Recurrence of atrial fibrillation after catheter ablation is associated with major adverse cardiac and cerebrovascular events: insights from AF frontier ablation registry

Background

Recent observational studies have suggested that catheter ablation for atrial fibrillation (AF) is significantly associated with reduced risk for stroke, cardiovascular events and all-cause death. However, little is known whether late recurrence of AF after catheter ablation is associated with worse clinical outcomes.

Purpose

We aimed to clarify whether late recurrence of AF after catheter ablation is associated with major adverse cardiac and cerebrovascular events (MACCE).

Methods

We retrospectively investigated 2,737 participants (74.4% men, mean age 63.4±10.3 years, 62.7% paroxysmal AF) who received first catheter ablation for AF and completed follow-up more than 3 months after the procedure from AF Frontier Ablation Registry, a multicenter cohort study in Japan. We evaluated an association between late recurrence of AF after catheter ablation and first MACCE in cox-regression hazard models adjusted for known risk factors. MACCE were defined as stroke/transient ischemic attack (TIA), cardiovascular events or all-cause death. Late recurrence was defined as AF relapse more than 3 months after the procedure.

Results

During a mean follow-up period of 25.2 months, 2,070 patients (75.6%) were free from AF after catheter ablation and 122 patients (4.5%) had MACCE (ischemic stroke 18 [14.8%], hemorrhagic stroke 16 [13.1%], TIA 7 [5.7%], hospitalization for heart failure 19 [15.6%], acute coronary syndrome 19 [15.6%], hospitalization for other cardiovascular events 24 [20%] and all-cause death 19 [15.6%]). The MACCE occurred significantly more frequently in the recurrence group than in non-recurrence group (7.5% vs. 3.5%; hazard ratio [HR] 1.85; 95% confidence interval [CI] 1.28–2.65; P=0.001) (Figure). Multivariate analysis revealed that baseline age (HR 1.05; 95% CI 1.03–1.08; P<0.001), heart failure (HR 1.76; 95% CI 1.17–2.66; P=0.007), old myocardial infarction (HR 4.49; 95% CI 2.59–7.81; P<0.001), non-ischemic cardiomyopathy (HR 2.56; 95% CI 1.47–4.46; P=0.001), left atrial diameter (HR 1.22 per 5-mm increase; 95% CI, 1.06–1.41; P=0.006) and recurrence of AF (HR 1.69; 95% CI 1.17–2.44; P=0.005) were independently associated with the incidence of MACCE after catheter ablation.

Conclusion

In the Japanese multicenter cohort of AF ablation, late recurrence of AF was independently associated with increased MACCE, suggesting the significance of sinus rhythm maintenance by catheter ablation.

Kaplan-Meier curves for MACCE

Funding Acknowledgement

Type of funding source: None

Efficacy of cardiac rehabilitation with motion assistance from wearable cyborg hybrid assistive limb in patients with chronic heart failure: a randomized controlled trial

Background

Recent Cochrane Systematic Review suggested that the participation in cardiac rehabilitation is associated with approximately 20% lower cardiovascular mortality and morbidity. Exercise therapy is the key component of cardiac rehabilitation programs. In recent years, innovative technologies have been introduced into the field of rehabilitation, and a typical example is the wearable cyborg Hybrid Assistive Limb (HAL). The wearable cyborg HAL provides motion assistance based on detection of bioelectrical signals on the skin surface when muscle forces are generated. The lumbar-type HAL is expected to expand the therapeutic options for severe cardiac patients who have difficulty in performing usual cardiac rehabilitation programs, such as bicycle pedaling or walking.

Purpose

We aim to compare the efficacy of exercise therapy performed with motion assistance from a lumbar-type HAL versus conventional training (sit-to-stand exercise without HAL) in patients with chronic heart failure.

Methods

This clinical trial is a randomized, non-blinded, and controlled study. Twenty-eight heart failure patients (73.1±13.8 years) who have difficulty in walking at the usual walking speed of healthy subjects were randomly assigned to 2 groups (HAL group or control group) with a 1:1 allocation ratio and performed sit-to stand exercise either with HAL or without HAL for 5 to 30 minutes once a day, and 6 to 10 days during the study period. The brain natriuretic peptide (BNP), isometric knee extensor strength, standing ability (30-seconds chair-stand test: CS-30), short physical performance battery (SPPB) and 6-minute walking distance (6MWD) were measured before and after the completion of cardiac rehabilitation. Cardiac events such as death, re-hospitalization, myocardial infarction and worsening of angina pectoris and heart failure during 1 year after discharge were evaluated.

Results

There was no significant difference in the number of days of exercise therapy between the two groups. BNP, SPPB and 6MWD were improved in both groups. In the HAL group, the isometric knee extensor strength (0.29±0.11 vs 0.35±0.11 kgf/kg, p=0.003) significantly improved and CS-30 (5.5±5.1 vs 8.2±5.3, p=0.054) tended to improve. However, in the control group, either the isometric knee extensor strength (0.35±0.11 vs 0.36±0.14 kgf/kg, p=0.424) or CS-30 (6.0±4.3 vs 9.2±6.2, p=0.075) did not significantly change. HAL group showed significantly more improvement in the isometric knee extensor strength than control group (p=0.045). Cardiac events occurred in 20% in the HAL group and 43% in the control group.

Conclusion

The improvement in isometric knee extensor strength with the assistance from lumbar-type HAL suggests that exercise therapy using this device may be useful in chronic heart failure patients with flail or sarcopenia, a strong poor prognostic factor in these patients.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): This work was supported in part by a grant-in-aid for Scientific Research from the Ministry of Education, Science, and Culture of Japan (JSPS KAKENHI grant number JP17K09485) and funded by the ImPACT Program of the Council for Science, Technology and Innovation (Cabinet Office, Government of Japan) (grant number 2017-PM05-03-01).

Systematic Evaluation of KCNQ1 variant using ACMG/AMP Guidelines and Risk Stratification in Long QT Syndrome Type 1

Background

Mutation/variant-site specific risk stratification in long-QT syndrome type 1 (LQT1) has been well investigated, but it is still challenging to adopt current enormous genomic information to clinical aspects caused by each mutation/variant. We assessed a novel variant-specific risk stratification in LQT1 patients.

Methods

We classified a pathogenicity of 142 KCNQ1 variants among 927 LQT1 patients (536 probands and 391 family members) based on the American College of Medical Genetics and Genomics (ACMG) and Association for Molecular Pathology (AMP) guidelines and evaluated whether the ACMG/AMP-based classification was associated with arrhythmic risk in LQT1 patients.

Results

Among 142 KCNQ1 variants, 60 (42.3%), 58 (40.8%), and 24 (16.9%) variants were classified into pathogenic (P), likely pathogenic (LP), and variant of unknown significance (VUS), respectively. The ACMG/AMP guideline-based classification was significantly associated with syncopal events (particularly those during exercise) and LQT risk score (Schwartz score) in overall population. On the other hand, arrhythmic risk was completely different between probands and families even in the same variants. The baseline QTc interval and variant location could stratify the risk in family members but not in probands, however, the ACMG/AMP-based KCNQ1 variant classification stratified the risk in LQT1 probands as well as family members. Multivariate analysis showed that proband (HR=2.52; 95% CI: 1.93–3.30; p<0.0001), longer QTc interval (≥500ms) (HR=1.41; 95% CI: 1.11–1.79; p<0.0001), variants at membrane spanning (MS) (vs. those at N/C terminus) (HR=1.40; 95% CI: 1.07–1.85; p=0.02), C-loop (vs. N/C terminus) (HR=1.58; 95% CI: 1.11–2.24; p=0.01), and P variants [(vs. LP) (HR=1.71; 95% CI: 1.33–2.23; p<0.0001), (vs. VUS) (HR=1.96; 95% CI: 1.19–3.46; p=0.007)] were significantly associated with syncopal events. A clinical score (0–4) based on the proband, QTc (≥500ms), variant location (MS or C-loop) and P variant by the ACMG/AMP guidelines allowed identification of patients more likely to have arrhythmic events (Figure A and B).

Conclusion

Comprehensive evaluation of clinical findings and pathogenicity of KCNQ1 variants based on the ACMG/AMP-based evaluation may stratify arrhythmic risk of congenital long-QT syndrome type 1.

Figure 1

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): Health Science Research Grant from the Ministry of Health,Labor and Welfare of Japan for Clinical Research on Measures for Intractable Diseases (H24-033, H26-040, H27-032) and a research grant from the Japan Agency for Medical Research and Development (AMED) (15km0305015h0101, 16ek0210073h0001)

Rare SCN10A variants associated with cardiac conduction system diseases

Background

The genetic bases of cardiac conduction-system disease (CCSD) range from ion channelopathies to mutations in many other genes. Genome-wide association studies have shown common variants in SCN10A influence cardiac conduction. However, it has not yet to be determined whether vulnerability to CCSD is associated with rare coding sequence variation in the SCN10A gene.

Purpose

We sought to determine the clinical impact of rare variants in SCN10A in patients with CCSD and classified the variants according to the 2015 American College of Medical Genetics and Genomics (ACMG) standards and guidelines.

Methods

We performed screening for rare variants (minor allele frequency ≤0.001) in SCN10A in CCSD patients with an onset at a young age under 65 or those who had a family history of pacemaker implantation (PMI) (n=40; 18 female; mean age, 41±18 years). We transiently expressed engineered variants in ND 7/23 cells, and conducted whole-cell voltage clamp experiments to clarify the functional properties of the Nav1.8 current.

Results

We identified nine rare variants in SCN10A in 7 patients. Two patients were carriers of two rare variants in SCN10A and 5 were carriers of one rare variant in SCN10A. Four patients were affected with sinus node dysfunction, 1 were atrioventricular block, and 2 were both dysfunctions. We performed electrophysiological study for 8 of 9 rare variants. It demonstrated that 2 rare variants showed gain-of-function, and 3 rare variants showed loss-of-function. We finally determined 5 likely pathogenic variants in SCN10A in 5 patients (12.5%) according to the ACMG standards and guidelines. All 5 patients underwent a pacemaker implantation at an average age of 43±16.

Conclusions

These results demonstrate that SCN10A variants play a pivotal role in enhanced susceptibility of CCSD. We suggest the importance for screening SCN10A variants in clinical settings.

Funding Acknowledgement

Type of funding source: None

B-Type natriuretic peptide predicts major adverse cardiac and cerebrovascular events after catheter ablation of atrial fibrillation: insights from AF frontier ablation registry

Background

High plasma B-Type natriuretic peptide (BNP) level is associated with cardiac events or stroke in patients with atrial fibrillation (AF). However, it is still unknown whether BNP predicts worse clinical outcomes after catheter ablation ofAF.

Purpose

We aimed to see if plasma BNP level is associated with major adverse cardiac and cerebrovascular events (MACCE) after catheter ablation of AF.

Methods

We retrospectively analyzed 1,853 participants (73.1% men, mean age 63.3±10.3 years, 60.7% paroxysmal AF) who received first catheter ablation of AF with pre-ablation plasma BNP level measurement and completed follow-up more than 3 months after the procedure from AF Frontier Ablation Registry, a multicenter cohort study in Japan. We evaluated an association between plasma BNP level before catheter ablation and first MACCE in cox-regression hazard models adjusted for known risk factors. MACCE were defined as stroke/transient ischemic attack (TIA), cardiovascular events or all-cause death.

Results

The mean plasma BNP level was 120.2±3.7 pg/mL. During a mean follow-up period of 21.9 months, 57 patients (3.1%) suffered MACCE (ischemic stroke 8 [14.0%], hemorrhagic stroke 5 [8.8%], TIA 5 [8.8%], hospitalization for heart failure 11 [19.2%], acute coronary syndrome 9 [15.8%], hospitalization for other cardiovascular events 8 [14.0%] and all-cause death 11 [19.2%]). Plasma BNP level of patients with MACCE were significantly higher than those without MACCE (291.7±47.0 vs 114.7±3.42 pg/mL, P<0.001). Multivariate analysis revealed that plasma BNP level (hazard ratio [HR] per 10 pg/mL increase 1.014; 95% confidence interval [CI] 1.005–1.023; P=0.001), baseline age (HR 1.052; 95% CI 1.022–1.084; P=0.001), heart failure (HR 2.698; 95% CI 1.512–4.815; P=0.001), old myocardial infarction (HR 3.593; 95% CI 1.675–7.708; P=0.001) and non-ischemic cardiomyopathy (HR 2.676; 95% CI 1.337 - 5.355; P=0.005) were independently associated with MACCE. At receiver-operating characteristic curve analysis, plasma BNP level before catheter ablation ≥162.7 pg/mL was the best threshold to predict MACCE (area under the curve: 0.71). Kaplan-Meier curve analysis (Figure) showed that the cumulative incidence of MACCE was significantly higher in patients with a BNP ≥162.7 pg/mL than in those with a BNP below 162.7 pg/mL (HR 4.85; 95% CI 2.86–8.21; P<0.001).

Conclusions

Elevation of plasma BNP level was independently related to the increased risk of MACCE after catheter ablation ofAF.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Bristol-Meiers Squibb

Changes of QT interval in the acute phase after pulmonary vein isolation for paroxysmal atrial fibrillation

Introduction

Pulmonary vein isolation (PVI) affects ganglionated plexi (GP) around the atrium, leading to a modification of the intrinsic cardiac autonomic system (ANS). In animal models, GP ablation has a potential risk of QT prolongation and ventricular arrhythmias. However, the impact of PVI on QT intervals in humans remains unclear.

Purpose

This study aims to evaluate the Impact of PVI on QT interval in patients with paroxysmal atrial fibrillation.

Methods

We analyzed consecutive 117 PAF patients for their first PVI procedures. 12-lead ECG was evaluated at baseline, 4 hr, day 1, 1 month, and 3 months after ablation. Only patients with sinus rhythm on 12-lead ECG at each evaluation point without antiarrhythmic drugs were included.

Results

Heart rate significantly increased at 4 hr, day 1, and 1 month. Raw QT interval prolonged at 4 hr (417.1±41.6 ms, P<0.001) but shortened at day 1 (376.4±34.1 ms, P<0.001), 1 month (382.2±31.5 ms, P<0.001), and 3 months (385.1±32.8 ms, P<0.001) compared to baseline (391.6±31.4 ms). Bazett- and Fridericia- corrected QTc intervals significantly prolonged at 4hr (Bazett: 430.8±27.9 ms, P<0.001; Fridericia: 425.8±27.4 ms, P<0.001), day1 (Bazett: 434.8±22.3 ms, P<0.001; Fridericia: 414.1±23.7 ms, P<0.001), 1M (Bazett: 434.8±22.3 ms, P<0.001; Fridericia: 408.2±21.0 ms, P<0.05), and 3M (Bazett: 420.1±21.8 ms, P<0.001; Fridericia: 407.8±21.1 ms, P<0.05) compared to baseline (Bazett: 404.9±25.2 ms; Fridericia: 400.0±22.6 ms). On the other hand, Framingham- and Hodges- corrected QTc interval significantly prolonged only at 4hr (Framingham: 424.1±26.6 ms, P<0.001; Hodges: 426.8±28.4 ms, P<0.001) and at day1 (Framingham: 412.3±29.3 ms, P<0.01; Hodges: 410.6±40.2 ms, P<0.05) compared to baseline (Framingham: 399.2±22.7 ms; Hodges: 400.7±22.8 ms). At 4 hr after ablation, raw QT and QTc of all formulas significantly prolonged than baseline. Raw QT and QTc prolongation at 4hr after ablation were more frequently observed in female patients. Multiple regression analysis revealed that female patient is a significant predictor of raw QT and QTc interval prolongation of all formulas 4hr after PVI.

Conclusions

Raw QT and QTc prolonged after PVI, especially in the acute phase. Female patient is a risk factor for QT prolongation in the acute phase after PVI.

Funding Acknowledgement

Type of funding source: None

L-type amino acid transporter 1, LAT1, in growth hormone-producing pituitary tumor cells

Pituitary tumors (PTs) can cause significant mortality and morbidity due to limited therapeutic options. L-type amino acid transporters (LATs), in particular, the LAT1 isoform, is expressed in a variety of tumor cells. Pharmacological inhibition or genetic ablation of LAT1 can suppress leucine transport into cancer cells, resulting in suppression of cancer cell growth. However, roles of LAT1 in PTs have not been elucidated. Therefore, we assessed LAT1 expression in PTs and evaluated a LAT1-specific inhibitor, JPH203, on rat somatomammotroph tumor cells, GH4 cells. GH4 cells dominantly express LAT1 mRNA rather than other LAT isoforms, whereas LAT2 transcripts were most abundant in normal rat pituitary tissues. JPH203 inhibited leucine uptake and cell growth in GH4 cells in a concentration-dependent manner, and appeared to be independent of the mechanistic target, the rapamycin pathway. Although JPH203 did not induce apoptosis, it suppressed growth hormone production in GH4 cells. Also, genetic downregulation of LAT1 showed similar effects on cell growth and hormone production. These results indicated that restriction of LAT1 substrates by JPH203 modulated both cell growth and hormone production. In conclusion, LAT1 may be a new therapeutic target for PTs because its inhibition leads to suppression of cell growth as well as hormone production. JPH203 may represent a promising drug for clinical use in patients with PTs, with the potential of hormonal control and tumor suppression.

Anaesthesia-dependent oscillatory EEG features in the super-elderly

OBJECTIVE

Although the characteristics of electroencephalograms (EEGs) have been reported to change with age, anaesthesia-dependent oscillatory features and reactivity of the super-elderly EEG to anaesthesia have not been examined in detail.

METHODS

Participants comprised 20 super-elderly patients (age; mean ± standard deviation, 87.1 ± 3.8 years) and 20 young adult patients (35.5 ± 8.5 years). At three levels of sevoflurane anaesthesia (minimum alveolar concentration [MAC] of 0.3, 0.7, and 1.4), oscillatory features of the frontal EEG were examined by analysing quadratic phase coupling (bicoherence) and power spectrum in α and δ-θ areas and compared in an anaesthesia-dependent manner, using the Friedman test.

RESULTS

Among super-elderly individuals, bicoherences in the δ-θ area showed anaesthesia-dependent increases (median [interquartile range], 12.9% [5.2%], 19.2% [9.1%], 23.3% [8.7%]; 0.3, 0.7, 1.4 MAC sevoflurane, p = 0.000), whereas bicoherence in the α area did not change at these different anaesthesia levels (11.2% [3.9%], 12.5% [4.4%], 14.1% [5.7%], respectively; p = 0.142), counter to the results found in young adult patients, where both δ-θ and α bicoherences changed with anaesthesia.

CONCLUSIONS

In the super-elderly, δ-θ bicoherence of EEG shows anaesthesia- dependent changes, whereas α activity remains small irrespective of anaesthesia level.

SIGNIFICANCE

Quantification of δ-θ bicoherence is a candidate for anaesthesia monitoring in the super-elderly.

AB0387 TREATMENT STATUS FOR OSTEOPOROSIS IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS: CROSS-SECTIONAL ANALYSIS FROM A LUPUS REGISTRY OF NATIONWIDE INSTITUTIONS (LUNA)

Background:

Osteoporosis is one of the most important adverse effects of glucocorticoids in patients with systemic lupus erythematosus (SLE). Because osteoporosis is accelerated by chronic kidney disease (CKD), more attention should be paid to the treatment for osteoporosis in SLE patients with CKD. Many treatment options for osteoporosis have emerged recently, but treatment status in patients with SLE is not elucidated.

Objectives:

The purpose of this study is to elucidate the treatment status for osteoporosis in patients with SLE among the CKD stages.

Methods:

Using data from lupus registry of nationwide institutions (LUNA), a cross-sectional analysis was performed. We firstly described treatment status for osteoporosis in all enrolled patients. Secondary, treatment status for osteoporosis was compared among CKD stages. Finally, bone damage in Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI) was compared among CKD stages.

Results:

The median age (interquartile range [IQR]) of enrolled 917 patients was 44 (34- 57) years and 809 patients (88%) were female. CKD stages were follows: CKD stage 1, 234 (26%); CKD stage 2, 465 (51%); CKD stage 3, 189 (21%); CKD stage 4, 9 (1%); CKD stage 5, 16 (2%). Median (IQR) age, female sex, and median (IQR) previous maximum dose of prednisolone in patients with and without CKD (≥CKD stage 3) were 56 (46.5-66) and 41 (32-50), 191 (89%) and 615 (88%), and 40 (30-60) and 40 (30-55) mg/day, respectively. Bisphosphonate was administered in 388 (42%) patients, vitamin D supplements in 448 (49%), Ca supplements in 36 (4%), denosumab in 20 (2%) and teriparatide in 14 (2%), respectively. Of enrolled patients, any treatment for osteoporosis was not administered in 226 (25%) patients. In spite of more frequent bone damage in patients with CKD compared to those without CKD (15% vs 10%, p=0.036), treatment status did not differ between patients with and without CKD (bisphosphonate: 41% vs 46%, p=0.29; vitamin D supplements: 50% vs 44%, p=0.14).

Conclusion:

About a quarter of patients with SLE did not take any treatment for osteoporosis. Treatment for osteoporosis might be strengthened to prevent bone damage in SLE patients with CKD.

Disclosure of Interests:

KEN-EI SADA Speakers bureau: I received speaker’s fee from GSK and Astra Zeneca K.K., Keigo Hayashi: None declared, Yosuke ASANO: None declared, Yu Katayama: None declared, Sumie Hiramatsu Asano: None declared, Keiji Ohashi: None declared, Michiko Morishita: None declared, Haruki Watanabe: None declared, Mariko Narazaki: None declared, Yoshinori Matsumoto: None declared, Nobuyuki Yajima: None declared, Ryusuke Yoshimi: None declared, Yasuhiro Shimojima: None declared, Shigeru Ono: None declared, Hiroshi Kajiyama: None declared, Kunihiro Ichinose: None declared, Shuzo Sato: None declared, Michio Fujiwara: None declared, Jun Wada: None declared

Imaging of lysophosphatidylcholine in an induced pluripotent stem cell-derived endothelial cell network

Introduction

Vascular endothelial cell disorders are closely related to cardiovascular disease (CVD) and pulmonary diseases. Abnormal lipid metabolism in the endothelium leads to changes in cell signalling, and the expression of genes related to immunity and inflammation. It is therefore important to investigate the pathophysiology of vascular endothelial disorders in terms of lipid metabolism, using a disease model of endothelium.

Methods

Human induced pluripotent stem cell-derived endothelial cells (iECs) were cultured on a matrigel to form an iEC network. Lipids in the iEC network were investigated by matrix-assisted laser desorption/ionization (MALDI) time-of-flight (TOF) imaging mass spectrometry (IMS) analysis. Ion fragments obtained by mass spectrometry were analysed using an infusion method, involving precursor ion scanning with fragment ion.

Results

The MALDI TOF IMS analysis revealed co-localized intensity of peaks at m/z 592.1 and 593.1 in the iEC network. Tandem mass spectrometry (MS/MS) analysis by MALDI-imaging, in conjunction with precursor ion scanning using an infusion method with lipid extracts, identified that these precursor ions were lysophosphatidylcholine (LPC) (22:5) and its isotype.

Conclusion

The MALDI-imaging analysis showed that LPC (22:5) was abundant in an iEC network. As an in vitro test model for disease and potential therapy, present analysis methods using MALDI-imaging combined with, for example, mesenchymal stem cells (MSC) to a disease derived iEC network may be useful in revealing the changes in the amount and distribution of lipids under various stimuli.

Development of an organ bath technique for isolated rat pancreas preparations to assess the effect of 1,5-AG on insulin secretion

To investigate substances related to insulin secretion, we reported a convenient experimental method to reproduce insulin secretion from isolated rat pancreas preparations using an organ bath. While the method has experimental utility for investigating insulin secretion, optimization of the experimental design is still needed. The level of insulin outflow in the control decreased over time in our previous study. Decreasing serum 1,5-anhydroglucitol (1,5-AG) levels is also known to be shown in patients with worsening glycemic control. There is one in vitro report demonstrated that 1,5-AG induced insulin release. It appears that discussion needs to be deepened further on it. In this study, we investigated the effect of 1,5-AG on insulin secretion through to optimize the condition of endocrine function using the ex vivo organ bath technique. The level of insulin outflow in the control and 1,5-AG groups decreased over time in the organ bath experiment. To analyze the effect of trypsin on reduced insulin secretion, pancreas preparation was treated with soybean trypsin inhibitor (TI). Insulin outflow levels of the TI group were significantly higher than the control group. An enzyme indicator of tissue damage tended to be lower in the TI group. There was no significant enhancement of insulin secretion by 1,5-AG. The present study demonstrated the utility of TI application for the organ bath technique. This finding supported the development of an organ bath technique for the assessment of the effects of novel therapeutics on insulin secretion.

Predictive immunohistochemical features for tumour response to chemoradiotherapy in rectal cancer

Background

Reduced expression of cluster of differentiation (CD) 133 and cyclo‐oxygenase (COX) 2, and increased density of CD8+ tumour‐infiltrating lymphocytes, are associated with a favourable tumour response to preoperative chemoradiotherapy (CRT). This study aimed to evaluate these markers in relation to tumour response after preoperative CRT in two rectal cancer cohorts.

Methods

Patients with low rectal cancer who underwent radical resection and preoperative short‐term CRT in 2001–2007 (retrospective cohort) and long‐term CRT in 2011–2017 (prospective cohort) were analysed. Pretreatment biopsies were stained immunohistochemically using antibodies to determine CD133 and COX‐2 expression, and increased CD8+ density. Outcome measures were tumour regression grade (TRG), tumour downstaging and survival.

Results

For 95 patients in the retrospective cohort, the incidence of TRG 3–4 was 67 per cent when two or three immunohistochemistry (IHC) features were present, but only 20 per cent when there were fewer features (P < 0·001). The incidence of tumour downstaging was higher in patients with at least two IHC features (43 versus 22 per cent with fewer features; P = 0·029). The 49 patients in the prospective cohort had similar rates to those in the retrospective cohort (TRG 3–4: 76 per cent for two or more IHC features versus 25 per cent with fewer features, P < 0·001; tumour downstaging: 57 versus 25 per cent respectively, P = 0·022). Local recurrence‐free survival rates in patients with more or fewer IHC features were similar in the retrospective and prospective cohort (P = 0·058 and P = 0·387 respectively).

Conclusion

Assessment of CD133, COX‐2 and CD8 could be useful in predicting a good response to preoperative CRT in patients with lower rectal cancer undergoing neoadjuvant therapy. Further studies are needed to validate the results in larger cohorts and investigate a survival benefit.

Damage accrual related to pregnancies before and after diagnosis of systemic lupus erythematosus: a cross-sectional and nested case-control analysis from a lupus registry

OBJECTIVE

The objective of this study was to evaluate the chronic damage associated with pregnancies before and after the diagnosis of systemic lupus erythematosus (SLE).

METHODS

Using childbearing-aged female SLE patient data registered at the Okayama and Showa University Hospitals, a nested case-control analysis was performed to investigate the relationship between pregnancy and chronic damage using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SDI).

RESULTS

Pregnancy occurred in 22 patients before and 13 patients after the diagnosis of SLE in 104 eligible patients. Live births occurred in 82% (33/40) and 50% (9/18) of the pregnancies before and after the diagnosis of SLE, respectively. After matching age and disease duration, 33 case patients with chronic damage (SDI ≥ 1) and 33 control patients without chronic damage (SDI = 0) were selected. Hypertension was more frequent in cases than in controls (48% vs. 24%, p = 0.041). Pregnancies before and after the diagnosis of SLE were comparable between cases and controls (before the diagnosis: nine case patients and eight control patients; after the diagnosis: three case patients and five control patients; p = 1.00). Even after adjusting for hypertension using multivariate analysis, the pregnancies before and after the diagnosis were not significant predictors for chronic damage (odds ratio = 1.48 (95% confidence interval 0.33-6.65)), p = 0.60 of the pregnancy before the diagnosis; odds ratio = 0.78 (95% confidence interval 0.13-4.74), p = 0.78 of the pregnancy after the diagnosis).

CONCLUSION

Pregnancies, either before or after the diagnosis of SLE, did not show any differences in chronic damage. Our results help alleviate fears regarding childbearing in female patients with SLE and their families.

Tissue-dependent DNA methylation of carp uncoupling protein 1 promoter

DNA methylation of enhancers and promoters generally inhibits gene transcription. DNA methylation occurs predominantly at the dinucleotide CpG, a methyl group that is covalently bonded to cytosine. We have previously demonstrated tissue-restricted expression of the uncoupling protein 1 (Ucp1) in common carp. Here, we characterized the methylation status of the upstream region of the transcriptional initiation site of the carp Ucp1 gene in the liver, brain, kidney, skeletal muscle, and scales. In addition, we explored the direct role of methylation on Ucp1 transcription. Ucp1 expression was higher in the liver than that in other tissues including the kidney, skeletal muscle, and scales. The extent of methylation at nt -2178 and nt -2103 was lower in the liver and kidney than that in the brain, skeletal muscle, and scales. In addition, methylation at the upstream proximal-region of the Ucp1 gene was generally less frequent in the liver compared with that in the other organs. The transcriptional activation assay using the CpG-free luciferase-based reporter suggested that the methylation of the distal and proximal regions of the carp Ucp1 gene did not affect Ucp1 transcription. Unexpectedly, mutation of cytidylic acid to guanylic acid at nt -108 decreased Ucp1 promoter activity. The present results reveal that the status of DNA methylation of the upstream region of the carp Ucp1 gene is different among different tissues, but suggest that the DNA methylation do not directly repress the transcription of Ucp1.

Usefulness of real-time elastography for diagnosing lymph node metastasis of skin cancer: does elastography potentially eliminate the need for sentinel lymph node biopsy in squamous cell carcinoma?

BACKGROUND

The metastatic involvement of regional lymph nodes is the most important prognostic factor for overall survival of skin cancer patients. The sonographic technique of freehand real-time tissue elastography (RTE), which displays tissue rigidity as a colour overlay of the tissue image, was developed.

OBJECTIVE

Our purpose was to evaluate the benefit of RTE for detecting lymph node metastases of skin cancer non-invasively before operation.

METHODS

We first selected lymph nodes of skin cancer patients which had already been diagnosed by biopsy as being reactive or metastatic, and then retrospectively collected images of RTE and B-mode and colour Doppler ultrasound on those lymph nodes performed preoperatively. Twenty-one lymph nodes from 12 patients with squamous cell carcinoma (SCC), 23 lymph nodes from 14 patients with malignant melanoma (MM) and 14 lymph nodes from six patients with extramammary Paget disease (Paget) were investigated. Elastographic images were assessed on a scale of one to four according to the percentage of high elasticity (hard) area (HEA) in the lymph node.

RESULTS

In all three skin cancers, lymph nodes evaluated as grade 3 or 4 by RTE were metastatic. All lymph nodes evaluated as grade 1 or 2 by RTE were reactive in SCC, whereas some lymph nodes evaluated as grade 1 or 2 were metastatic in MM and Paget.

CONCLUSION

Real-time tissue elastography may aid in distinguishing reactive lymph nodes from metastatic ones especially in SCC.

P3755Left atrial enlargement as an independent risk factor for ischemic stroke in Japanese atrial fibrillation patients: pooled analysis of five major Japanese atrial fibrillation registries

Background

Atrial fibrillation (AF) increases the risk of ischemic stroke. It remains unknown whether left atrial diameter determined by routine trans-thoracic echocardiography is a risk factor for ischemic stroke in non-valvular AF (NVAF) patients.

Purpose

The aim of this study is to investigate the impact of left atrial enlargement (LAE) on the incidence of ischemic stroke in a large-scale cohort of Japanese NVAF patients.

Methods

We combined the data of 5 major AF registries in Japan, J-RHYTHM Registry, Fushimi AF Registry, Shinken Database, Keio interhospital Cardiovascular Studies, and Hokuriku AF Registry. After excluding patients without echocardiographic data, 7,672 NVAF patients were analyzed in the present study (mean age, 69.3±12.3 years; mean CHADS2 score, 1.6±1.3). We compared clinical characteristics and the incidence of ischemic stroke between NVAF patients with LAE (left atrial diameter >45 mm; LAE group) and those without (non-LAE group).

Results

The mean left atrial diameter was 43.1±8.6 mm, and the LAE group accounted for 40.0% (n=3,066) of the entire cohort. Compared with non-LAE group (60.0%, n=4,606), the LAE group was older (LAE vs. non-LAE; 70.3±12.0 vs. 68.0±12.5, p<0.01), more often non-paroxysmal type (73.7% vs. 32.1%, p<0.01), had higher CHADS2 (1.86±1.34 vs. 1.46±1.29, p<0.01) and CHA2DS2-VASc (3.02±1.83 vs. 2.53±1.78, p<0.01) scores, and more frequently received oral anticoagulant (72.9% vs. 55.0%, p<0.01).

During the median follow-up period of 774.5 days (interquartile range: 567–1466 days), ischemic stroke occurred in 241 patients (131 vs. 110 patients; 1.52 vs. 0.82 per 100 person-years). In Kaplan Meier analysis, LAE was associated with a higher incidence of ischemic stroke (unadjusted hazard ratio (HR): 1.83, 95% confidence interval (CI): 1.42–2.36; log rank p<0.01) (Figure). LAE was independently associated with increased risk of ischemic stroke (adjusted HR: 1.63, 95% CI: 1.25–2.11; p<0.01) after adjustment by the components of CHADS2 score and the use of oral anticoagulant, on multivariate Cox proportional hazard analysis.

Conclusion

In this large-scale cohort of Japanese patients with AF, LAE was an independent predictor of ischemic stroke, suggesting that this simple echocardiographic parameter could refine thromboembolic risk stratification of NVAF patients.

Acknowledgement/Funding

Japan Agency for Medical Research and Development, AMED