Exosomes from Von Hippel-Lindau-Null Cancer Cells Promote Metastasis in Renal Cell Carcinoma

Exosomes are extracellular vesicles that modulate essential physiological and pathological signals. Communication between cancer cells that express the von Hippel-Lindau (VHL) tumor suppressor gene and those that do not is instrumental to distant metastasis in renal cell carcinoma (RCC). In a novel metastasis model, VHL(-) cancer cells are the metastatic driver, while VHL(+) cells receive metastatic signals from VHL(-) cells and undergo aggressive transformation. This study investigates whether exosomes could be mediating metastatic crosstalk. Exosomes isolated from paired VHL(+) and VHL(-) cancer cell lines were assessed for physical, biochemical, and biological characteristics. Compared to the VHL(+) cells, VHL(-) cells produce significantly more exosomes that augment epithelial-to-mesenchymal transition (EMT) and migration of VHL(+) cells. Using a Cre-loxP exosome reporter system, the fluorescent color conversion and migration were correlated with dose-dependent delivery of VHL(-) exosomes. VHL(-) exosomes even induced a complete cascade of distant metastasis when added to VHL(+) tumor xenografts in a duck chorioallantoic membrane (dCAM) model, while VHL(+) exosomes did not. Therefore, this study supports that exosomes from VHL(-) cells could mediate critical cell-to-cell crosstalk to promote metastasis in RCC.

Degradation of three β-O-4 lignin model compounds via organic electrolysis and elucidation of the degradation mechanisms

Woody biomass comprising cellulose, hemicellulose, and lignin has been the focus of considerable attention as an alternative energy source to fossil fuel for various applications. However, lignin has a complex structure, which is difficult to degrade. Typically, lignin degradation is studied using β-O-4 lignin model compounds as lignin contains a large number of β-O-4 bonds. In this study, we investigated the degradation of the following lignin model compounds via organic electrolysis: 2-(2-methoxyphenoxy)-1-(4-methoxyphenyl)ethanol 1a, 1-(3,4-dimethoxyphenyl)-2-(2-methoxyphenoxy)-1,3-propanediol 2a, and 1-(4-hydroxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)-1,3-propanediol 3a. The electrolysis was conducted for 2.5 h at a constant current of 0.2 A using a carbon electrode. Various degradation products such as 1-phenylethane-1,2-diol, vanillin, and guaiacol were identified upon separation via silica-gel column chromatography. The degradation reaction mechanisms were elucidated using electrochemical results as well as density functional theory calculations. The results suggest that the organic electrolytic reaction can be used for the degradation reaction of a lignin model with β-O-4 bonds.

Tumor heterogeneity in VHL drives metastasis in clear cell renal cell carcinoma

Loss of function of the von Hippel-Lindau (VHL) tumor suppressor gene is a hallmark of clear cell renal cell carcinoma (ccRCC). The importance of heterogeneity in the loss of this tumor suppressor has been under reported. To study the impact of intratumoral VHL heterogeneity observed in human ccRCC, we engineered VHL gene deletion in four RCC models, including a new primary tumor cell line derived from an aggressive metastatic case. The VHL gene-deleted (VHL-KO) cells underwent epithelial-to-mesenchymal transition (EMT) and exhibited increased motility but diminished proliferation and tumorigenicity compared to the parental VHL-expressing (VHL+) cells. Renal tumors with either VHL+ or VHL-KO cells alone exhibit minimal metastatic potential. Combined tumors displayed rampant lung metastases, highlighting a novel cooperative metastatic mechanism. The poorly proliferative VHL-KO cells stimulated the proliferation, EMT, and motility of neighboring VHL+ cells. Periostin (POSTN), a soluble protein overexpressed and secreted by VHL non-expressing (VHL-) cells, promoted metastasis by enhancing the motility of VHL-WT cells and facilitating tumor cell vascular escape. Genetic deletion or antibody blockade of POSTN dramatically suppressed lung metastases in our preclinical models. This work supports a new strategy to halt the progression of ccRCC by disrupting the critical metastatic crosstalk between heterogeneous cell populations within a tumor.

Abstract 1611: Statins inhibit the collaborative metastasis mediated by VHL heterogeneity in clear cell renal cell carcinoma (ccRCC) via a non-cholesterol pathway

BACKGROUND: Despite the advancement of targeted therapies and immunotherapies, the outcome of clear cell renal cell carcinoma (ccRCC) remains poor at the metastatic stage, with a median survival of mere 7 months. This devastating outcome is partially due to an inadequate understanding of the metastatic mechanism of ccRCC. Previously, we found that two distinct cell populations co-exist in the malignancy: one with the functional von-Hippel Lindau (VHL) gene (VHL(+)) and the other without (VHL(-)). This heterogeneity in VHL plays an essential role, where the VHL(-) cells serve as the metastatic driver and promote VHL(+) cells to disseminate to distant organs such as the lungs. In this study, we sought to find small molecules that can selectively inhibit the VHL(-) cells' growth and survival. We hypothesize that these molecules will effectively inhibit ccRCC metastases by targeting the metastatic driver population.

METHODS: CRISPR knockout was conducted to generate VHL(-) cells from a murine RCC cell line, RENCA. Both VHL(-) and (+) cells were then fluorescently labeled and went through high-throughput screening (HTS) with 2,530 FDA-approved drugs. We followed a ratiometric black-box approach to identify selective modulators of cell growth and survival of VHL(-) cells without affecting VHL(+) counterparts. CRISPR knockin was conducted on human ccRCC cells, as well, generating VHL(+) and (-) pairs of 786O, RCC4, and a patient-derived primary cell line.

RESULTS: HTS yielded 9 hits that selectively inhibited the survival of the metastatic drivers VHL(-) cells. 4 out of 9 hits belonged to the same drug family called statins. Statins bind to HMG-CoA reductase (HMGCR) and help lower cholesterol, thus are widely prescribed to high-risk patients for cardiovascular diseases. Interestingly, not all statins showed the VHL(-) suppressing effect, resulting in IC50 varying from 0.6uM to >50mM. Atorvastatin and rosuvastatin, the two most potent and prescribed statins for cholesterol-lowering with the highest HMGCR affinity, did not show as much efficacy as other statins. This observation also held true in human ccRCC cell lines, suggesting an involvement of a non-cholesterol/HMGCR pathway in statins’ inhibitory effect on VHL(-) cells. Animal studies were conducted using fluvastatin, which had the lowest IC50 in our model. Intraperitoneal injection of 15mg/kg fluvastatin Q.O.D for 2 weeks successfully suppressed the growth of primary tumors, especially by eliminating VHL(-) cells, and most importantly, prevented lung metastases in the treatment group, whereas all of the control group developed metastases.

CONCLUSIONS: Translational potential of this project is enormous. By investigating the mechanism of action further, we could potentially reposition the FDA-approved, cheap, and widely available small molecules as a novel anti-metastatic therapeutic in ccRCC.

Citation Format: Moe Ishihara, Junhui Hu, Celine Cano-Ruiz, Maia Jackson, Aimee Wu, Stuart Conway, Robert D. Damoiseaux, Lily Wu. Statins inhibit the collaborative metastasis mediated by VHL heterogeneity in clear cell renal cell carcinoma (ccRCC) via a non-cholesterol pathway [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1611.

Sodium-glucose cotransporter 2 inhibitors not only suppress recurrence after atrial fibrillation ablation but also cause atrial reverse remodeling

Background

Sodium-glucose cotransporter 2 (SGLT2) inhibitors have shown fewer heart failure (HF) hospitalization and cardiovascular death in patients with type-2 diabetes mellitus (DM). Atrial fibrillation (AF) is associated with both HF and DM, and we reported SGLT2 suppressed AF recurrence after catheter ablation (CA) than dipeptidyl peptidase-4 (DPP4) inhibitor.

Purpose

We evaluated whether SGLT2 itself induces atrial reverse remodeling.

Methods

This is a sub-analysis of a prospective randomized controlled open-label clinical study for comparing the suppressive effect of SGLT2 inhibitor with DPP4 inhibitor on AF recurrence after CA. Eighty AF patients with type-2 DM were randomized to Tofogliflozin group or Anagliptin group with a computer-generated random sequence, which was stratified by left atrial diameter and AF type at screening. Primary outcome is AF recurrence at 12 months after CA, and secondary outcomes include the echocardiographic findings.

Results

70 patients (70.3±8.1 years, 58 male, 30 paroxysmal AF, 38 Tofogliflozin) were analyzed. Recurrent AF was detected in 24 patients (34.3%), and the AF recurrence ratio was higher in the Anagliptin group than the Tofogliflozin group. In 46 patients without AF recurrence (17 Anagliptin, 29 Tofogliflozin), LAVI has shrunk in 12 months compared to the baseline (42.8±11.9 to 36.6±11.2ml/m2) and the reduction of LAVI was larger in Tofogliflozin group than Anagliptin group (−8.6±2.0ml/m2 vs. −2.0±2.6ml/m2, P=0.0471).

Conclusion

Tofogliflozin not only suppressed AF recurrence after CA but also caused atrial reverse remodeling than Anagliptin in type-2 DM patients.

Funding Acknowledgement

Type of funding sources: None.

Tankyrase Regulates Neurite Outgrowth through Poly(ADP-ribosyl)ation-Dependent Activation of β-Catenin Signaling

Poly(ADP-ribosyl)ation is a post-translational modification of proteins by transferring poly(ADP-ribose) (PAR) to acceptor proteins by the action of poly(ADP-ribose) polymerase (PARP). Two tankyrase (TNKS) isoforms, TNK1 and TNK2 (TNKS1/2), are ubiquitously expressed in mammalian cells and participate in diverse cellular functions, including wnt/β-catenin signaling, telomere maintenance, glucose metabolism and mitosis regulation. For wnt/β-catenin signaling, TNKS1/2 catalyze poly(ADP-ribosyl)ation of Axin, a key component of the β-catenin degradation complex, which allows Axin’s ubiquitination and subsequent degradation, thereby activating β-catenin signaling. In the present study, we focused on the functions of TNKS1/2 in neuronal development. In primary hippocampal neurons, TNKS1/2 were detected in the soma and neurites, where they co-localized with PAR signals. Treatment with XAV939, a selective TNKS1/2 inhibitor, suppressed neurite outgrowth and synapse formation. In addition, XAV939 also suppressed norepinephrine uptake in PC12 cells, a rat pheochromocytoma cell line. These effects likely resulted from the inhibition of β-catenin signaling through the stabilization of Axin, which suggests TNKS1/2 enhance Axin degradation by modifying its poly(ADP-ribosyl)ation, thereby stabilizing wnt/β-catenin signaling and, in turn, promoting neurite outgrowth and synapse formation.

Thromboembolic risk of movable type left atrial appendage thrombi in patients with atrial fibrillation under widespread use of anticoagulants

Background

Left atrial appendage thrombi (LAAT), especially movable type LAAT, have been reported to be high-risk for thromboembolic events in patients with atrial fibrillation (AF). However, thromboembolic risk of the movable-type LAAT under widespread use of anticoagulant therapy remains unclear.

Methods

We retrospectively studied 65 LAAT patients taking anticoagulants out of 1381 consecutive patients who underwent transthoracic echocardiography prior to cardioversion or catheter ablation for AF. Patients with significant valvular disease and coagulation disorder were excluded. Clinical data were evaluated at the time of TEE. The LAAT were classified into movable and fixed type LAAT by three independent observers.

Results

Sixteen of 65 LAAT patients showed movable type LAAT. During follow-up (42±34 months), one patient underwent emergency thrombectomy, 5 patients developed thromboembolic event, and 12 patients died. There were no differences in clinical data, parameters, thrombectomy/thromboembolic event, and survival rate between patients with movable and fixed type LAAT.

Conclusion

Thromboembolic risk of the movable-type LAAT is the same as fixed type LAAT, under widespread use of anticoagulant therapy.

Funding Acknowledgement

Type of funding sources: None.

The impact of abnormal conduction zone on outcomes after catheter ablation for atrial fibrillation

Background

The abnormal conduction zone (ACZ) in the left atrium (LA) has attracted attention as an arrhythmia substrate in atrial fibrillation (AF).

Purpose

We investigated whether the ACZ affects outcomes after catheter ablation (CA) for AF.

Methods

We studied 78 patients (42 Non-paroxysmal AF, 49 males, and 68±10 years) who received CA for AF. High-density LA mapping during high right atrial pacing was constructed gaining than 2000 points (average 4377±846 points). Isochronal activation maps created at 5-ms interval setting. ACZ was identified by locating a site with isochronal crowding of ≥3 isochrones, and ≥8 isochrones were defined as the conduction block zone (CBZ) in a 4-mm diameter tag (conduction velocity were calculated as ≤27 cm/s and≤10 cm/s, respectively).

Result

Recurrent AF was detected in 25/78 patients (32%) during the follow-up period (9.2±3.0 month). ACZ and CBZ were distributed linearly, and ACZ was observed in 73 of 78 patients and 8 of these 73 patients had the CBZ. Univariate analysis revealed that elevated body mass index (26.2±3.8 vs. 24.3±3.3 kg/m2, P=0.0303), the higher prevalence of non-paroxysmal AF (72% vs. 45%, P=0.0272), larger LA diameter (47.6±6.6 vs. 42.1±6.9 mm, P=0.0014), and longer length of ACZ (79.7±45.1 vs. 52.9±35.7 mm, P=0.0058) were associated with recurrent AF after CA. On multivariate analysis, longer ACZ was independently associated with recurrent AF. Moreover, patients with longer ACZ (cutoff value: 84 mm) had a higher risk of recurrent AF than shorter ACZ (12/22; 55% vs 13/56; 23%, log-rank P=0.0024).

Conclusion

The length of ACZ was associated with recurrent AF after CA.

Funding Acknowledgement

Type of funding sources: None.

The impact of oral direct thrombin inhibitors on activated clotting time during catheter ablation in patients with atrial fibrillation

Funding Acknowledgements

Type of funding sources: None.

Background

Direct thrombin inhibitors (DTIs) unlike factor Xa-inhibitors (Xa-inhibitors) is associated with fewer bleeding complications than warfarin in patients who had catheter ablation (CA) for atrial fibrillation (AF). However, the mechanisms remains unclear, and activated clotting time (ACT) is used to control heparin-dose for thromboembolic prevention during CA. Methods: We retrospectively studied 543 patients taking direct oral anticoagulant (DOAC) who underwent CA for AF (375 males, age 67 ± 10, 251 non-paroxysmal AF, 142 DTIs). Patients with off-label usage of DOAC were excluded. ACT was measured before (Pre-ACT) and after (post-ACT) initial heparin administration (3000U + 100U/kg), and total heparin-dose was evaluated. Results: Pre-ACT and post-ACT were extended in patients with DTIs (150 ± 21 vs 123 ± 15; P < 0.0001 and 322 ± 39 vs 309 ± 42 sec; P = 0.0013). Patients with Xa-inhibitors required higher total heparin-dose (199 ± 43 vs 175 ± 34 U/kg; P < 0.0001). During and after CA, none had thromboembolic events and 14 patients (3 DTIs, 11 Xa-inhibitor) showed bleeding events (Figure). Conclusions: ACT is extended in patients taking DTIs. Xa-inhibitors might have anticoagulant effects which are not reflected in ACT. Abstract Figure.

Impact of lipoprotein(a) levels on angiographic severity of femoropopliteal lesions

Background

High lipoprotein(a) [Lp(a)] levels are a risk factor for peripheral artery disease (PAD). However, the association between Lp(a) levels and angiographic severity of PAD has not been systematically studied.

Purpose

The aim of this study was to assess the impact of Lp(a) levels on angiographic severity of femoropopliteal lesions in patients with PAD.

Methods

We retrospectively analyzed a single-center database including 108 patients (74±8 years, 69% male) who underwent endovascular therapy for de novo femoropopliteal lesions and measured Lp(a) levels before therapy between June 2016 and September 2019. Patients were divided into low Lp(a) [LP(a) <30 mg/dL; 77 patients] and high Lp(a) [LP(a) ≥30 mg/dL; 31 patients] groups. Trans-Atlantic Inter-Society Consensus (TASC) II classification, calcification [referring to peripheral arterial calcium scoring system (PACSS) classification] and lesion length were compared between the groups.

Results

Median Lp(a) was 16 (7–31) mg/dL.The prevalence of TASC II class D (13% vs 38%, P<0.01) and severe calcification (PACSS 4) (6% vs 23%, P=0.02) was significantly higher and lesion length was longer (123±88 mm vs 175±102 mm, P<0.01) in the high Lp(a) group than in the low Lp(a) group.(Table and Figure) In multivariate analysis, Lp(a)≥30 was an independent predictor for TASC II class D (HR=3.67, P=0.02) and PACSS 4 (HR=4.97, P=0.02) prevalence.

Conclusion

Lp(a) was associated with angiographic severity of femoropopliteal lesions in patients with PAD.

Comparison of angiographic severity

Funding Acknowledgement

Type of funding source: None

Increased left ventricular stiffness assessed by diastolic wall strain causes symptoms in patients with premature ventricular contraction

Background

Premature ventricular contraction (PVC) is one of common arrhythmias and only some patients complain of PVC-related symptoms, however the mechanisms which cause the symptoms remain unclear in patients with PVCs.

Purpose

We investigated whether the left ventricular (LV) stiffness assessed by diastolic wall strain (DWS) relate symptoms or not in patients with PVC.

Methods

We studied 109 patients (48 males, age 60±19) with frequent monomorphic PVCs who underwent 12-leads electrocardiogram (ECG), signal-averaged electrocardiogram (SAECG), 24h-Holter ECG recording, and transthoracic echocardiography (TTE). Patients with structural heart disease or other arrhythmias such as atrial fibrillation were excluded. Clinical factors, blood samples for atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP), and filtered QRS duration (f-QRS) and root mean square voltage of the terminal 40ms of the QRS complex (RMS40) obtained by SAECG were evaluated. We assessed PVC-SV (stroke volume during PVC), PVC-CI (CI between the previous sinus beat and VPC), and left ventricular (LV) stiffness assessed by diastolic wall strain (DWS). DWS was calculated from the M-mode echocardiographic measurement of the LV posterior wall thickness at end-systole (PWs) and end-diastole (PWd) during sinus rhythm, and DWS was defined as (PWs − PWd)/PWs.

Results

31patients (28%) had PVC-related symptoms (18 palpitation and 13 pulse deficit). Patients with PVC-related symptoms showed shorter PVC coupling interval index (52±10 vs. 58±11%, p=0.0140), reduced PVC-SV (21±12 vs. 29±17ml, p=0.0103) and decreased DWS (0.38±0.06 vs. 0.42±0.06, p=0.0011). Meanwhile, the level of BNP and ANP, f-QRS, RMS40, QRS morphology of PVC and the total number of PVC per day were not associated with PVC-related symptoms. On multivariate analysis, decreased DWS was only independently associated with PVC-related symptoms (p=0.0357, OR 2.3629 for each 0.1 decrease in DWS 95% CI 1.0583–5.5815).

Conclusion

The reduced diastolic wall strain relates with PVC-related symptoms. The increased left ventricular stiffness might cause symptoms in patients with PVC.

Funding Acknowledgement

Type of funding source: None

Left ventricular stiffness assessed by diastolic wall strain predicts asymptomatic atrial high rate episodes in patients with pacemaker implantation

Background

Asymptomatic atrial fibrillation has been reported to be associated with an increased risk of embolism.

Purpose

We investigated whether the left ventricular (LV) stiffness assessed by diastolic wall strain (DWS) predicts atrial high rate episodes (AHREs) in patients with pacemaker implantation (PMI).

Methods

One hundred forty seven patients (76 males, 75.2±8.9 years, 62 with sick sinus syndrome; SSS and 85 with atrioventricular block) who did not show atrial tachyarrhythmia before PMI were studied. DWS and other measurements were assessed using transthoracic echocardiography before DDD-pacemaker implantation. DWS was calculated from the M-mode echocardiographic measurement of the LV posterior wall thickness at end-systole (PWs) and end-diastole (PWd), and DWS was defined as (PWs-PWd)/PWs.

Results

AHREs (>5 min and >180 beats/min) were detected in 50/147 patients during follow-up periods (38.3±13.8 months). Patients with AHREs showed reduced DWS (0.29±0.07 vs. 0.39±0.06, p<0.0001), larger left atrial volume index, elevated E/e' ratio, thicker LV PWd, higher prevalence of SSS, and left bundle branch block pattern during ventricular pacing. On multivariate analysis, DWS was only independently associated with AHREs (p<0.0001, HR 1.987 for each 0.1 decrease in DWS, 95% CI 1.553–2.650). Patients with reduced DWS (<0.33) had a higher risk of incidences of AHREs (Figure 1).

Conclusions

LV stiffness assessed by DWS predicts AHREs in patients with PMI.

Figure 1

Funding Acknowledgement

Type of funding source: None

Slow conduction zone as an early electrical remodeling change in patients with atrial fibrillation

Background

The slow conduction zone (SCZ) in the left atrium (LA) detected using 3-D mapping and high-resolution imaging system has attracted attention as an arrhythmia substrate of atrial fibrillation (AF). However, the occurrence mechanism of SCZ remains unclear.

Purpose

This aim of this study is to clarify whether SCZ is related to the low voltage zone (LVZ) or the LA anatomical contact areas with other organs such as aorta or thoracic spine in patients with AF.

Methods

We studied 36 patients (21 males, 68±10 years, 14 paroxysmal AF; PAF, 17 persistent AF; PeAF, 5 long-standing persistent AF; LS-PeAF) who received catheter ablation for AF. High-density LA mapping during sinus rhythm or right atrial pacing after pulmonary vein isolation were constructed by acquiring more than 2000 endocardial points in each patient. Isochronal activation maps were created at 5-ms interval setting, and the SCZ was identified on the activation map by finding a site with isochronal crowding of ≥3 isochrones, which are calculated as ≤27 cm/s (figure). The LVZ was defined as the following; mild (<1.5 mV), moderate (<1.0 mV), and severe LA-LVZ (<0.5 mV). The LA contact areas (CoAs; ascending aorta-anterior LA, descending aorta-posterior LA, and vertebrae-posterior LA) were assessed using computed tomography.

Results

The SCZ was distributed linearly (figure), and observed in 35 of 36 patients (97.2%). The SCZ was often found in the anterior (89%), roof (64%), and septal wall (47%) of LA, and longest in patients with LS-PeAF (PAF: 56±34 mm, PeAF; 79±41 mm, LS-PeAF; 107±34mm, P=0.0351). The prevalence rate of SCZ (97.2%) was higher than LVZ (figure, mild LA-LVZ; 91.7%, moderate LA-LVZ: 66.7%, severe LA-LVZ; 25%). The 55.8% of SCZ overlapped with mild LA-LVZ, 37.6% of SCZ with moderate LA-LVZ, and 19.1% of SCZ with severe LA-LVZ. The LA CoAs were found in all patients. A total of 72 CoAs (average surface area, 7.0±4.0 cm2) were identified. A CoA was found in each of the three representative regions, ascending aorta-anterior LA (4.1±2.0 cm2, 36 of 36 patients, 100%), descending aorta-posterior LA (2.3±1.2 cm2, 12 of 36 patients, 33%), and vertebrae-posterior LA (3.4±2.1 cm2, 24 of 36 patients, 67%). However, only 22% of SCZ matched with the LA anatomical contact areas.

Conclusion

The slow conduction zone reflects LA electrical remodeling and may be a precursor finding of the low voltage zone, not LA contact areas in patients with atrial fibrillation.

Funding Acknowledgement

Type of funding source: None

Comparing Metastatic Clear Cell Renal Cell Carcinoma Model Established in Mouse Kidney and on Chicken Chorioallantoic Membrane

Metastatic clear cell renal cell carcinoma (ccRCC) is the most common subtype of kidney cancer. Localized ccRCC has a favorable surgical outcome. However, one third of ccRCC patients will develop metastases to the lung, which is related to a very poor outcome for patients. Unfortunately, no therapy is available for this deadly stage, because the molecular mechanism of metastasis remains unknown. It has been known for 25 years that the loss of function of the von Hippel-Lindau (VHL) tumor suppressor gene is pathognomonic of ccRCC. However, no clinically relevant transgenic mouse model of ccRCC has been generated. The purpose of this protocol is to introduce and compare two newly established animal models for metastatic ccRCC. The first is renal implantation in the mouse model. In our laboratory, the CRISPR gene editing system was utilized to knock out the VHL gene in several RCC cell lines. Orthotopic implantation of heterogeneous ccRCC populations to the renal capsule created novel ccRCC models that develop robust lung metastases in immunocompetent mice. The second model is the chicken chorioallantoic membrane (CAM) system. In comparison to the mouse model, this model is more time, labor, and cost-efficient. This model also supported robust tumor formation and intravasation. Due to the short 10 day period of tumor growth in CAM, no overt metastasis was observed by immunohistochemistry (IHC) in the collected embryo tissues. However, when tumor growth was extended by two weeks in the hatched chicken, micrometastatic ccRCC lesions were observed by IHC in the lungs. These two novel preclinical models will be useful to further study the molecular mechanism behind metastasis, as well as to establish new, patient-derived xenografts (PDXs) toward the development of novel treatments for metastatic ccRCC.

Using the Chicken Chorioallantoic Membrane In Vivo Model to Study Gynecological and Urological Cancers

Mouse models are the benchmark tests for in vivo cancer studies. However, cost, time, and ethical considerations have led to calls for alternative in vivo cancer models. The chicken chorioallantoic membrane (CAM) model provides an inexpensive, rapid alternative that permits direct visualization of tumor development and is suitable for in vivo imaging. As such, we sought to develop an optimized protocol for engrafting gynecological and urological tumors into this model, which we present here. Approximately 7 days postfertilization, the air cell is moved to the vascularized side of the egg, where an opening is created in the shell. Tumors from murine and human cell lines and primary tissues can then be engrafted. These are typically seeded in a mixture of extracellular matrix and medium to avoid cellular dispersal and provide nutrient support until the cells recruit a vascular supply. Tumors may then grow for up to an additional 14 days prior to the eggs hatching. By implanting cells stably transduced with firefly luciferase, bioluminescence imaging can be used for the sensitive detection of tumor growth on the membrane and cancer cell spread throughout the embryo. This model can potentially be used to study tumorigenicity, invasion, metastasis, and therapeutic effectiveness. The chicken CAM model requires significantly less time and financial resources compared to traditional murine models. Because the eggs are immunocompromised and immune tolerant, tissues from any organism can potentially be implanted without costly transgenic animals (e.g., mice) required for implantation of human tissues. However, many of the advantages of this model could potentially also be limitations, including the short tumor generation time and immunocompromised/immune tolerant status. Additionally, although all tumor types presented here engraft in the chicken chorioallantoic membrane model, they do so with varying degrees of tumor growth.

Mouse- and patient-derived CAM xenografts for studying metastatic renal cell carcinoma

Renal cell carcinoma is the seventh most common cancer in the United States, and its metastatic form has a very poor prognosis due to a lack of effective treatment and thorough understanding on metastatic mechanism. This chapter will demonstrate a novel concept that intratumoral heterogeneity is essential for metastasis in renal cell carcinoma. We will first introduce the in vitro system and the mouse model that led to the finding of the cooperative mechanism for metastasis. Then, the results from the CAM model illustrate the cooperative interactions that lead to metastasis also occur in this model. We believe that the CAM model, as a unique and sustainable system, can open up new opportunities to study the metastatic disease.

P3704Silent ischemic brain lesion detected in patients with subclinical paroxysmal atrial fibrillation

Background

Long-lasting atrial fibrillation (AF) has been reported to be associated with an increased risk of dementia, independent of clinical stroke. However, the mechanisms or association in patients with subclinical paroxysmal AF (S-PAF) remain unclear. We evaluated whether S-PAF is associated with silent ischemic brain lesion (S-IBL), one of causes of dementia.

Methods

We studied 46 patients (35 male, 68±15 yrs) without a history of stroke/transient ischemic attack and AF, who implanted insertable cardiac monitoring (ICM) for unexplained syncope (n=33) or embolic stroke of undetermined source (ESUS) (n=13). All patients underwent cerebral magnetic resource imaging (c-MRI), and S-IBL was defined as infarction, lacuna and microbleeds. The lesions in an acute stage were excluded in patients with ESUS.

Results

AF was detected in 15/46 patients (11 with unexplained syncope and 4 with ESUS) during follow-up of 7.0±6.6 months, and S-IBL was observed in 18/46 patients (9 infarction, 8 lacuna, or 8 microbleeds). Univariate analysis revealed that higher prevalence of AF (61% vs. 14%, p=0.0015), elder age (73±10yrs vs. 65±16yrs, p=0.0445), dyslipidemia (67% vs. 25%, p=0.007), structural heart disease (44% vs. 14%, p=0.0383), and larger left atrium diameter (41±6 mm vs. 37±5 mm, p=0.0267) were related to S-IBL. On multivariate analysis, prevalence of AF was independently associated with S-IBL (p=0.0070, OR 13.4, 95% CI 1.945–155.813). When receiver-operating-characteristics (ROC) curve analysis and prevalence of AF were used to detect S-IBL, the area under the ROC curve was 0.7341 (sensitivity: 61.1%, specificity: 85.7%).

Conclusion

Subclinical paroxysmal AF is associated with silent ischemic brain lesion and might cause to dementia.

P5654Brain natriuretic peptide and left atrial volume predict the reduced flow velocity of left atrial appendage during sinus rhythm in patients with atrial fibrillation

Background

It remains controversial whether or not to discontinue anticoagulation therapy after catheter ablation (CA) for atrial fibrillation (AF). The reduced flow velocity of the left atrial appendage (FV-LAA) during AF causes left atrial appendage thrombus and increases the risk of stroke. However, some AF patients show reduced FV-LAA even during sinus rhythm (SR).

Methods

398 patients who showed SR during transesophageal echocardiography (TEE) before CA for AF were studied (259 males, 68±10 years, 77 with non-paroxysmal AF). Clinical factors, transthoracic echocardiography and blood samples were obtained before TEE. Reduced FV-LAA was defined as <35 cm/sec of FV-LAA.

Results

Reduced FV-LAA was observed 70/398 patients (18%). Reduced FV-LAA was significantly associated with elevated brain natriuretic peptide (BNP) (p<0.0001), increased LA volume index (p<0.0001), reduced left ventricular ejection fraction (p=0.0017), high prevalence of non-paroxysmal AF (p=0.0048), prior history of heart failure (p=0.0172), and no administration of angiotensin converting enzyme inhibitor/angiotensin II receptor blocker (ACEI/ARB) (p=0.0403), while CHADS2 factors were not significantly associated.

On multivariate analysis, LA volume index (p<0.0001, OR 1.049 for each 1 increase in LA volume index, 95% CI 1.025–1.073) and no administration of ACEI/ARB (p=0.0015, OR 0.339 for administration, 95% CI 0.173–0.662) and BNP (p=0.0048, OR 1.035 for each 10 pg/ml increase in BNP, 95% CI 1.011–1.061) and were associated with reduced FV-LAA.

Rate of reduced flow velocity

Conclusion

The elevated BNP level and large LA volume index predict reduced FV-LAA during SR. AF patients with increased BNP and larger LA volume index might require long-term anticoagulation taking after CA procedure.

Establishment of xenografts of urological cancers on chicken chorioallantoic membrane (CAM) to study metastasis

Cancer of the urological system commonly occurs in the kidney, bladder, and prostate gland. The clear cell subtype of renal cell carcinoma (ccRCC) constitutes the great majority of kidney cancer. Metastatic ccRCC portends a very poor outcome with no effective treatment available. Prostate cancer is the most common cancer in males in the US. Despite recent advances in selective kinase inhibitors and immunotherapies, the rate of developing new treatment from bench to bedside is slow. A time-consuming step is at the animal drug testing stage, in which the mouse model is the gold standard. In the pursuit to streamline the in vivo cancer biology research and drug development, we explored the feasibility of the chicken chorioallantoic membrane (CAM) model to establish xenografts. The CAM model greatly shortens the time of tumor growth and lowers the cost comparing to immunocompromised mice. We generated CAM xenografts from ccRCC, bladder and prostate cancer, with established cancer cell lines and freshly isolated patient-derived tissues, either as primary tumor cells or small pieces of tumors. The successful CAM engraftment rate from the different tumor sources is 70% or above. Using our previously established metastatic ccRCC mouse model, we showed that the CAM xenograft maintains the same tumor growth pattern and metastatic behavior as observed in mice. Taken together, CAM can serve as a valuable platform to establish new patient-derived xenografts (PDXs) to study tumor biology, thus accelerating the development of individualized treatment to halt the deadly metastatic stage of cancer.

P3790Left ventricular stiffness assessed by diastolic wall strain predicts infrequent atrial fibrillation

Background

Left ventricular (LV) stiffness as the passive LV filling property in the LV diastolic function has been reported to be related with the prevalence of atrial fibrillation (AF). On the other hand, a novel insertable monitoring (ICM) system is a powerful tool to detect AF with rare appearance in patients with embolic stroke of undetermined source (ESUS). We investigated whether the LV stiffness assessed by diastolic wall strain (DWS) predicts infrequent atrial fibrillation.

Methods

Fifty-five patients (41 males, 68±14 years) who underwent ICM implantation for ESUS (n=19) or unexplained syncope (n=36) were studied. DWS, left atrial (LA) stiffness and other measurements were assessed using transthoracic echocardiography before the ICM implantation. DWS was calculated from the M-mode echocardiographic measurement of the LV posterior wall thickness at end-systole (PWs) and end-diastole (PWd) during sinus rhythm, and DWS was defined as PWd/PWs. LA stiffness index was defined as the ratio of E/e' to LA peak strain.

Results

AF was detected in 20 patients (36%) during the follow-up periods (280±243 days). Patients with AF showed reduced DWS (0.30±0.07 vs. 0.41±0.08, p<0.0001), larger LA volume index (39.0±10.9 vs. 32.3±9.0, p=0.0174), and higher age (74.6±10.4 vs. 64.6±14.9, p=0.0105). On the other hand, LA stiffness index, LA function (reservoir, booster, and conduit function estimated by LA volume), and LV relaxation function (E wave, E/A ratio, deceleration time) were not associated with detection of AF. There was no difference on AF detection rate between ESUS and unexplained syncope (26% vs. 42%, p=0.2604). On multivariate analysis, DWS was only independently associated with detection of AF (p<0.0001, OR 5.647 for each 0.1 decrease in DWS, 95% CI 1.084–1.338). Moreover, patients with reduced DWS (<0.38) had a higher risk of incidences of AF than patients with preserved DWS (figure).

Figure 1

Conclusions

LV stiffness assessed by DWS predicts infrequent AF. Reduced LV stiffness rather than LA dysfunction or LV relaxation dysfunction may be the main cause of AF in the early stages.

P5502Comparison of clinical characteristics and prognosis between non-octogenarians and octogenarians with cardiac troponin positive acute myocardial infarction

Background

Cardiac troponin (cTn) is the preferred biomarker for the diagnosis of acute myocardial infarction (AMI). Octogenarians who presented cTn positive AMI are not usually recruited in clinical trials. Therefore, their clinical characteristics and prognosis are rarely investigated.

Objective

To study the characteristics and prognosis in octogenarians who presented cTn positive AMI.

Methods and results

The Japanese registry of acute Myocardial INfarction diagnosed by Universal dEfiniTion (J-MINUET) is a prospective and multicenter registry. A total of 3,283 consecutive AMI patients who were diagnosed by cTn-based criteria were included. The patients were divided into non-octogenarians (n=2,593) and octogenarians (n=690). Compared with non- octogenarians, octogenarians showed significantly lower incidence of diabetes mellitus (37.6% and 31.9%, p=0.006) and dyslipidemia (53.6% and 45.6%, p<0.001), and significantly higher incidence of hypertension (64.1% and 75.3%, p<0.001) and chronic kidney disease (38.7% and 68.7%, p<0.001). Octogenarians showed significantly longer onset to door time (p<0.001) and longer door to device time (p<0.001). Though, compared with non-octogenarians, octogenarians showed lower peak CK (2,506 and 1,926, p<0.001), LVEF was significantly lower in octogenarians (54.6% and 52.6%, p=0.005). The presentation of AMI was different between the two group. The incidence of ST-segment elevation MI (STEMI) was 70.7% in non-octogenarians and 62.0% in octogenarians. Non-STEMI with CK elevation and without CK elevation were 16.2% and 13.1% in non- octogenarians, and 20.9% and 17.1% in octogenarians. In-hospital mortality was higher in octogenarians (4.7% and 13.2%, P<0.001). Especially, octogenarians with STEMI and non-STEMI with CK elevation showed the highest in-hospital mortality. And octogenarians without CK elevation showed similar in hospital mortality with non-octogenarians with STEMI (Figure).

Conclusions

J-MINUET showed the poor prognosis of octogenarians who were diagnosed as AMI based on cTn.

Acknowledgement/Funding

None

P3392Potential of imaging-guided PCI for event suppression in Japanese acute myocardial infarction patients: J-MINUET substudy

Background

Intravascular ultrasound (IVUS) and Optical Coherence Tomography (OCT) has been widely used in clinical settings. Although favorable results of imaging-guided percutaneous coronary intervention (PCI) compared with angio-guided PCI were observed in several studies, impacts of institutional-based usage frequency, about imaging-guided PCI, have not been well elucidated.

Methods

To elucidate the impact of imaging-guided PCI and the effects of frequency of its usage, we analyzed data of the Japanese registry of acute Myocardial INfarction diagnosed by Universal dEfiniTion (J-MINUET). This was a prospective and multicenter registry consisting of 3,283 AMI patients, who were hospitalized within 48 hours of onset from July 2012 to March 2014. Clinical follow-up data was obtained for 3 years. In this sub-study, a total of 2,788 patients who underwent urgent PCI having detailed procedural information were enrolled. We analyzed the differences of utilization rates of imaging-guided PCI among the participating institutions and the impacts for the clinical events. The participating institutions were divided into 3 groups by the frequency of IVUS usage: low frequency institutions: under 50%; moderate frequency institutions: 50% to 90%; and, high frequency institutions: over 90%.

Results

In this cohort registry, patients were enrolled from 28 institutions. The utilization rate of coronary imaging varied widely depending on each institution from 15.4% to 100% (mean 85.7%±24.3, median 97.4%). When the institutions were divided into 3 groups by the frequency of intravascular imaging usage, four low frequency institutions enrolled 295 patients, five moderate frequency institutions enrolled 624 patients, and 19 high frequency institutions enrolled 1,491 patients. Although the incidence of MACE (death, MI, stroke, cardiac failure, or revascularization for unstable angina) decreased stepwise (33.2%, 23.7%, and 19.7%) (gray bar in the Figure), the event rates of the imaging-guided PCI cases among the 3 groups were comparable (21.6%, 21.9%, and 19.6%) (white bar in the Figure). On the other hand, a gradual event reduction between the 3 groups was observed in the angio-guided PCI cases (black bar in the Figure). In comparison of MACE rate between imaging-guided and angio-guided PCI, there were statistically significant differences in the low frequency and moderate frequency institutions (p=0.001 and p=0.012, respectively). In contrast, comparable event rates were observed in the high frequency institutions (p=0.441).

MACE rate by imaging usage frequency

Conclusions

In Japanese ACS patients treated with imaging-guided PCI, better suppression of clinical events during 3-year was found in the institutions with the more frequent use of intravascular imaging, mainly due to stepwise event suppression in the cases of angio-guided PCI. On the other hand, the clinical benefit of coronary imaging was obtained independently of the frequency of use and its experience.

P2461The presence of L wave was associated with non-invasively estimated left atrial stiffness in heart failure patients

Background

The mid-diastolic L wave is recorded as mid-diastolic mitral forward flow with conventional Doppler echocardiography. L wave is occasionally detected in heart failure (HF) patients but its mechanism of occurrence is still unknown. It is hypothesized that L wave was induced by a positive atrioventricular gradient caused by left atrial filling via pulmonary veins, and the magnitude of the L wave is augmented by increasing ventricular stiffness. We speculate that also Left atrium (LA) function will relate with the presence of L wave because the L wave flow occurs passing LA. LA function has been known to have reservoir, booster pump and conduit function. It is reported that LA conduit function related to LA stiffness. The aim of this study is to clarify the association between LA functions and presence of L wave in HF patients.

Methods and results

Eighty two patients who admitted to our hospital for HF were enrolled in this study. We performed echocardiography before discharge. LA speckle-tracking strain was analyzed by an external software program using apical 4 chamber view. Reservoir function was measured as peak strain value at end systole, and booster pump function was measured as the value of atrial contraction. Conduit function was calculated as the difference of the peak value at end systole and atrial contraction. There were 23 patients who had L wave before discharge and 59 patients without L wave. Transmitral E wave (E) and left atrial volume index (LAVI) were higher in patients with L wave than in those without L wave. LA reservoir strain was not different in two groups, but poster pump strain was lower and conduit strain was higher in patients with L wave than those without. LA reservoir strain and booster pump strain weakly correlated with A wave velocity (r=0.39 p=0.004, r=46 p=0.001) and LAVI (r=−0.23 p=0.0383, r=−0.31 p=0.005), but conduit strain had no correlation with A wave (r=0.12 p=0.26) and LAVI (r=−0.04 p=0.67). In multivariate regression analysis for the presence of L wave with A wave velocity, LAVI and LA conduit strain, LA conduit strain remained independent predictors of the presence of L wave (HR 1.12 95% CI 1.04–1.23; p=0.004).

Conclusion

LA conduit function was not correlated with conventional echo parameters of LA function (A wave velocity and LAVI). The presence of L wave was associated with LA conduit strain.

P6466Novel index with combined echocardiographic parameter and CT parameter (pPAT) is useful for screening pulmonary hypertension in Systemic Sclerosis Patients

Background

Systemic sclerosis (SSc) patients with pulmonary arterial hypertension (PAH) had poor survival rate. Usual index of estimating PH is tricuspid regurgitate jet pressure gradient (TRPG). Accurate assessment of PAH is important for the management of SSc patients. However, estimated mean pulmonary arterial pressure (mPAP) using TRPG by echocardiography does not always reflect actual mPAP by right heart catheterization (RHC) in SSc patients. On the other hand, recent reports have shown that rPA, a ratio of diameter of pulmonary artery to ascending aorta (PA/Ao) calculated by computed tomography (CT), was associated with mPAP. However, both index are not sufficient for evaluation of PH. We hypothesized that the product of TRPG and rPA (pPAT) could estimate mPAP of SSc patients more accurately than TRPG or rPA.

Purpose

We investigated the usefulness of the product of TRPG and rPA for detecting actual mPAP in SSc patients.

Methods

Thirty-six SSc patients who suspected PH were enrolled retrospectively. We defined PH as resting mPAP from RHC of >25 mmHg. We measured both a widest pulmonary artery diameter and an adjacent ascending aorta diameter at the same level of the bifurcation of the main pulmonary artery using CT images.

Results

The average age was 67 years old and average mPAP by RHC was 24.7 mmHg. Mean TRPG and mean rPA were 35.1 mmHg and 1.06, respectively. Furthermore, mean pPAT was 37.9. We found pPAT had a stronger correlation with actual mPAP (r=0.848, p<0.001) than TRPG (r=0.754, p<0.001) or rPA (r=0.584, p<0.001). On ROC analysis, pPAT predicted PH with high accuracy for a cut-off of 33.1. In order to evaluate the usefulness of pPAT, we compared false-negative patients between two cutoff values of TRPG 34 mmHg described in ESC guideline and pPAT 33.1. Among the patients with TRPG <34mmHg, 4 patients (18%) had PH. In contrast, when screening PH using pPAT, the diagnosis of PH was missed in only one patient.

Figure 1

Conclusion

The product of TRPG and PA/Ao (pPAT) could be a novel and useful noninvasive index for identifying PH in SSc patients.

P5974Prognostic value of global tangential strain by three-dimensional echocardiography heart failure patients with intermediate ECG criteria for cardiac resynchronization therapy

Background

In the current clinical guidelines, cardiac resynchronization therapy (CRT) is recommended in heart failure (HF) patients with left bundle branch block (LBBB) with QRS width ≥150ms as Class I indication. In terms of HF patients with intermediate ECG criteria, prediction for benefit of CRT is still controversial in routine echocardiography.

Purpose

The aim was to assess whether three-dimensional (3D) echocardiographic indexes of global LV function at baseline has a prognostic value following CRT implantation in patients who fulfilled with intermediate ECG criteria.

Methods

We studied 62 HF patients who fulfilled with the indication criteria of CRT implantation according to current the clinical guidelines. In addition to routine two-dimensional echo, 3D echo dataset was acquired for determination of 3D global tangential strain (GTS) and 3D global longitudinal strain (GLS). We tracked predefined unfavorable outcomes for 3 years after CRT implantation: death, hospitalization due to worsening HF.

Results

LBBB with QRS width ≥150ms was evident in 26 of 62 patients (aged 68±11 years with 160±26 ms of QRS duration and 29±7% of LV ejection fraction), and the other 36 patients only fulfilled intermediate ECG criteria (QRS width 120–149ms or non-LBBB). Unfavorable events occurred in 21 patients (34%). The median GTS was −15.4%. Although GLS was not predictive, GTS greater than −15.4% had high probability of unfavorable outcomes over 3 years (Log-rank, p<0.05). There is no difference in the probability of unfavorable outcomes between LBBB and intermediate ECG criteria. Baseline GTS in patients with intermediate ECG criteria was associated with unfavorable outcomes: −12.6±2.6% vs. −17.3±3.8% (p<0.05). Outcome was better in the intermediate ECG criteria patients with GTS ≤−15.4% than in those with LBBB and in those with intermediate ECG criteria patients with GTS >−15.4% (Log-rank: p<0.05, p<0.0001, respectively).

Conclusions

Baseline GTS by 3D echocardiography is useful for predicting outcome over 3 years after CRT implantation regardless of the ECG criteria for CRT indication.

P4591Impact of extent of non-culprit lesions on one-year outcomes in patients with acute myocardial infarction

Background

Presence of severe stenosis in non-infarct related arteries, i.e. multi-vessel disease (MVD), is associated with poor outcomes after acute myocardial infarction (AMI). However, impact of mild to moderate stenosis in non-culprit lesions remains unclear.Gensini score is an angiographic application grading the extent of coronary artery lesions including mild to moderate stenosis.

Purpose

To evaluate whether the extent of non-culprit lesion is related to one-year outcomes after AMI.

Methods

This study consisted of consecutive 168 patients who underwent primary percutaneous coronary intervention (PPCI) for AMI between 2015 and 2017. Patients with coronary bypass grafts were excluded from the analysis. To assess the extent of non-culprit lesions, we used “non-culprit Gensini score”, which is calculated by excluding score of the culprit lesion from the original Gensini score. Patients were divided into 2 groups by the median ofnon-culprit Gensini score: low score (0–14, n=84) and high score (>15, n=84). Major adverse cardiac events (MACE) included all cause of deaths, non-fatal MI, stroke and ischemia driven coronary revascularization during one-year follow-up period.

Results

MVDwas more frequent in patients with high score than those in those with low score (90% vs 25%, P<0.05). Kaplan-Mayer curves of patients with and without MVD are shown in left figure, and curves of patients with low score and those with high score are shown in right figure. Multivariable analysis showed that high score was an independent predictor of one-year MACE (HR 5.28, 95% CI 1.93–14.9, P<0.05), but MVD was not (HR 0.56, 95% CI 0.23–1.54, P=0.25) (Table).

Multivariable analyses Univariable analyses Multivariable analyses HR (95% CI) P-value HR (95% CI) P-value Age 1.03 (1.01, 1.06) <0.05 1.15 (0.99, 1.05) 0.31 eGFR (<45ml/min/1.73m2) 2.95 (1.59, 5.38) <0.05 2.35 (1.26, 4.35) <0.05 Multi-vessel disease 1.84 (1.01, 3.55) <0.05 0.56 (0.23, 1.54) 0.25 Non-culprit-Gensini score (>15) 3.37 (1.79, 6.78) <0.05 5.28 (1.93, 14.9) <0.05 HR = hazard ratio; CI = confidence interval; eGFR = estimated glomerular filtration rate.

Kaplan-Meier curves

Conclusion

These findings suggested that extent of mild to moderate stenosis in non-culprit lesions might affect the prognosis after AMI in patients undergoing PPCI. Non-culprit Gensini score may be useful to predict outcomes of patients with AMI.

Acknowledgement/Funding

None

P1954Prognostic value of the CHADS2 score for adverse cardiovascular events in acute myocardial infarction patients without atrial fibrillation: J-MINUET Substudy

Background

The CHADS2score has mainly been used to predict the likelihood of cerebrovascular accidents in patients with atrial fibrillation. However, increasing attention is being paid to this scoring system for risk stratification of patients with coronary artery disease. We investigated the value of the CHADS2 score in predicting cardiovascular events in Japanese acute myocardial infarction (AMI) patients without atrial fibrillation.

Methods

To elucidate the prognostic value of CHADS2score in AMI patients, we analysed data of the Japanese registry of acute Myocardial INfarction diagnosed by Universal dEfiniTion (J-MINUET). This was a prospective and multicenter registry consisting of 3,283 AMI patients, who were hospitalized within 48-hours of onset from July 2012 to March 2014. We calculated the CHADS2 scores for 3,044 patients without clinical evidence of atrial fibrillation. The presence of heart failure was substituted by Killip classification>2 on admission. Clinical follow-up data was obtained for 3 years. In addition to the in-hospital mortality,we evaluated cardiovascular events, defined as all cause deathor non-fatal MI during 3-year follow up periods.

Results

In this study, enrolled patients were classified into low- (point 0–1), intermediate- (point 2–3), and high-score (point 4–6) groups by calculating CHADS2 score. Overall patients with low, intermediate and high score were divided into 1,395, 1,393 and 256 patients, respectively. In-hospital mortality among low, intermediate, and high score groups were 2.8%, 7.4% and 14.8%, respectively (P<0.001). The incidence of cardiovascular eventsamong low, intermediate, and high score groups were 7.8%, 16.3%, 29.3%, respectively (P<0.001). Kaplan-Meier analysis showed a significant difference between the groups (Figure). The event rates were significantly higher in both high score and intermediate score group than in low score group (P<0.001). Multivariate Cox hazard analysis identified CHADS2 score (per 1 point) as an independent predictor of cardiovascular events in addition to chronic kidney disease and lower body mass index. (hazard ratio, 1.344; 95% CI, 1.239–1.459; P<0.001). Among the factors constituting CHADS2 score, heart failure and age were identified as independent predictors for in-hospital mortality. With respect to the cardiovascular event during 3 years, heart failure, age, and previous stroke were revealed as significant independent predictors.

Conclusion

This large cohort study indicated that the CHADS2 score is useful for the prediction of in-hospital mortality and the cardiovascular events during 3-year follow up in Japanese AMI patients without atrial fibrillation.

P3406Validation of atherothrombotic risk score for secondary prevention in patients with acute myocardial infarction: the J-MINUET study

Background

Thrombolysis in Myocardial Infarction (TIMI) Risk Score for Secondary Prevention and CREDO-Kyoto Thrombotic Risk Score are contemporary secondary prevention risk scoring systems. However, these scoring systems have not been validated in other populations.

Purpose

The aim of this study was to validate of the TIMI Risk Score for Secondary Prevention and CREDO-Kyoto Thrombotic Risk Score in patients in the early phase of acute myocardial infarction (AMI).

Methods

The Japanese registry of acute Myocardial INfarction diagnosed by Universal dEfiniTion (J-MINUET) is a prospective multicenter registry conducted in 28 Japanese medical institutions. We enrolled 3,283 consecutive patients with AMI who were admitted to participating institutions within 48 hours of symptom onset between July 2012 and May 2014. Among them, 3,070 patients were included in this study after excluding 213 patients who died in the hospital. Clinical follow-up data were obtained up to 3 years. The primary endpoint was a composite of all-cause death, non-fatal MI and non-fatal stroke. The patients were stratified by the TIMI Risk Score for Secondary Prevention and CREDO-Kyoto Thrombotic Risk Score.

Results

At the 3-year follow-up, the primary endpoint had occurred in 337 patients (11.0%). All-cause death, non-fatal MI and non-fatal stroke had occurred in 177 (5.8%), 80 (2.6%) and 80 (2.6%) patients, respectively. TIMI Risk Score for Secondary Prevention and CREDO-Kyoto Thrombotic Risk Score showed a graded association with the composite of all-cause death, non-fatal MI and non-fatal stroke at 3 years in the J-MINUET population (Figure).

Validation of atherothrombotic risk

Conclusions

TIMI Risk Score for Secondary Prevention and CREDO-Kyoto Thrombotic Risk Score were shown to be applicable to the patients in the early phase of AMI.

Beam Energy and Centrality Dependence of Direct-Photon Emission from Ultrarelativistic Heavy-Ion Collisions

The PHENIX collaboration presents first measurements of low-momentum (0.4<p_{T}<3  GeV/c) direct-photon yields from Au+Au collisions at sqrt[s_{NN}]=39 and 62.4 GeV. For both beam energies the direct-photon yields are substantially enhanced with respect to expectations from prompt processes, similar to the yields observed in Au+Au collisions at sqrt[s_{NN}]=200. Analyzing the photon yield as a function of the experimental observable dN_{ch}/dη reveals that the low-momentum (>1  GeV/c) direct-photon yield dN_{γ}^{dir}/dη is a smooth function of dN_{ch}/dη and can be well described as proportional to (dN_{ch}/dη)^{α} with α≈1.25. This scaling behavior holds for a wide range of beam energies at the Relativistic Heavy Ion Collider and the Large Hadron Collider, for centrality selected samples, as well as for different A+A collision systems. At a given beam energy, the scaling also holds for high p_{T} (>5  GeV/c), but when results from different collision energies are compared, an additional sqrt[s_{NN}]-dependent multiplicative factor is needed to describe the integrated-direct-photon yield.