Diagnostic value of myocardial perfusion CT to detect coexisting microvascular dysfunction in patients with obstructive epicardial coronary disease

Background

The usefulness of computed tomography myocardial perfusion (CTP) to assess hemodynamically significant coronary artery lesions has been previously reported. However, the diagnostic value of quantitative evaluation of regional absolute coronary flow by CTP to detect microvascular dysfunction remains unknown.

Purpose

The aim of study is to assess the diagnostic value of preprocedural CTP to detect coexisting microvascular dysfunction with functionally significant epicardial stenosis in patients with chronic coronary syndromes.

Methods and results

Thirty-three chronic coronary syndrome patients with de novo single functionally significant stenosis (Fractional flow reserve [FFR]<0.80) who underwent noncomplicated PCI were investigated. In CTP analysis, regional myocardial blood flow (MBF) at rest (rest-MBF) and hyperemia (hyperemic-MBF) were evaluated semi-automatically. Clinical characteristics, pressure-temperature sensor-chipped wire-based information and CTP findings were compared between groups with and without microvascular dysfunction defined by the index of microcirculatory resistance (IMR) (IMR≥25, n=17, IMR<25, n=16, respectively).

The determinants of coexistence of microvascular dysfunction and functional epicardial stenosis were determined. In invasive wire-based analysis, FFR, coronary flow reserve (CFRwire) and IMR were 0.68 (0.57–0.72), 1.61 (1.00–1.98), and 26.7 (19.3–39.4) respectively.

In CTP analysis, rest and hyperemic-MBF and CFR derived from CTP (CFRCTP; calculated as hyperemic-MBF/rest-MBF) were 2.00 (1.31–2.35) ml/min/g, 4.03 (2.11–5.44) ml/min/g, and 2.09 (1.49–2.09) respectively.

In the lesions with IMR>25, hyperemic-MBF was significantly lower than that in IMR<25 (3.42 [1.89–4.34] vs 4.50 [3.44–5.99], p=0.031), although there was no significant difference in regional rest-MBF and CFRCTP (1.75 [1.31–2.24] vs 2.05 [1.35–2.46], p=0.439, and 1.83 [1.21–2.11] vs 2.61 [1.91–2.91], p=0.101 respectively). Receiver operating characteristic curve analysis of hyperemic-MBF detecting IMR>25 showed area under the curve of 0.72 (0.54–0.90), sensitivity of 47% and specificity of 94%.

Conclusion

Quantitative assessment of absolute coronary flow by CTP may help detect coexisting microvascular dysfunction in patients with significant epicardial stenotic lesions.

Funding Acknowledgement

Type of funding source: None

Prognostic value of fat attenuation index of pericoronary adipose tissue surrounding left anterior descending artery on coronary computed tomography angiography

Background

Recent studies reported the association between elevated fat attenuation index (FAI) of pericoronary adipose tissue (PCAT) on coronary computed tomography angiography (CTA) and worse cardiac outcomes.

Purpose

We investigated the prognostic value of increased FAI-defined coronary inflammation status in patients with coronary artery disease.

Methods

Three-hundred fifty-eight patients (127 acute coronary syndromes [ACS], 231 stable coronary artery disease) with left anterior descending artery (LAD) as a culprit vessel who underwent coronary CTA were retrospectively studied. The FAI defined as the mean CT attenuation value of PCAT (−190 to −30 Hounsfield Unit [HU]) was measured at the proximal 40-mm segment of LAD. All subjects were divided into two groups according to the median value of FAI in the LAD. The association between the incidence of major adverse cardiac events (MACE) including all-cause death, myocardial infarction, heart failure, target and non-target vessel revascularization were evaluated.

Results

In a total of 358 patients, median FAI values surrounding the LAD was −71.46 (interquartile range, −77.10 to −66.34) HU. Thirty-eight patients (10.6%) experienced MACE during the follow-up period (median, 818 days). Kaplan-Meier analysis revealed that high FAI-LAD (>−71.46 HU [median]) was significantly associated with the incidence of MACE (log-rank test, chi-square = 4.183, P=0.041) (Figure).

Conclusions

In patients with coronary artery disease with culprit LAD lesions, elevated FAI of PCAT surrounding the LAD was associated with worse clinical outcomes. Assessment of FAI may have a potential for potential for non-invasive risk-stratification by coronary CTA.

Kaplan-Meier analysis for MACE

Funding Acknowledgement

Type of funding source: None

Impact of neoatherosclerosis observed at very late phase after coronary stent implantation on subsequent adverse events

Background

Despite the reduction in late thrombotic events with newer generation coronary stents, late stent failure remains a concern following stent implantation. Neoatherosclerosis (NA) is a cause of in-stent restenosis and acute thrombotic occlusion originating from the stented segment by disruption of the in-stent atheroma. Although the clinical impact of NA at 1 year has been reported, clinical significance of NA observed at very later phase remains to be determined. We sought to investigate the association between optical coherence tomography (OCT) findings at very late phase after stenting and subsequent clinical outcomes.

Methods

A total of 195 patients with 316 stents (including 74 bare metal stents, 48 first-generation DES, and 194 second-generation DES) without stent failure who underwent OCT examination at >3 years (4.9 [3.9- 5.8] years) after stent implantation according to the prespecified protocol were investigated. OCT analysis included the presence of lipid-laden neointima, macrophage, malapposition, thrombus, and plaque rupture within the stents. NA was defined as having lipid-laden neointima. The criteria for the diagnosis of NA were signal-poor region in continuous flames, lipid length longer than 0.3 mm, and invisible stent strut at NA site. Quantitative OCT measurement included lipid length (LL), lipid arc, minimum lumen area (MLA) at the stented segment and minimum stent area (MSA). Major adverse cardiac events (MACE) including all-cause death, non-fatal myocardial infarction, and clinically driven revascularization were assessed. MACE-free survival rate was compared between patients with stent showing NA (NA group) and those without NA (non-NA group). Furthermore, in per-stent basis analysis, stent failure including remote revascularization and stent thrombosis of the stent after follow-up OCT examination was assessed.

Results

NA was identified in 50 stents (15.8%) in 38 patients (19.5%). During the median follow-up period of 2.1 [1.0- 2.8] years after OCT examination, 15 MACEs (7.7%) were captured in the total cohort, of which stent failure was observed in 5 stents (5/316, 1.6%). In patient-based analysis, patients with NA had more frequent MACE than those without (18.0% vs 5.1%, p=0.01). Kaplan-Meier analysis revealed that significantly higher MACE rate was detected in NA group than in non-NA group (χ2=5.4, Log-rank p=0.02). In stent-based analysis, NA stents had more frequent stent failure than those without (8.0% vs 0.4%, p=0.002)

Conclusions

NA observed by OCT at >3 years after implantation were associated with subsequent worse clinical outcomes in both patient and stent-based analysis. NA at the very late phase after stenting might be the therapeutic target of secondary prevention and OCT examination at very late phase after stenting may help identify high risk patients of subsequent MACE.

Funding Acknowledgement

Type of funding source: None

Prognostic value of coronary flow capacity assessed by coronary sinus flow obtained by phase contrast cine-magnetic resonance imaging in patients with acute coronary syndrome

Background

The concept of coronary flow capacity (CFC) originated from positron emission tomography has been reported to provide prognostic information. Phase contrast cine-magnetic resonance imaging (PC-CMR) of the coronary sinus (CS) is a promising approach for quantifying global coronary sinus flow (CSF) and global coronary flow reserve (g-CFR) without the need for ionizing radiation, radioactive tracers, or intravascular catheterization.

Purpose

We evaluated the prognostic value of postprocedural CFC by quantifying CSF using PC-CMR in patients with acute coronary syndrome (ACS) treated with primary or urgent percutaneous coronary intervention (PCI).

Methods

This study prospectively but nonconsecutively enrolled 569 ACS patients who underwent uncomplicated primary (for ST-segment elevation myocardial infarction (STEMI)) or urgent PCI within 48 hours of symptom onset (for non-ST elevation acute coronary syndrome (NSTE-ACS)). Breath-hold PC-CMR images of CS were acquired to assess absolute CSF at rest and during maximum hyperemia within 30 days after culprit lesion PCI and revascularization of functionally significant non-culprit lesions. The entire cohort was stratified by the CFC according to the thresholds of hyperemic CSF and g-CFR. Impaired CFC was defined as a severely-reduced CFC in the present study. The association of CFC and baseline clinical characteristics with major adverse cardiac events (all-cause death, nonfatal myocardial infarction, hospitalization for congestive heart failure or stroke) was investigated.

Results

In the final analysis of 502 patients (Male 417 (83.1%), mean age was 67 [58, 73]) and 310 patients (82.3%) with STEMI and 192 patients (38.2%) with NSTE-ACS were studied. In a total cohort, rest and maximal hyperemic CSF and corrected G-CFR were 0.93 [0.68, 1.24] ml/min/g, 2.08 [1.44, 2.77] ml/min/g, and 2.21 [1.58, 3.05], respectively. During a median follow-up of 28 months, MACE occurred in 53 patients (all-cause death: 19, nonfatal myocardial infarction: 16, late revascularization: 59, hospitalization for congestive heart failure: 9, stroke: 9). Cox proportional hazards analysis showed that corrected G-CFR and impaired CFC were both independent predictors of MACE. (hazard ratio (HR), 0.61, 95% confidence interval (CI): 0.45–0.82, p=0.001; HR, 3.51, 95% CI: 1.79–6.86, p≤0.001, respectively). Cardiac event-free survival was significantly worse in patients with impaired CFC (log-rank χ2=22.9, P<0.001). Net reclassification index (NRI) and integrated discrimination improvement (IDI) were both significantly improved when impaired CFC was added to the clinical risk model for predicting MACE.

Conclusions

In ACS patients successfully revascularized with primary or urgent PCI, CFC categorization stratified by noninvasive PC-CMR provided significant prognostic information independent of infarction size, conventional risk factors and g-CFR.

Funding Acknowledgement

Type of funding source: None

Association between near-infrared spectroscopy defined lipid rich plaque and pericoronary adipose tissue inflammation on computed tomography angiography

Background

A recent study has shown that lipid-rich plaque (LRP) detected by near-infrared spectroscopy (NIRS) is a significant predictor of future adverse events. Pericoronary adipose tissue inflammation (FAI; fat attenuation index) evaluated by computed tomography angiography (CTA) has also been reported to be linked with cardiac events. The relationship between NIRS-defined LRP and FAI remains to be determined.

Methods

A total of 82 de novo culprit lesions in 82 patients with chronic coronary syndromes (CCS) who underwent perprocedural CTA and NIRS was retrospectively studied. FAI was assessed by the crude analysis of the mean CT attenuation value (−190 to −30 Hounsfield units; higher values indicating inflammation) of pericoronary adipose tissue. Plaque morphology was assessed by coronary CTA and grey-scale intravascular ultrasound (IVUS). NIRS-defined LRP was defined as a maximum lipid core burden index (LCBI) in 4 mm ≥400. Relationship between NIRS-defined LRP, CTA/grey-scale IVUS findings, and FAI was assessed. Univariate and multivariate logistic regression analyses were performed to determine the predictors for NIRS-derived LRP.

Results

NIRS-defined LRP was observed in 35 (42.6%) patients. Maximum LCBI showed modest correlations both with FAI (r=0.29, p-value=0.007) and CT-derived remodeling index (r=0.51, p<0.001). Receiver operating characteristic (ROC) curve analysis revealed that the best cut-off values of FAI and CT-derived remodeling index for predicting NIRS-defined LRP were −70.7 (AUC: 0.65, 95% CI: 0.53–0.71, P<0.05) and 1.11 (AUC: 0.74, 95% CI: 0.63–0.86, P<0.01), respectively. Multivariate logistic regression analysis showed FAI ≥−70.7 (odds ratio [OR]: 4.27; 95% CI: 1.28–14.3; p-value = 0.02) and CT-derived remodeling index (OR: 10.7; 95% CI: 2.99–32.2; p-value <0.001) were independent predictors of the presence of NIRS-defined LRP, whereas there was no statistically significant and independent predictor of IVUS-derived factors for NIRS-defined LRP. When stratified according to the presence or absence of FAI ≥−70.7 and CT-derived remodeling index ≥1.11, 93% of the lesions showed NIRS-derived LRP when both factors were present, and NIRS-derived LRP was safely ruled out (88%) when both factors were absent.

Conclusions

FAI of the culprit lesion in CCS was an independent predictor of NIRS-defined LRP, supporting the notion that local pericoronary adipose tissue inflammation may correlate to the presence of LRP. Comprehensive assessment of coronary CTA including FAI evaluation may provide a highly accurate information with high sensitivity and specificity for identifying high risk lesions potentially leading to future cardiac events.

Funding Acknowledgement

Type of funding source: None

Clinical significance of the periaortic adipose tissue inflammation in patients with abdominal aortic aneurysms

Background

Recent studies have reported the association between periaortic adipose tissue volumes identified by multi-detector computed tomography (MDCT) and the periaortic adipose tissue inflammation (PATI) identified by positron emission tomography, which may suggest the link between perivascular inflammation and aortic dilation. However, clinical significance of the PATI identified by MDCT remains elusive in patients with asymptomatic abdominal aortic aneurysm (AAA).

Methods

A total of 77 patients with AAA (diameter >30mm) who underwent the initial and follow-up MDCT examinations were studied retrospectively. PATI was assessed by the crude analysis of the mean CT attenuation value (−190 to −30 Hounsfield units; higher values indicating inflammation). The AAA progression (AP) was defined as the growth of AAA diameter >5.0mm/year from the initial to follow-up. Univariate and multivariate logistic regression analysis were performed to determine the predictors for AP.

Results

AP was observed in 19 (24.7%) patient, the median initial AAA diameter was 38.9 (32.7–42.9) mm, and the median progression of AAA diameter was 3.1 (1.5–4.9) mm/year. The initial AAA diameter (odds ratio [OR]: 1.16; 95% confidence interval [CI]: 1.05–1.28; p-value=0.001) and the initial PATI (OR: 1.12; 95% CI: 1.05–1.20; p-value=0.004) were independent predictors of AP. PATI of −71.08 at initial MDCT and the initial AAA diameter of 37.7mm were the best cut-off value to predict AP. Receiver operating characteristic curve analysis revealed that the best cut-off values of PATI at initial MDCT and the initial AAA diameter for predicting AP were −71.08 (AUC: 0.68, 95% CI: 0.50–0.82) and 37.7 (AUC: 0.71, 95% CI: 0.59–0.84), respectively. Addition of the initial AAA diameter to PATI at initial MDCT significantly increased the accuracy for discriminating AP (net reclassification improvement; 95% CI: 0.67 [0.17–1.17]; p-value = 0.007, integrated discrimination improvement; 95% CI: 0.14 [0.04–0.24]; p-value =0.007).

Conclusions

PATI was an independent and significant predictor of aortic dilation, supporting the notion that local adipose tissue inflammation may contribute to aortic remodeling. Comprehensive assessment of MDCT including PATI evaluation may provide a highly accurate information for identifying high risk lesions potentially leading to future AAA rupture.

Funding Acknowledgement

Type of funding source: None

Impact of pericoronary inflammation assessed by coronary computed tomography angiography on the progression of aortic valve calcification

Background

Aortic valve calcification (AVC) has been known as an independent predictor for adverse cardiovascular events and all-cause mortality. Previous studies demonstrated that AVC was associated with aortic valve inflammation and atherosclerosis. However, the relationship between the progression of AVC and pericoronary inflammation remains undetermined.

Purpose

The purpose of this study was to evaluate the impact of the pericoronary inflammation on the progression of AVC.

Methods

A total of 107 patients with suspected or known chronic coronary syndromes who underwent clinically indicated serial 320-slice coronary computed tomography angiography (CTA) at Tsuchiura Kyodo General Hospital from January 2011 to June 2019 were retrospectively studied. Pericoronary inflammation was assessed by pericoronary adipose tissue attenuation (PCATA) defined as the mean CT attenuation value of PCATA (−190 to −30 Hounsfield units [HU]) on proximal 40 mm segments of coronary arteries. AVC was quantified by Agatston score on CTA. The mean aortic attenuation (HU Aorta) and the standard deviation (SD) in the region of interest at the level of the sinotubular junction was measured. AVC was defined as the threshold for calcium detection (mean HU Aorta + 2SD). AVC index was calculated as follows: (follow-up/baseline) AVC divided by follow-up period. AVC progression was defined as newly-developed AVC at follow-up or an increased AVC index during follow-up. All patients were divided into two groups according to the presence or absence of AVC progression, and clinical characteristics and CT findings were compared between these two groups.

Results

AVC progression was observed in 26 patients (24.3%) between 2 serial CT examinations (median, 34 months). There was no significant difference in age, gender and the prevalence of other cardiovascular risk factors between the 2 groups. Patients in AVC progression group were associated with higher prevalence of elevated PCATA-LAD, higher LV mass index at baseline and the initial AVC presence. Receiver-operating characteristic curve analysis revealed that the optimal cut off value of PCATA-LAD for predicting AVC progression was −68.26 HU (area under the curve 0.605; 95% confidence interval [CI], 0.465–0.745). Multivariable logistic regression analysis revealed that baseline PCATA-LAD ≥−68.26 HU (odds ratio [OR], 3.12; 95% CI, 1.04–9.35, p=0.042) and the presence of baseline positive AVC (OR, 6.84; 95% CI, 2.34–20.0, p=0.0004) were independent predictors of AVC progression.

Conclusions

The increased pericoronary inflammation and the presence of AVC may help identify patients with high risk for future AVC progression.

Funding Acknowledgement

Type of funding source: None

Functional characterization of an aldose reductase (bmALD1) obtained from the silkworm Bombyx mori

We describe a new member of the aldo-keto reductase (AKR) superfamily in the silkworm Bombyx mori. On the basis of its amino acid sequence and phylogenetic tree, this AKR belongs to the AKR1B family and has been designated as bmALD1. In the current study, recombinant bmALD1 was overexpressed, purified to homogeneity and kinetically characterized. We discovered that bmALD1 uses NADPH as a coenzyme to reduce carbonyl compounds such as DL-glyceraldehyde, glucose and 2-nonenal. No NADH-dependent activity was detected. To the best of our knowledge, bmALD1 is only the third AKR characterized in silkworm which, given its substrate specificity, could play a major role in glucose metabolism and antioxidant reactions. Our data provide an increased understanding of insect AKR function.

Types of grocery stores and demographic and household factors in Japanese provincial area

Background

Neighborhood grocery stores, such as supermarkets (SM) and convenience stores (CVS), have received attention as a determinant of a food purchase behavior. Previous studies reported that grocery store entry or closure was associated with regional populations. This study examines the association of types of SM (i.e. cross-regional, local, or small chain stores), CVS, and household demographics in the cities, towns and villages (having its own incorporated government) in Hiroshima and Okayama Prefectures, Japan.

Methods

We hypothesized that the entry and closure of SM, CVS are associated with the regional population and type of family household from interview surveys with supermarket and wholesale operators. We collected data on SM and CVS from Large-Scale Retail Store Data in Japan, while data on demographics and households were collected from the census. Data sets from 59 municipalities (city, town, ward, and village) and 49 SM chains (498 stores) and 8 CVS chains (1235 stores) were analyzed using multiple regression analysis.

Results

Some household factors showed significant associations with the number of SM and CVS at the municipality level. Those municipalities with a greater number of extended families and single households had significantly more “cross-regional” as well as “local chain SM” stores. Those municipalities with more nuclear families had significantly more “small chain SM” and fewer “local chain SM” stores. Those municipalities with more single households had significantly fewer SM stores.

Conclusions

In these prefectures, population declining and single household increasing are expected over the coming decades. If no political interventions are allowed on this issue, some of “food desert” may emerge for the hundreds of thousands people living in these areas; elderly people may not get fresh vegetables in their neighborhood, and young parents will have to drive for hours to “cross-regional SM” to buy fresh milk for their children.

Key messages

Supermarkets and convenience stores are determinant of a food purchase behavior. The association of the number of types of SM, CVS, and demographic and household factors.

SAT0119 PARADOXICAL NEUTROPHIL ACTIVATION BY ANTI-IL6 THERAPY: TRANSCRIPTOME ANALYSIS SHOWS A RATIONALE FOR DERMATOLOGICAL ADVERSE REACTIONS AND DECREASED NEUTROPHIL COUNTS AFTER TOCILIZUMAB TREATMENT

Background:

Skin rashes as a side effect of Tocilizumab therapy (TCZ- Tx) has not been paid much attention, because the incidence was only 1~2% in the drug information sheets. However, we experienced several RA cases with development of various skin rashes associated with neutrophil activation after TCZ-Tx. On the other hand, it is well known that the neutrophil counts in peripheral blood decreases after TCZ-Tx, whereas it does not affect the rate of serious infections. The detailed mechanism is still unclear.

Objectives:

To detect the characteristics of the changes in gene expressions of peripheral blood associated with TCZ-Tx and the development of skin rashes as its side effect.

Methods:

Total of 14 RA patients with TCZ-Tx were included. Among them, 4 patients developed TCZ-related rashes (group S) and 10 patients did not show any side effects (group C). Peripheral whole blood at just before (pre) and 3 months after (post) TCZ-Tx from each patient were subjected to the analysis. Total RNAs were extracted with PAXgene miRNA kit and analyzed with next-generation sequencing. First, group C was investigated for the normal response to TCZ-Tx. Differentially expressed genes (DEGs) were selected by paired comparison (post vs. pre). And then, enrichment analysis using gene ontology (GO) terms were performed. Second, to explore the characteristics of group S, all expressed genes in 14 cases at just before TCZ-Tx were subjected to a hierarchical clustering analysis. The DEGs (group S vs. C and post vs. pre) were also investigated with weighted gene co-expression network analysis (WGCNA) and GO analysis. Meanwhile, the total eigengene expressions of the important modules identified by WGCNA in each cases were also calculated.

Results:

Surprisingly, 8 out of the top 10 enriched GO terms in the up-regulated genes were relevant to leukocyte activation such as ‘neutrophil migration” by the analysis of DEGs (post vs. pre) in group C. The cluster analysis of ‘pre’ genes confirmed that the patterns of gene expression between group S and C was different. WGCNA analysis of DEGs (group S vs. C) revealed that genes related to acute inflammation such as ‘leukocyte mediated immunity’ were activated in group S. Interestingly, it was not correlated with disease activity score (DAS) of RA. By the analysis of DEGs (post vs. pre) of upregulated genes, we found that the total eigengene expressions of the module enriched with genes related to ‘cell adhesion’ or ‘leukocyte migration’ were significantly increased in all cases of group S.

Conclusion:

This is the first evidence that the genes associated with neutrophil migration is significantly activated after TCZ-Tx. It is noteworthy that the gene activation was observed in cases without any side effects. The decreased neutrophil counts in peripheral blood have been known after initiation of TCZ-Tx, which did not affect the rate of serious infections. Recently, It was reported that TCZ affects neutrophil trafficking to the bone marrow1). Our findings will provide a rationale for its cause. On the other hand, we experienced several RA cases with development of various skin rashes associated with neutrophil activation after TCZ-Tx. However, majority of patients do not develop the side effect, even though genes related to ‘neutrophil migration’ are activated. In group S, our findings indicate that the genes related to ‘leukocyte mediated immunity’ was already activated at the initiation of treatment without correlating to DAS of RA, furthermore, the gene upregulation related to ‘leukocyte migration’ was more prominent after TCZ-Tx. Although it is difficult to predict the patients developing skin rashes before TCZ-Tx, we do not recommend to use TCZ for the patients with neutrophilic dermatosis which is often associated with RA.

References: :

[1]Lok LSCet al.,Eur J Clin Invest. 47(10):736-745 (2017).

Disclosure of Interests: :

Moe Sakamoto: None declared, Akemi Senoh: None declared, Yoshiharu Sato: None declared, Hiroshi Iijima: None declared, Mari Yamaguchi: None declared, Toshie Higuchi: None declared, Yoshinobu Koyama Grant/research support from: Eli-Lilly and Mochida., Speakers bureau: BMS, Ayumi, Chugai, Ono, Mitsubishi Tanabe, Abbvie and Eisai.

Evaluation of an amplicon-based custom gene panel for the diagnosis of hereditary tumors

Genetic testing based on next-generation sequencing (NGS) analysis has recently been used to diagnose hereditary diseases. In this study, we explored the usefulness of our custom amplicon panel that targeted 23 genes related to hereditary tumors given in the American College of Medical Genetics and Genomics recommendations. We applied our custom NGS panel to samples from 12 patients previously diagnosed by Sanger sequencing as having the diseases or diagnosed clinically by meeting the diagnostic criteria in this study. Our gene panel not only successfully identified all variants detected by Sanger sequencing but also identified previously unrecognized variants that resulted in confirmation of the disease, or even in the revision of the diagnosis. For instance, a patient identified with an SDHD gene mutation actually had von Hippel-Lindau (VHL) syndrome, as determined by the presence of a pathogenic VHL gene variant. We also identified false-positive results that were generated by amplification of genome regions that are not intended to be investigated. In conclusion, NGS-based amplicon sequencing is a highly effective method to detect germline variants, as long as they are also carefully reviewed by manual inspection.

155 Fertility of sexed semen in Holstein heifers and cows

Compared with conventional semen, use of sexed semen decreases the conception rate (CR); therefore, it is important to address the factors that lead to sperm damage. Recently, a novel sexed semen technology was developed for improving dairy cattle fertility (Betthauser et al. 2016 J. Dairy Sci. 99 (E-Suppl. 1), 534). However, there are few reports about the fertility of this novel sexed semen in dairy cattle in Japan. The objective of this study was to compare the CR of traditional sorting semen (S1: flow cytometry/cell sorting) and the novel sexed semen (S2: SexcelTM, ABS Global Inc.) in Holstein heifers and cows in Japan. The CR for the first insemination was obtained from 391 Holstein cows and 148 heifers (10.7-17.8 months old) from 14 dairy farms in Hokkaido from June 2017 to April 2019. Semen used for AI was collected from six bulls and packaged into 0.25-mL straws and frozen. Cows inseminated with conventional frozen semen (S3: unsexed semen in 0.5-mL straws) were used as controls. Calving data were collected from 123 cows and 69 heifers that had calved between January 2018 and May 2019. The diagnosis of pregnancy was confirmed using ultrasonography between 30 and 45 days after insemination. The CR and sex ratio were analysed using chi-square test. The average parity number was 1.9±1.1, and average days open was 84.9±20.4 days. The average interval between calving and the first service was 86.2±20.3 days. The average milk yield (at 305 days) was 12 195±1595 kg. All of the animals were inseminated after the onset of standing heat or removal of the tail chalk of natural heats and oestrus and ovulation synchronisation programmes on the farm. Conception rates of heifers of the first service of S1 (n=54) and S2 (n=94) were 68.5 and 70.2%, respectively. Conception rates of cows of the first service of S1 (n=32), S2 (n=173), and S3 (n=186) were 56.3, 57.8, and 53.8%, respectively. There were no significant differences in CR between these groups (P>0.4). The proportion of female calves produced using S1 (n=61) and S2 (n=57) was 91.8 and 93.0%, respectively, which was significantly more (P<0.01) compared with the 50.0% produced using S3 (n=74). There were no significant differences between S1 and S2 (P>0.8) in terms of the proportion of calves produced. The results of this study demonstrated that the traditional sorting and novel sexed semen (S1 and S2, respectively) did not differ in terms of the first-service CR and produced considerably more female calves than when the conventional semen (S3) was used. Furthermore, these findings indicate that the use of this novel sexed semen could achieve a sex ratio close to 90% female offspring.

P3578Determinants of visual-functional mismatches as assessed by coronary angiography and 3-D angiography-based quantitative flow ratio

Background

Quantitative flow ratio (QFR) is a novel three-dimensional quantitative coronary angiography (QCA)-based computational index that can estimate fractional flow reserve (FFR) without pharmacologically induced hyperemia or the use of a pressure wire.

Purpose

We aimed to evaluate the determinants of visual-functional mismatches between conventional two-dimensional QCA and QFR.

Methods

A total of 504 de novo intermediate-to-severe lesions from 504 patients with stable angina who underwent angiographical and physiological assessments were analyzed. All lesions were divided into four groups based on the significance of visual (QCA-diameter stenosis [DS] >50% and ≤50%) and functional (QFR <0.80 and ≥0.80) stenosis severity. Patient characteristics, angiographic findings, QFR computations, and physiological indices were compared among the four groups.

Results

Among 504 lesions, 153 lesions (30.4%) showed concordantly negative (DS ≤50% and QFR >0.80) and 170 lesions (33.7%) showed concordantly positive (DS >50% and QFR ≤0.80) visual and functional assessments. Among 181 lesions (35.9%) with discordant results, 75 lesions (14.9%) showed a mismatch (DS >50% and QFR >0.80) and 106 lesions (21.0%) showed a reverse mismatch (DS ≤50% and QFR ≤0.80), respectively. Reverse mismatch was associated with smaller reference diameter (odds ratio [OR] 0.561; P=0.036), greater DS (OR 1.039, P=0.013), lower coronary flow reserve (CFR) (OR 0.571, P<0.001, non-diabetes mellitus (OR 2.141, P=0.013) and lower ejection fraction (OR 0.961, P=0.011). Mismatch was associated with smaller DS (OR 0.914, P<0.001), shorter lesion length (OR 0.894, P=0.001), higher CFR (OR 1,633, P<0.001), and lower estimated glomerular filtration rate (OR, 0.968, P=0.001). Lesion location and the index of microcirculatory resistance was not associated with the prevalence of reverse mismatch or mismatch.

Conclusions

There was a high prevalence of visual-functional mismatches between QCA-DS and QFR, and CFR was an important functional factor of mismatches. Our results suggested the difference between predictors of reported visual-functional mismatches of QCA/FFR and those of QCA/QFR.

P2705Hybrid QFR-FFR decision making strategy for revascularization

Background

Measurement of the fractional flow reserve (FFR) has become a standard practice for revascularization decision-making in evaluating the functional significance of angiographically intermediate epicardial coronary stenosis. The quantitative flow ratio (QFR) is a novel method for rapid computational estimation of FFR without pressure wire and vasodilator drugs.

Purpose

Nevertheless, the evidence was shown the clinical better outcome of coronary revascularization stratified by FFR, the adoption of FFR remains low. We hypothesized that combined QFR and FFR hybrid strategy could improve the physiological assessment without pressure wire and drugs.

Methods and results

We performed a post-hocanalysis of 549 vessels with angiographically intermediate stenosis in 549 patients who underwent measurement of FFR. The median FFR and QFR values were 0.81 (0.73–0.87) and 0.79 (0.74–0.87), respectively.The ischemic threshold was defined as 0.80 for both QFR and FFR measures. The diagnostic sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the QFR for predicting an FFR of ≤0.80 were 86.2%, 71.9%, 78.9%, 74.5%, and 84.5%, respectively. The area under the receiver operating characteristic curve using the cut-off threshold of ≤0.80 for the FFR was 0.85 (95% confidence interval [CI], 0.81–0.88) for the QFR.In total, 433 (78.9%) and 116 (21.1%) lesions showed concordant and discordant FFR and QFR functional classifications, respectively. A hybrid QFR-FFR strategy was developed, by allowing deferral when QFR values providing negative predictive value greater than 90% and treat others when QFR values greater than that showing 90% positive predictive value, with adenosine being given only to patients with QFR in between those values. For the FFR cut-off (0.8), an QFR of <0.73 could be used to confirm treatment (PPV of 90.7%), while an QFR value of >0.83 could be used to defer revascularization (NPV of 90.0%). When QFR values fall between 0.73 and 0.84, adenosine is given for hyperemic induction and the FFR cut-off of 0.8 is used to guide revascularization. This hybrid QFR-FFR approach has a 95% agreement with an FFR-only decision making, and 285 lesions (51.9%) would have obviated the need of a pressure wire and adenosine.

Hybrid QFR-FFR strategy

Conclusions

A hybrid QFR-FFR strategy for coronary revascularization could reduce the need of a pressure wire and vasodilator drugs, which may increase the penetration of functional assessment of coronary lesions.

P5619Comparison of different resting physiological indices: are diastolic pressure ratio and resting full-cycle ratio equal?

Background

Previous reports showed all diastolic resting indexes tested were virtually identical to the instantaneous wave-free ratio (iFR). Although RFR has been also reported to be diagnostically equivalent to iFR, no comparisons have been reported about the prevalence and characteristics of discordance in diagnosis between diastolic pressure ratio (dPR) and resting full-cycle ratio (RFR).

Purpose

This study sought to determine the coronary pressure characteristics of lesions classified as discordant between dPR and RFR in angiographically intermediate stenoses.

Methods

We recruited 532 patients with 668 intermediate (angiographically stenosis between 30% to 70% severity) coronary lesions undergoing FFR assessment and analyzed DICOM pressure tracings of resting state (dPR and RFR) using a fully automated off-line software algorithm in a blind fashion. Diagnostic performance of dPR and RFR was evaluated using FFR as a reference. Furthermore, we investigated similarity and difference between dPR and RFR.

Results

Median FFR was 0.81 with an interquartile range of 0.74 to 0.87. RFR was highly correlated to dPR (R2=0.94, p<0.001), with a mean bias of 0.012 (95% limits of agreement −0.008 to 0.031). The diagnostic performance of RFR versus dPR was diagnostic accuracy 95.4%, sensitivity 100.0%, specificity 91.6%, positive predictive value 90.6%, negative predictive value 100.0%). Using the binary cut-off of dPR ≤0.89 as a cut-off value, RFR showed near identical agreement according to ROC curve analysis (AUC: 0.996, 95% CI: 0.994–0.999, p<0.001). Although dPR and RFR demonstrated equivalent performance against FFR ≤0.8 (79.5% vs. 79.3% accuracy; p=0.960; area under the receiver-operating characteristic curve: 0.869 vs. 0.870; p=0.528), RFR disagreed with dPR in 4.6% (31 of 668). When all lesions (668 vessels) were divided into groups according to the concordance and discordance between dPR and RFR: RFR+/dPR+ (298 vessels, n=240), RFR+/dPR– (31 vessels, n=31 patients), RFR-/dPR- (339 vessels, n=259). There was no lesion showing RFR-/dPR+. The prevalence of ischemia was tended to be higher in lesions evaluated by RFR (49.3% vs 44.6%, P=0.100) when using FFR ≤0.80 as a reference standard. An overall significant difference in the prevalence of FFR ≤0.80 and the FFR values were detected among these 3 groups. Furthermore, pairwise comparison also revealed the prevalence of FFR >0.80 and the FFR values were significantly lower in RFR+/dPR– than in RFR-/dPR-, and significantly higher in RFR+/dPR– than in RFR+/dPR+. (P<0.001 and P<0.001, respectively)

Conclusion

Significant difference in FFR values was observed according to dPR/RFR agreement and disagreement. Revascularization decision making might defer according to the resting index used. Compared with RFR, lesions might be more frequently deferred when dPR was used to assess physiological significance.

Acknowledgement/Funding

None

P2704The association between global coronary flow reserve and coronary inflammation assessed by attenuation index on computed tomography in patients with stable angina pectoris

Background

Impaired global coronary flow reserve (G-CFR) is known to predict worse outcomes in patients with coronary artery disease. Phase contrast cine-magnetic resonance imaging (PC-CMR) of the coronary sinus (CS) is a promising approach for quantifying coronary sinus flow (CSF) and G-CFR without the need for ionizing radiation, radioactive tracers, or intravascular catheterization. Although G-CFR impairment is previously reported to be linked with endothelium dysfunction and progression of atherosclerosis, the association of perivascular adipose tissue inflammation with myocardial coronary flow remains to be determined.

Purpose

We evaluated the association between G-CFR by quantifying CSF using PC-CMR and the extent of coronary inflammation evaluated by perivascular adipose tissue inflammatory status using CT to assess if coronary inflammation is linked with G-CFR in patients with stable angina pectoris (SAP) treated with elective percutaneous coronary intervention (PCI).

Methods

The study enrolled 74 SAP patients with single denovo lesion who underwent coronary CT angiography and PC-CMR within 90 days before coronary intervention. Proximal 40-mm segments of all three major epicardial coronary vessels were traced and examined. Coronary inflammation was assessed by the CT fat attenuation index of perivascular adipose tissue (FAI-PVAT) defined as the mean attenuation of the perivascular adipose tissue (−190 to −30 Hounsfield units (HU)) in a layer of tissue within a radial distance from the outer coronary artery wall equal to the diameter of the vessel. CMR images were also acquired to assess absolute CSF at rest and during maximum hyperemia before elective PCI. The patients were divided into 4 groups according to the number of inflamed vessels as defined by showing FAI ≥−70.1 HU.

Results

In the final analysis of 69 patients (mean age 67, Male 45 (65.2%)), 18, 19, 20, 12 patients exhibited none, 1, 2, 3 inflamed vessels with FAI ≥−70.1 HU, respectively. Rest and maximal hyperemic CSF and corrected G-CFR were 1.28 [0.76,1.55] vs 1.47 [1.11, 1.81] vs 1.30 [0.94, 1.64] vs 1.27 [1.11, 2.00] ml/min/g; P=0.49, 3.50 [2.84, 5.25] vs 3.28 [2.62, 4.31] vs 3.11 [2.16, 3.63] vs 2.37 [1.40, 2.98] ml/min/g; P=0.049, 3.57 [2.17, 4.54] vs 2.25 [1.73, 3.49] vs 2.26 [1.64, 3.38] vs 1.89 [0.89, 2.32]; P=0.023, respectively. G-CFR and hyperemic CSF were both significantly lower in the group with larger number of inflamed vessels.

Conclusions

In SAP patients with significant coronary artery stenosis, G-CFR obtained by PC-CMR significantly associated with the prevalence of inflamed vessels detected by coronary CT. The extent of coronary inflammation may influence global coronary endothelium dysfunction, resulting in decreased G-CFR.

CHANGES OF ABSORBED DOSE RATE IN AIR BY CAR-BORNE SURVEY IN NAMIE TOWN, FUKUSHIMA PREFECTURE AFTER THE FUKUSHIMA DAIICHI NUCLEAR POWER PLANT ACCIDENT

The latest car-borne survey was carried out by Hirosaki University in order to grasp the local distribution of the absorbed dose rate in air after the evacuation order was lifted on Namie Town in 2017. The car-borne survey of absorbed dose rate in air was carried out on most of the roads which were accessible by car in Namie Town using a 3-in × 3-in NaI(Tl) scintillation spectrometer. The range of the absorbed dose rate in air was calculated to be 0.041-11 μGy h-1. The distribution maps of the absorbed dose rate in air were drawn based on the data obtained during the surveys in 2011, 2015 and 2017. The comparison of these absorbed dose rates in air suggests that the elevated absorbed dose rate in air in Namie Town caused by the FDNPP accident may be decreasing faster than natural decline which includes weathering effect and physical decay due to the artificial decontamination.