1136Prognostic impact of mineralocorticoid receptor antagonists in patients hospitalized for acute heart failure

Background

The favourable effect of mineralocorticoid receptor antagonists (MRAs) on mortality was established in patients with stable heart failure (HF) with reduced ejection fraction (EF). However, its prognostic effect of MRAs in acute decompensated heart failure (ADHF) including HF with preserved EF (HFpEF) was unclear.

Purpose

This study sought to investigate the long-term impact of MRA on the post-discharge outcomes in patients with ADHF.

Methods

From the consecutive 3717 patients hospitalized for ADHF and discharged alive in the KCHF registry, we developed the propensity score (PS) for MRA use and constructed the PS-matched cohort. We compared the effect of MRA use on the primary outcome measure of all-cause death or HF hospitalization.

Results

A total of 1678 patients (45%) received MRA at discharge from the index hospitalization. Median follow-up was 470 days with 96% 1-year follow-up rate. In the PS-matched cohort (N=1034 in each group), the cumulative 1-year incidence of the primary outcome measure was significantly lower in the MRA group than in the no MRA group (28.4% vs. 33.9%, P=0.003) (Figure 1). The cumulative 1-year incidence of HF hospitalization was significantly lower in the MRA group than in the no MRA group (18.7% vs. 24.8%, P<0.001), while there was no difference in mortality between the 2 groups (15.6% vs. 15.8%, P=0.85). There was no interaction between the effect of MRA and the 3 subgroups stratified by EF (EF <40%, EF 40–49%, EF ≥50%) (interaction P=0.12).

Figure 1

Conclusion

The use of MRA was associated with lower risk for the primary composite outcome of all-cause death or HF hospitalization in patients hospitalized for ADHF including HFpEF, which was mainly driven by the lower risk for HF hospitalization.

P4544Impact of hyponatremia improvement on one-year outcomes in patients with acute decompensated heart failure

Background

Impact of hyponatremia improvement on prognosis in patients with acute decompensated heart failure (ADHF) remains unclear.

Methods

Patients hospitalized for ADHF at 19 hospitals in Japan were enrolled between October 2014 and March 2016. Hyponatremia was defined as serum sodium concentration less than 135 mmol/l. Primary endpoint was composite of all-cause death and heart failure rehospitalization one year after discharge.

Results

Among 3805 patients enrolled, 486 patients with hyponatremia at admission showed higher in-hospital mortality (13.3% vs. 5.4%, p<0.001). Of 486 hyponatremic patients, 396 patients were discharged alive. One hundred forty-three patients showed persistent hyponatremia at discharge (group P), whereas 253 patients showed improvement of hyponatremia (group I). Baseline characteristics are shown in the table. Patients in group I showed higher sodium concentration at admission (132±3 mmol/l vs. 130±4 mmol/l, p<0.001) and more increase in serum sodium concentration at discharge (7±4 mmol/l vs. 1±5 mmol/l, p<0.001). One-year survival rate free from primary endpoint was not different between the groups (56.4% in group P vs. 58.5% in group I, p=0.79). After adjusting for confounders, improvement of hyponatremia was not associated with better prognosis (hazard ratio 1.00; 95% confidence interval 0.70–1.45, p=0.99). Hyponatremia improvement showed significant interaction with left ventricular ejection fraction (LVEF) less than 40% (p=0.01). In patients with LVEF<40%, improvement of hyponatremia was associated with better prognosis (hazard ratio 0.48, 95% confidence interval 0.28–0.85, p=0.01) whereas not in patients LVEF≥40%.

Patient characteristics Group P (n=143) Group I (n=253) p value Age (years) 81 (72–86) 81 (72–87) 0.73 Female 71 (49.7) 110 (43.5) 0.24 Ischemic etiology 42 (29.4) 81 (32.0) 0.58 Prior hospitalization 62 (43.7) 98 (39.5) 0.42 SBP at admission (mmHg) 140±36 144±38 0.40 HR at admission (bpm) 92±23 95±29 0.27 Atrial Fibrillation 47 (32.9) 103 (40.7) 0.12 NYHA class IV 60 (42.2) 138 (54.8) 0.02 Intravenous inotropic use 35 (24.5) 59 (23.3) 0.80 LVEF <40% 54 (37.8) 95 (37.6) 0.97 Values are median (interquartile range), mean ± standard deviation or number (%).

Conclusion

Improvement of hyponatremia at discharge was not associated with better prognosis in patients hospitalized for ADHF.

P5593The association of recurrence and bleeding events with mortality after venous thromboembolism: from the COMMAND VTE Registry

Background/Introduction

Venous thromboembolism (VTE), including pulmonary embolism (PE) and deep vein thrombosis (DVT), has a long-term risk for recurrence, which can be prevented by anticoagulation therapy. The duration of anticoagulation therapy after VTE should be based on the balance between risks of recurrent VTE and bleeding. However, there is uncertainty about the impact of these events on subsequent mortality.

Purpose

We sought to evaluate the impact of recurrent VTE events and bleeding events on subsequent mortality in patients with VTE in a large retrospective observational database in Japan.

Methods

We evaluated the association of recurrent VTE and major bleeding with mortality among 3026 patients in the COMMAND VTE Registry. We estimated the risks of recurrent VTE events and major bleeding events for subsequent all-cause death with the multivariable Cox proportional hazard model. We incorporated the recurrent VTE events and major bleeding events during follow-up into the multivariable Cox model as time-updated covariates together with the clinically-relevant 16 risk-adjusting factors. We expressed the adjusted risks of each covariate as hazard ratios (HR) and their 95%confidence intervals (CI). Furthermore, to assess the risks of recurrent PE and recurrent DVT events for subsequent all-cause death respectively, we divided recurrent VTE events into recurrent PE (PE with or without DVT) and recurrent DVT (DVT only), and incorporated these events as well as major bleeding events into the multivariable Cox model as time-updated covariates.

Results

In the current study population, the mean age was 67 years, 61% were women, and mean body weight and body mass index were 57.9 kg and 23.2 kg/m2, respectively. During the median follow-up period of 1,218 days, 763 patients died, 225 patients developed recurrent VTE events, and 274 patients developed major bleeding events. The time-updated multivariable Cox proportional hazard model revealed that both the recurrent VTE events and the major bleeding events were strongly associated with subsequent mortality risk (recurrent VTE events: HR 3.24, 95% CI 2.57–4.08, P<0.001; major bleeding events: HR 3.53, 95% CI 2.88–4.31, P<0.001). Both the recurrent PE events and the recurrent DVT events were associated with subsequent mortality risk with the numerically greater magnitude of effect with the recurrent PE events than with the recurrent DVT events (recurrent PE events: HR 4.42, 95% CI 3.28–5.95, P<0.001; recurrent DVT events: HR 2.42, 95% CI 1.75–3.36, P<0.001).

Conclusions

In the real-world patients with VTE, both recurrent VTE events and major bleeding events were strongly associated with subsequent mortality risk with the comparable effect size. Recurrent PE and recurrent DVT events were also associated with increased risks for mortality, although the magnitude of the effect on mortality was numerically greater with the recurrent PE events than with the recurrent DVT events.

Acknowledgement/Funding

Research Institute for Production Development, Mitsubishi Tanabe Pharma Corporation

P5652Catheter ablation outcome and heart failure hospitalization in atrial fibrillation patients with preserved left ventricular ejection fraction: insights from the Kansai plus atrial fibrillation (KPAF)

Background

Heart failure (HF) is the leading cause of death in patients with atrial fibrillation (AF), and AF is an independent prognostic factor in HF patients with preserved left ventricular ejection fraction (LVEF). Radiofrequency catheter ablation (RFCA) for AF is effective to maintain sinus rhythm.

Purpose

We sought to clarify incidence of HF hospitalization and whether AF ablation outcome influenced incidence of HF hospitalization after the procedures in patients with preserved LVEF.

Methods

We conducted a large-scale, prospective, multicenter, observational study. A total of 4522 consecutive patients with normal LVEF (>/- 50%) who underwent an initial RFCA for AF in 26 centers were enrolled (average age, 64±10 years; non-paroxysmal AF, 33.7%). The median follow-up duration was 2.9 years.

Results

The 3-year cumulative incidence of AF recurrence after a single procedure was 40.3%. Hospitalization for HF was observed in 60 patients (1.3%) and was significantly higher in patients with AF recurrence than those without it (2.63% vs 0.44%, log-rank p<0.001). After adjustment by age ≥65 years, estimated glomerular filtration rate ≤60ml/min, history of HF, and female, all of which were statistically associated with a risk of HF hospitalization, AF recurrence after the index RFCA was an independent predictor of HF hospitalization (hazard ratio; 4.75, 95% confidence interval; 2.59–9.42, p<0.001).

Conclusions

Recurrence after RFCA for AF was a significant risk of HF hospitalization among AF patients with preserved LVEF.

Acknowledgement/Funding

This study was supported by the Research Institute for Production Development in Kyoto, Japan.

P5025Structural insights into catecholaminergic polymorphic ventricular tachycardia-associated RyR2 mutant channels using a three-dimensional in silico model

Background

The cardiac ryanodine receptors (RyR2) are large tetrameric calcium-permeant ion channels found in cardiac muscle sarcoplasmic reticulum, which play an important role in the control of intracellular Ca2+ release and cardiac contraction. Mutations in the RYR2 gene are associated with lethal arrhythmia diseases including catecholaminergic polymorphic ventricular tachycardia (CPVT) resulting from increased diastolic Ca2+ leak from mutant channels. RyR2 is a huge protein that each subunit of tetramer is comprised of 4967 amino acids, which hampers the detailed in vitro analysis of RyR2 mutant channels.

Purpose

We aimed to analyze the structural features of RyR2 mutant channels identified in our cohort with inherited arrhythmias using RyR2 three-dimensional (3D) in silico model to reveal the arrhythmogenic mechanisms.

Methods

A targeted next-generation sequencing panel for inherited arrhythmias was employed for genetic diagnosis of the patients. Then, we mapped the identified mutations on RyR2 3D structural model developed by cryo-EM images (PDB: 5go9, 5goa, Peng Science 2016) and investigated the relationship between the location of the mutations and specific functional sites.

Results

As a result of genetic analysis, we identified 93 RYR2 mutations from 112 probands with CPVT (n=93) or long-QT syndrome (LQTS) (n=19).64 of 93 (69%) RYR2 mutations are located in three “hot-spot” area (N-terminal (residues 77–466), central (2246–2534), and channel (3778–4959) hotspot. RyR2 3D in silico modeling revealed that the mutations are regionally distributed mainly in three parts: N-terminal, periphery, and channel part (Figure A). In N-terminal part (1–642 amino acid), 9 of 13 mutations alter the charges of the amino acids (Figure B). Especially, R169L, R169Q, and G172E are close to the interface between two neighboring subunits (∼20Å). These mutations which change the amino acid charge may cause a complete disruption of the ionic pair network and result in largest structural changes, which facilitates RyR2 channel opening. In periphery part (643–3528aa), 22 of 33 mutations are close to the two predicted binding sites of FKBP12.6, a stabilizer of RyR2 (∼5–40Å, Figure C). The mutations are supposed to disturb the binding affinity to the FKBP12.6 resulting in RyR2 channel instability. In channel part (3613–4968aa), 16 of 40 mutations are located near two interface. (FigureD) 12 mutations are close to the Ca2+ sensor and the other 4 mutations are adjacent to the pore-forming segment. Especially, V4821I is just located on this segment and strongly expected to impair the channel function. Above all, RyR2 3D in silico modeling revealed that 63 of all 93 (68%) identified mutations are supposed to be pathogenic.

Location of RYR2 mutations in 3D model

Conclusion

3D structural model of RyR2 is useful for the investigation of the pathogenic mechanisms of CPVT-related mutations. Further studies are needed to elucidate the relationship between the location of the mutations and clinical phenotypes.

P5320Reduction in high-sensitivity C-reactive protein by pitavastatin was associated with improved outcomes in Japanese patients with stable coronary artery disease: results from REAL-CAD study

Background

The effect of statins on lowering high sensitivity C-reactive protein (hs-CRP) as well as low density lipoprotein cholesterol (LDL-C) has been associated with reduced risk for cardiovascular events in patients with elevated hs-CRP. However, it remains unclear whether this statin effect applies to low-risk patients with stable coronary artery disease (CAD). In this pre-specified sub-study within the REAL-CAD trial, we explored the association between achieved LDL-C/hs-CRP levels and cardiovascular events in Japanese patients with stable CAD who were treated with pitavastatin 1 mg or 4 mg/day.

Methods

The REAL-CAD trial randomly allocated 13,054 patients with stable CAD to pitavastatin 1 mg or 4 mg/day. LDL-C and hs-CRP were measured at baseline and at 6 months after randomization. We excluded those patients without 6-month data and those with endpoint events before 6 months (N=1915). The primary endpoint of the study was a composite of cardiovascular death, nonfatal myocardial infarction, nonfatal ischemic stroke, or unstable angina requiring emergency hospitalization. Outcomes were assessed by landmark analysis beyond 6 months among 4 groups that were configured based on LDL-C (median) and hs-CRP (median) targets: achieving neither target, achieving LDL-C target only, achieving hs-CRP target only, and achieving both targets. Data were adjusted for baseline characteristics including age, gender, diabetes and baseline values of LDL-C and hs-CRP.

Results

Median LDL-C and hs-CRP levels were 88 mg/dL and 0.52 mg/L at baseline and 80 mg/dL and 0.48 mg/L after 6 months, respectively. There was no correlation between the change in LDL-C and hs-CRP levels from baseline to 6 months (correlation coefficient: 0.009, P=0.331). Of the 11,677 patients included in the study, 25.1% (N=2799) achieved both LDL-C and hs-CRP targets, 25.3% (N=2282) met neither target, 24.8% (N=2765) met only the hs-CRP target, and 24.7% (N=2753) met only the LDL-C target. Risk of primary endpoint occurrence was significantly lower in those achieving either or both targets than in those meeting neither target (Figure A). In the subgroup analysis stratified by the randomized dose of pitavastatin, the risk for the primary endpoint was significantly lower in patients achieving both targets in both the 1mg and 4 mg arms, and in patients achieving only hs-CRP target in the 1 mg arm (Figure B, C).

Figure 1

Conclusions

In this subanalysis of the REAL-CAD trial, the hs-CRP lowering effect of pitavastatin was independent from LDL-C lowering. Lower achieved hs-CRP was associated with lower risk for cardiovascular events in Japanese patients with stable CAD.

Acknowledgement/Funding

Public Health Research Foundation, The company manufacturing the study drug (Kowa Pharmaceutical Co Ltd) was one of the entities providing financial s

P772Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers for heart failure patients with different left ventricular ejection fraction categories: from the KCHF Registry

Background

The current guidelines recommend different medical treatment strategies for heart failure (HF) patients according to category of left ventricular ejection fraction (LVEF). Angiotensin-converting enzyme inhibitors/angiotensin receptor blockers (ACE-I/ARB) is an established medical treatment for heart failure with reduced ejection fraction (HFrEF), whereas its usefulness remains to be elucidated for non-HFrEF, especially for heart failure with mid-range ejection fraction (HFmrEF).

Purpose

This study aimed to assess the difference in association between ACE-I/ARB and clinical outcomes depending on LVEF category.

Methods

The Kyoto Congestive Heart Failure (KCHF) Registry is a multicentre registry without any exclusion criteria which included consecutive patients hospitalized for congestive HF in Japan. In each LVEF group (HFrEF, HFmrEF and heart failure with preserved ejection fraction [HFpEF]), we compared those who were prescribed ACE-I/ARB as discharge medication and those not, and assessed their 1-year clinical outcomes. We defined the primary outcome measure as a composite of all-cause death and HF hospitalization. We constructed a multivariable Cox regression model incorporating 24 clinically relevant factors. We assessed adjusted hazard ratios (HRs) of those with ACE-I/ARB relative to those not, and also interaction between ACE-I/ARB prescription at discharge and LVEF category.

Results

A total of 3717 patients were included in this study, where the number of patients in each LVEF group were as follows; 1383 patients with HFrEF, 703 with HFmrEF and 1631 with HFpEF, respectively (Figure). As shown in the table, the HRs for the primary outcome measure were significant in the HFrEF and HFmrEF groups, whereas the HR in the HFpEF group was insignificant. The interaction between ACE-I/ARB prescription and LVEF category for the primary outcome measure was statistically significant.

Hazard ratios by LVEF category Outcome measures HFrEF HFmrEF HFpEF P interaction HR (95% CI) P value HR (95% CI) P value HR (95% CI) P value All-cause death + HF hospitalization 0.66 (0.54–0.79) <0.001 0.61 (0.45–0.82) 0.001 0.95 (0.80–1.14) 0.61 0.01 All-cause death 0.62 (0.48–0.81) <0.001 0.52 (0.35–0.77) 0.001 0.73 (0.58–0.93) 0.01 0.10 HF hospitalization 0.73 (0.57–0.92) 0.009 0.59 (0.40–0.87) 0.007 1.14 (0.90–1.44) 0.28 0.07 Hazard ratios of ACE-I/ARB relative to non-ACE-I/ARB for primary outcome measures in each LVEF category.

Study flowchart

Conclusions

The risk ratios of those who were prescribed ACE-I/ARB relative to those not were significantly low in HFmrEF as well as HFrEF, whereas the risk ratios were insignificant in HFpEF. ACE-I/ARB could be a potential choice of treatment for HFmrEF patients.

P3847Deep vein thrombosis in upper extremities: clinical characteristics, management strategies and long-term outcomes from the COMMAND VTE Registry

Background/Introduction

Pulmonary embolism (PE) is caused by blockage of pulmonary arteries by thrombus. The sources of thrombus are thought to be mostly veins in lower extremities, whereas deep vein thrombosis (DVT) in upper extremities rarely occurs spontaneously. Recent studies reported that DVT in upper extremities might have significant complications, and DVT in upper extremities could be increasing. However, there is a paucity of data on patients with DVT in upper extremities, leading to uncertainty in optimal treatment strategies including anticoagulation therapy.

Purpose

We sought to evaluate the clinical characteristics, management strategies, and long-term outcomes of patients with DVT in upper extremities in a large observational database in Japan.

Methods

The COMMAND VTE Registry is a multicenter registry enrolling 3027 consecutive patients with acute symptomatic venous thromboembolism (VTE) objectively confirmed by imaging examination or by autopsy among 29 centers in Japan between January 2010 and August 2014. The current study population consisted of 2498 patients with DVT in upper or lower extremities, after excluding 381 patients with PE only, 144 patients who had thrombus in locations other than upper or lower extremities, and 4 patients with DVT in both upper and lower extremities. The study patients were divided into 2 groups: patients with DVT in upper extremities and patients with DVT in lower extremities. We compared the clinical characteristics, management strategies and long-term outcomes between the 2 groups.

Results

There were 74 patients (3.0%) with upper extremities DVT and 2498 patients (97%) with lower extremities DVT. Patients with upper extremities DVT more often had active cancer at diagnosis (58%) and central venous catheter use (22%). The proportion of concomitant PE at diagnosis was lower in patients with upper extremities DVT than in those with lower extremities DVT (14% and 51%, P<0.001). Discontinuation of anticoagulation therapy was more frequent in patients with upper extremities DVT (63.8% and 29.8% at 1-year, P<0.001). The cumulative 3-year incidence of recurrent VTE was not different between the 2 groups (9.8% and 7.4%, P=0.43) (Figure). After adjusting confounders, the risks of upper extremities DVT relative to lower extremities DVT for recurrent VTE remained insignificant (HR 0.94, 95% CI 0.36–2.01, P=0.89).

Kaplan-Meier event curves for recurrence

Conclusions

The prevalence of patients with DVT in upper extremities was 3.0% in the current large-scale real-world registry. Patients with DVT in upper extremities more often had active cancer at diagnosis and central venous catheter use as a transient risk factor for VTE, and less often had concomitant PE. Patients with DVT in upper extremities had similar long-term risk for recurrent VTE as those with DVT in lower extremities despite shorter duration of anticoagulation.

Acknowledgement/Funding

Research Institute for Production Development, Mitsubishi Tanabe Pharma Corporation

Efficacy and Safety of Guselkumab in Japanese Patients With Palmoplantar Pustulosis: A Phase 3 Randomized Clinical Trial

Question

Is guselkumab, an anti–interleukin 23 monoclonal antibody, efficacious and safe in Japanese patients with palmoplantar pustulosis?

Findings

In this 60-week, randomized clinical trial of 159 patients with palmoplantar pustulosis, palmoplantar pustulosis area and severity index score was overall improved after subcutaneous injection of guselkumab, 100 mg and 200 mg or placebo; however, in the 200-mg group, the proportion of patients who achieved 50% or more reduction in palmoplantar pustulosis area and severity index score at week 16 was not significantly greater compared with placebo. Efficacy end points improved consistently through week 52, and health-related quality of life also improved significantly.

Meaning

Guselkumab may be an effective and safe treatment option for management of palmoplantar pustulosis.

Importance

Palmoplantar pustulosis (PPP) causes erythematous, scaly plaques with recurrent sterile pustules refractory to treatment and with few randomized clinical trials conducted. Evidence points to involvement of interleukin 23 in the pathogenesis of PPP.

Objective

To determine the efficacy and safety of guselkumab, an anti–IL-23 monoclonal antibody, in Japanese patients with PPP.

Design, Setting, and Participants

A phase 3 randomized clinical trial was conducted from December 15, 2015, to December 12, 2017. A total of 159 enrolled patients (aged ≥20 years) had an inadequate response to conventional therapies, with a diagnosis of PPP for 24 or more weeks before screening. Intention-to-treat analysis was performed.

Interventions

Subcutaneous injections of guselkumab, 100 or 200 mg, at weeks 0, 4, and 12, and every 8 weeks thereafter were administered; placebo was given at weeks 0, 4, and 12.

Main Outcomes and Measures

Changes from baseline in PPP Area and Severity Index (PPPASI) score (possible score range, 0-72, with higher scores indicating greater area and severity), PPP severity index (PPSI) score (possible score range, 0-12, with higher scores indicating greater severity), and proportion of PPPASI-50 (≥50% reduction) responders at weeks 16 and 52 were assessed. Safety was monitored through week 52.

Results

A total of 159 patients (mean [SD] age at diagnosis, 46.8 [11.9] years; 126 women [79.2%]) were enrolled. Treatment groups comprised guselkumab, 100 mg (n = 54), guselkumab, 200 mg (n = 52), or placebo (n = 53). Both guselkumab groups demonstrated significant improvement in least-squares mean changes in PPPASI score compared with placebo: −15.3 and −11.7 in the guselkumab 100-mg and 200-mg groups, respectively, and −7.6 in the placebo group (difference [SE] vs placebo: −7.7 [1.7] in the 100-mg group, P < .001; 95% CI, −11.00 to −4.38; and −4.1 [1.7] in the 200-mg group, P < .017; 95% CI, −7.47 to −0.75]). Least-squares mean changes in PPSI score showed significant improvement in both guselkumab groups (100 mg: −2.0 [0.5]; P < .001; 95% CI, −2.96 to −0.95; 200 mg: −1.0 [0.5; P = .04; 95% CI, −2.06 to −0.03). A significantly higher proportion of patients in the guselkumab 100-mg group (31 [57.4%]) achieved a PPPASI-50 response at week 16 vs placebo (18 [34.0%]; P = .02); however, the result was not significant for the guselkumab 200-mg group (19 [36.5%]) vs placebo; P = .78). Each efficacy end point improved consistently through week 52. Health-related quality of life improved significantly as indicated by a reduction in the Dermatology Life Quality Index score (100 mg: −2.6; 95% CI, −4.0 to −1.2; P < .001; 200 mg: −1.6; 95% CI, −3.1 to −0.2; P = .03). Serious treatment-emergent adverse events were observed in 8 patients (placebo group, 2 of 53 [3.8%]; combined guselkumab group, 6/157≠10.5%). No serious infections were reported.

Conclusions and Relevance

Targeting interleukin 23 with guselkumab may be an effective and safe treatment option for a recalcitrant disease such as PPP.

Trial Registration

ClinicalTrials.gov identifier: NCT02641730

P2560Metalloprotease nardilysin controls heart rate through the transcriptional regulation of ion channels critical for sinus automaticity

Acknowledgement/Funding

KAKENHI (17K09575)

4968Increased Gao expression underlies cardiac dysfunction and lethal arrhythmias accompanied with abnormal Ca2+ handling

Background

We previously demonstrated that a transcriptional repressor, neuron restrictive silencer factor (NRSF), maintains normal cardiac function and electrical stability. Transgenic mice expressing a dominant-negative mutant of NRSF in their hearts (dnNRSF-Tg) exhibit systolic dysfunction with cardiac dilation and premature death due to lethal arrhythmias like human dilated cardiomyopathy (DCM). Underlining mechanisms remain to be elucidated, however.

Purpose

We studied underling mechanisms by which NRSF maintains normal cardiac function to identify novel therapeutic targets for heart failure.

Methods and results

We generated cardiac-specific NRSF knockout mice (NRSFcKO) and confirmed that cardiac phenotypes of NRSFcKO are similar to those of dnNRSF-Tg.

cDNA microarray analysis revealed that cardiac gene expression of GNAO1 that encodes Gαo, a member of inhibitory G protein Gαi family, is increased in both dnNRSF-Tg and NRSFcKO ventricles.

We confirmed that GNAO1 is a direct target of NRSF through ChIP-seq analysis, reporter assay and electrophoretic mobility shift assay.

In dnNRSF-Tg, pharmacological inhibition of Gαo with pertussis toxin improved systolic dysfunction and knockdown of Gαo by crossing with GNAO1 knockout mice improved not only systolic function but also frequency of ventricular arrhythmias and survival rates.

Electrophysiological and biochemical analysis in ventricular myocytes obtained from dnNRSF-Tg demonstrated that genetic reduction of Gαo ameliorated abnormalities in Ca2+ handling, which include increased current density in surface sarcolemmal L-type Ca2+ channel, reduced content of sarcoplasmic reticulum Ca2+ and lowered peak of Ca2+ transient. Furthermore, genetic reduction of Gαo attenuated increased phosphorylation levels of CAMKII in dnNRSF-Tg ventricles, which presumably underlies the improvement in Ca2+ handling. In addition, we identified increased Gαo expression in ventricles of heart failure model mice induced by transverse aortic constriction and cardiac troponin T mutant DCM model mice, in both of which, genetic reduction of Gαo ameliorated cardiac dysfunction.

Figure 1

Conclusions

We found that increased expression of Gαo, induced by attenuation of NRSF-mediated repression, plays a crucial role in the progression of cardiac dysfunction and lethal arrhythmias by evoking Ca2+ handling abnormality. These data demonstrate that Gαo is a potential therapeutic target for heart failure.

P3846The association between statin prescription, recurrent venous thromboembolism and bleeding events: from the COMMAND VTE Registry

Background

Statin prevents occurrence and recurrence of atherosclerotic events. With regard to venous thromboembolism (VTE), a randomized controlled trial suggested that statin reduced occurrence of VTE, whereas its usefulness as secondary prevention of VTE remains to be elucidated.

Purpose

This study aimed to assess the association between statin prescription, recurrent VTE and bleeding events in patients with VTE.

Methods

The COMMAND VTE Registry is a multicentre registry enrolling consecutive 3027 patients with acute symptomatic VTE among 29 centres in Japan. We divided the cohort into the patients who were prescribed statin (N=437) and those not (N=2590), and compared the two groups. We assessed hazard ratios (HRs) of those with statin relative to those without for long-term clinical outcomes (recurrent symptomatic VTE and International Society of Thrombosis and Hemostasis [ISTH] major bleeding). Because the durations of anticoagulation therapy were widely different between the two groups, we constructed Cox's proportional hazard model incorporating status of anticoagulation during the follow-up period as a time-varying covariate. Also, because the incidences of death were strikingly different between the two groups due to the difference in the prevalence of active cancer, we used Fine-Gray's subdistribution hazard model in the presence of competing risks. We incorporated clinically relevant factors into these two models as covariates (10 factors for recurrent VTE and 11 for major bleeding).

Results

The statin group was significantly older than the non-statin group (statin 71.2±11.8 vs. non-statin 66.5±15.8, P<0.001). The prevalence of active cancer in the statin group was less than one-half of that in the non-statin group (12% vs. 25%, P<0.001), and the cumulative 3-year incidence of death was significantly lower in the statin group than in the non-statin group (12.8% vs. 26.1%, log-rank P<0.001). The table shows the adjusted HRs of the statin group relative to the non-statin group. The HRs of the statin group relative to non-statin group for recurrent VTE were significantly low, but those for major bleeding were insignificant.

Adjusted hazard ratios Outcome measures Model 1 P value Model 2 P value Adjusted HR [95% CI] Adjusted HR [95% CI] Recurrent VTE 0.59 [0.36–0.98] 0.042 0.53 [0.32–0.89] 0.02 Major bleeding 0.87 [0.60–1.24] 0.43 0.997 [0.69–1.43] 0.99 Model 1 derived from Cox's model with time-varying covariate of anticoagulation status. Model 2 derived from Fine-Gray's model.

Study flowchart

Conclusions

Prescription of satin was associated with significantly low risks for recurrent VTE, whereas that was not for major bleeding events. Statin could be a potential treatment option for secondary prevention of VTE.

P1029Catheter ablation outcome and heart failure hospitalization in atrial fibrillation patients: insights from the Kansai plus atrial fibrillation (KPAF) registry

Background

Heart failure (HF) is the leading cause of death in patients with atrial fibrillation (AF). Radiofrequency catheter ablation (RFCA) for AF is effective to maintain sinus rhythm.

Purpose

We sought to clarify whether AF ablation outcome influenced incidence of HF hospitalization after the procedures.

Methods

We conducted a large-scale, prospective, multicenter, observational study. A total of 5010 consecutive patients who underwent an initial RFCA for AF in 26 centers were enrolled (average age, 64±10 years; non-paroxysmal AF, 35.6%). The median follow-up duration was 2.9 years.

Results

The 3-year cumulative incidence of AF recurrence after a single procedure was 40.2%. The 3-year incidence of hospitalization for HF was observed in 92 patients (1.8%) and was significantly higher in patients with AF recurrence than those without it (3.3% vs 0.84%, log-rank p<0.001). After adjustment by advanced age,(≥65 years), reduced left ventricular ejection fraction (≤50%), low estimated glomerular filtration rate (≤60ml/min), and history of HF, all of which were statistically associated with a risk of HF hospitalization (p<0.1, respectively), AF recurrence after the index RFCA was an independent predictor of HF hospitalization (hazard ratio [HR]; 3.17, 95% confidence interval [CI]; 2.06–5.04, p<0.001).Even after multiple procedures (1425 re-ablation sessions in 1274 patients [25.4%]), AF recurrence after the last procedure was an independent predictor of HF hospitalization (HR; 2.83, 95% CI; 1.89–4.24, p<0.001).

Conclusions

Among AF patients receiving RFCA, those with AF recurrence were at greater risk of heart failure hospitalization than were patients without AF recurrence. These differences should be noted when treating AF patients in actual clinical practice.

Acknowledgement/Funding

This study was supported by the Research Institute for Production Development in Kyoto, Japan.

P5650Improvement in ejection fraction predicts heart failure after catheter ablation for atrial fibrillation in patients with left ventricular systolic dysfunction: from the KPAF registry

Introduction

The presence of atrial fibrillation (AF) in patients with reduced left ventricular ejection fraction (LVEF) is associated with increased risks of mortality and hospitalization for heart failure (HF). Although prior studies reported that catheter ablation (CA) for AF in low LVEF patients reduced risks of all-cause mortality and HF hospitalization, the predictors of worsening HF after ablation has not been adequately evaluated.

Purpose

The purpose of this study was to investigate the impact of improvement in LVEF after AF ablation on the incidence of subsequent HF hospitalization in patients with low LVEF.

Methods

The Kansai Plus Atrial Fibrillation (KPAF) Registry is a multicenter registry enrolling 5,013 consecutive patients undergoing first-time ablation for AF. The current study population consisted of 1,031 patients with reduced LVEF of <60%. We divided the study population into 3 groups according to LVEF at follow-up; 678 patients (65.8%) with improved LVEF (≥5 U change in LVEF), 288 patients (27.9%) with unchanged LVEF (−5 U ≤ change in LVEF <5 U) and 65 patients (6.3%) with worsened LVEF (<−5 U change in LVEF).

Results

During the median follow-up of 1067 [879–1226] days, patients improved LVEF had lower rate of HF hospitalization, compared with those with unchanged and worsened LVEF (2.1%, 8.0%, and 21.5%, respectively, P<0.0001). Recurrent atrial tachyarrhythmias were documented in 43.5%, 47.2% and 67.7%, respectively (P=0.0008).

Figure 1

Conclusion

Among patients with reduced LVEF undergoing AF ablation, patients with subsequently improved LVEF in association with maintained sinus rhythm had markedly lower risk of HF hospitalization during follow-up as compared with those with unchanged or worsened LVEF.

EFFECT ON MICROBIAL PRODUCTS ON CAESIUM ELUTION BEHAVIOUR FROM CLAY MINERALS

Some microorganisms in the environment make siderophores, which are low molecular chelators, to take up minerals from soil. Eleven bacteria were separated from the root of white clover by chlome azrol S (CAS) assay. Each bacterium was incubated in casamino acid (CAA) culture, and siderophores in CAA culture were purified. These extractions were applied to biotite or vermiculite spiked with Cs. From each clay mineral, 57.1-72.8% (5100 ppm), 55.6-63.8% (920 ppm) and 48.6-54.3% (2300 ppm), 31.6-34.4% (520 ppm) was eluted, respectively. To understand elution behaviour, Cs desorption ratio of each clay was measured every 30 min. The results indicate Cs elution was occurred quickly.

P5592Thrombolysis with tissue plasminogen activator for patients with acute pulmonary embolisms in the real world: from the COMMAND VTE Registry

Background/Introduction

There is still uncertainty about the optimal usage of thrombolysis for acute pulmonary embolisms (PEs), leading to widely varying usage of thrombolysis in the real world. However, these have not been fully evaluated yet.

Purpose

We sought to evaluate the management strategies and clinical outcomes of thrombolysis for acute PEs in the real world.

Methods

The COMMAND VTE Registry is a multicenter registry enrolling 3,027 consecutive patients with acute symptomatic venous thromboembolisms in Japan between January 2010 and August 2014. The present study population consisted of 1,549 patients with PEs who received tissue plasminogen activator (t-PA) thrombolysis (N=180, 12%), or those who did not (N=1,369). The effectiveness outcome was all-cause death. The safety outcome was major bleeding. We used a multivariable logistic regression analysis to estimate the odds ratio (OR) and 95% confidence intervals (CI), to adjust clinically relevant confounders (age, sex, history of major bleeding, active cancer, and anemia). Additionally, we conducted stratified analysis by clinical severity, and we also evaluated clinical outcomes according to dosages of t-PA.

Results

Patients with t-PA thrombolysis were younger, and more frequently had higher body weight, but less frequently had active cancer, history of major bleeding, and anemia. More than half of patients with t-PA thrombolysis were patients with mild PEs, and the proportions of t-PA thrombolysis varied widely across the participating centers. More than half of patients received low-dose of t-PA (<20,000 IU/kg). As for the effectiveness, 9 (5.0%) patients in the t-PA thrombolysis group and 95 (6.9%) patients in the non t-PA thrombolysis group died at 30 days (Crude OR, 0.71; 95% CI 0.35–1.42, P=0.33). As for the safety, 7 (3.9%) patients in the t-PA thrombolysis group and 22 (1.6%) patients in the non t-PA thrombolysis group experienced major bleeding events at 10 days (Crude OR, 2.48; 95% CI 1.04–5.88, P=0.04). T-PA thrombolysis group had a significantly higher risk for 10-day major bleeding (Adjusted OR, 4.01; 95% CI 1.57–10.2, P=0.004), but not a lower risk for 30-day mortality (Adjusted OR, 1.10; 95% CI 0.53–2.28, P=0.79), although the risk for 30-day mortality was significantly lower in those with severe PEs (Adjusted OR, 0.36; 95% CI 0.15–0.88, P=0.02). After adjusting confounders, the 10-day major bleeding risk of the low-dose of t-PA group relative to the standard-dose of t-PA group tended to be lower (Adjusted OR, 0.07; 95% CI 0.004–1.05, P=0.05).

Conclusions

In the present real-world registry, relatively large number of patients received t-PA thrombolysis with wide variation across the participating centers. T-PA thrombolysis was significantly associated with a higher risk for major bleeding, but not a lower risk for mortality, although there appeared to be a benefit of t-PA thrombolysis in decreasing the risk for mortality in patients with severe PEs.

Acknowledgement/Funding

Research Institute for Production Development, Mitsubishi Tanabe Pharma Corporation

P6461The long-term clinical comparisons of symptomatic patients of pulmonary embolism with and those without deep vein thrombosis: from the COMMAND VTE Registry

Background

Venous thromboembolism (VTE), including pulmonary embolism (PE) and deep vein thrombosis (DVT), has significant morbidity and mortality. Acute PE, in particular, is fatal if we miss it, and symptomatic patients of PE sometimes have concomitant DVT.

Purpose

This study compared the risk of mortality in symptomatic patients of PE with and those without DVT in the long term.

Methods

The COMMAND VTE Registry is a multicenter registry enrolling consecutive 3027 patients with acute symptomatic VTE objectively confirmed by imaging examination or by autopsy among 29 centers in Japan between January 2010 and August 2014. Patients with both PE and DVT (N=1334) were regarded as PE patients, and the current study population consisted of 1715 PE patients and 1312 DVT patients.

Results

There were 1203 symptomatic patients of PE, including 381 without and 822 with DVT. In our cohort, the mean age was 67.9±14.9 years, 63% was female, 44% had hypertension, 12% diabetes mellitus, 5% history of VTE. There were 20% of active cancer. Baseline characteristics were well matched except for dyslipidemia (18% vs. 23%, p=0.021) and atrial fibrillation (8% vs. 5%, p=0.045). Patients without DVT had a more severe clinical presentation compared to those with DVT, including hypoxemia, shock and arrest. Moreover, Initial parenteral anticoagulation therapy in the acute phase was administered less frequently in patients without DVT (89% vs. 96%, P=0.0001). Two groups received thrombolysis (20% vs. 26%, P=0.18) and mechanical supports (Ventilator 14% vs. 5%, p<0.001, PCPS 5% vs. 3%, p<0.001, respectively). During follow-up, 93 (8%) patients experienced recurrent VTE events and 98 (8%) major bleeding events, and 323 (27%) patients died. The most frequent cause of death was cancer (11%). There were a significant differences in the cumulative incidences of all-cause death between the groups (32% vs. 24%, P=0.006), whereas there was significant difference in VTE-related death (13% vs. 4%, p<0.001). Estimated freedom rates from death for patients of PE without and those with DVT were as follows: 88% vs 99% at 10-day, 86% vs 95% at 1-month, 75% vs 83% at 1-year, and 64% vs 71% at 5-year, respectively.

Landmark analysis

Conclusions

In symptomatic patients of PE, there was a difference in mortality between groups, but no difference in recurrent VTE. Patients without DVT had a more severe clinical presentation compared to those with DVT, and many VTE-related deaths in the acute phase. The one-month mortality rate differed statistically between groups, but there was no significant difference in long-term survival beyond one month. Most of deaths were due to underlying diseases, mainly cancer, and less commonly due to VTE in the long term.

Acknowledgement/Funding

Research Institute for Production Development, Mitsubishi Tanabe Pharma Corporation

P2770Clinical characteristics and outcomes of venous thromboembolism according to patients with versus without atrial fibrillation: from the COMMAND VTE Registry

Background/Introduction

Oral anticoagulants are widely used for the treatment and second prevention of venous thromboembolism (VTE) and stroke prevention in atrial fibrillation (AF). VTE and AF are common diseases and these sometimes might coexist. However, there are few reports about the relationship between VTE and AF.

Purpose

We sought to evaluate the clinical characteristics and outcomes in VTE patients with AF.

Methods

The COMMAND VTE Registry is a multicenter registry enrolling consecutive 3027 patients with acute symptomatic VTE objectively confirmed by imaging examination or by autopsy among 29 centers in Japan between January 2010 and August 2014. The current study population consisted of 129 patients with AF (AF group) and 2898 patients without AF (non-AF group). We compared the clinical characteristics, management strategies and long-term outcomes between the 2 groups.

Results

The AF group was older (mean age: 75.3 vs. 66.8 years, P<0.001), and more often had co-morbidities such as hypertension (54.3% vs. 37.7%, P<0.001), diabetes mellitus (20.2% vs. 12.4%, P=0.01), chronic kidney disease (28.7% vs. 18.5%, P=0.004), heart failure (28.7% vs. 18.5%, P=0.004), history of stroke (20.2% vs. 8.4%, P<0.001), and history of major bleeding (12.4% vs. 7.4%, P=0.04) compared with the non-AF group, whereas there were no significant differences in the proportions of active cancer at diagnosis (18.6% vs. 23.2%, P=0.23) and pulmonary embolism at presentation (64.3% vs. 56.3%, P=0.07). The proportion of anticoagulation therapy beyond acute phase was not significantly different (94% vs. 93%, P=0.60), while the cumulative discontinuation rates of anticoagulation therapy was significantly lower in the AF group (26.9% vs. 43.4% at 3 years, Log-rank P=0.03). The cumulative 5-year incidences of recurrent VTE and major bleeding were not significantly different (Recurrent VTE: 7.6% vs. 10.6%, Log-rank P=0.89; Major bleeding: 18.6% vs. 11.8%, Log-rank P=0.07). After adjusting for potential confounders, the risks of the AF group relative to the non-AF group for recurrent VTE and major bleeding remained insignificant (HR 1.19, 95% CI 0.54–2.28, P=0.64; HR 1.28, 95% CI 0.73–2.06, P=0.37). The cumulative 5-year incidence of all-cause death was significantly higher in the AF-group (49.1% vs. 28.6%, Log-rank P<0.001). After adjusting for potential confounders, the risks of the AF group relative to the non-AF group for all-cause death remained significant (HR 1.63, 95% CI 1.23–2.15, P<0.001). The proportion of deaths due to cancer was lower in the AF group (30% vs. 55%, P<0.001), while the proportion of cardiac deaths was higher in the AF group (16.1% vs. 4.0%, P<0.001).

The outcomes of VTE patients with AF

Conclusions

The risks for recurrent VTE between patients with AF and those without AF were not significantly different, although patients with AF received longer-term anticoagulation therapy, whereas the risks for major bleeding tended to be higher in patients with AF.

Acknowledgement/Funding

Research Institute for Production Development, Mitsubishi Tanabe Pharma Corporation

Toward Atomistic Modeling of Irreversible Covalent Inhibitor Binding Kinetics

Covalent inhibitors have emerged as an important drug class in recent years, largely due to their many unique advantages as compared to noncovalent inhibitors, including longer duration of action, lower prolonged systemic exposure, higher potency, and selectivity. However, the potential off-target toxicity of covalent inhibitors, particularly of irreversible covalent inhibitors, represents a great challenge in covalent drug development. Therefore, accurate calculation of protein covalent inhibitor reaction kinetics to guide the design of selective inhibitors would greatly benefit covalent drug discovery efforts. In the present paper, we present a computational method to calculate the relative reaction kinetics between congeneric irreversible covalent inhibitors and their protein receptors. The method combines density functional theory calculations of the transition state barrier height of the rate-limiting step for reaction between the warhead of the inhibitor and a single protein residue, and molecular-mechanics-based free energy calculations to account for the interactions between the ligand in the transition state and the protein environment. The method was tested on four pharmaceutically interesting irreversible covalent binding systems involving 28 ligands; the mean unsigned error (MUE) of the relative reaction rate for all pairs of ligands between the predictions and experimental results for these tested systems is 0.79 log unit. This is to our knowledge the first time where the reaction kinetics of protein irreversible covalent inhibition have been directly calculated with physics-based free energy calculation methods and transition state theory. We anticipate the outstanding accuracy demonstrated here across a broad range of target classes will have a strong impact on the design of selective covalent inhibitors.