AF. Aggregate data were pooled to perform a meta-analysis. The primary efficacy and safety outcomes were the recurrence of any atrial arrhythmia and procedure-related complications, respectively. A total of 6473 participants from 10 studies (CB, n = 2232 vs. RF, n = 4241) were studied. After a median follow-up of 16 months, the risk of any atrial arrhythmia recurrence (risk ratio, RR 95% confidence interval [95% CI] = 1.01 [0.90-1.14], P = 0.83) and procedure-related complications (RR [95% CI] = 0.92 [0.66-1.28], P = 0.61) were comparable between CB vs. RF ablation. Cryoballoon ablation led to a higher risk of persistent phrenic nerve palsy (RR [95% CI] = 13.60 [3.87-47.81], P < 0.01) and a lower risk of cardiac tamponade (RR [95% CI] = 0.48 [0.25-0.89], P = 0.02) compared with RF ablation. There was a trend of statistically significant interaction between the type of CB and the duration of ablation (P for interaction = 0.09).

Conclusion

In patients with paroxysmal AF, ablation therapy with CB is associated with efficacy and safety comparable to that of RF. Second-generation CB catheters seem to reduce procedure duration. Further studies are warranted to disclose the impact of second-generation CB catheters compared with RF for ablation of paroxysmal AF.

Prognostic implications and procoagulant activity of phosphatidylserine exposure of blood cells and microparticles in patients with atrial fibrillation treated with pulmonary vein isolation

The present study aimed to evaluate the procoagulant effects of phosphatidylserine (PS) exposure on blood cells and microparticles (MPs), and examine its role in predicting early recurrence atrial fibrillation (ERAF) in patients with atrial fibrillation (AF) treated with pulmonary vein isolation (PVI). Blood samples were obtained from 40 healthy controls and 56 patients with AF at baseline (prior to PVI), and 0, 1 h, 1 day, 3 days and 7 days following PVI. The exposure of PS (PS⁺) to blood cells (platelets, erythrocytes and leukocytes) and MPs was detected using flow cytometry. The procoagulant activity was evaluated by coagulation time, and the formation of factor Xa (FXa) and thrombin. In addition, independent factors associated with PS⁺ blood cells and MPs, and significant predictors of ERAF following PVI were investigated by statistical analyses. The numbers of PS⁺ blood cells and MPs were significantly increased by PVI (P<0.01). A significant decrease in coagulation time, and increases in FXa and thrombin were exhibited in the PS⁺ blood cells and MPs from patients with AF treated with PVI, whereas these alterations were inhibited by either lactadherin or anti-tissue factor (P<0.01). The maximum power of the PVI was significantly associated with platelet-derived MPs, and high-sensitivity C-reactive protein (hs-CRP) was closely associated with leukocyte-derived MPs and endothelial-derived MPs (EMPs) (P<0.01). In addition, hs-CRP and EMPs >355/µl were identified as independent predictors of ERAF (P<0.05). The increased numbers of PS⁺ platelets, erythrocytes, leukocytes and MPs contributed to the procoagulant state of AF, and hs-CRP and EMPs were able to predict ERAF following PVI.

Efficacy and safety of cryoballoon ablation versus radiofrequency catheter ablation in atrial fibrillation: an updated meta-analysis

Introduction

Cryoballoon ablation (CBA) and irrigated radiofrequency catheter ablation (RFCA) are the main treatments for drug-refractory symptomatic atrial fibrillation (AF).

Aim

To compare the efficacy and safety between CBA and RFCA for the treatment of AF.

Material and methods

We searched the Embase and Medline databases for clinical studies published up to December 2016. Studies that satisfied our predefined inclusion criteria were included.

Results

After searching through the literature in the two major databases, 20 studies with a total of 9,141 patients were included in our study. The CBA had a significantly shorter procedure time (weighted mean difference (WMD) –30.38 min; 95% CI: –46.43 to –14.33, p = 0.0002) and non-significantly shorter fluoroscopy time (WMD –3.18 min; 95% CI: –6.43 to 0.07, p = 0.06) compared with RFCA. There was no difference in freedom from AF between CBA and RFCA (CBA 78.55% vs. RFCA 83.13%, OR = 1.15, 95% CI: 0.95–1.39, p = 0.14). The CBA was associated with a high risk of procedure-related complications (CBA 9.02% vs. RFCA 6.56%, OR = 1.56, 95% CI: 1.05–2.31, p = 0.03), especially phrenic nerve paralysis (PNP, OR = 10.72, 95% CI: 5.59–20.55, p < 0.00001). The risk of pericardial effusions/cardiac tamponade was low in the CBA group (CBA 1.05% vs. RFCA 1.86%, OR = 0.62, 95% CI: 0.41–0.93, p = 0.02).

Conclusions

For AF, CBA was as effective as RFCA. However, CBA had a shorter procedure time and a non-significantly shorter fluoroscopy time, a significantly high risk of PNP and a low incidence of pericardial effusions/cardiac tamponade compared with RFCA.

Early release of high-sensitive cardiac troponin during complex catheter ablation for ventricular tachycardia and atrial fibrillation

BACKGROUND

Radiofrequency ablation results in intentional cardiac injury. We aimed to assess the kinetics of cardiac injury as measured by cardiac troponin release following ventricular ablation and atrial ablation.

METHODS

Patients undergoing ablation for ventricular tachycardia (VT) with structural heart disease (19 patients) or atrial fibrillation (AF, 24 patients) were prospectively enrolled. High-sensitivity cardiac troponin T (hs-cTnT) and high-sensitivity cardiac troponin I (hs-cTnI) were measured before ablation as well as 30 min, 60 min, 90 min, 120 min, 4 h, 8 h, and 24 h after applying the first ablation lesion.

RESULTS

Median ablation time, power used, and energy delivered were 28 min, 39 W, and 69,713 J in VT ablations and 55 min, 29 W, and 95,425 J in AF ablations, respectively. Release of hs-cTnT occurred promptly with both, but reached greater levels earlier for ventricular compared to atrial ablation (hs-cTnT after 30 min 191 vs. 31 ng/l, after 1 h 467 vs. 80 ng/l; hs-cTnI after 30 min 132 vs. 30 ng/l, after 1 h 331 vs. 76 ng/l; p < 0.001 for all comparisons). After 24 h, levels were similar (hs-cTnT 1325 vs. 1303 ng/l, p = 0.92; hs-cTnI 2165 vs. 1996 ng/l, p = 0.55). Levels of hs-cTnT after 24 h correlated well with the energy delivered in AF ablations (r = 0.81 and r = 0.75, p < 0.001), but not in VT ablations (r = 0.35 and r = 0.44, p = ns).

CONCLUSIONS

Evidence of cardiac injury as indicated by the release of hs-cTnT and hs-cTnI occurs early with atrial and ventricular ablation. Higher early levels are observed in ventricular ablations, but levels are similar after 24 h. The extent of total troponin release seems to correlate well with the amount of energy delivered in AF ablations, but not in VT ablations.