Prognostic value of unrecognized myocardial infarction and hyperemic coronary sinus flow in patients undergoing elective percutaneous coronary intervention

Background

Cardiac magnetic resonance (CMR) imaging is a useful instrument for the assessment of pathological and functional conditions without the need for ionizing radiation, radioactive tracers, or intravascular catheterization. Both unrecognized myocardial infarction (UMI) and impaired global myocardial blood flow (g-MBF) have been reported to be strongly associated with worse outcome in patients with cardiovascular disease. However, their combined efficacy remains undetermined.

Purpose

We sought to assess the prognostic value of the presence of UMI and pre-procedural hyperemic g-MBF evaluated by phase-contrast cine magnetic resonance imaging (PC-CMR) in patients with chronic coronary syndrome who underwent elective percutaneous coronary intervention (PCI).

Methods

A total of 177 patients with de novo functionally significant stenosis who underwent pre-PCI CMR and PCI between September, 2016 and March, 2019 were retrospectively studied. UMI was defined as a scar detected by late gadolinium enhancement (LGE) without previously diagnosed MI. g-MBF was assessed by quantifying coronary sinus flow using PC-CMR at rest and hyperemic state. The predictors of major adverse cardiac events (MACE; cardiac death, nonfatal myocardial infarction, clinically driven unplanned revascularization, or hospitalization for congestive heart failure) during follow-up were investigated.

Results

UMI was detected in 40 (27.7%) patients and rest and maximal hyperemic g-MBF evaluated by the coronary sinus flow obtained by PC-CMR were 0.95 ml/min/g and 2.26 ml/min/g, respectively. During the median follow-up of 26 months, cardiovascular death occurred in 1 patient (0.6%), nonfatal myocardial infarction occurred in 4 patients (2.3%), and clinically driven revascularization and hospitalization due to congestive heart failure occurred in 25 patients (14.1%) and 3 patients (1.7%) patients, respectively. In patients with MACE, hyperemic g-MBF was significantly lower and the prevalence of UMI were significantly higher compared with those without MACE (1.94 ml/min/g vs 2.36 ml/min/g P=0.014; 48.3% vs 23.6%, P=0.011). Cox proportional hazards model indicated that impaired hyperemic g-MBF (<2.00 ml/min/g) and the presence of UMI were significant predictors of MACE (HR 2.22, 95% CI 1.060–4.640, P=0.034; HR 2.660, 95% CI 1.290–5.470, P=0.008). During follow-up, cardiac event-free survival was significantly worse in patients with impaired hyperemic g-MBF (<2.00 ml/min/g) and UMI (log-rank χ2=11.0, P=0.010).

Conclusion

In patients with chronic coronary syndrome undergoing elective PCI, the combined assessment of UMI and hyperemic g-MBF obtained by preprocedural noninvasive CMR may provide significant prognostic information.

Funding Acknowledgement

Type of funding source: None

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

Effect of therapeutic plasma exchange on phenytoin plasma concentration in patients receiving intravenous fosphenytoin therapy

We report for patients with encephalitis treated with plasma exchange (PE) and fosphenytoin. In patient 1, phenytoin levels decreased on the maintenance dose, and the phenytoin concentration was <10 μg/mL on day 12 of administration. In patient 2, the phenytoin levels was <10 μg/mL on day 4. Increasing the fosphenytoin dose pushed the phenytoin level into therapeutic range. There were no differences between the areas under the concentration-time curve of phenytoin with and without PE. We previously reported a decline in phenytoin levels after prolonged use of fosphenytoin. Therefore, dose adjustment of fosphenytoin in patients undergoing PE may be unnecessary.

Abstract 1079: Distinct DNA methylation targets by aging and chronic inflammation

Aberrant DNA methylation is involved in many types of human cancers, and is induced by aging. In addition, it is known to be induced by chronic inflammation, and this inflammation-induced DNA methylation is considered as acceleration of age-related methylation. However, few studies addressed target genomic regions of age-related and inflammation-induced DNA methylation in a genome-wide manner. We previously demonstrated that Helicobacter pylori(HP) infection induces aberrant DNA methylation potently in human and gerbil gastric mucosa [Niwa, Cancer Res, 70:1430, 2010; Ushijima, Clin Cancer Res, 18:923, 2012]. Here, taking advantage of the potent methylation induction, we aimed to clarify the targets of methylation induction by aging and inflammation. We collected gastric mucosae from i) HP-never infected young individuals (under 40 years; n=4; G1), ii) HP-currently infected young individuals (n=4; G2), iii) HP-never-infected old individuals (above 60 years; n=4; G3), and vi) HP-currently-infected old individuals (n=4; G4). DNA methylation of 482,421 CpG probes was analyzed by Infinium Human Methylation 450K, and the probes were grouped into 270,249 genomic blocks. It was revealed that high levels of methylation were induced in 44,461 (16.5%) genomic blocks by current inflammation (G2/G1), even after correction of the influence of leucocyte infiltration. 61.8 % of the hypermethylation was acceleration of age-related methylation (G3/G1) while 21.6 % was specific to inflammation. Regions with H3K27me3 were frequently hypermethylated both by aging and inflammation. Basal methylation levels were essential for age-related hypermethylation while even regions with little basal methylation were hypermethylated by inflammation. When limited to promoter CpG islands, being a microRNA gene and high basal methylation levels strongly enhanced hypermethylation while H3K27me3 strongly enhanced inflammation-induced hypermethylation. Inflammation was capable of overriding active transcription. In young gastric mucosae (G2/G1), genes with high expression and frequent mutations in gastric cancers were more frequently methylated than in old ones (G4/G3).Methylation by inflammation was not simple acceleration of age-related methylation. Targets of aberrant DNA methylation were different between young and old gastric mucosae, and driver genes were preferentially methylated in young gastric mucosa [Yamashita, Clin Epigenet, in press].

Citation Format: Satoshi Yamashita, Sohachi Nanjo, Emil Rehnberg, Naoko Iida, Hideyuki Takeshima, Takayuki Ando, Takao Maekita, Toshiro Sugiyama, Toshikazu Ushijima. Distinct DNA methylation targets by aging and chronic inflammation [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1079.

VLDL-specific increases of fatty acids in autism spectrum disorder correlate with social interaction

BACKGROUND

Abnormalities of lipid metabolism contributing to the autism spectrum disorder (ASD) pathogenesis have been suggested, but the mechanisms are not fully understood. We aimed to characterize the lipid metabolism in ASD and to explore a biomarker for clinical evaluation.

METHODS

An age-matched case-control study was designed. Lipidomics was conducted using the plasma samples from 30 children with ASD compared to 30 typical developmental control (TD) children. Large-scale lipoprotein analyses were also conducted using the serum samples from 152 children with ASD compared to 122 TD children. Data comparing ASD to TD subjects were evaluated using univariate (Mann-Whitney test) and multivariate analyses (conditional logistic regression analysis) for main analyses using cofounders (diagnosis, sex, age, height, weight, and BMI), Spearman rank correlation coefficient, and discriminant analyses.

FINDINGS

Forty-eight significant metabolites involved in lipid biosynthesis and metabolism, oxidative stress, and synaptic function were identified in the plasma of ASD children by lipidomics. Among these, increased fatty acids (FAs), such as omega-3 (n-3) and omega-6 (n-6), showed correlations with clinical social interaction score and ASD diagnosis. Specific reductions of very-low-density lipoprotein (VLDL) and apoprotein B (APOB) in serum of ASD children also were found by large-scale lipoprotein analysis. VLDL-specific reduction in ASD was correlated with APOB, indicating VLDL-specific dyslipidaemia associated with APOB in ASD children.

INTERPRETATION

Our results demonstrated that the increases in FAs correlated positively with social interaction are due to VLDL-specific degradation, providing novel insights into the lipid metabolism underlying ASD pathophysiology.

FUNDING

This study was supported mainly by MEXT, Japan.

Sensitivity to gene dosage and gene expression affects genes with copy number variants observed among neuropsychiatric diseases

BACKGROUND

Copy number variants (CNVs) have been reported to be associated with diseases, traits, and evolution. However, it is hard to determine which gene should have priority as a target for further functional experiments if a CNV is rare or a singleton. In this study, we attempted to overcome this issue by using two approaches: by assessing the influences of gene dosage sensitivity and gene expression sensitivity. Dosage sensitive genes derived from two-round whole-genome duplication in previous studies. In addition, we proposed a cross-sectional omics approach that utilizes open data from GTEx to assess the effect of whole-genome CNVs on gene expression.

METHODS

Affymetrix Genome-Wide SNP Array 6.0 was used to detect CNVs by PennCNV and CNV Workshop. After quality controls for population stratification, family relationship and CNV detection, 287 patients with narcolepsy, 133 patients with essential hypersomnia, 380 patients with panic disorders, 164 patients with autism, 784 patients with Alzheimer disease and 1280 healthy individuals remained for the enrichment analysis.

RESULTS

Overall, significant enrichment of dosage sensitive genes was found across patients with narcolepsy, panic disorders and autism. Particularly, significant enrichment of dosage-sensitive genes in duplications was observed across all diseases except for Alzheimer disease. For deletions, less or no enrichment of dosage-sensitive genes with deletions was seen in the patients when compared to the healthy individuals. Interestingly, significant enrichments of genes with expression sensitivity in brain were observed in patients with panic disorder and autism. While duplications presented a higher burden, deletions did not cause significant differences when compared to the healthy individuals. When we assess the effect of sensitivity to genome dosage and gene expression at the same time, the highest ratio of enrichment was observed in the group including dosage-sensitive genes and genes with expression sensitivity only in brain. In addition, shared CNV regions among the five neuropsychiatric diseases were also investigated.

CONCLUSIONS

This study contributed the evidence that dosage-sensitive genes are associated with CNVs among neuropsychiatric diseases. In addition, we utilized open data from GTEx to assess the effect of whole-genome CNVs on gene expression. We also investigated shared CNV region among neuropsychiatric diseases.

Transient Receptor Potential Vanilloid 4 Regulation of Adenosine Triphosphate Release by the Adenosine Triphosphate Transporter Vesicular Nucleotide Transporter, a Novel Therapeutic Target for Gastrointestinal Baroreception and Chronic Inflammation

BACKGROUND

Transient receptor potential vanilloid 4 (TRPV4) is activated by stretch (mechanical), warm temperature, some epoxyeicosatrienoic acids, and lipopolysaccharide. TRPV4 is expressed throughout the gastrointestinal epithelia and its activation induces adenosine triphosphate (ATP) exocytosis that is involved in visceral hypersensitivity. As an ATP transporter, vesicular nucleotide transporter (VNUT) mediates ATP storage in secretory vesicles and ATP release via exocytosis upon stimulation.

SUMMARY

TRPV4 is sensitized under inflammatory conditions by a variety of factors, including proteases and serotonin, whereas methylation-dependent silencing of TRPV4 expression is associated with various pathophysiological conditions. Gastrointestinal epithelia also release ATP in response to hypo-osmolality or acid through molecular mechanisms that remain unclear. These synergistically released ATP could be involved in visceral hypersensitivity. Low concentrations of the first generation bisphosphate, clodronate, were recently reported to inhibit VNUT activity and thus clodronate may be a safe and potent therapeutic option to treat visceral pain. Key Messages: This review focuses on: (1) ATP and TRPV4 activities in gastrointestinal epithelia; (2) factors that could modulate TRPV4 activity in gastrointestinal epithelia; and (3) the inhibition of VNUT as a potential novel therapeutic strategy for functional gastrointestinal disorders.

Distinct DNA methylation targets by aging and chronic inflammation: a pilot study using gastric mucosa infected with Helicobacter pylori

Background

Aberrant DNA methylation is induced by aging and chronic inflammation in normal tissues. The induction by inflammation is widely recognized as acceleration of age-related methylation. However, few studies addressed target genomic regions and the responsible factors in a genome-wide manner. Here, we analyzed methylation targets by aging and inflammation, taking advantage of the potent methylation induction in human gastric mucosa by Helicobacter pylori infection-triggered inflammation.

Results

DNA methylation microarray analysis of 482,421 CpG probes, grouped into 270,249 genomic blocks, revealed that high levels of methylation were induced in 44,461 (16.5%) genomic blocks by inflammation, even after correction of the influence of leukocyte infiltration. A total of 61.8% of the hypermethylation was acceleration of age-related methylation while 21.6% was specific to inflammation. Regions with H3K27me3 were frequently hypermethylated both by aging and inflammation. Basal methylation levels were essential for age-related hypermethylation while even regions with little basal methylation were hypermethylated by inflammation. When limited to promoter CpG islands, being a microRNA gene and high basal methylation levels strongly enhanced hypermethylation while H3K27me3 strongly enhanced inflammation-induced hypermethylation. Inflammation was capable of overriding active transcription. In young gastric mucosae, genes with high expression and frequent mutations in gastric cancers were more frequently methylated than in old ones.

Conclusions

Methylation by inflammation was not simple acceleration of age-related methylation. Targets of aberrant DNA methylation were different between young and old gastric mucosae, and driver genes were preferentially methylated in young gastric mucosa.

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.

108Biologic significance of healed culprit plaques in stable angina versus acute coronary syndromes

Background

Healed plaques, the signature of prior subclinical plaque destabilization, are frequently found in autopsy studies and have recently been described in patients with acute coronary syndromes (ACS).

Objectives

To compare the prevalence and features of plaque vulnerability of healed culprit lesions in stable angina pectoris (SAP) versus ACS patients by using Optical Coherence Tomography (OCT).

Methods

A total of 752 patients were included: 376 patients with SAP were selected using propensity score matching, comparable to 376 patients with ACS. Healed plaques were identified using established criteria, defined as layers of different optical density on OCT. Healed plaque prevalence along with angiographic and OCT findings were compared between the two groups.

Results

Healed plaques were more frequent in SAP than in ACS patients (42.0% vs 28.7%, p<0.001). LDL-cholesterol and high sensitive C-reactive protein (hs-CRP) levels were significantly lower in SAP patients with layered plaque as compared to ACS patients with layered plaque [97.9±36.9 mg/dL vs 116.7±39.2 mg/dL, p<0.001; 0.20 (0.10–0.83) mg/L vs 4.98 (1.00–11.32) mg/L, p<0.001, respectively]. Thin-cap fibroatheroma, macrophage accumulation and microvessels were significantly less frequent in layered plaques in SAP patients as compared to those in ACS patients (12.7% vs 56.5%, p<0.001, 7.0% vs 79.6%, p<0.001, and 20.3% vs 43.5%, p<0.001, respectively). Calcifications were found more frequently among layered plaques in SAP patients than in ACS patients (51.3% vs 33.6%, p=0.006).

Conclusions

Healed plaques, detected more frequently in SAP than in ACS patients, portend different atherosclerotic backgrounds. In SAP patients, plaque destabilization frequently does not lead to occlusive thrombosis, possibly due to low level of local vulnerability and systemic inflammation. In ACS patients, the presence of high level of local vulnerability and systemic inflammation may play an important role in occlusive thrombus formation, resulting in terminating the cycles of subclinical thrombosis and healing.