P5626The clinical impact of the angle of OCT detected irregular protrusion after primary PCI at the STEMI culprit lesions

Background and introduction

The percutaneous coronary intervention (PCI) for acute coronary syndrome (ACS) shows worse clinical outcomes than that for stable angina. As the one of the reasons, a recent optical coherence tomography (OCT) registry showed that the presence of irregular protrusion (IP)after coronary stenting was the worse predictor of 1-year device-oriented clinical end points. However, the impact of the quantitative findings on IP has not been well investigated in ACS patients.

Aim

To investigate the clinical impact of the post stent OCT findings, especially IP, detected by OCT after coronary stenting in ACS patients.

Methods

Consecutive 256 ACS lesions treated with OCT-guided PCI in our Medical University Hospital from January 2013 to November 2016 was retrospectively analyzed. In 256 lesions, 173 lesions were enrolled which had ST-elevation acute myocardial infarction (STEMI) with the onset to recanalization time within 720 minutes. In 170 lesions, the OCT images were available. In OCT image, IP was detected in 140 lesions (82.3%). Quantitative analysis of IP in post-procedure OCT imaging was observed to identify the OCT predictors for clinical endpoint including cardiac death, target vessel revascularization ant stent thrombosis in 1 year after index PCI.

Result

In post-procedure OCT findings, stent edge dissection was detected in 32.4% of lesions. Incomplete stent apposition was detected in 74.1%. Maximum angle of irregular protrusion was 194±86 degree and the incidence of maximum IP angle >180 degree was 52.9%. Maximum height of IP was 0.26±0.11mm. Small minimal stent area, defined as a lesion with minimal stent area <5.0 mm2 in a drug-eluting stent or <5.6 mm2 in a bare metal stent, was observed in 32.4% of lesions. Maximum IP angle and that of >180degree was significantly associated with the clinical endpoint (p=0.0259 and 0.0429, respectively).

Conclusion

In STEMI patients, IP was frequently observed in post-procedure OCT imaging during primary PCI. The maximum angle of IP was significantly associated with the clinical end points. The prognostic impact of maximum IP angle in STEMI patient needs further investigations.

129Elevated plasma xanthine oxidoreductase activity predicts cardiovascular events in patients with heart failure with preserved ejection fraction

Background

The pathophysiology of heart failure with preserved ejection fraction (HFpEF) remains poorly understood, although reactive oxygen species (ROS) is reportedly involved in underlying mechanisms. Xanthine oxidoreductase (XOR) is the rate-limiting enzyme of purine metabolism that plays an important role in producing uric acid, and also generates the ROS. However, the impact of plasma XOR activity on the clinical outcomes in patients with HFpEF remains unclear.

Purpose

The aim of this study was to assess whether plasma XOR activity predicts cardiovascular events in patients with HFpEF.

Methods and results

We measured plasma XOR activity in 257 patients with HFpEF. The patients were divided into 3 groups based on XOR activity: low XOR group (<33 pmol/h/mL, n=45), normal XOR group (33 - 120 pmol/h/mL, n=160), and high XOR group (≥120 pmol/h/mL, n=52). During a median follow-up period of 809 days, there were 74 major adverse cardiovascular events (MACEs). Kaplan-Meier analysis demonstrated that the patients with high XOR activity were at greatest risk for MACEs. A multivariate Cox proportional hazard regression analysis showed that high XOR activity was significantly associated with MACEs after adjustment for confounding factors. Furthermore, we divided the patients into 4 groups according to the presence of high XOR activity and/or hyperuricemia. Cox multivariate hazard regression analysis revealed that the patients with high XOR activity were associated with cardiovascular events in patients with HFpEF, regardless of whether hyperuricemia was present or not.

Conclusions

Elevated plasma XOR activity is significantly associated with adverse clinical outcomes in patients with HFpEF. Inhibition of XOR could be a potential therapy for HFpEF.

P1626MicroRNA-21 deteriorates left ventricular reverse remodeling by promoting cardiac fibrosis in non-ischemic cardiomyopathy

Background

Left ventricular reverse remodeling (LVRR) contributes to better outcomes in patients with non-ischemic cardiomyopathy (NICM). It is reported that LVRR is associated with progression of cardiac fibrosis. MicroRNAs (miRs) have emerged as powerful regulators of post-transcriptional gene expression. We focused on miR-21, which plays a key role in pathogenesis of fibrosis in multiple organs. The aim of this study was to clarify the effect of miR-21 on cardiac fibrosis and LVRR in patients with NICM.

Methods

We measured plasma miR-21 levels in 16 patients with NICM. LVRR was defined as increased LVEF by ≥10% and decreased LV end-diastolic diameter index by ≥10% from baseline data after optimal medication treatment at 1-year of follow-up. Further, we examined miR-21 expression and its potential role in cardiac fibrosis induced by transverse aortic constriction (TAC) in mice and angiotensin II (Ang II) stimulation in neonatal rat cardiomyocytes (NRCMs).

Results

There were 12 patients without LVRR and 4 patients with LVRR. Plasma miR-21 levels were significantly higher in patients without LVRR compared with those with LVRR. In TAC mice heart, miR-21 levels were significantly increased and programmed cell death 4 (PDCD4), a main target of miR-21, was decreased. In vitro, miR-21 levels were significantly increased and its upstream transcriptional factor, activator protein 1 (AP-1), was activated by Ang II stimulation in NRCMs. After transfection of miR-21 specific inhibitor, PDCD4 levels were upregulated. Furthermore, AP-1 activity, expression of collagen type I, and α-smooth muscle actin levels were significantly decreased after miR-21 inhibition.

Conclusions

These findings suggested that miR-21/PDCD4/AP-1 feedback loop pathway was involved in LVRR in patients with NICM by promoting cardiac fibrosis. MiR-21 can be the therapeutic target in NICM.

P3355Stress-induced left ventricular dyssynchrony predicts future cardiac events in patients with known or suspected coronary artery disease

Background

Prognostic value of stress induced left ventricular (LV) dyssynchrony has not been fully understood.

The aim of this study was to evaluate the possible impact between cardiovascular events and stress induced worsening LV dyssynchrony.

Methods and results

One hundred and eighty consecutive subjects with known or suspected coronary artery disease (CAD) (142 men, mean age 68±12 years) underwent both gated myocardial single photon emission computed tomography (SPECT) with 99mTc-sestamibi or tetrofosmin according to a standard same day stress-rest protocol and coronary angiography or coronary computed tomography. The summed difference score (SDS) was calculated in every subjects. LV ejection fraction (EF) and phase Entropy at after stress and rest were determined by cardioREPO software. We determined %ΔEntropy = (stress Entropy - rest Entropy)/rest Entropy x100, as an indicator of stress-induced LV dyssynchrony. In the study population, the mean SDS was 2.7±3.9 and LVEF was 58±16%, stress and rest Entropy were 0.62±0.15 and 0.57±0.13, respectively.

%ΔEntropy was higher in patients with CAD than in those without CAD (3.3±11.5 vs. 10.2±15.0, respectively). Moreover, there was a strict correlation between the presence of CAD and %ΔEntropy, indicator of stress induced LV dyssynchrony (non-CAD vs. CAD and/or 1 vessel disease vs. multivessel disease: 4.3±12.5 vs. 8.8±15.6 vs. 12.7±14.3, respectively. p<0.05)

We examined all study subjects and they were divided into 2 groups by cut off value of the %ΔEntropy constructed with receiver operating characteristic curve (=15.4). Kaplan-Meier analysis revealed that future cardiovascular event rate was significantly higher in %ΔEntropy >15.4 group (20/57) than in %ΔEntropy <15.4 group (24/123) (Log-rank p<0.01). On the other hand, summed stress score and SDS were no significant differences between 2 groups.

However, SDS was higher in patients with future cardiovascular event than in those without cardiovascular event (4.4±5.4 vs. 2.2±3.2, respectively. p=0.001).

Conclusion

In patients with known or suspected CAD, stress-induced worsening LV dyssynchrony may predict the presence of CAD and future cardiac events.

Acknowledgement/Funding

None

P4341Sex differences in the U-shaped relationship between physical activity and cardiovascular mortality in the general population

Background

The beneficial effect of moderate physical activity on morbidity and mortality has been observed in the general population. However, sex differences in the impact of physical activity on cardiovascular mortality remain unclear. The aim of this study was to investigate the relationship between physical activity and cardiovascular mortality in the general population.

Methods

This longitudinal cohort study included 1,826 apparently healthy subjects who participated in a community-based health checkup.

Results

There were 97 deaths, including 31 cardiovascular deaths during 10-year follow-up. Subjects were divided into 4 groups based on the quartiles of physical activity (low, mild, moderate and high). There was a U-shaped relationship between physical activity and cardiovascular mortality in male subjects, but not in female subjects. Kaplan-Meier analysis demonstrated that high and low physical activity groups showed higher cardiovascular mortality compared with mild and moderate physical activity groups in male subjects. Cox proportional hazard analysis revealed that low and high physical activities were associated with cardiovascular mortality (hazard ratio 3.59 and 5.11, respectively) in male subjects. In contrast, physical activity was not associated with cardiovascular mortality in female subjects.

Conclusion

We identified a U-shaped relationship between the amount of physical activity and cardiovascular mortality in male subjects, but not in female subjects.

5945Single nucleotide polymorphisms of PAR2 gene is associated with subclinical myocardial damage in the general population

Introduction

The protease activated receptor (PAR) 2 is a G protein-coupled receptor and expressed in cardiomyocytes, vascular cells, and leukocytes. Experimental studies demonstrated that PAR2 signaling is associated with adverse cardiac remodeling, heart failure, vascular inflammation and atherosclerosis. Recently, we and others demonstrated that subclinical myocardial damage is associated with cardiovascular mortality in general population. However, the impact of single nucleotide polymorphisms (SNPs) of PAR2 gene on subclinical myocardial damage in general population is unclear.

Purpose

The aim of this study was to investigate whether SNPs of PAR2 gene is associated with subclinical myocardial damage in general population.

Methods

The present study included 2,926 apparently healthy subjects (aged ≥40) who participated in a community-based health checkup. We investigated 639 SNPs and measured serum heart-type fatty acid binding protein (H-FABP) as markers of subclinical myocardial damage.

Results

We found the association of SNPs rs616235 within a PAR2 gene with subclinical myocardial damage. The homozygous A-allele (AA), heterozygous (AG), and homozygous G-allele (GG) carriers of rs616235 were identified in 2084 (71%), 791 (27%), and 51 (2%) subjects, respectively. The prevalence rates of subclinical myocardial damage were 29% in AA carriers, 23% in AG carriers, and 18% in GG carriers. Multivariate logistic analysis showed that the homozygous (AA) of rs616235 was independently associated with subclinical myocardial damage (odds ratio: 1.330, 95% confidence interval: 1.077–1.641, P=0.0080) after adjustment for conventional cardiovascular risk factors.

Conclusions

Genetic variant of PAR2 gene was independently associated with subclinical myocardial damage in the general population.

P1493Prognostic significance of right ventricular function during exercise in patients with non-obstructive hypertrophic cardiomyopathy

Background

Hypertrophic cardiomyopathy (HCM) is a heterogeneous condition that may present crucial complication including life-threatening arrhythmia and sudden cardiac death. However, the risk stratification of HCM without left ventricular outflow tract (LVOT) obstruction had not been fully elucidated. Moreover, although recent studies have revealed the right ventricle (RV) involvement of HCM, the prognostic importance of RV function during exercise is unclear.

Purpose

To investigate the prognostic significance of RV function in patients with non-obstructive HCM using exercise stress echocardiography (ESE).

Methods and results

This study conducted on 100 HCM patients (age 62.9±13.6 years, 63% men) with preserved left ventricular ejection fraction who underwent ESE using semi-supine bicycle ergometer. Ten patients with significant LVOT obstruction (≥30mmHg) were excluded and 9 were also excluded because of the inadequate imaging quality or insufficiency of data. Among remaining 81 non-obstructive HCM patients, 9 patients suffered from HCM related cardiac events including cardiac death, unexpected hospitalization, life-threatening arrhythmias, and new-onset of syncope during the mean follow up period of 2.6±1.6 years. A multivariate Cox Hazard analysis revealed that low tricuspid annular plane systolic excursion during exercise (Ex-TAPSE, cut-off: 24mm) was an independent predictor of cardiac events. (hazard ratio: 18.66, 95% confidence interval: 3.66–338.46, P<0.001) The estimated cumulative cardiac event free survival using the Kaplan-Meier method was significantly lower in patients with reduced Ex-TAPSE (<24mm) than those with preserved Ex-TAPSE (Log-rank, P<0.01).

K-M curve according to Ex-TAPSE

Conclusion

Ex-TAPSE had a strong predictive value of clinical outcomes in non-obstructive HCM patients. Right ventricular function during exercise may have crucial role in the risk stratification of non-obstructive HCM.

P2462Left atrial appendage wall velocity evaluated by transthoracic echocardiography is a feasible parameter for predicting cardiac prognosis in patients with heart failure

Background

It was reported that left atrial (LA) remodeling is occurred in patients with heart failure (HF), and increased LA volume index (LAVI) is a feasible predictor for poor prognosis of HF. It was reported that LA remodeling is associated with LA appendage (LAA) dysfunction. We previously reported that LAA wall motion velocity (LAWV) obtained by transthoracic echocardiography (TTE) can noninvasively evaluate LAA dysfunction. However, it remains to be determined whether LAWV is useful for predicting poor prognosis in patients with HF.

Purpose

We investigated whether LAA dysfunction assessed by LAWV is associated with poor prognosis in patients with HF.

Methods

We performed TTE at discharge in 217 consecutive patients who hospitalized for HF (126 males, 71±13 years) and prospectively followed them up. LAWV was measured using Doppler tissue imaging at the LAA tip from the parasternal short-axis view on TTE imaging.

Results

There were 86 patients with cardiac events including 14 cardiac deaths and 72 rehospitalizations for HF during a median follow-up period of 404 days (interquartile range 168–748 days). LAWV was significantly lower in patients with cardiac events than in those without. LAWV was significantly decreased with advancing left ventricular diastolic dysfunction grade. Kaplan-Meier analysis demonstrated that significantly higher cardiac event rate was observed in patients with low LAWV (log-rank test, P=0.004). Cox multivariate hazard analysis revealed that LAWV was an independent predictor for cardiac events after adjusting for confounding factors (hazard ratio 0.57, 95% confidence interval 0.40–0.82, P<0.05). Further, we categorized the patients into 3 groups based on the median of LAWV and left atrial volume index (LAVI), and Kaplan-Meier analysis showed that patients with both low LAWV and high LAVI had the highest rate of cardiac events among 3 groups (log-rank test, P<0.001; Figure).

Figure 1

Conclusion

LAWV may be a feasible parameter for predicting cardiac prognosis in patients with HF.

P2528Responsiveness to nutritional intervention would impact on future cardiovascular prognosis in poor fitness patients

Purpose

Nutritional improvement has been proposed for long-term cardiovascular prognosis as well as fitness recovery. We aimed to examine whether “responsiveness” to nutritional and exercise interventions would impact patients' cardiovascular prognosis even patients in low baseline fitness level.

Methods

We included 254 consecutive patients who participated in the phase II comprehensive cardiovascular rehabilitation (CCR) for at least three months. All patients underwent cardiopulmonary exercise test (CPX) at the initial and completion phases of CCR. Nutritional guidance was periodically performed individually during CCR. Peak oxygen uptake (PVO2) was measured through CPX to evaluate the fitness level, whereas nutritional status was evaluated using the geriatric nutritional risk index (GNRI). Patients were divided into “low fitness” and “normal fitness” groups based on the median of baseline PVO2. Each group was further classified into four categories according to the changes in VO2 and GNRI during CCR: “Both NOT improved”, “Only GNRI improved”, “Only PVO2 improved”, and “Both improved”.

Results

Cox proportional regression analysis showed that the category of “both NOT improved” was an independent predictor for cardiovascular risk among the baseline low fitness group (Hazard ratio: 4.5, p=0.007); whereas no significant difference among the normal fitness group. Kaplan-Meier analysis revealed that the event-free survival rate was significantly lower in the “both NOT improved” category (log rank p=0.002) among the baseline low fitness group (figure); whereas no significant difference among the normal fitness group.

GNRI/PVO2 improvement vs. prognosis

Conclusion

Responsiveness to nutritional and exercise intervention could be a predictive factor of cardiovascular prognosis even in low fitness patients.

P1615HECT-Type Ubiquitin E3 Ligase ITCH attenuates cardiac hypertrophy by suppressing Wnt signaling pathway

Background

The homologous to the E6-AP carboxyl terminus (HECT)–type ubiquitin E3 ligase ITCH is an enzyme that plays an important role in ubiquitin proteasomal protein degradation. Dishevelled proteins (Dvl1, Dvl2 and Dvl3), which are involved in canonical Wnt/β catenin signaling pathway, play a role in cardiac hypertrophy.

Purpose

The aim of this study was to examine whether ITCH interacts with Dvls and prevents cardiac hypertrophy induced by pressure overload.

Methods and results

We confirmed the protein interaction between ITCH and Dvls in cardiomyocytes. Overexpression of ITCH decreased protein expression levels of Dvls, phospho-GSK3β and β-catenin. Conversely, knockdown of ITCH using small interfering RNA augmented canonical Wnt/β catenin signaling pathway. Thoracic transverse aortic constriction (TAC) was performed in transgenic mice with cardiac-specific overexpression of ITCH (ITCH-Tg) and wild-type (WT) mice. The canonical Wnt/β catenin signaling pathway was inhibited and cardiac hypertrophy was attenuated in ITCH-Tg mice compared with WT mice after TAC.

Overexpression of ITCH in cardiomyocytes

Conclusion

We demonstrated that ITCH targets Dvls for ubiquitin-proteasome degradation in cardiomyocytes and ameliorates cardiac hypertrophy by suppressing canonical Wnt/β catenin signaling pathway.

In tube immunocytochemistry for fluorescence-activated cell sorting that prevents RNA degradation in sorted cells

Fluorescence-activated cell sorting (FACS) is a powerful tool for analyzing stem cells. When using fixed cells, however, it is sometimes difficult to analyze RNA extracted from sorted cells due to RNA degradation. We established a protocol for immunocytochemistry before FACS to prevent RNA degradation. Cells were fixed with a methanol-based fixative (UM-Fix), then subjected to immunocytochemistry. The addition of RNase inhibitor and dithiothreitol (DTT) to some buffers used for immunocytochemistry increased RNA integrity after cell recovery. We found increased copy numbers of mRNA in recovered cells using quantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis. When RNase inhibitor and DTT were added, amplification of mRNA using T7 promoter was possible with RNA extracted from recovered cells after FACS. Our protocol ensures high quality RNA in cells recovered by FACS; therefore, gene expression analysis with a smaller number of cells is possible using pre-amplification of mRNAs. Our protocol for immunocytochemistry also might be applicable to RNA recovery after immunostaining.

Spinal cord involvement by atrophy and associations with disability are different between multiple sclerosis and neuromyelitis optica spectrum disorder

BACKGROUND AND PURPOSE

The cervical and thoracic cross-sectional spinal cord area (CS-SCA) in multiple sclerosis (MS) correlates with disability, whilst such a correlation remains to be established in neuromyelitis optica spectrum disorder (NMOSD). Our aim was to clarify differences between MS and NMOSD in spinal cord segments where CS-SCA is associated with disability.

METHODS

The CS-SCA at C2/C3, C3/C4, T8/T9 and T9/T10 vertebral disc levels was measured in 140 MS patients (111 with relapsing-remitting MS and 29 with progressive MS) and 42 NMOSD patients with anti-aquaporin-4 immunoglobulin G. Disability was evaluated by Expanded Disability Status Scale (EDSS) scores. Multivariate associations between CS-SCA and disability were assessed by stepwise forward multiple linear regression.

RESULTS

Thoracic CS-SCA was significantly smaller in NMOSD patients than in MS patients even after adjusting for age, sex and disease duration (P = 0.002 at T8/T9), whilst there was no difference in cervical CS-SCA between the two diseases. Cervical and thoracic CS-SCA had a negative correlation with EDSS scores in MS patients (P < 0.0001 at C3/C4 and P = 0.0002 at T8/T9) whereas only thoracic CS-SCA correlated with EDSS scores in NMOSD patients (P = 0.0006 at T8/T9). By multiple regression analyses, predictive factors for disability in MS were smaller cervical CS-SCA, progressive course, older age and a higher number of relapses, whilst those in NMOSD were smaller thoracic CS-SCA and older age.

CONCLUSIONS

Thoracic CS-SCA is a useful predictive marker for disability in patients with NMOSD whilst cervical CS-SCA is associated with disability in patients with MS.