Coil Embolization for Asymptomatic Low-grade Vertebral Artery Injury which Worsened after Cervical Decompression Surgery: A Case Report

Introduction

Blunt cervical injuries rarely cause vertebral artery injuries (VAIs), such as vertebral artery (VA) dissection or occlusion. To prevent subsequent embolic infarction, embolization of the injured VA is needed before surgical fixation of the cervical spine. However, evidence on endovascular treatment for asymptomatic low-grade VAIs with blunt traumatic cervical injury is insufficient.

Case Report

In the present case, a 79-year-old Japanese man presented tetraparesis after falling while walking. Digital subtraction angiography showed no intimal flap and only slight stenosis of the right VA. Embolization was not performed before spinal decompression surgery for this low-grade injury. However, on the 3rd day after surgery, diffuse-weighted imaging showed dot-like high signal intensity in the right thalamus and right posterior lobe, and magnetic resonance angiography (MRA) showed near occlusion of the right VA. 8 days after surgery, MRA showed recanalization of the right VA flow. We performed VA embolization to prevent emboli scattering to the distal region during recanalization of the intracranial blood flow.

Conclusion

According to the relevant literature, prophylactic embolization may be indicated to prevent the embolic infarction not only in cases of VA occlusion requiring fixation of the cervical spine but also in cases of low-grade VAIs in which fixation is not required. Embolization of the VA before spinal surgery might be an aggressive treatment strategy that avoids serious embolic infarction disorder after VAIs.

Language Barriers in Organismal Biology: What Can Journals Do Better?

In the field of organismal biology, as in much of academia, there is a strong incentive to publish in internationally recognized, highly regarded, English-language journals to promote career advancement. This expectation has created a linguistic hegemony in scientific publishing, whereby scholars for whom English is an additional language face additional barriers to achieving the same scientific recognition as scholars who speak English as a first language. Here, we surveyed the author guidelines of 230 journals in organismal biology with impact factors of 1.5 or greater for linguistically inclusive and equitable practices and policies. We looked for efforts that reflect first steps toward reducing barriers to publication for authors globally, including the presence of statements that encouraged submissions from authors of diverse nationalities and backgrounds, policies regarding manuscript rejection based on perceived inadequacies of the English language, the existence of bias-conscious reviewer practices, whether translation and editing resources or services are available, allowance for non-English abstracts, summaries, or translations, and whether journals offer license options that would permit authors (or other scholars) to translate their work and publish it elsewhere. We also directly contacted a subset of journals to verify whether the information on their author guidelines page accurately reflects their policies and the accommodations they would make. We reveal that journals and publishers have made little progress toward beginning to recognize or reduce language barriers. Counter to our predictions, journals associated with scientific societies did not appear to have more inclusive policies compared to non-society journals. Many policies lacked transparency and clarity, which can generate uncertainty, result in avoidable manuscript rejections, and necessitate additional time and effort from both prospective authors and journal editors. We highlight examples of equitable policies and summarize actions that journals can take to begin to alleviate barriers to scientific publishing.

Direct observations of energy transfer from resonant electrons to whistler-mode waves in magnetosheath of Earth

Electromagnetic whistler-mode waves in space plasmas play critical roles in collisionless energy transfer between the electrons and the electromagnetic field. Although resonant interactions have been considered as the likely generation process of the waves, observational identification has been extremely difficult due to the short time scale of resonant electron dynamics. Here we show strong nongyrotropy, which rotate with the wave, of cyclotron resonant electrons as direct evidence for the locally ongoing secular energy transfer from the resonant electrons to the whistler-mode waves using ultra-high temporal resolution data obtained by NASA’s Magnetospheric Multiscale (MMS) mission in the magnetosheath. The nongyrotropic electrons carry a resonant current, which is the energy source of the wave as predicted by the nonlinear wave growth theory. This result proves the nonlinear wave growth theory, and furthermore demonstrates that the degree of nongyrotropy, which cannot be predicted even by that nonlinear theory, can be studied by observations.

Excitation of whistler-mode waves by cyclotron instability is considered as the likely generation process of the waves. Here, the authors show direct observational evidence for locally ongoing secular energy transfer from the resonant electrons to the whistler-mode waves in Earth’s magnetosheath.

Cardiopulmonary arrest and in-hospital outcomes in young patients with acute myocardial infarction: insights from the Japanese nationwide registry

Background

Cardiopulmonary arrest (CPA) is the most serious presentation of acute myocardial infarction (AMI). However, the frequency and prognostic impact of CPA in young patients with AMI have been still unclear.

Objectives

This study aimed to characterize AMI in young patients who underwent primary percutaneous coronary intervention using large-scale nationwide all-comer registry data in Japan (J-PCI registry).

Methods

Data on risk factor profiles, clinical features, post-procedural complications, and in-hospital outcomes were reviewed within the J-PCI registry between 2014 and 2018.

Results

Among 213,297 patients with AMI, 23,985 (11.2%) were young (age, 20–49 years). Compared with the older group (age, 50–79 years; n=189,312), the young group included a higher number of men, smokers, patients with dyslipidemia, and patients with single-vessel disease, and a lower number of patients with hypertension and diabetes. Despite favorable clinical profiles, younger age was associated with a higher rate of presentation with CPA (Figure 1). Further, concomitant CPA was strongly associated with in-hospital mortality in the young group (Table 1).

Conclusions

Young patients with AMI presented a higher risk of CPA than older patients, which was strongly associated with in-hospital mortality.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): JSPS KAKENHI

OP0008 A NOVEL SITE-SPECIFIC PEGYLATED IL-2 WITH POTENT AND TREG-SELECTIVE ACTIVITY IN VIVO

Background

Decreased regulatory T cells (Tregs) and Treg dysfunction are hallmarks of a various autoimmune and inflammatory diseases. While low-dose IL-2 therapy induces Treg expansion in vivo and has clinical benefits in some diseases (e.g., SLE and chronic graft-versus-host disease [GvHD]), there are many concerns about adverse events due to low Treg-selectivity. Furthermore, frequent dosing is needed due to the short half-life.

Objectives

We discovered a novel site-specific PEGylated IL-2 variant, KKC80, with high Treg selectivity and a long half-life in vivo, which overcomes the issues of low-dose IL-2 therapy.

Methods

Based on the co-crystal structure of wild-type IL-2 and its heterotrimeric receptor (PBD ID: 2ERJ), amino acid residues that were to be PEGylation sites were substituted with oAzZLys, an azide-containing lysine derivative. The PEG molecule was site-specifically attached to oAzZLys-incorporated IL-2 by copper-free click chemistry. The binding property to the IL-2 receptors were measured by surface plasmon resonance (SPR). In vitro, Treg selectivity was evaluated by the IL-2-dependent proliferation activity of Tregs and NK cells from human peripheral blood mononuclear cells (PBMCs). In vivo pharmacological activity after the single subcutaneous administration in cynomolgus monkeys was measured by changes in Treg count and Treg activation status in peripheral blood by flow cytometry. Pharmacokinetic parameters were calculated according to serum PEGylated IL-2 concentration. Efficacy in mouse xenogeneic GvHD model using human PBMC-transplanted NOG mice and in monkey DTH model were evaluated.

Results

A novel PEGylated IL-2, KKC80 (human IL-2 desA1/C125S /I129oAzZLys_W-shaped 80 kDa PEG) was discovered by optimizing the PEGylation site and PEG structure based on Treg selectivity and PK. SPR analysis showed that the binding affinity of KKC80 to CD25 was moderately decreased from wild-type IL-2, while binding affinity of KKC80 to IL-2Rβγ was remarkably decreased due to a significant change of the association rate constant. In vitro, wild-type IL-2 activated both Tregs and NK cells in the same concentration range, whereas KKC80 selectively activated Tregs. The Treg selectivity of KKC80 was comparable to another IL-2 mutein, Fc.IL-2 V91K. KKC80, but not Fc.IL-2 V91K, retained its biological activity, even in the presence of a large amount of recombinant soluble CD25, which mimicked the endogenous decoy receptor for IL-2. In monkeys, KKC80 selectively increased peripheral blood Tregs in a dose-dependent manner; the average maximum rate of increase of Treg count in animals treated with 0.01, 0.03, 0.1, 0.3 and 1 mg/kg was 1.5, 3.5, 28, 50 and 154-fold, respectively. In contrast to Tregs, the rates of increase of conventional CD4+ T, CD8+ T and NK cells were low. The Treg increase peaked on day 8 or 11 and lasted for over day 29. KKC80 showed a more sustained upregulation of functional Treg markers (e.g., Foxp3 and CD25) in comparison to Fc.IL-2 V91K. The half-life of KKC80 was calculated as 83.5 to 150 h. At high doses, inflammation-related adverse effects, including increased CRP (≥0.3 mg/kg) and deterioration of general conditions (1 mg/kg) were observed. In the mouse xenogenic GvHD model, KKC80 ameliorated GvHD symptoms and suppressed multiple tissue inflammation markers. Decreased soluble CD25 and IFN-γ were also confirmed, suggesting Treg-mediated anti-inflammatory effect by KKC80 administration were exerted in vivo. In the monkey DTH model, KKC80 suppressed skin inflammation and antibody production.

Conclusion

Among next-generation IL-2 variants, KKC80 showed a best-in-class biological profile for Treg activation. A drastic and sustained increase of Tregs with high Treg-selectivity and anti-inflammatory effects were observed in vivo. These data suggest that in comparison to current IL-2 therapy, KKC80 provides superior therapeutic index and efficacy in patients with autoimmune and inflammatory diseases.

Figure 1.

Disclosure of Interests

Masahiro Ikeda Employee of: Kyowa Kirin Co., Ltd., Shinpei Yamaguchi Employee of: Kyowa Kirin Co., Ltd., Masumi Murakami Employee of: Kyowa Kirin Co., Ltd., Shigeki Takaoka Employee of: Kyowa Kirin Co., Ltd., Yasuko Sakaguchi Employee of: Kyowa Kirin Co., Ltd., Shunki Yasui Employee of: Kyowa Kirin Co., Ltd., Kousuke Iijima Employee of: Kyowa Kirin Co., Ltd., Kenichiro Nanya Employee of: Kyowa Kirin Co., Ltd., Hideyuki Onodera Employee of: Kyowa Kirin Co., Ltd., Toru Amano Employee of: Kyowa Kirin Co., Ltd.

Trans-stenotic pressure gradient as derived from CT improves patient management: ADVANCE registry

Background

The change in fractional flow reserve derived from CT (FFRCT) value across a coronary stenosis (ΔFFRCT) improves the physiological characterization of coronary artery disease (CAD). The role of ΔFFRCT in guiding risk-stratification and downstream testing in patients with stable CAD is unknown.

Purpose

To investigate the incremental value of ΔFFRCT at predicting early revascularization and improving efficacy of resource utilization.

Methods

Patients with CAD on CT coronary angiography (CTCA) were enrolled in an international multicenter registry. Patients with non-evaluable FFRCT analysis were excluded. The CTCA was assessed for: stenosis severity as per CAD-Reporting and Data System (CAD-RADS), lesion length and lesion-specific FFRCT measured 2 cm distal to stenosis. Risk factors and actual treatment (revascularization vs medical therapy) at 90-day follow-up were recorded. Multivariable logistic regression analysis for early revascularization was conducted. The incremental discrimination for revascularization prediction was compared among 3 models (model 1: risk factors + lesion length and location + CAD-RADS; model 2: model 1 + lesion-specific FFRCT; model 3: model 2 + ΔFFRCT). Simulating ICA referral for patients with CAD-RADS ≥3 and lesion-specific FFRCT ≤0.8, the potential impact of ΔFFRCT at reducing ICA referral and improving the ratio of subsequent revascularization was assessed.

Results

Of 4730 patients (66±10 years; 34% female), 2092 (42.7%) underwent ICA and 1168 (24.7%) underwent early revascularization. With increasing ΔFFRCT, a higher incidence of revascularization (Figure 1A) and an increase in the revascularization to ICA ratio was observed (Figure 1B). ΔFFRCT >0.13 was the optimal cut-off for predicting revascularization as determined by the Youden index. ΔFFRCT remained an independent predictor for early revascularization (odds ratio per 0.05 increase with 95% CI, 1.31 [1.26–1.35]; p<0.0001) after adjusting for risk factors, CAD-RADS, lesion length and location, and FFRCT. Among the 3 models, model 3, which included ΔFFRCT showed the highest AUC and improved discrimination power compared to model 2 (0.87 [0.86–0.88] vs 0.85 [0.84–0.86]; p<0.0001] (Figure 2), with the greatest incremental value for ΔFFRCT observed in patients with lesion-specific FFRCT between 0.71–0.80. In patients with CAD-RADS ≥3 and lesion-specific FFRCT ≤0.8, a diagnostic strategy incorporating ΔFFRCT >0.13 would potentially reduce ICA referral by 32.2% (1638 to 1110) and improve the revascularization to ICA ratio from 65.2% [1068/1638] to 73.1% [811/1110].

Conclusions

The characterization of CAD with ΔFFRCT improves the identification of patients requiring early revascularization as compared to a standard diagnostic strategy of CTCA with FFRCT, particularly for those with lesion-specific FFRCT of 0.71–0.80. ΔFFRCT has the potential to aid decision making for ICA referral and improve the efficiency of resource utilization.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): HeartFlow, Inc., Redwood City, CA, USA ΔFFRCT and actual treatmentROC curve for early revascularization

Differential impact of renal function on the diagnostic performance of resting full-cycle ratio as non-hyperemic physiological assessment

Background

Fractional flow reserve (FFR) is a gold standard method to evaluate functional lesion severity in daily clinical practice. Recently, the resting full-cycle ratio (RFR) was Previous studies showed the better diagnostic performance of RFR comparing with FFR. It is well known that patients with chronic kidney disease (CKD) have poor prognosis. Therefore, we should carefully assess the functional lesion severity in CKD patients. However, it is unclear whether the diagnostic performance of RFR for detecting functional ischemia is similar regardless of the degree of renal function. The aim of this study is to compare the diagnostic performance of RFR based on renal function.

Method

This study was a prospectively enrolled observational study. A total of 265 consecutive patients with 373 intermediate lesions were enrolled in this study. There were classified into three groups according to renal function (Group 1: eGFR ≥60 mL/min/1.73m2; Group 2: 30 mL/min/1.73m2 ≤eGFR <60 mL/min/1.73m2; Group 3: eGFR <30mL/min/1.73m2). The RFR was measured after adequately waiting for stable condition, while FFR was measured after intravenous administration of ATP (180mcg/kg/min). The discordance between FFR and RFR were assessed the data using known cutoffs for FFR (≤0.80) and RFR (≤0.89).

Results

Of 373 lesions, the median age was 70.1±11.0 years. Functional significance was observed in 153 lesions (41.0%) of all lesions. RFR showed a significant correlation with FFR in each group (Group 1; r2=0.63 [p<0.001], Group 2: r2=0.67 [p<0.001], Group 3: r2=0.51 [p<0.001], respectively). The ROC curve analysis of RFR showed differential results for predicting functional significance (Group 1: AUC 0.88, cut-off value 0.91; Group 2: AUC 0.88, cut-off value 0.89; Group 3: AUC 0.81, cut-off value 0.83; respectively) in each group. The prevalence of discordant between RFR and FFR was significantly different among 3 groups (Group 1: 16.5%, Group 2: 19.4%, Group 3: 25.0%, respectively, p<0.05 for among 3 groups).

Conclusion

The diagnostic performance of RFR was different based on renal function. During RFR acquisition, the degree of renal function could influence concordance with FFR, and should be taken into account when interpreting RFR.

Funding Acknowledgement

Type of funding sources: None.

CD133 mRNA-transfected dendritic cells induce coordinated cytotoxic and helper T cell responses against breast cancer stem cells

Breast cancer, a leading cause of death yearly, has been shown to be initiated and propagated by cancer stem cells. CD133, a cell surface antigen, has been shown to be present on cancer stem cells of many solid tumors, including breast cancer. A limitation to targeting CD133 is major histocompatibility complex (MHC)-restricted presentation of epitopes, leading to activation of only one arm of the immune system: either CD4+ helper T cells or CD8+ cytotoxic T cells. Thus, we hypothesized that by creating an MHC-independent vaccination, we would give rise to a sustained immune response against CD133 in triple-negative breast cancer (TNBCs). We transfected CD133 mRNA into dendritic cells and then tested this in animal models of TNBC. We showed in these models the activation of both CD8+ cytotoxic T cells and CD4+ helper T cells by dendritic cell vaccination with modified CD133 mRNA, with subsequent decrease in tumor growth. This study for the first time demonstrates in a syngeneic mouse model of TNBC that targeting CD133, in an MHC-independent manner, is an effective strategy against the cancer stem cell population, leading to tumor abrogation.

Diagnostic Accuracy of Diastolic Fractional Flow Reserve for Functional Evaluation of Coronary Stenosis

Background

In the resting conditions, narrowing the window of coronary pressure measurements from the whole cardiac cycle to diastole improves diagnostic performance of coronary pressure–derived physiological index. However, whether this also applies to the hyperemic conditions has not yet been thoroughly evaluated.

Objectives

The purpose of this study was to assess whether diastolic fractional flow reserve (diastolic FFR) has better diagnostic performance in identifying ischemia-causing coronary lesions than conventional FFR in a prospective, multicenter, and independent core laboratory–based environment.

Methods

In this prospective multicenter registry at 29 Japanese centers, we compared the diagnostic performance of FFR, diastolic FFR, resting distal to aortic coronary pressure (Pd/Pa), and diastolic pressure ratio (dPR) using myocardial perfusion scintigraphy (MPS) as the reference standard in 378 patients with single-vessel coronary disease.

Results

Inducible myocardial ischemia was found on MPS in the relevant myocardial territory of the target vessel in 85 patients (22%). In the receiver-operating curve analyses, diastolic FFR had comparable area under the curve (AUC) compared with FFR (AUC_{diastolic FFR}: 0.66; 95% confidence interval [CI]: 0.58-0.73, vs AUC_FFR: 0.66; 95% CI: 0.58-0.74, P = 0.624). FFR and diastolic FFR showed significantly larger AUCs than resting Pd/Pa (0.62; 95% CI: 0.54-0.70; P = 0.033 and P = 0.046) but did not show significantly larger AUCs than dPR (0.62; 95% CI: 0.55-0.70; P = 0.102 and P = 0.113).

Conclusions

Diastolic FFR showed a similar diagnostic performance to FFR as compared with MPS. This result reaffirms the use of FFR as the most accurate invasive physiological lesion assessment. (Diagnostic accuracy of diastolic fractional flow reserve (d-FFR) for functional evaluation of coronary stenosis; UMIN000015906)

Eccrine sweat glands' maximum ion reabsorption rates during passive heating in older adults (50-84 years)

PURPOSE

We examined whether eccrine sweat glands ion reabsorption rate declined with age in 35 adults aged 50-84 years. Aerobic fitness (VO_2max) and salivary aldosterone were measured to see if they modulated ion reabsorption rates.

METHODS

During a passive heating protocol (lower leg 42 °C water submersion) the maximum ion reabsorption rates from the chest, forearm and thigh were measured, alongside other thermophysiological responses. The maximum ion reabsorption rate was defined as the inflection point in the slope of the relation between galvanic skin conductance and sweat rate.

RESULTS

The maximum ion reabsorption rate at the forearm, chest and thigh (0.29 ± 0.16, 0.33 ± 0.15, 0.18 ± 0.16 mg/cm²/min, respectively) were weakly correlated with age (r ≤  - 0.232, P ≥ 0.05) and salivary aldosterone concentrations (r ≤  - 0.180, P ≥ 0.179). A moderate positive correlation was observed between maximum ion reabsorption rate at the thigh and VO_2max (r = 0.384, P = 0.015). Salivary aldosterone concentration moderately declined with age (r =  - 0.342, P = 0.021). Whole body sweat rate and pilocarpine-induced sudomotor responses to iontophoresis increased with VO_2max (r ≥ 0.323, P ≤ 0.027) but only moderate (r =  - 0.326, P = 0.032) or no relations (r ≤  - 0.113, P ≥ 0.256) were observed with age.

CONCLUSION

The eccrine sweat glands' maximum ion reabsorption rate is not affected by age, spanning 50-84 years. Aldosterone concentration in an aged cohort does not appear to modulate the ion reabsorption rate. We provide further support for maintaining cardiorespiratory fitness to attenuate any decline in sudomotor function.

Clinical impact of triglyceride deposit cardiomyovasculopathy, coronary atherosclerosis with triglyceride deposition, on vascular failure after drug-eluting stent implantation

Background

Triglyceride deposit cardiomyovasculopathy (TGCV) is a novel cardiovascular disorder, encoded as orphan disease in Europe in 2019, characterized by excessive accumulation of triglyceride in vascular smooth muscle cells, leading to coronary artery disease (CAD). However, there is no data about impact of TGCV on vascular failure after coronary stent implantation.

Purpose

To assess impact of TGCV on the outcome following coronary stent implantation in CAD patients with diabetes mellitus (DM) as Study 1, and chronic hemodialysis as Study 2.

Methods

This is multicenter retrospective estimation consisting of two studies.

Study 1) Among 526 consecutive patients suspected of having CAD who underwent coronary angiography (CAG) and iodine-123-β-methyliodophenyl-pentadecanoic acid (BMIPP) scintigraphy, a tracer for the diagnosis of TGCV, data from 81 patients with DM were analyzed.

The patients were divided into two groups; TGCV (n=7) or non-TGCV (n=74). All patients were implanted with a second-generation DES and underwent follow-up CAG. Binary restenosis (ISR), defined as angiographic luminal diameter >50% by quantitative coronary angiography, in-stent late loss were assessed in 15 stents of TGCV patients and 111 stents of non-TGCV patients.

Study 2) Similarly, among 88 chronic hemodialysis patients, ISR and in-stent late loss were assessed in 12 stents of 9 TGCV patients and 21 stents of 17 non-TGCV patients.

Results

Study 1) There were no significant differences in baseline characteristics between the two groups. In-stent late loss was greater in TGCV group than in non-TGCV group (0.91mm [0.27, 2.39] vs. 0.15mm [0.03, 0.35]; p<0.001), resulting in greater incidence of ISR in TGCV group than in non-TGCV group (46.7% vs. 9.0%; p<0.001). Multivariable logistic analysis revealed TGCV to be an independent predictor for vascular failure after DES implantation in patients with DM.

Study 2) Similarly, in-stent late loss and incidence of ISR were greater in TGCV group than in non-TGCV group (1.20±0.99mm vs. 0.50±0.70, p=0.02; 58.3% vs. 9.5%, p=0.002, respectively). TGCV was an independent predictor for vascular failure after DES implantation in chronic hemodialysis patients.

Conclusion

Apart from existing risk factors such as DM and hemodialysis, TGCV could contribute to a novel risk factor for vascular failure, even in the second-generation DES era.

Figure 1

Funding Acknowledgement

Type of funding source: None

Differential impact of target vessel on the diagnostic performance of resting full-cycle ratio as non-hyperemic physiological assessment

Background

Recently, wire-based resting indices have been recognized as gold standard for evaluating physiological lesion assessment. The resting full-cycle ratio (RFR) is a unique resting index which is calculated as the point of absolutely lowest distal pressure to aortic pressure during entire cardiac cycle. It is unclear whether the diagnostic performance of RFR for detecting functional coronary artery stenosis is similar in each coronary artery. The aim of this study is to compare the diagnostic performance of RFR based on target coronary vessel.

Method

This study was a prospectively enrolled observational study. A total of 156 consecutive patients with 220 intermediate lesions were enrolled in this study. The RFR was measured after adequately waiting for stable condition, while FFR was measured after intravenous administration of ATP (180mcg/kg/min). Lesions with FFR ≤0.80 were considered functionally significant coronary artery stenosis.

Results

In all lesions, reference diameter, diameter stenosis, lesion length, RFR, and FFR were 3.0±0.7mm, 45±13%, 13.0±8.8mm, 0.90±0.09, and 0.82±0.10, respectively. Functional significance was observed in 88 lesions (40%) of all lesions. RFR showed a significant correlation with FFR in overall lesions (r=0.774, p<0.001). The ROC curve analysis of RFR showed good accuracy for predicting functional significance (AUC 0.87, diagnostic accuracy 81%) in all subjects. Regarding each target vessel, there were similar and significant positive correlation between RFR and FFR (LAD; r=0.733, p<0.001, LCX; r=0.771, p<0.001, RCA; r=0.769, p<0.001, respectively). The prevalence of discordant between RFR and FFR was significantly different among 3 vessels (LAD 26%, LCX 12%, RCA 13%, respectively, p<0.05 for among 3 groups). Regarding the comparison of ROC curves according to lesion location, AUC was significantly lower in LAD than in LCX and RCA (LAD 0.780, LCX 0.947, RCA 0.926, p<0.01 for LAD compared to LCX, p<0.01 for LAD compared to RCA, respectively). Furthermore, the diagnostic accuracy was significantly different according to target vessel (LAD 74%, LCX 88%, RCA 87%, respectively, p<0.05 for among 3 vessels).

Conclusion

RFR demonstrated better diagnostic accuracy for evaluating functional lesion severity. The diagnostic performance of RFR was different based on target vessel. RFR is a unique and useful resting index, and it may detect functionally significant coronary stenosis that cannot be detected with other resting indices in daily practice.

Funding Acknowledgement

Type of funding source: None

Quality and clinical outcomes of primary percutaneous coronary intervention after ST-segment elevation myocardial infarction: a population density analysis of a Japanese nationwide registry

Background

Despite progress in acute myocardial infarction (MI) treatment, data on geographical disparities in its care remain limited.

Purpose

We aimed to assess the discrepancy by population density (PD) on the quality and clinical outcomes of patients with primary percutaneous coronary intervention (PCI) after ST-segment elevation MI (STEMI).

Methods

The J-PCI registry is a prospective procedural registry conducted by the Japanese Association of Cardiovascular Intervention and Therapeutics (CVIT) to assure the quality of delivered care. Between January 2014 and December 2018, 209,521 patients underwent PCI for STEMI in 1,126 institutes. Population of administrative municipal-level districts was determined through the complete population census. The patients were divided into tertiles according to the PD of the PCI institution location (low: <951.7/km2, n=69,797; middle: 951.7–4,729.7/km2, n=69,750; high: ≥4,729.7/km2, n=69,974).

Results

Patients treated in high PD administrative districts were younger (low: 69.1±12.9, middle: 68.7±12.9, high: 68.0±13.1) and likely to be male (low: 75.6%, middle: 76.0%, high: 76.6%). No significant correlation was observed between PD and door-to-balloon time (DTB: regression coefficients: 0.036 per 1000 people/km2, 95% CI: −0.232 to 0.304, P=0.79). Patients treated in low PD areas had higher crude in-hospital mortality rates than those treated in high PD areas (low: 2.89%, middle: 2.60%, high: 2.38%; P<0.001). Moreover, PD and in-hospital mortality had a significantly inverse association, before and after adjusting for baseline characteristics (crude odds ratio [OR]: 0.983 per 1,000/km2, 95% confidence interval [CI]: 0.973–0.992, P<0001; adjusted OR: 0.980 per 1,000/km2, 95% CI: 0.964–0.996, P=0.01, respectively). Higher PD districts had more operators per institute (low: 6, interquartile range [IQR] 3–10; middle: 7, IQR 3–13; high: 8, IQR 5–13, P<0.001), suggesting an inverse association with in-hospital mortality (OR: 0.992, 95% CI: 0.986–0.999, P=0.03).

Conclusions

Marked geographical inequality was observed in immediate case fatality; patients treated in population-dense areas had a lower in-hospital mortality than those treated in less dense areas. Variation in the number of operators per institute, rather than traditional quality indicators (e.g. DTB) may explain the difference in in-hospital mortality.

Funding Acknowledgement

Type of funding source: None

Discordance predictor between fractional flow reserve and resting full-cycle ratio in clinical characteristics

Introduction

Fractional flow reserve (FFR) is a gold standard method to evaluate functional lesion severity in daily clinical practice. Recently, the resting full-cycle ratio (RFR) which was newly developed resting indices was launched. Unlike other resting indices evaluated in diastolic phase, RFR is evaluated during entire cardiac phase. Previous studies showed discordance predictors between FFR and instantaneous wave-free ratio. However, it is previously unreported what predictor cause discordant outcome between FFR and RFR.

Purpose

The purpose of this study was to evaluate clinical predictors of discordance between FFR and RFR.

Methods

A total of 156 patients with 220 lesions were prospectively enrolled in this study. RFR was evaluated before inducing hyperemia. FFR was measured after intravenous adenosine triphosphate administration (180 mcg/kg/min). According to FFR and RFR values, the patients and lesions were classified into 4 groups: Concordant negative (Group-1 [n=114]: FFR >0.80, RFR >0.89); negative FFR and positive RFR (Group-2 [n=18]: FFR >0.80, RFR ≤0.89); positive FFR and negative RFR (Group-3 [n=25]: FFR ≤0.80, RFR >0.89); Concordant positive (Group-4 [n=63]: FFR ≤0.80, RFR ≤0.89). Among them, discordance predictors with clinical characteristics between RFR and FFR were compared using by two separate logistic regression analyses. (Group-1 vs. Group-2, Group-3 vs. Group-4, respectively). Age, sex and those predictors with a p value ≤0.10 were included in a multivariate regression analysis using by forward stepwise selection to identify independent predictors of discordance.

Results

On multiple regression analysis, hemodialysis (HD) (OR:6.072 [1.090–33.836]), peripheral artery disease (PAD) (OR:9.053 [1.776–46.162]) and left anterior descending artery (LAD) (OR:9.264 [2.092–41.031]) were significantly associated with positive RFR among negative FFR groups (Groupe 2 discordance). Conversely, diabetes mellitus (DM) (OR:0.212 [0.062–0.721]) and Hb (OR:1.480 [1.102–1.987]) were significantly associated with negative RFR among positive FFR groups (Groupe 3 discordance)

Conclusions

Since the clinical characteristics with HD, PAD, LAD, DM and Hb may influence concordant with FFR during RFR evaluation, it should be considered when interpreting RFR.

Distribution and independent predictors

Funding Acknowledgement

Type of funding source: None

Diagnostic feasibility of resting full-cycle ratio between systole and diastole to assess functional lesion severity of intermediate coronary artery stenosis

Background

Recently, non-hyperemic physiologic indices have become widespread for evaluating physiological lesion assessment. The resting full-cycle ratio (RFR) is a unique non-hyperemic index which is calculated as the point of absolutely lowest distal pressure to aortic pressure during entire cardiac cycle. It is unclear whether RFR may detect functionally significant coronary stenosis that cannot be detected with other resting indices due to differences in the cardiac cycle. The aim of this study is to compare the diagnostic performance of RFR based on cardiac cycle.

Method

This study was a prospectively enrolled observational study. A total of 156 consecutive patients with 220 intermediate lesions were enrolled in this study. The RFR was measured after adequately waiting for stable condition, while FFR was measured after intravenous administration of ATP (180mcg/kg/min). Lesions with FFR ≤0.80 were considered functionally significant coronary artery stenosis.

Results

In all lesions, reference diameter, diameter stenosis, lesion length, RFR, and FFR were 3.0±0.7mm, 45±13%, 13.0±8.8mm, 0.90±0.09, and 0.82±0.10, respectively. Functional significance was observed in 88 lesions (40%) of all lesions. RFR systole was observed in 24 lesions (10.9%). Regarding to the coronary lesions, RFR systole was more frequent in non-LAD (LAD; 4.2%, left circumflex artery (LCX); 9.8%, and right coronary artery (RCA); 30.4%, respectively, p<0.018). RFR showed a significant correlation with FFR in both systole and diastole (R = 0.918, p<0.001, R = 0.733, p<0.001, respectively). The ROC curve analysis showed similar agreement in both systole and diastole (AUC: 0.881, p<0.001, AUC: 0.864, p<0.001, respectively). RFR provided a good diagnostic accuracy and no difference in both systole and diastole (79.6% and 87.5%, respectively, p=0.58).

Conclusion

RFR is feasible and reliable non-hyperemic index regardless of the difference of cardiac cycle to evaluate physiological lesion severity in daily practice.

Funding Acknowledgement

Type of funding source: None

Intermittent pneumatic compression versus additional prophylaxis with enoxaparin for prevention of venous thromboembolism after laparoscopic surgery for gastric and colorectal malignancies: multicentre randomized clinical trial

Background

The role of antithrombotic chemoprophylaxis in prevention of venous thromboembolism (VTE) in laparoscopic surgery for gastric and colorectal malignancies is unknown. This study compared the addition of enoxaparin following intermittent pneumatic compression (IPC) with IPC alone in patients undergoing laparoscopic surgery for gastrointestinal malignancy.

Methods

In this multicentre RCT, eligible patients were older than 40 years and had a WHO performance status of 0 or 1. Exclusion criteria were prescription of antiplatelet or anticoagulant drugs and history of VTE. Patients were allocated to IPC or to ICP with enoxaparin in a 1 : 1 ratio. Stratification factors included sex, location of cancer, age 61 years and over, and institution. Enoxaparin was administered on days 1–7 after surgery. Primary outcome was VTE, evaluated by multidetector CT on day 7.

Results

Of 448 patients randomized, 208 in the IPC group and 182 in the IPC with enoxaparin group were evaluated. VTE occurred in ten patients (4·8 per cent) in the IPC group and six (3·3 per cent) in the IPC with enoxaparin group (P = 0·453). Proximal deep vein thrombosis and/or pulmonary embolism occurred in seven patients (3·4 per cent) in the IPC group and one patient (0·5 per cent) in the IPC with enoxaparin group (P = 0·050). All VTE events were asymptomatic and non‐fatal. Bleeding occurred in 11 of 202 patients in the IPC with enoxaparin group, and one patient needed a transfusion. All bleeding events were managed by discontinuation of the drug.

Conclusion

IPC with enoxaparin after laparoscopic surgery for gastric and colorectal malignancies did not reduce the rate of VTE. Registration number: UMIN000011667 ( https://www.umin.ac.jp/).

CD133 mRNA-Loaded Dendritic Cell Vaccination Abrogates Glioma Stem Cell Propagation in Humanized Glioblastoma Mouse Model

Cancer stem cells are initiating cells of cancer and propagate its growth through self-renewal and differentiation of its daughter cells. CD133 is a cell surface antigen that is present on glioma stem cells and has been used to prospectively isolate glioma stem cells. We hypothesized that a major histocompatibility complex (MHC)-independent and long-lasting immune response against CD133 could be generated by transfecting CD133 mRNA into dendritic cells and vaccinating animals with experimental gliomas. To test this hypothesis, we developed a novel humanized mouse model using CD34-positive hematopoietic stem cells. We confirmed the robust simultaneous activation of CD8- and CD4-positive T cells by dendritic cell vaccination with modified CD133 mRNA leading to a potent and long-lived immune response, with subsequent abrogation of CD133-positive glioma stem cell propagation and tumor growth. This study for the first time demonstrates in both a humanized mouse model and in a syngeneic mouse model of glioblastoma that targeting a glioma stem cell-associated antigen is an effective strategy to target and kill glioma stem cells. This novel and simple humanized mouse model for immunotherapy is a significant advance in our ability to test human-specific immunotherapies for glioblastoma.

SAT0083 PREVALENCE OF DYSPHAGIA AND ASSOCIATED RISK FACTORS IN ELDERLY PATIENTS WITH RHEUMATOID ARTHRITIS

Background:

Dysphagia (swallowing disorder) is an important health concern among the elderly that is associated with a poor prognosis [1]. Rheumatic diseases such as dermatomyositis are thought to represent an important risk factor for dysphagia, but few studies have described the association between dysphagia and rheumatoid arthritis (RA), and details on the prevalence of dysphagia in RA patients is not known [2] [3].

Objectives:

The present study aimed to determine the prevalence of dysphagia and associated risk factors among elderly patients with rheumatoid arthritis.

Methods:

We conducted a cross-sectional study including 93 patients with RA and osteoarthritis (OA) over 65 years of age. OA patients were included in the study as healthy controls. Patients with a history of stroke, neuromuscular disease, or head and neck tumors were excluded from the study. From July to November 2019, the water swallowing test (WST) and repetitive saliva swallowing test (RSST) were performed to evaluate the presence or absence of dysphagia in the patients. We also checked oral conditions, hoarseness, temporomandibular joint symptoms, cervical range of motion limitations, and grip strength. In addition, interviews were conducted to investigate swallowing ability and aspiration history. We compared the prevalence of dysphagia between RA and OA patients and explored potential risk factors for dysphagia in RA patients using logistic regression models.

Results:

Our study subjects comprised 63 RA patients (mean age, 73.8 years; 86.5% female) and 30 OA patients (mean age, 75.8 years; 82.3% female). The WST and RSST revealed that RA patients had a significantly higher prevalence of dysphagia than OA patients (23.8% vs 6.7%, p<0.05). While RA patients with dysphagia (n=15) were significantly older and had a longer disease duration than the OA patients, we observed no difference in disease activity or administrated drugs. Of the RA patients with dysphagia, 60% reported no previous episodes of aspiration. Increasing age (odds ratio (OR) 3.21, 95% confidence interval (CI) 1.06-4.56), cervical range of motion limitations (OR 3.14, 95% CI 1.02-7.24), opening disorder of the jaw (OR 2.26, 95% CI 1.12-4.86), and decreased grip strength (OR 1.96, 95% CI 1.01-4.15) were identified as factors related to the presence of dysphagia. Coexistence of Sjogren’s syndrome did not significantly affect the prevalence of dysphagia.

Conclusion:

Dysphagia was more prevalent among RA patients than in OA patients, suggesting an association with temporomandibular involvement, cervical disorder, and muscle weakness. Subclinical dysphagia should be assessed and monitored carefully in the clinical course of elderly patients with RA.

References:

[1] KW Altman et al. Consequence of dysphagia in the hospitalized patient: impact on prognosis and hospital resources. Arch Otolaryngol Head Neck Surg. 2010 Aug; 136 (8):784-9.

[2] Gilheaney Ó et al. The Prevalence of Oropharyngeal Dysphagia in Adults Presenting with Temporomandibular Disorders Associated with Rheumatoid Arthritis: A Systematic Review and Meta-analysis. Dysphagia. 2017 Oct; 32 (5):587-600.

[3] Mugii N et al. Oropharyngeal Dysphagia in Dermatomyositis: Associations with Clinical and Laboratory Features Including Autoantibodies. PLoS One. 2016 May 11;11 (5):e0154746.

Disclosure of Interests:

None declared

A Diagnostic Loop-Mediated Isothermal Amplification Method to Distinguish Helicoverpa armigera (Lepidoptera: Noctuidae) From Other Related Species in the New World

Helicoverpa armigera (Hübner) is a notorious agricultural pest native to the Old World. Recently, its invasion into South and Central America has become a serious problem in the New World. The rapid detection of invasive pests is essential to eradicate them and prevent establishment. However, an extremely similar species, H. zea (Boddie) distributed in the New World makes identification difficult. Helicoverpa armigera and H. zea have only minor differences in male genitalia to separate them morphologically. Both species are attracted to the same pheromone lure, and it takes considerable time and effort to identify them from bulk samples obtained during trap monitoring. Although several molecular approaches based on PCR have been reported, these methods require expensive equipment and are unsuitable for onsite diagnostics. Here, we developed a rapid and convenient diagnostic method based on the loop-mediated isothermal amplification to distinguish H. armigera from related species: H. zea, H. assulta (Guenée), H. punctigera (Wallengren), and Chloridea virescens (Fabricius). The diagnostic method makes it possible to detect H. armigera within 90 min only using simple equipment. The method also worked with mixed DNA templates containing excess DNA from H. zea at the ratio of 1:999 (H. armigera:H. zea). This method can be an effective tool for onsite diagnostics during monitoring surveys for invasive H. armigera.

Observational Evidence for Stochastic Shock Drift Acceleration of Electrons at the Earth's Bow Shock

The first-order Fermi acceleration of electrons requires an injection of electrons into a mildly relativistic energy range. However, the mechanism of injection has remained a puzzle both in theory and observation. We present direct evidence for a novel stochastic shock drift acceleration theory for the injection obtained with Magnetospheric Multiscale observations at the Earth's bow shock. The theoretical model can explain electron acceleration to mildly relativistic energies at high-speed astrophysical shocks, which may provide a solution to the long-standing issue of electron injection.

P3638Triglyceride deposite cardiomyovasculopathy latency in population with coronary artery disease

Background

Triglyceride deposit cardiomyovasculopathy (TGCV) is a novel clinical concept found among Japanese cardiac transplant recipients in 2008 that the abnormal intracellular triglyceride (TG) metabolism results in the ectopic accumulation of TG in vascular smooth muscle cells and cardiomyocytes, leading to diffuse narrowing coronary artery disease (CAD) and heart failure. TGCV is estimated to affect almost forty to fifty-thousand people in Japan, but there is no real-world date about the prevalence or latency.

Purpose

To evaluate TGCV latency in population with CAD, especially requiring urgent coronary angiography as Study 1, and chronic hemodialysis as Study 2.

Methods

This is multicenter retrospective estimation consisting of two studies.

Study 1) From 2012 to 2017, consecutive 400 patients of unstable angina or acute myocardial infarction who underwent urgent coronary angiography (CAG) and following iodine-123-β-methyliodophenyl-pentadecanoic acid (BMIPP) scintigraphy, a tracer for the diagnosis of TGCV, were enrolled.

Study 2) From 2011 to 2017, 88 chronic hemodialysis patients who underwent planed CAG and BMIPP scintigraphy for detection of ischemic heart disease were enrolled.

TGCV was diagnosed based on the latest diagnostic criteria for TGCV. The criteria include two major items (2 points each: BMIPP scintigraphy Wash-Out Rare <10%, Diffuse narrowing coronary arteries) and two minor items (1 point each: Jordans' anomaly in peripheral blood smear, Diabetes). Four points or more and three points indicated definite and probable TGCV, respectively. Only Items other than Jordans' anomaly were available for the diagnosis of TGCV because of retrospective nature. We evaluated the latent rate of definite and probable TGCV.

Results

Study 1) Figure (left) demonstrates the result of Study 1. Definitive TGCV patients were 14 patients, accounting for 3.5% of total 400 patients, and probable TGCV patients were 39 patients, accounting for 9.8% of all. Total 53 definitive and probable TGCV patients accounted for 13.3% of all. Annual average latency were 3.6±1.7% as definitive, 10.0±5.5% as probable and 13.6±6.6% as definitive and probable TGCV, respectively.

Study 2) Figure (right) demonstrates the result of Study 2. Definitive TGCV patients were 17 patients, accounting for 19.3% of total 88 hemodialysis patients, and probable TGCV patients were 22 patients, accounting for 25.0% of all. Total 39 definitive and probable TGCV patients accounted for 44.3% of all. Annual average latency of definitive TGCV was 19.3±13.4%. Of the 17 definitive TGCV patients, 9 patients were hemodialysis patients with diabetes.

Figure 1

Conclusions

TGCV might be latent with a probability of 3.6±1.7% per year in patients with unstable angina or acute myocardial infarction, and with a probability of 19.3±13.4% per year in chronic hemodialysis patients suspected of ischemic heart disease.

P2688A novel risk factor of stent restenosis after drug-eluting stent implantation; Involvement of triglyceride deposit cardiomyovasculopathy, coronary atherosclerosis with triglyceride deposition

Background

Triglyceride deposit cardiomyovasculopathy (TGCV) is a novel disease concept characterized by the excessive accumulation of triglyceride in cardiomyocytes and vascular smooth muscle cells, leading to coronary artery disease (CAD), heart failure, and arrhythmia. However, it is rarely known whether TGCV contributes to the increased risk of vascular failure after drug eluting stent (DES) implantation.

Purpose

The aim of this study was to evaluate vascular failure after 2nd generation DES implantation in patients with TGCV.

Methods

Among 637 consecutive patients suspected of having CAD who underwent both coronary angiography and iodine-123-β-methyliodophenyl-pentadecanoic acid (BMIPP) scintigraphy between 2010 and 2018, we analyzed the data from 92 patients who met the inclusion criteria (shown in Table and Figure). Ninety-two patients were allocated to the presence (TGCV group, 11 patients) or absence (control group, 81 patients) of TGCV. All of 92 patients were implanted 2nd generation DES and underwent planned follow up coronary angiography. Control patients were diagnosed of diabetes mellitus. Binary restenosis (ISR), defined as angiographic luminal diameter ≥50% by quantitative coronary angiography, target lesion revascularization (TLR), In-stent late loss and restenosis morphology were assessed in 23 stents of TGCV group and 120 stents of control group.

Results

There were no significant differences in baseline characteristics between the two groups except for the prevalence of hypertension. In-stent late loss was greater in TGCV than in control (0.45 (−0.04 to 3.33) vs. 0.15 (−0.18 to 2.75), p=0.ehz748.10067), resulting in greater incidence of ISR and TLR in TGCV than in control (34.8% vs. 10.0%, p=0.0017; 21.7% vs. 6.7%, p=0.021, respectively). On multivariable logistic regression analysis, TGCV was found to be a significant and independent predictor for ISR after 2nd generation DES implantation. Regarding restenosis morphology, diffuse and occlusive pattern of ISR, were more frequently observed in TGCV than control (87.5% and 33.3%, Fisher's exact test p=0.028).

Table 1.The 4th edition diagnostic criteria for TGCV Items Clinical findings 2 points I) BMIPP scintigraphy Wash-Out Rare <10% II) Diffuse narrowng coronary arteries 1 point III) Jordans anomaly in peripheral blood smear IV) Diabetes Decision 4 points or more → Definite TGCV

Figure 1

Conclusion

Patients with TGCV showed the greater incidence of vascular failure even after 2nd generation DES implantation, contributing to the novel risk factor for coronary intervention even in the 2nd DES era.

P5628Resolution of incomplete stent apposition in the early phase after stent implantation: serial optical coherence tomography analyses at 2-week and 4-month

Background

Previous optical coherence tomography (OCT) study demonstrated that the incomplete stent apposition (ISA) distance <355 μm immediately after an index procedure was the corresponding cut-off point for predicting the resolution of ISA at 8–12 months follow-up in the second-generation DES. However, the natural course of acute ISA in the earlier phase remains unknown. The aim of the present study is to evaluate the natural course of acute ISA in the early phase after second-generation everolimus-eluting stent (EES) using serial OCT analyses at 2-week and 4-month.

Methods

From the population of the ACS-OCT trial, we identified a total of 45 patients who successfully underwent serial OCT examinations at post-stenting, 2-week follow-up, and 4-month follow-up. The presence of ISA was assessed in the OCT images, and ISA distance was measured within the stented segment. The target site for OCT analysis was the cross-section at the proximal edge of implanted stent. Serial OCT images at post-stenting, 2-week follow-up and 4-month follow-up were reviewed side by side on the screen, and maximum ISA distance and cross-sectional ISA area were measured.

Results

Incomplete stent apposition was observed in all EES at post-stenting, and it was persistent in 37.8% at 2-week follow-up and 11.1% at 4-month follow-up. Maximum ISA distance was significantly decreased over time (post-stenting, 144±150mm; 2-week follow-up, 88±146mm; 4-month follow-up, 34±111mm). Receiver-operating curve analysis identified that the best cut-off value of OCT-estimated ISA distance at post-stenting for predicting persistent ISA at 2-week follow-up and 4-month follow-up was >140μm and >215μm, respectively.

ROC curve analysis

Conclusion

ISA distance at post-stenting is an useful predictor for the resolution of ISA in the early phase after EES implantation.

2421Immunosuppressive therapy and prognosis in biopsy-proven fulminant lymphocytic myocarditis requiring veno-arterial extracorporeal membranous oxygenation support

Background

Fulminant myocarditis is one of the fatal diseases for which effective management has not yet been established. Immunosuppressive therapy (IST) using corticosteroid has been actively applied to giant cell or eosinophilic myocarditis, there is no consensus on the efficacy of lymphocytic myocarditis, which is suspected of involving viral infection. Actually, IST for lymphocytic myocarditis is not recommended in the European Society of Cardiology guidelines, but in the Japanese Circulation Society guidelines, it is approved for use in refractory cases in the absence of curative therapy for myocarditis established.

Purpose

The purpose of this study was to explore the potential efficacy of immunosuppressive therapy on acute phase in fulminant lymphocytic myocarditis (FLM) requiring veno-arterial extracorporeal membranous oxygenation (VA-ECMO) support.

Method

We conducted CHANGE-PUMP study that was retrospectively enrolled 99 patients with fulminant myocarditis required VA-ECMO support in the Tokai area (central part of Japan) for the past 20 years. Lymphocytic myocarditis was defined by pathological category. Patients were divided into two groups depending on whether IST using corticosteroid was performed in the clinical course. Results: Sixty-six patients were pathologically diagnosed as fulminant myocarditis by endomyocardial biopsy, of which only 49 patients were FLM. IST were indicated in 8 (16%) out of 49 patients of FLM (IST group; n=8, non-IST group; n=41). Kaplan-Meier survival analysis showed a lower survival rate in the IST group than in the non-IST group (p=0.073). However, in all cases, based on our guidelines, IST was initiated after becoming refractory to MCS treatment.

Immunosupressive therapy and prognosis

Conclusion

In the retrospective analysis, biopsy-proven FLM patients with IST required VA-ECMO support had low survival rates. However, the timing of IST introduction was late and concerned. In the present era when advanced mechanical support appears and the survival rate of fulminant myocarditis is expected to improve, a multicenter prospective study is needed to establish an indication of IST in the acute phase of fulminant myocarditis.

P5633Diagnostic impact of resting full-cycle ratio as newly developed non-hyperemic indices for physiological lesion assessment

Background

Although fractional flow reserve (FFR) is a gold standard method to evaluate functional lesion severity in the catheterization laboratory, the need of hyperemic condition limits the widespread adoption of FFR. Recently, the resting full-cycle ratio (RFR) which was newly developed resting indices was launched. It is unclear whether RFR as resting condition could assess physiological lesion severity of coronary artery stenosis. The aim of this study was to evaluate the diagnostic impact of RFR compared to FFR in entire range of coronary artery stenosis.

Method

A total of 53 patients with 70 lesions were enrolled in this study. The RFR was measured after adequately waiting for stable condition, while FFR was measured after intravenous administration of ATP (180mcg/kg/min). Lesions with FFR ≤0.80 were considered functionally significant coronary artery stenosis.

Results

In all lesions, reference diameter, diameter stenosis, lesion length, RFR, and FFR were 3.3±0.8mm, 44±12%, 14.6±7.2mm, 0.90±0.11, and 0.83±0.11, respectively. Functional significance was observed in 24 lesions (34%) of all lesions. The RFR showed a significant correlation with FFR (y = 0.800x + 0.239, R = 0.817, p<0.001). The Bland-Altman plot demonstrated a good agreement with a mean difference of 0.07 and a standard deviation of 0.06 between RFR and FFR across entire range of coronary artery stenosis. ROC curve analysis showed an excellent accuracy of RFR cut-off of ≤0.90 in predicting FFR ≤0.80 which had 78% sensitivity and 87% specificity (AUC 0.87, diagnostic accuracy 84%).

Conclusion

The RFR as newly resting indices is reliable to the assessment of functional lesion severity. This physiology-based approach may be a possible alternative method for FFR measurements in daily practice.