Sex differences in the predictors of recurrent atrial fibrillation after catheter ablation: insights from the Kansai Plus Atrial Fibrillation (KPAF) registry

Background

The impact of sex differences on the clinical outcomes of radiofrequency catheter ablation (RFCA) of atrial fibrillation (AF) is controversial. We previously reported that females experienced more frequent AF recurrences than males after the index and last RFCA procedures.

Purpose

To identify the risk factors associated with recurrent AF in females and males after RFCA of AF.

Methods

We conducted a large-scale, prospective, multicenter, observational study (Kansai Plus Atrial Fibrillation Registry). We enrolled 5010 consecutive patients who underwent an initial RFCA of AF at 26 centers (64±10 years; 1369 [27.3%] females; non-paroxysmal AF, 35.7%). The median follow-up duration was 2.9 years.

Results

The incidence of AF recurrences after a single procedure was 43.3% in females and 39.0% in males. After a multivariate adjustment at baseline, the significant predictors of AF recurrence in females after the index RFCA were non-paroxysmal AF (hazard ration [HR],1.59; 95% confidence interval [CI],1.31–1.93, p<0.0001), a history of AF ≥2 years (HR,1.47; 95% CI,1.24–1.74, p<0.0001), coronary artery disease (HR,1.43; 95% CI,1.03–1.98, p=0.0035), and an estimated glomerular filtration rate (eGFR)<60 mL/min/1.73m2 (HR,1.46; 95% CI,1.10–1.95, p=0.0086). On the other hand, significant predictors of AF recurrence in males after the index RFCA were non-paroxysmal AF (HR,1.54; 95% CI,1.37–1.73, p<0.0001), a history of AF ≥2 years (HR,1.40; 95% CI,1.26–1.56, p<0.0001), the number of antiarrhythmic drugs (HR,1.06; 95% CI,1.003–1.13, p=0.040), a left atrial diameter≥40mm (HR,1.13; 95% CI,1.007–1.27, p=0.038), and dilated cardiomyopathy (HR,1.55; 95% CI,1.07–2.26, p=0.021), however, an eGFR<60 mL/min/1.73m2 was not associated with AF recurrence in males (HR, 1.00; 95% CI, 0.88–1.13, p=0.97).

Conclusion

The Kansai Plus Atrial Fibrillation Registry revealed a distinct sex difference in terms of the predictors of recurrent AF after RFCA. Non-Paroxysmal AF and a long history of AF were common risk factors both in females and males. However, renal dysfunction was a significant predictor of AF recurrence in females, while it was not a risk of recurrence in males.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Research Institute for Production Development in Kyoto, Japan.

The impact of catheter ablation for patients with asymptomatic atrial fibrillation: subanalysis of kansai plus atrial fibrillation (kpaf) registry

Background

Catheter ablation (CA) of atrial fibrillation (AF) for symptomatic patients improves the quality of life and prognosis of patients with heart failure. However, the impact of CA for asymptomatic patients is still controversial.

Purpose

We aimed to investigate the clinical outcomes of CA of AF for asymptomatic patients compared to those for symptomatic patients.

Methods

A total of 5,013 patients from the Kansai Plus Atrial Fibrillation (KPAF) Registry who underwent CA were screened. The patients were divided into three groups by type of AF; paroxysmal (PAF), persistent (PEAF) and long standing (LSAF) and the patients in each type of AF were divided into two groups: asymptomatic and symptomatic. The primary endpoint was recurrent supraventricular tachyarrhythmias lasting for more than 30 seconds during follow-up 4 years after CA. The secondary endpoint was a composite of cardiovascular, cerebral, and gastrointestinal events during follow-up 4 years after CA. The incidence of complications related to CA between asymptomatic and symptomatic patients was also evaluated. Kaplan–Meier analysis was employed to estimate the primary and secondary endpoints. The statistical differences in primary and secondary endpoints between asymptomatic and symptomatic patients were evaluated using a log–rank test. The impact of symptom due to AF on the primary and secondary endpoint was evaluated using a Cox hazard analysis. The difference in incidence of complications between asymptomatic and symptomatic patients was evaluated using a chi–square test.

Results

In this study population, PAF was the most frequent at 64.4%, followed by PEAF (22.7%) and LSAF (13.0%). There were some significant differences in the baseline characteristics between asymptomatic and symptomatic patients in each type of AF. The proportion of male was significantly higher in asymptomatic patients than symptomatic patients in PAF (81.2% versus 67.2%, p<0.001) and PEAF (86.4% versus 74.3%, p<0.001). Left atrial diameter was larger in asymptomatic patients than symptomatic patients only in PAF (40±6mm versus 38±6mm, p<0.001). In all types of AF, there was no significant difference in primary endpoint between asymptomatic and symptomatic patients as follows: 37.5% versus 40.6% (p=0.6) in PAF, 45.2% versus 55.1% (p=0.09) in PEAF and 59.3% versus 63.6% (p=1.0) in LSAF. There was also no significant difference in secondary endpoint between asymptomatic and symptomatic patients: 7.1% versus 6.8% (p=0.7) in PAF, 5.4% versus 8.7% (p=0.3) in PEAF and 4.4% versus 5.1% (p=0.5) in LSAF. In a Cox hazard analysis, the symptom did not affect both of the primary and secondary endpoints in each type of AF. In regard to the incidence of complications related to CA, there was no significant difference between asymptomatic and symptomatic patients in each type of AF.

Conclusion

CA of AF for asymptomatic patients can be safe and can lead to equivalent outcomes as well as symptomatic patients.

Funding Acknowledgement

Type of funding source: None

Risk factors for major bleeding during prolonged anticoagulation therapy in cancer-associated venous thromboembolisms: from the COMMAND VTE registry

Background/Introduction

Patients with cancer-associated venous thromboembolisms (VTEs) are at a high risk for recurrent VTEs and are recommended to receive prolonged anticoagulation therapy if they are at a low risk for bleeding. However, there are no established risk factors for bleeding during prolonged anticoagulation therapy.

Purpose

We aimed to identify the risk factors for major bleeding during prolonged anticoagulation therapy in cancer-associated VTE patients.

Methods

The COMMAND VTE Registry is a multicenter retrospective registry enrolling 3027 consecutive patients with acute symptomatic VTEs among 29 Japanese centers between January 2010 and August 2014. After excluding those without active cancer (N=2332), patients with major bleeding (N=15), death (N=17), and lost to follow-up (N=10) within 10 days after the diagnosis, and those without anticoagulation therapy beyond 10 days after the diagnosis (N=61), the present study population consisted of 592 cancer-associated VTE patients with anticoagulation therapy beyond 10 days after the diagnosis. The outcome measurement was International Society of Thrombosis and Hemostasis (ISTH) major bleeding during anticoagulation therapy beyond 10 days, which occurred before the first discontinuation of the anticoagulation therapy. We constructed a multivariable Cox proportional hazard model to estimate the hazard ratio (HR) and 95% confidence intervals (CIs) of the potential risk factors for major bleeding. As a sensitivity analysis, we used Fine and Gray's method to estimate the HR and 95% CI, taking into account the competing risk of all-cause death.

Results

During a median follow-up period of 199 days, major bleeding occurred in 72 patients (31 patients within 3 months; 41 beyond 3 months). The cumulative incidence of major bleeding was 5.8% at 3-months, 13.8% at 1-year, 17.5% at 2-year, and 28.1% at 5-years. The most frequent major bleeding site was gastrointestinal (47%), followed by intracranial (17%) and genitourinary (11%). Major bleeding tended to occur from the sites of the cancer, however, the sites of the cancer and sites of major bleeding were not necessarily concordant. The multivariable Cox regression model demonstrated that terminal cancer (adjusted HR, 4.17; 95% CI, 2.22–7.85, P<0.001), chronic kidney disease (adjusted HR, 1.89; 95% CI 1.06–3.37, P=0.031), and gastrointestinal cancer (adjusted HR, 1.78; 95% CI, 1.04–3.04, P=0.037) were independently associated with an increased risk of major bleeding. After taking into account the competing risk of all-cause death, the multivariable Cox regression model demonstrated almost consistent results with the main analysis.

Conclusions

Major bleeding events were common during prolonged anticoagulation therapy in real-world cancer-associated VTE patients. Terminal cancer, chronic kidney disease, and gastrointestinal cancer were the independent risk factors for major bleeding.

Funding Acknowledgement

Type of funding source: Foundation. Main funding source(s): Research Institute for Production Development, Mitsubishi Tanabe Pharma Corporation

Visualization of ferroaxial domains in an order-disorder type ferroaxial crystal

Ferroaxial materials that exhibit spontaneous ordering of a rotational structural distortion with an axial vector symmetry have gained growing interest, motivated by recent extensive studies on ferroic materials. As in conventional ferroics (e.g., ferroelectrics and ferromagnetics), domain states will be present in the ferroaxial materials. However, the observation of ferroaxial domains is non-trivial due to the nature of the order parameter, which is invariant under both time-reversal and space-inversion operations. Here we propose that NiTiO₃ is an order-disorder type ferroaxial material, and spatially resolve its ferroaxial domains by using linear electrogyration effect: optical rotation in proportion to an applied electric field. To detect small signals of electrogyration (order of 10⁻⁵ deg V⁻¹), we adopt a recently developed difference image-sensing technique. Furthermore, the ferroaxial domains are confirmed on nano-scale spatial resolution with a combined use of scanning transmission electron microscopy and convergent-beam electron diffraction. Our success of the domain visualization will promote the study of ferroaxial materials as a new ferroic state of matter.

The presence of ferroaxial domain states is recently experimentally demonstrated by a nonlinear optical technique, which lacks high spatial resolution to visualize ferroaxial domains. Here, the authors visualize spatial distributions of ferroaxial domains in NiTiO₃ showing an order-disorder type ferroaxial transition.

In-vitro fertilisation-embryo-transfer complicates the antenatal diagnosis of placenta accreta spectrum using MRI: a retrospective analysis

AIM

To evaluate the diagnostic accuracy of magnetic resonance imaging (MRI) for the antenatal diagnosis of placenta accreta spectrum (PAS).

MATERIALS AND METHODS

Data from 95 patients with placenta previa or low-lying placenta who underwent MRI at Osaka University Hospital for the antenatal diagnosis of PAS between January 2013 and December 2018 were reviewed retrospectively. The antenatal MRI signs suggesting PAS were assessed. Patients were divided into two groups depending on whether they were diagnosed with PAS. Factors that affected PAS diagnosis were identified using multivariate analysis.

RESULTS

The diagnostic accuracy of MRI for detecting PAS was as follows: 71.4% sensitivity, 96.4% specificity, and area under the curve (AUC) of 0.839 (95% confidence interval [CI]: 0.73-0.91). The diagnostic accuracy was lower in patients with in-vitro fertilisation with embryo transfer (IVF-ET): 22.2% sensitivity, 93.3% specificity, and AUC=0.578 (95% CI: 0.417-0.724). On multivariate analysis, only IVF-ET showed a significant association with false-positive or -negative MRI diagnosis of PAS (adjusted odds ratio: 26.5; 95% CI: 2.42-289.4; p=0.007).

CONCLUSION

IVF-ET affects the antenatal diagnosis of PAS using MRI.

In operando visualization of electrolyte stratification dynamics in lead-acid battery using phase-contrast X-ray imaging

An understanding of electrolyte stratification behaviours in lead-acid battery electrolytes during battery operation is important for optimal operation and design of lead-acid batteries for vehicle applications. In this paper, we present an in operando phase-contrast X-ray imaging technique for quantitatively visualizing electrolyte stratification dynamics that arise in electrolytes during battery operation.

Genome-wide DNA methylation analysis identifies promoter hypermethylation in canine malignant melanoma

Canine malignant melanoma is a common cancer with a high mortality rate. Although previous studies have evaluated various aspects of this tumour, the exact mechanism of tumourigenesis remains unknown. Epigenetic mechanisms, such as DNA methylation, have recently gained attention as aetiological factors for neoplasia in humans. This study aimed to analyse genome-wide DNA methylation patterns in canine malignant melanoma based on next-generation sequencing data. A total of 76,213 CpG sites, including 29,482 sites in CpG islands (CGIs), were analysed using next-generation sequencing of methylation-specific signatures, obtained by sequential digestion with enzymes, to compare normal oral mucosal samples from four healthy dogs, four canine melanoma cell lines (3 oral cavity and 1 skin), and five clinical samples of oral canine melanoma. Malignant melanoma showed increased methylation at thousands of normally unmethylated CpG sites in CGIs and decreased methylation at normally methylated CpG sites in non-CGIs. Interestingly, the promoter regions of 81-393 genes were hypermethylated; 23 of these genes were present in all melanoma cell lines and melanoma clinical samples. Among these 23 genes, six genes with "sequence-specific DNA binding" annotation were significantly enriched, including three Homeobox genes-HMX2, TLX2, and HOXA9-that may be involved in the tumourigenesis of canine malignant melanoma. This study revealed widespread alterations in DNA methylation and a large number of hypermethylated genes in canine malignant melanoma.

Pathogenic Autoimmunity in Atherosclerosis Evolves From Initially Protective Apolipoprotein B100-Reactive CD4+ T-Regulatory Cells

BACKGROUND

Throughout the inflammatory response that accompanies atherosclerosis, autoreactive CD4⁺ T-helper cells accumulate in the atherosclerotic plaque. Apolipoprotein B₁₀₀ (apoB), the core protein of low-density lipoprotein, is an autoantigen that drives the generation of pathogenic T-helper type 1 (T_H1) cells with proinflammatory cytokine secretion. Clinical data suggest the existence of apoB-specific CD4⁺ T cells with an atheroprotective, regulatory T cell (T_reg) phenotype in healthy individuals. Yet, the function of apoB-reactive T_regs and their relationship with pathogenic T_H1 cells remain unknown.

METHODS

To interrogate the function of autoreactive CD4⁺ T cells in atherosclerosis, we used a novel tetramer of major histocompatibility complex II to track T cells reactive to the mouse self-peptide apo B_978-993 (apoB⁺) at the single-cell level.

RESULTS

We found that apoB⁺ T cells build an oligoclonal population in lymph nodes of healthy mice that exhibit a T_reg-like transcriptome, although only 21% of all apoB⁺ T cells expressed the T_reg transcription factor FoxP3 (Forkhead Box P3) protein as detected by flow cytometry. In single-cell RNA sequencing, apoB⁺ T cells formed several clusters with mixed T_H signatures that suggested overlapping multilineage phenotypes with pro- and anti-inflammatory transcripts of T_H1, T helper cell type 2 (T_H2), and T helper cell type 17 (T_H17), and of follicular-helper T cells. ApoB⁺ T cells were increased in mice and humans with atherosclerosis and progressively converted into pathogenic T_H1/T_H17-like cells with proinflammatory properties and only a residual T_reg transcriptome. Plaque T cells that expanded during progression of atherosclerosis consistently showed a mixed T_H1/T_H17 phenotype in single-cell RNA sequencing. In addition, we observed a loss of FoxP3 in a fraction of apoB⁺ T_regs in lineage tracing of hyperlipidemic Apoe^-/- mice. In adoptive transfer experiments, converting apoB⁺ T_regs failed to protect from atherosclerosis.

CONCLUSIONS

Our results demonstrate an unexpected mixed phenotype of apoB-reactive autoimmune T cells in atherosclerosis and suggest an initially protective autoimmune response against apoB with a progressive derangement in clinical disease. These findings identify apoB autoreactive T_regs as a novel cellular target in atherosclerosis.

Antiferromagnetic fluctuations and charge carrier localization in ferromagnetic bilayer manganites: electrical resistivity scales exponentially with short-range order controlled by temperature and magnetic field

The compound La2-2xSr1+2xMn2O7,x= 0.30-0.40, consists of bilayers of ferromagnetic metallic MnO2sheets that are separated by insulating layers. The materials show colossal magnetoresistance-a reduction in resistivity of up to two orders of magnitude in a field of 7 T-at their three-dimensional ordering temperatures,TC= 90-126 K, and are the layered analogues of the widely studied pseudo-cubic perovskite manganites, R1-xAxMnO3(R = rare earth, A = Ca, Sr, Ba, Pb). Two distinct short-range orderings-antiferromagnetic fluctuations and correlated polarons, which are related to the magnetic and the lattice degrees of freedom respectively-have previously been discovered in La2-2xSr1+2xMn2O7,x= 0.40, and have each been qualitatively connected to the resistivity. Here, in a comprehensive study as a function of both temperature and magnetic field for the different hole-concentrations per Mn site ofx= 0.30 and 0.35, we show that antiferromagnetic fluctuations also appear at temperatures just aboveTC, and that the intensities of both the antiferromagnetic fluctuations and polaron correlations closely track the resistivity. In particular, forx= 0.35 we show that there is a simple scaling relation between the intensities of the antiferromagnetic fluctuations and the in-plane resistivity that applies for the temperatures and magnetic fields used in the experiments. The results show that antiferromagnetic fluctuations are a common feature ofLa2-2xSr1+2xMn2O7with ferromagnetic bilayers, and that there is a close connection between the antiferromagnetic fluctuations and polarons in these materials.

Efficacy of guselkumab in a subpopulation with pustulotic arthro-osteitis through week 52: an exploratory analysis of a phase 3, randomized, double-blind, placebo-controlled study in Japanese patients with palmoplantar pustulosis

Background

Previous studies of guselkumab have demonstrated clinical benefits in patients with plaque‐type psoriasis, generalized pustular psoriasis, erythrodermic psoriasis and palmoplantar pustulosis (PPP).

Objective

The aim of this exploratory analysis of a double‐blind, multicenter, placebo‐controlled, phase 3 study in Japanese patients with PPP was to evaluate the efficacy of guselkumab in the subset of patients with pustulotic arthro‐osteitis (PAO).

Methods

Patients were randomized to receive guselkumab 100 or 200 mg at weeks 0, 4, 12 and every 8 weeks, or placebo with cross‐over to guselkumab 100 or 200 mg at week 16 (placebo group). Efficacy endpoints were changes from baseline in magnetic resonance imaging (MRI) score, EuroQOL‐5 dimensions (EQ‐5D) index score, EQ‐5D pain/discomfort dimension score and C‐reactive protein (CRP, mg/L) level in all PAO patients through week 52. Data from both guselkumab groups were combined and presented as results for a single overall guselkumab group.

Results

Among 159 patients with PPP, 66 with PAO were randomized across treatment groups. For patients with MRI data for all regions assessed, the proportion of patients in the guselkumab group with PAO characterized as severe decreased from 23.8% (10/42) at baseline to 5.4% (2/42) at week 52. The mean (SD) change from baseline at week 52 in EQ‐5D index score was 0.20 (0.17) among PPP patients with PAO and 0.15 (0.17) among those without PAO in the guselkumab group. Among all PAO patients, the proportions with an EQ‐5D pain/discomfort dimension score of no or slight pain/discomfort in the guselkumab group increased from baseline to week 52 [33.3% (7/21) vs. 87.5% (35/40)]. The mean (SD) CRP levels decreased in all PAO patients in the guselkumab group at week 52 compared to baseline [−1.71 (8.16) mg/L].

Conclusion

Guselkumab treatment showed beneficial outcomes for PAO signs and symptoms in Japanese patients with PPP.

Dependence of the V/III Ratio on Indium Incorporation in InGaN Films Grown by Metalorganic Vapour Phase Epitaxy

InGaN epitaxial layers were grown on c-plane sapphire substrates using the metalorganic vapour phase epitaxy (MOVPE) system at 760 °C. By varying the total flow rate of group-III sources (TMI+TEG) with a fixed molar ratio of group-III sources [TMI/(TMI+TEG)], the influence of V/III ratio were investigated from 4500 to 20000. The grown N-polar InGaN layers were investigated by atomic force microscopy and it is found that the surface roughness decreases with increasing the V/III ratios. High resolution X-ray diffraction analyses show that the phase separation decreases with increasing the V/III ratios. Photoluminescence measurements reveal that the peak position of the band-edge emission shifted toward the shorter wavelength with increasing the V/III ratios. Reciprocal space mapping (RSM) analyses were carried out on InGaN films. At low V/III ratio, the phase separation can be detected in InGaN films.

Excess length of hospital stay, mortality and cost attributable to Clostridioides (Clostridium) difficile infection and recurrence: a nationwide analysis in Japan

Clostridioides (Clostridium) difficile infection (CDI) is the leading cause of infectious diarrhoea in hospitalised patients, representing a substantial economic burden driven mainly by increased length of hospital stay (LoS). Currently in Japan, limited evidence on CDI-associated excess LoS is available. We conducted a retrospective, matched-cohort study using a large, Japanese, hospital-based administrative database. CDI was defined as CDI treatment plus either CDI diagnosis or positive enzyme immunoassay result. Propensity score matching at the time of CDI or recurrent CDI (rCDI) onset was applied to adjust baseline confounding and immortal time bias. The analysis included 5 994 054 hospitalisation records during 2008-2017, of which 11 823 were identified as CDI and 1359 as rCDI. The median excess LoS attributable to CDI and rCDI was 3 days and 6.5 days, respectively. The excess mortality attributable to CDI was 6.9%; there was no excess mortality attributable to rCDI (-1.9%). The median difference in costs attributable to CDI and rCDI during the residual stay was JPY 130 296 (USD 1185) and JPY 81 054 (USD 737) per hospitalisation, respectively. By adjusting the biases, the burden of CDI in Japan was evaluated. The findings could support decision making and resource allocation for CDI management in Japanese hospitals.

P762 Preserved mitral apparatus dynamics predict the improvement of acute ischemic mitral regurgitation: four-dimensional quantitative echocardiographic study

Background

We sought to evaluate the predictive value of acute stage mitral apparatus geometry and dynamics for the reduction of ischemic mitral regurgitation (IMR) in the remote phase after successful primary percutaneous coronary intervention (pPCI) by using real-time 3D-transthoracic echocardiography (3D-TTE).

Methods

We performed 2D and 3D-TTE in consecutive 44 first acute MI patients with more than mild IMR within 3 days after successful pPCI. 3DTTE of left ventricle (LV) volumes and mitral apparatus dynamics through the cardiac cycle were quantified offline. We compared the 3D geometric and dynamic parameters in the acute phase between 1)20 remained MR group and 2)24 improved MR group in 6-to-12 months after MI onset.

Results

Ejection fraction (EF) was preserved in the improved MR group compared to the remained MR group (49.0 ± 11.2 vs. 56.5 ± 7.0%, p = 0.013). Mitral valve annulus area, leaflet tenting length and papillary muscles spatial position had no significant difference between the two groups (all p > 0.05) throughout cardiac cycle. In contrast, mitral annulus saddle shape was preserved in the improved MR group than the remained MR group (p = 0.010) and annular area changed dynamically through early- to late-systole in the improved MR group (phasic p = 0.017) despite it was adynamic in remained MR group (phasic p = 0.201). Conclusions: IMR improvement in the remote phase after AMI associated with preserved EF, mitral annulus saddle shape and dynamics during systole in the acute phase of MI. 4D dynamics of the mitral apparatus can be clinically useful predictor of the improvement in acute IMR and may contribute to the clinical decision making including surgical or percutaneous intervention for IMR.

P292 The risk of adverse outcome with ischemic mitral regurgitation at 6-month after myocardial infarction: possible benefit of early intervention by transcatheter mitral-valve repair

Background

The latest study has demonstrated the better outcomes of transcatheter mitral-valve repair in patients with decompensated heart failure (HF) and left ventricular (LV) dysfunction. However, it is unknown whether earlier intervention for mitral regurgitation (MR) can improve the outcome of myocardial infarction (MI).

Purpose

The aim of this study was to investigate the prognostic value of ischemic MR (IMR) at 6-month after MI for the later incidence of HF and death.

Methods

We retrospectively examined 723 MI patients who were admitted to our hospital. 95.5% of the patients were treated by primary coronary intervention. Patients were clinically followed-up at 6-month after the onset of MI, and divided into 3 groups according to the degree of IMR, i.e. No/Trivial IMR group (n = 528), Mild IMR group (n= 154) and ≥Moderate IMR group (n= 41). We compared the later incidence of hospitalization for HF and all-cause death at 3-year for each group.

Results

The studied population had preserved ejection fraction (EF) (56.9 ± 10.7%, average) and mostly asymptomatic at 6-month after MI. All-cause mortality within 3-year was higher in patients with ≥Moderate IMR (p < 0.001), and the incidence of hospitalization for HF was significantly higher depends on the degree of IMR at 6-month (p < 0.001). Multivariate analysis showed EF and the degree of IMR were the independent predictor for the hospitalization for HF.

Conclusions

IMR at 6-month after MI was associated with the later adverse events despite relatively preserved LV contraction without heart failure symptoms at the index examination. Early intervention for IMR potentially benefit for the better outcome.

Abstract P292 Figure. Caplan-Meier estimates on adverse events

P34 The effect of sex on the efficacy and safety of dabigatran dual therapy in atrial fibrillation after PCI: a subgroup analysis from the RE-DUAL PCI trial

Funding Acknowledgements

Boehringer Ingelheim International GmbH

On Behalf

The Re-DUAL PCI Investigators

Background

The RE-DUAL PCI study (NCT02164864) compared dabigatran dual antithrombotic therapy (D-DAT) with warfarin triple antithrombotic therapy (W-TAT) in patients with atrial fibrillation (AF) undergoing percutaneous coronary intervention (PCI). As previously reported D-DAT reduced bleeding compared with W-TAT and was non-inferior with regard to thromboembolic events. 

Aim 

The aim of this subgroup analysis of RE-DUAL was to assess the relationship between sex and treatment effects of D-DAT and W-TAT on bleeding and thromboembolic outcomes.

Methods

Patients were randomized to receive W-TAT (warfarin, clopidogrel or ticagrelor, and aspirin) or D-DAT (dabigatran 110 or 150 mg twice daily with clopidogrel or ticagrelor; D110- or D150-DAT). Younger patients (aged < 80 yrs. [< 70 yrs. in Japan]) and US patients irrespective of age received D110-DAT, D150-DAT or W-TAT; older patients (aged ≥ 80 yrs. in non-US countries [≥ 70 yrs. in Japan]) received only D110-DAT or W-TAT. Bleeding and thromboembolic outcomes were assessed according to treatment group and by sex (female vs. male).

Results

A total of 2725 patients were randomized; 2070 patients were male (76.0%) and 655 (24.0%) were female. Overall females were older at time of PCI than males (73.2 ± 7.9 vs. 70.0 ± 8.8 years). The mean CHA2DS2-VASc and modified HAS-BLED scores were higher in women at 4.5 and 2.8, respectively, than in men at 3.3 and 2.7, respectively. 

For the primary endpoint of major bleeding events or clinically relevant non-major bleeding events, treatment effects of D110-DAT vs. W-TAT were consistent for female and male patients (females: HR 0.69, 95% CI 0.47-1.01, males HR 0.46, 95%CI 0.37-0.59, interaction p-value 0.084). Similarly, consistent treatment effects were seen for the primary endpoint with D150-DAT vs W-TAT in female and male patients (females HR 0.74, 95% CI 0.48-1.16, males HR 0.71, 95% CI 0.56-0.90, interaction p value 0.83). 

No interaction between sex and treatment was observed for D110- or D150-DAT vs W-TAT with regard to the composite efficacy endpoint of death, thromboembolic events or unplanned revascularization (interaction p values 0.73 and 0.72, respectively) (figure).

Conclusion

The treatment effect of dabigatran 110 mg and 150 mg dual therapy vs warfarin triple therapy was consistent across sex groups. This suggests that female and male patients with AF undergoing PCI should be treated equally in terms of the dosage of dabigatran selected for dual therapy strategies.

Abstract P34 Figure. Re-DUAL sex subgroup analysis

1182 Clinical evidence of the mitral valve leaflet remodeling after st-elevation acute myocardial infarction: longitudinal observation using real-time 3D echocardiography

Background

Mitral valve (MV) leaflet remodeling after acute myocardial infarction (AMI) has been proposed as biological and physiological reaction under the ischemic environment mainly by animal experiments. Clinical evidence of leaflet growth after AMI is lacking.

Purpose

We aimed to assess the clinical evidence of the mitral valve leaflet remodeling after acute myocardial infarction by serial 2D/3D transthoracic echocardiography.

Methods

Sixty-six patients with first-onset ST-elevation MI (33 anterior and 33 inferior) were serially examined by 2D/3D-transthoracic echocardiography. MV complex geometry including leaflet surface area and leaflet thickness was quantitatively analyzed in acute phase and 6-month follow-up.

Results

3D-leaflet surface area was significantly increased in 6-month follow-up (anterior MI; 5.58 [4.93-6.00] versus 5.98 [5.68-6.40] cm²/m²; P < 0.001, inferior MI; 5.48 [4.69-6.07] versus 5.79 [4.74-6.37] cm²/m²; P < 0.001). In anterior MI, both anterior and posterior leaflet lengths significantly increased (anterior leaflet; 12.78 [11.55-13.55] versus 13.63 [12.52-14.15] mm/m²; P = 0.001, posterior leaflet; 9.61 [8.73-10.77] versus 9.84 [8.94-10.96] mm/m²; P = 0.037). In inferior MI, posterior leaflet length significantly increased (9.18 [8.50-10.38] versus 10.00 [8.56-10.85] mm/m²; P = 0.029), while there was no significant change in anterior leaflet length (12.54 [11.61-13.56] versus 12.56 [12.08-14.06] mm/m²; P = 0.214). Leaflet thickness was found to become greater in both groups in 6-month follow-up (anterior MI; 1.08 [0.92-1.21] versus 1.32 [1.25-1.45] mm; P < 0.001, inferior MI; 1.14 [0.98-1.25] versus 1.32 [1.21-1.49] mm; P < 0.001) (Figure).

Conclusions

In six months from the onset of AMI, MV enlarged in area and increased in thickness. Anterior leaflet mainly enlarged in anterior MI, while posterior leaflet enlarged in inferior MI. This is the first clinical evidence of the MV remodeling after AMI, and long-year follow-up should contribute to assess the course of valve growth with relation to ischemic mitral regurgitation.

Abstract 1182 Figure. 3D analysis of the mitral valve

P737Endothelial ERK2/thromboxane receptor pathway induces endothelial dysfunction, insulin resistance and steatohepatosis through superoxide with high fat high sucrose diet

Introduction

Metabolic syndrome (MetS) is well known as the risk of cardiovascular diseases associated with endothelial dysfunction and induces steatohepatosis. Insulin resistance is a major character of MetS, which affects intracellular signaling pathways and endothelial function. Extracellular signal-regulated kinase (ERK) is a major component of insulin signal and many of vasoactive peptides, which were released in MetS, can activate it in endothelium. However, the role of endothelial ERK in nitric oxide (NO) bioactivity in MetS in in vivo has been unknown.

Purpose

The aim of this study is to clarify the role of endothelial ERK2 on NO bioactivity in mice model of MetS.

Methods and results

We created endothelial specific ERK2 knock out mice (EE2KO) crossing Tie2-Cre mice and ERK2 flox mice and fed them with normal or high-fat/high-sucrose diet (HFHSD) for 24 weeks. Serum glucose and insulin levels and HOMA-IR were lowered in EE2KO with HFHSD without changing body weight. In wild type mice (WT) with HFHSD, nonalcoholic fatty liver disease (NAFLD) activity score, fibrosis score and serum ALT level were increased, all of which were blunted in EE2KO. EE2KO with HFHSD lowered systolic blood pressure (WT: 123.7±5.83 mmHg, EE2KO: 101.4±3.66 mmHg, P<0.01, N=8) without changing heart rate, which was increased to the same levels with L-NAME, an endothelial NO synthase inhibitor, in both groups. Serum NO levels measured with serum nitrite/nitrate concentrations were increased in EE2KO with HFHSD (WT: 23.10±3.74 μmol/l, EE2KO: 41.71±6.73 μmol/l, P<0.05, N=12). Endothelial function was assessed with the isometric tension measurement of aortic rings with acetylcholine (ACh). ACh-induced relaxation was improved in EE2KO with HFHSD. Superoxide production of aorta from EE2KO was lowered than WT with HFHSD in dihydroethidium (DHE) staining. S18886, an antagonist of the thromboxane A2-prostanoid (TP) receptor, decreased superoxide production of aorta in DHE staining resulting in improving endothelial function in the isometric tension measurement of aortic rings. Oral administrations of S18886 decreased systolic blood pressure, serum fasting glucose and insulin levels, and surprisingly improved steatohepatosis by decreasing NAFLD activity score and fibrosis score.

Relaxation of aortic rings with ACh

Conclusions

Endothelial ERK2/TP receptor pathway increases superoxide production and decreased NO bioactivity, resulting in deteriorating endothelial function, insulin resistance and steatohepatosis, which were improved by antagonist of the TP receptor in mice model of MetS. The present study indicates that ERK2/TP pathway could be a therapeutic target for complications of MetS.

P832LDL-C levels on statins and cardiovascular event risk in stable coronary artery disease: An observation from the REAL-CAD study

Background

The relation between very low on-treatment low-density lipoprotein cholesterol (LDL-C) level and the cardiovascular event risk is still unclear in patients receiving the same doses of statins.

Methods

From the REAL-CAD study comparing high-dose with low-dose pitavastatin therapy in Japanese patients with stable coronary artery disease, 11105 patients without reported non-adherence for the study drug were divided into 3 groups according to the on-treatment LDL-C level at 6-month (<70 mg/dL, 70–100 mg/dL, and ≥100 mg/dL; N=1016, N=3078, and N=1665 in the pitavastatin 1 mg/day stratum; N=2431, N=2524, and N=391 in the pitavastatin 4 mg/day stratum). Primary outcome measure was a composite of cardiovascular death, non-fatal myocardial infarction, non-fatal ischemic stroke, or unstable angina requiring emergent admission.

Results

In the pitavastatin 1 mg/day stratum, cumulative 4-year incidence of the primary outcome measure was not significantly different across the 3 groups (5.0%, 5.7%, and 5.2%, P=0.51), while in the 4 mg/day stratum, it was significantly higher in the LDL-C ≥100 mg/dL group than in other groups (4.5%, 3.4%, and 9.1%, P<0.001). The adjusted risks of the LDL-C <70 mg/dL group relative to the LDL-C 70–100 mg/dL group (reference) remained insignificant for the primary outcome measure in both 1 mg/day and 4 mg/day strata (HR 0.84, 95% CI 0.58–1.18, P=0.32, and HR 1.25, 95% CI 0.88–1.79, P=0.22). The adjusted risk of LDL-C ≥100 mg/dL group relative to the reference group was not significant for the primary outcome measure in the 1 mg/day stratum (HR 0.82, 95% CI 0.60–1.11, P=0.21), while it was highly significant in the 4 mg/day stratum (HR 3.32, 95% CI 2.08–5.17, P<0.001). In the on-treatment LDL-C ≥100 mg/dL group in the 4 mg/day stratum, LDL-C increased by 6.3 mg/dL from baseline to 6-month despite dose escalation of pitavastatin from 1 mg/day to 4 mg/day, suggesting the presence of unreported poor adherence in this small subgroup.

Adjusted Effects of On-treatment LDL-C

Conclusions

Very low on-treatment LDL-C level (<70 mg/dL) was not associated with lower cardiovascular event risk compared with moderately low on-treatment LDL-C level (70–100 mg/dL) in patients receiving the same doses of statins. Too much emphasis on the target LDL-C strategy might mislead the clinical practice.

Acknowledgement/Funding

The Comprehensive Support Project for Clinical Research of Lifestyle-Related Disease of the Public Health Research Foundation.

P2238Prognostic value and incremental benefit of ischaemic myocardial burden subtended by non-invasive CT-derived fractional flow reserve (FFRCT) significant stenoses

Background

Fractional flow reserve derived from CT-coronary angiography (FFRCT) accurately identifies ischaemic vessels which may be associated with clinical outcomes. Its predictive value in grey zone FFRCT values between 0.7–0.8 is not defined. The technique permits estimation of burden of ischaemic myocardium subtended by FFRCT significant vessels.

Purpose

To evaluate the prognostic value and incremental benefit of FFRCT defined ischaemic myocardial burden when compared to FFRCT alone.

Methods

This is a subanalysis of NXT (Analysis of Coronary Blood-Flow Using CTA:Next-Steps), a prospective study of stable coronary artery disease (CAD) patients referred for invasive angiography (ICA) undergoing invasive FFR, CTA and FFRCT in whom treating physicians had been blinded to FFRCT results. Primary endpoint, defined as a composite of non-fatal myocardial infarction and any revascularisation, was determined in 206 patients (age 64±9.5 years, 64% male) and 618 vessels. Burden of ischaemic myocardium was defined as percentage of myocardium subtended beyond the point at which a vessel's FFRCT becomes ≤0.8 as estimated by APPROACH score (FFRCT-APPROACH). In significant FFRCT vessels, the predictive value and incremental benefit of FFRCT-APPROACH was compared with significant FFRCT (≤0.8) for primary endpoint as measured by area under the receiver operator characteristic curve (AUC). Significant ischaemic myocardial burden was defined as >10%. The incidence and relationship between the primary endpoint with each 10% increase in FFRCT-APPROACH and 0.05-unit decrease in FFRCT values ≤0.8 was determined.

Results

Significant FFRCT was identified in 52.9% of patients (109/206) and 29.3% of vessels (181/618). At 4.7 years median follow-up the incidence of the primary endpoint in vessels with significant FFRCT-APPROACH was 58.9% (96/163) which was comparable with vessels with significant FFRCT (55.2%,100/181; P=0.50). The predictive value of FFRCT-APPROACH for the primary endpoint was comparable with FFRCT (AUC 0.72 [95% CI 0.65–0.79] vs 0.71 [0.63–0.78], P=0.79). When combined, there was significant predictive improvement compared with FFRCT alone (AUC 0.77 [0.70–0.84]; P=0.01). The largest incremental benefit upon FFRCT was observed in vessels with FFRCT values in the grey zone between 0.70–0.80 (AUC 0.76 [0.65–0.86] vs 0.62 [0.48–0.74]; P<0.01). Each 10% increase in FFRCT-APPROACH (Adjusted-HR 1.36; 95% CI 1.16–1.60; P<0.001) and each 0.05-unit FFRCT decrease (Adjusted-HR 1.42; 1.19–1.70; P<0.001) were independently associated with significant increase in the incidence of the primary-endpoint.

Conclusion

In patients with stable CAD referred for ICA, the burden of ischaemic myocardium subtended by FFRCT significant vessels predicted non-fatal myocardial infarction and future revascularisation. This provided significant incremental benefit when used in combination with FFRCT particularly at FFRCT values in the grey zone between 0.7 to 0.8.

P985The long-term impact of maintaining sinus rhythm on the risk for death or heart failure after catheter ablation for atrial fibrillation in a real world clinical practice

Background

Catheter ablation has been rapidly spread as a first line therapy for atrial fibrillation (AF). A recent randomized trial have shown that AF ablation reduces the risk of death or hospitalization for heart failure (HF). However, the impact of maintained sinus rhythm (SR) on long-term risk of death or HF hospitalization has not been adequately evaluated.

Purpose

To investigate the impact of maintaining SR by AF ablation on long-term risk of all-cause death or HF hospitalization.

Methods

The long-term clinical outcomes were compared between patients with maintained SR and those with recurrent AF using a landmark analysis in which the landmark point was set at 1.5-year after the 1st ablation.

Results

Among consecutive 1467 patients who underwent AF ablation in our institution between February 2004 and December 2017, the study population consisted of 1311 patients after excluding 150 patients because of death or lost to follow-up. Mean age was 67.9±0.3 and paroxysmal AF was 67%. Among 460 patients who had AF recurrence within 1.5 years after the 1st ablation, 328 underwent 2nd ablation. Therefore, at 1.5-year after the 1st AF ablation, 1145 patients had maintained SR rhythm (SR-group), and 166 patients had recurrent AF episodes (AF-group). During 4.7±2.4 years of follow-up, the cumulative 5-year incidence of death or HF beyond 1.5 years after the 1st ablation was 5.1% in SR-group and 15.6% in AF-group (log rank P<0.001). After adjusting for baseline confounders, the lower risk of SR-group relative to AF-group for death or HF was still statistically significant (HR: 2.05, 95% CI: 1.11–3.58, P=0.02).

Risks for a Composite of Death or HF Hazard Ratio (95% CI) Crude HR P value Adjusted HR P value AF recurrence 2.59 (1.43–4.43) 0.002 2.05 (1.11–3.58) 0.02 Age>75 years old 2.55 (1.56–4.10) <0.001 2.32 (1.39–3.81) 0.002 Female 0.85 (0.49–1.43) 0.56 0.73 (0.40–1.25) 0.26 PeAF 1.25 (0.68–2.16) 0.45 0.98 (0.52–1.75) 0.94 LSAF 1.10 (0.46–2.23) 0.82 0.70 (0.28–1.53) 0.39 LVEF>50% 0.27 (0.16–0.48) <0.001 0.57 (0.31–1.09) 0.09 Past history of HF 7.06 (4.18–11.6) <0.001 4.67 (2.51–8.41) <0.001 CKD 4.74 (2.08–9.39) <0.001 2.23 (0.94–4.69) 0.07 AF, Atrial fibrillation; PeAF, Persistent AF; LSAF; Long standing AF; HF, Heart failure; CKD, Chronic kidney disease.

Figure 1

Conclusions

Successfully maintained SR was associated with reduced long-term risk for death or HF hospitalization in real world patients undergoing AF ablation.