Wnt signaling in cardiac development and heart diseases

The Wnt signaling pathway is a fundamental cellular communication system with extensive implications in various organs including the heart. In cardiac homeostasis, it governs essential processes like cellular proliferation, differentiation, and apoptosis, ensuring the heart's structural and functional integrity from embryonic stages and throughout life. Both canonical and non-canonical Wnt signaling pathways play a critical role during embryonic heart development in a region- and stage-specific manner. Canonical Wnt signaling also plays a significant role in heart diseases such as myocardial infarction and heart failure. However, the role of non-canonical Wnt signaling in heart diseases has not been fully elucidated. Wnt5a is a major ligand that activates non-canonical Wnt pathway, and recent studies start to clarify the role of the Wnt5a signaling axis in cardiac health and disease. In this review, we will briefly summarize the previous findings on the role of Wnt signaling pathways in heart development and diseases, and then focus on the role of Wnt5a signaling in heart failure progression. The multifaceted roles of the Wnt signaling pathway highlight its therapeutic potential for various types of heart diseases.

Incremental value of diastolic wall strain in predicting heart failure events in patients with atrial fibrillation

Diastolic wall strain (DWS), an echocardiographic index based on linear elasticity theory, has been identified as a predictor of heart failure (HF) in patients with sinus rhythm. However, its effectiveness in atrial fibrillation (AF) patients remains uncertain. This study aims to assess DWS as a predictor of HF in AF patients with preserved ejection fraction. We analysed a prospective database of AF patients undergoing transthoracic echocardiography. AF patients with reduced left ventricular ejection fraction (< 50%), posterior wall motion abnormality, hypertrophic cardiomyopathy, valvular heart disease, pericardial disease, congenital heart disease, or history of pacemaker/implantable cardioverter-defibrillator implantation or cardiac surgery were excluded. The study followed patients until HF development, death, or last visit. Follow-up for patients who underwent catheter ablation was censored on the date of their procedure. HF was ascertained based on the Framingham criteria. DWS was calculated using a validated formula: DWS = (PWs -PWd)/PWs, where PWs is the posterior wall thickness at end-systole and PWd is the posterior wall thickness at end-diastole. Among 411 study patients (mean age 69.6 years, 66% men), 20 (5%) was underwent catheter ablation and 57 (14%) developed HF during a mean follow-up of 82 months. Cox-proportional hazards demonstrated that low DWS (≤ 0.33) significantly predicted HF events (hazard ratio [HR] 3.28, 95% confidence interval [CI]) 1.81-5.94, P < 0.0001), independent of age (per 10 years; HR 1.99, 95% CI 1.35-2.93, P < 0.001), indexed left ventricular mass (per 10 g/m2; HR 1.16, 95% CI 1.05-1.27, P < 0.01), and indexed left atrial volume (per 10 mL/m2; HR 1.14, 95% CI 1.04-1.24, P < 0.01). Additionally, global log-likelihood ratio chi-square statistics indicated that DWS incrementally predicts HF development beyond age, indexed left ventricular mass, and left atrial volume (P < 0.001).

Wnt5a-YAP signaling axis mediates mechanotransduction in cardiac myocytes and contributes to contractile dysfunction induced by pressure overload

Non-canonical Wnt signaling activated by Wnt5a/Wnt11 is required for the second heart field development in mice. However, the pathophysiological role of non-canonical Wnt signaling in the adult heart has not been fully elucidated. Here we show that cardiomyocyte-specific Wnt5a knockout mice exhibit improved systolic function and reduced expression of mechanosensitive genes including Nppb when subjected to pressure overload. In cultured cardiomyocytes, Wnt5a knockdown reduced Nppb upregulation induced by cyclic cell stretch. Upstream analysis revealed that TEAD1, a transcription factor that acts with Hippo pathway co-activator YAP, was downregulated both in vitro and in vivo by Wnt5a knockdown/knockout. YAP nuclear translocation was induced by cell stretch and attenuated by Wnt5a knockdown. Wnt5a knockdown-induced Nppb downregulation during cell stretch was rescued by Hippo inhibition, and the rescue effect was canceled by knockdown of YAP. These results collectively suggest that Wnt5a-YAP signaling axis mediates mechanotransduction in cardiomyocytes and contributes to heart failure progression.

Efficacy of Intravascular Ultrasound-Based 3D Wiring Using the Tip Detection Method for CTO Intervention

To perform intravascular ultrasound (IVUS)-based real-time 3-dimensional wiring in chronic total occlusion percutaneous coronary intervention, we devised a tip detection method and developed AnteOwl WR (AO)-IVUS, which is an upgraded version of Navifocus WR (Navi)-IVUS with an added pull back transducer system. We compared the procedural outcomes of AO-IVUS-based 3-dimensional wiring using the tip detection method (n = 30) and Navi-IVUS-based conventional wiring (n = 17) in chronic total occlusion percutaneous coronary intervention. The success rate of IVUS-guided wiring was markedly improved in the AO-IVUS group compared with the Navi-IVUS group (93% vs 59% of cases, respectively; P = 0.007). In cases of successful IVUS-guided wiring, the IVUS-guided wiring time was markedly improved in the AO-IVUS group compared with the Navi-IVUS group (9 ± 8 minutes vs 24 ± 26 minutes, respectively; P = 0.001). There were 2 successful cases of tip detection-antegrade dissection and re-entry in the AO-IVUS group.

Diagnostic accuracy and clinical usefulness of erythrocyte creatine content to predict the improvement of anaemia in patients receiving maintenance haemodialysis

BACKGROUND

The improvement of anaemia over time by erythropoiesis stimulating agent (ESA) is associated with better survival in haemodialysis patients. We previously reported that erythrocyte creatine content, a marker of erythropoietic capacity, was a reliable marker to estimate the effectiveness of ESA. The aim of this study was to examine the accuracy and clinical usefulness of erythrocyte creatine content to predict the improvement of anaemia in haemodialysis patients.

METHODS

ESA dose was fixed 3 months prior to the enrollment and was maintained throughout the study period. Erythrocyte creatine content and haematologic indices were measured at baseline in 92 patients receiving maintenance haemodialysis. Haemoglobin was also measured 3 months after. Improvement of anaemia was defined as ≥ 0.8 g/dL change in haemoglobin from baseline to 3 months.

RESULTS

Erythrocyte creatine content was significantly higher in 32 patients with improvement of anaemia compared to 60 patients with no improvement of anaemia (2.47 ± 0.74 vs. 1.57 ± 0.49 μmol/gHb, P = 0.0001). When 9 variables (erythrocyte creatine content, ESA dose, reticulocyte, haptoglobin, haemoglobin at baseline, serum calcium, intact parathyroid hormone, transferrin saturation and serum ferritin) were used in the multivariate logistic regression analysis, erythrocyte creatine emerged as the most important variable associated with the improvement of anaemia (P = 0.0001). The optimal cut-off point of erythrocyte creatine content to detect the improvement of anaemia was 1.78 μmol/gHb (Area under the curve: 0.86). Sensitivity and specificity of erythrocyte creatine content to detect the improvement of anaemia were 90.6% and 83.3%.

CONCLUSION

Erythrocyte creatine content is a reliable marker to predict the improvement of anaemia 3 months ahead in patients receiving maintenance haemodialysis.

Elevated Aminotransferase Levels and Intracerebral Hemorrhage Deaths in a General Japanese Population

Although chronic liver disease has been associated with cardiovascular disease, to which metabolic syndrome might be related, intracerebral hemorrhage (ICH) generally has not been focused. Associations of chronic liver disease assessed by aspartate (AST) and alanine (ALT) aminotransferase levels with ICH deaths were examined using 15,952 subjects without a history of cardiovascular disease who underwent annual health checkups in 1997 in Japan. Proportional hazards regression analyses adjusted for age, sex, hypertension, current smoking, diabetes mellitus, drinking habits, excess body weight, and hypercholesterolemia were performed. During a mean follow-up of 18.6 ± 7.2 years, there were 227 stroke deaths (including 124 ischemic and 60 ICH deaths) and 135 coronary deaths. Elevated aminotransferase levels, defined as a serum AST or ALT level of ≥ 30 IU/L were significantly associated with ICH deaths (hazard ratio (HR) = 2.72, 95% confidence interval (CI) = 1.56-4.73, P = 0.0004). Because elevated aminotransferase levels are frequently observed in alcoholic or metabolic liver diseases, additional analyses were performed to examine the effect of drinking habits and/or metabolic syndrome on the association of elevated aminotransferase levels with ICH deaths. After exclusion of subjects with any drinking habit (n = 9,941), elevated aminotransferase levels were significantly associated with ICH deaths (HR = 2.88, 95%CI = 1.44-5.76, P = 0.0028). After exclusion of subjects with at least one metabolic syndrome component (n = 5,672), elevated aminotransferase levels were significantly associated with ICH deaths (HR = 6.47, 95% CI = 1.85-22.6, P = 0.0035). Elevated aminotransferase levels were not associated with ischemic stroke or coronary deaths in any models. Elevated aminotransferase levels were significantly associated with ICH deaths, independent of drinking habits, or metabolic syndrome.

Frequency and Distribution of Sheet and Nodular Calcification in Coronary Arteries in Japanese Patients

Whether a nodular calcification (NC), which is the precursor to intracoronary thrombosis, is focally or diffusely distributed in the coronary tree has major implications for ongoing efforts to identify. This study aimed to investigate the frequency and spatial distribution patterns of sheet calcification (SC) and NC in a 3-vessel examination of autopsied human hearts.A total of 323 coronary artery specimens from 110 cadavers were obtained from autopsy cases. After fixation and decalcification, the coronary artery trees were cut every 5 mm into 4-μm transverse cross-sections for histological assessment. An SC was defined as a plate-like calcification of > 1 quadrant of the vessel or > 3 mm in diameter, and NC as nodular calcium deposits separated by fibrin, and a deposit size > 1 mm in diameter.Of the 6,306 histological cross-sections, SCs and NCs were identified in 1,627 (26%) and 233 (4%) cross-sections, respectively. SCs and NCs had a similar distribution pattern in all 3 coronary arteries. In the left anterior descending artery (LAD), NCs were predominantly located in the proximal segment: the first 45 mm from the LAD ostium (72%) and the first 60 mm from the LAD ostium (84%), respectively. However, NCs were evenly distributed throughout the length of the coronary artery in the right coronary artery (RCA) and left circumflex artery (LCX).NCs coexisted with SCs, and tended to cluster in predictable parts within the proximal segments of the LAD, but were evenly distributed throughout the RCA and LCX in coronary arteries from cadavers.

Increased Incidence of ECG Abnormalities in the General Population During the COVID-19 Pandemic

To examine the effect of the COVID-19 pandemic on the cardiovascular system in the general population, we compared ECG changes after the onset of the COVID-19 pandemic with those before the pandemic period. The incidence of newly appeared ECG abnormalities (T wave abnormalities, ST-segment depression including minor changes, and abnormal Q waves) from 2019 to 2020 (COVID-19 period) was compared with that from 2018 to 2019 (control period) in subjects 40 to 74 years of age without a history of cardiovascular disease who had 12-lead ECG recordings during annual health checkups offered to adult citizens of Moriguchi City, Osaka, Japan. Logistic regression analyses were performed after adjusting for cardiovascular risk factors. There were 5,221 eligible subjects in the control period and 4,100 eligible subjects in the COVID-19 period. The incidences of newly appeared ECG abnormalities were 5.2% for T wave abnormalities, 2.8% for ST-segment depression, and 1.1% for abnormal Q waves in the control period, whereas they were 5.8%, 4.3%, and 1.7% respectively, in the COVID-19 period. The incidence of ST-segment depression (odds ratio (OR) = 1.59, 95% confidence interval (CI) = 1.27-1.98, P < 0.0001) and that of abnormal Q waves (OR = 1.56, 95%CI = 1.09-2.22, P = 0.0149) in the COVID-19 period were significantly higher compared to those of the control period. In conclusion, increased incidences of newly appeared ST-segment depression and abnormal Q waves were observed during the COVID-19 pandemic period.

Analysis of site-specific late potentials using a novel Holter signal-averaged electrocardiography in patients with Brugada syndrome

BACKGROUND

The utility of late potentials on signal-averaged electrocardiography (SAECG) for risk stratification in patients with Brugada syndrome (BrS) remains controversial. Late potentials on conventional SAECG with Frank leads may be insufficiently sensitive to detect site-specific late potentials in right precordial leads.

OBJECTIVE

The purpose of this study was to evaluate the utility of site-specific late potentials using a novel unipolar Holter-SAECG system for risk stratification in patients with BrS.

METHODS

Consecutive symptomatic (n = 20) and asymptomatic (n = 21) patients with BrS who underwent investigation using conventional SAECG and a novel unipolar Holter-SAECG system were enrolled. We evaluated clinical characteristics and outcomes and compared late potentials on the 2 SAECGs between both groups and patients with and without cardiac events (CEs) (sudden cardiac death or sustained ventricular tachyarrhythmias) during the follow-up period.

RESULTS

During mean follow-up of 76 months, 10 patients (24%) had CEs. There were no significant differences in late potentials on conventional SAECG between symptomatic and asymptomatic patients. On the Holter-SAECG system, RMS40 in lead V₂ in the third intercostal space (3L-V₂) at the nighttime was significantly lower in the symptomatic group than in the asymptomatic group (5.5 ± 0.8 μV and 8.2 ± 0.8 μV, respectively; P = .027). Univariate analysis of predictive values for CE showed that hazard ratios of daytime and nighttime RMS40 in lead 3L-V₂ of <7.7 μV and <6.1 μV were 7.58 and 6.14, respectively.

CONCLUSION

Site-specific late potentials in lead 3L-V₂ measured using the novel Holter-SAECG system may be a useful marker for high-risk patients with BrS.

Related factors and changes of angiopoietin-like protein 2 with chronic heart failure patients participating in phase III cardiac rehabilitation

Funding Acknowledgements

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): the research grant D2 from Kansai Medical University

Objectives

Angiopoietin-like protein 2 (ANGPTL2) is a protein, whose structure is similar to that of angiopoietin, but binds to a different receptor. Overexpression of ANGPTL2 promotes chronic inflammation and relates to the development of aging-related diseases. ANGPTL2 has been reported to be mainly secreted by adipose tissue. Although ANGPTL2 has been implicated in the pathogenesis of heart failure, there are no studies about serum ANGPTL2 levels in patients with heart failure participating in cardiac rehabilitation program. The aim of this study was to investigate the characteristics, related factors and changes of ANGPTL2 in patients with chronic heart failure during phase III of cardiac rehabilitation program.

Methods

The subjects included 57 patients (70.1 ± 10.2 years old; 46 men) with chronic heart failure whose serum ANGPTL2 levels were measured during the maintenance phase of cardiac rehabilitation program. Furthermore, we classified 25 patients (70.6 ± 7.5 years old; 23 men) from the 6-month course into a reduced group and an unchanged group to characterize change in ANGPTL2. We excluded patients who were admitted or discharged within 3 months of the evaluation of serum ANGPTL2. We evaluated exercise tolerance using the cardiopulmonary exercise test, grip strength, body composition using a body composition analyzer, blood examinations, and echocardiography. Serum ANGPTL2 was measured by solid-phase sandwich enzyme-linked immunosorbent assay (ELISA).

Results

The median value of ANGPTL2 was 4.05 ng/ml. ANGPTL2 was positively correlated with body weight, body mass index, body fat mass, body fat percentage, C-reactive protein (CRP) and total protein (TP) levels, and negatively correlated with skeletal muscle mass percentage and anaerobic threshold (AT). From the result of the logistic regression analysis, AT (OR=0.68, 95% CI:0.47-0.97and TP (OR=20.1, 95% CI:2.52-160.63) were extracted as independent factors related to the level of ANGPTL2. In addition, overall serum ANGPTL2 levels decreased significantly after 6 months. Changes in ANGPTL2 in the reduced group showed a positive correlation between baseline peak VO2, left ventricular ejection fraction and skeletal muscle rate, and a negative correlation with baseline ANGPTL2, CRP, body fat mass. In an unchanged group, HbA1c increased, but no significant change was observed in other factors.

Conclusions

Exercise tolerance in patients with chronic heart failure during maintenance phase might be related to the inflammation marker ANGPTL2. Serum ANGPTL2 levels with stable chronic heart failure patients decreased significantly 6 months after continued cardiac rehabilitation.

Repetitive spikes of glucose and lipid induce senescence-like phenotypes of bone marrow stem cells through H3K27me3 demethylase-mediated epigenetic regulation

Bone marrow-derived endothelial progenitor cells (EPCs) contribute to endothelial repair and angiogenesis. Reduced number of circulating EPCs is associated with future cardiovascular events. We tested whether dysregulated glucose and/or triglyceride (TG) metabolism has an impact on EPC homeostasis. The analysis of metabolic factors associated with circulating EPC number in humans revealed that postprandial hyperglycemia is negatively correlated with circulating EPC number, and this correlation appears to be further enhanced in the presence of postprandial hypertriglyceridemia (hTG). We therefore examined the effect of glucose/TG spikes on bone marrow lineage-sca-1+ c-kit+ (LSK) cells in mice, because primitive EPCs reside in bone marrow LSK fraction. Repetitive glucose + lipid (GL) spikes, but not glucose (G) or lipid (L) spikes alone, induced senescence-like phenotypes of LSK cells, and this phenomenon was reversible after cessation of GL spikes. G spikes and GL spikes differentially affected transcriptional program of LSK cell metabolism and differentiation. GL spikes upregulated a histone H3K27 demethylase JMJD3, and inhibition of JMJD3 eliminated GL spikes-induced LSK cell senescence-like phenotypes. These observations suggest that postprandial glucose/TG dysmetabolism modulate transcriptional regulation in LSK cells through H3K27 demethylase-mediated epigenetic regulation, leading to senescence-like phenotypes of LSK cells, reduced number of circulating EPCs, and development of atherosclerotic cardiovascular disease.NEW & NOTEWORTHY Combination of hyperglycemia and hypertriglyceridemia is associated with increased risk of atherosclerotic cardiovascular disease. We found that 1) hypertriglyceridemia may enhance the negative impact of hyperglycemia on circulating EPC number in humans and 2) metabolic stress induced by glucose + triglyceride spikes in mice results in senescence-like phenotypes of bone marrow stem/progenitor cells via H3K27me3 demethylase-mediated epigenetic regulation. These findings have important implications for understanding the pathogenesis of atherosclerotic cardiovascular disease in patients with T2DM.

External validation of H2ARDD score for the prediction of heart failure events in patients with atrial fibrillation

Background

Heart failure is an important consequence in patients with atrial fibrillation (AF) which is associated with worse prognosis. The H2ARDD score, calculated from 5 clinical risk factors, was reported as a predictor of heart failure events in patients with AF. However, this score has not been externally validated.

Purpose

The purpose of this study was to evaluate and validate the usefulness of the H2ARDD score for the prediction of heart failure events in AF patients.

Methods

We used prospective data of patients with AF followed up from 2007 to 2017 in our institute. Patients with active cancer were excluded according to the previous report. H2ARDD score was calculated as follows; history of heart disease=2 points, anemia=1 point, renal dysfunction=1 point, diabetes =1 point, diuretic use=1 point (range from 0 to 6 points). Outcome of interest was defined as heart failure events including new-onset heart failure and death with heart failure. Heart failure was ascertained based on the Framingham criteria. Univariable and multivariable Cox-proportional hazards model were used to assess the risk of heart failure events. Heart failure events-free survival was estimated with Kaplan-Meier methods, and the predictive accuracy of the H2ARDD score for the prediction of heart failure events was measured by the area under the receiver operating characteristic (ROC) curve.

Results

Of 562 AF patients, 522 (age 69±10 year–old, 64.9%men) met study criteria. Patients who had a history of heart disease was 185 (35%), diabetes mellitus was 135 (26%), anemia was 54 (10%), renal dysfunction was 221 (43%), and diuretic use was 193 (37%). The mean H2ARDD score was 1.88±1.57. Of all study patients, 84 (16.2%) developed heart failure events during a mean follow–up of 54±42 months. Patients who developed heart failure events in 1 year was 24 (4.6%). In multivariable Cox–proportional hazards model, H2ARDD score was shown as an significant predictor for heart failure events (hazard ratio: 1.56, 95% confidence interval: 1.36 - 1.79, P&lt;0.0001), independently of age (per 10 years, hazard ratio: 1.35, 95% confidence interval: 1.03 – 1.78, P&lt;0.05). In the Kaplan–Meier analyses stratified by H2ARDD score (0–1, 2–3, 4–6), patients who had a higher H2ARDD sore had significantly worse heart failure event-free survival (log-rank P&lt;0.0001) (Figure 1). The area under the ROC curve for the prediction of heart failure events in 1-year was 0.812 (95% confidence interval: 0.737 – 0.887, P&lt;0.0001), and the best cut-off value was ≥4 points (sensitivity: 67%, specificity: 83%) (Figure 2).

Conclusion

H2ARDD score was demonstrated as a significant independent predictor for the prediction of heart failure events, with high predictive accuracy. H2ARDD score may be useful for heart failure risk stratification of AF patients.

Funding Acknowledgement

Type of funding sources: None. Figure 1Figure 2

Diagnostic Accuracy of Optical Frequency Domain Imaging for Identifying Necrotic Cores with Intraplaque Hemorrhage in Advanced Human Carotid Plaques

This study investigated whether optical frequency domain imaging (OFDI) can identify carotid artery vulnerable plaque characteristics, focusing on lipid-rich necrotic core (NC) and intraplaque hemorrhage (IPH). Fourteen patients scheduled for carotid endarterectomy underwent OFDI scan during preoperative angiography. Atherosclerotic plaque specimens obtained from carotid endarterectomy were cut every 3-4 mm into 4-μm transverse cross-sections and stained with standard methods. Each cross-section was matched with OFDI, and histologically classified into either fibrous, calcific, pathological intimal thickening (PIT), and NC. Of 75 histologic cross-sections, 6 were categorized as fibrous (8%), 18 as calcific (24%), 9 as PIT (12%), and 42 as NC (56%). Tissues categorized as NC had significantly higher OFDI signal attenuation rates than the other tissues (p <0.001), followed by PIT, calcific, and fibrous tissues. The receiver operating characteristic analysis indicated that attenuation rates of >0.023 and >0.031 predicted the presence of NC and IPH with high areas under the curve of 0.91 and 0.88, respectively. OFDI provides potential capability for the detection of NCs with IPH of carotid artery plaques by quantitatively analyzing the attenuation rate.

Serum Angiopoietin-Like Protein 2 and NT-Pro BNP Levels and Their Associated Factors in Patients with Chronic Heart Failure Participating in a Phase III Cardiac Rehabilitation Program

Angiopoietin-like protein 2 (ANGPTL2) promotes chronic inflammation and plays a key role in the pathogenesis of heart failure. Cardiac rehabilitation (CR) is an integral component of heart failure management and has been shown to have anti-inflammatory effects. However, ANGPTL2 concentration in chronic heart failure patients undergoing CR has not been evaluated. This study aimed to investigate serum ANGPTL2 levels and their associated factors and compare the results with those of N-terminal pro-brain natriuretic peptide (NT-proBNP) in patients with chronic heart failure undergoing phase III CR.A total of 56 patients were enrolled. Clinical characteristics including body composition, grip strength, exercise tolerance, duration of CR, blood counts and biochemistry, and echocardiographic parameters were evaluated for their association with serum ANGPTL2 and NT-proBNP levels.The median (first and third quartiles) value of ANGPTL2 was 4.05 (2.70-5.57) ng/mL. Clinical parameters that correlated with serum ANGPTL2 levels were body weight, body mass index, body fat mass, body fat percentage, anaerobic threshold (AT), C-reactive protein, and total protein (TP), which were mostly distinct from those that correlated with serum NT-proBNP levels. A multivariate analysis revealed that AT and TP were independent factors related to ANGPTL2 levels, whereas age, left ventricular ejection fraction, and left atrial dimension were independently related to NT-proBNP levels.These observations suggest that CR increases the exercise tolerance and exhibits anti-inflammatory effects simultaneously, and this situation is reflected by decreased serum ANGPLT2 and TP levels. ANGPTL2 may be a useful marker of inflammation and impaired exercise tolerance in patients with chronic heart failure.

Predictors of in-hospital mortality in patients with infective endocarditis

BACKGROUND

Infective endocarditis is a serious septic disease, and the epidemiological profile has changed over the last decade. However, there is a paucity of data regarding the current outcome and predictor of in-hospital mortality in patients with infective endocarditis.

METHODS

Consecutive patients diagnosed as infective endocarditis based on the modified Duke criteria at Kansai Medical University hospital from January 2006 to June 2019 were prospectively included. The primary outcome was in-hospital mortality. Cox proportional hazards modelling was used to assess risk factors of in-hospital mortality.

RESULTS

Of 137 consecutive patients with infective endocarditis (age 60 ± 17 years-old, 62% men, 65% underlying cardiac disease, 11% chronic haemodialysis), 18 (13%) died during hospitalisation. Age and sex were not associated with in-hospital mortality. Patients on chronic haemodialysis exhibited significantly higher in-hospital mortality rate than those without (47 vs. 9%). After adjusting for comorbidities in a multivariate Cox proportional hazards model, chronic haemodialysis was a significant predictor of in-hospital mortality [hazard ratio (HR) 4.22, 95% confidential interval (CI): 1.49-12.0, p < 0.01], independently of C-reactive protein (per 1 mg/dl; HR 1.07, 95%CI: 1.02-1.12, p < 0.05).

CONCLUSIONS

Infective endocarditis in patients on chronic haemodialysis is a serious life-threatening condition that requires early diagnosis and an effective therapeutic approach.

Tangential signal dropout artefact in optical frequency domain imaging

BACKGROUND

Tangential signal dropout (TSD), which occurs when the optical frequency domain imaging (OFDI) beam strikes the vessel wall under a glancing angle and travels almost parallel to the vessel wall, is the most important imaging artefact leading to the erroneous diagnosis of lipid-rich plaques.

AIMS

This study aimed to evaluate the OFDI artefact of TSD, which mimics the appearance of lipid-rich plaque and macrophage (Mø) infiltration.

METHODS

A total of 1,019 histological cross-sections from 23 autopsy hearts were matched with the corresponding OFDI images. Of these, 232 OFDI cross-sections that contained signal-poor regions with diffuse borders were classified as lipid-rich plaques. The angle θ was calculated between the OFDI beam that strikes the edge of the luminal surface of the low-intensity region and that which strikes the surface line of the low-intensity region.

RESULTS

On histological evaluation, 182 (78%) cross-sections were classified as histologically lipidic/Mø infiltration, while the remaining 50 (22%) cross-sections were classified as histologically non-lipidic/Mø infiltration. The angle θ was significantly smaller in the non-lipidic/Mø infiltration group than in the lipidic/Mø infiltration group (12±6° versus 37±14°, p<0.001). Receiver operating curve analysis revealed that the optimal cut-off value of the incident angle for predicting TSD was 23° with an area under the curve of 0.98.

CONCLUSIONS

When the OFDI imaging beam strikes the tissue at an angle θ<23°, TSD artefact could occur. To eliminate image misinterpretation, our findings suggest that the OFDI catheter geometry should be considered for the accurate diagnosis of lipid-rich plaques and Mø infiltration.

Factors Associated with Coronary In-Stent Restenosis after Drug-Eluting Stent Implantation in Patients on Chronic Hemodialysis

AIMS

Recently, drug-eluting stents (DESs) have been widely adopted for patients on chronic hemodialysis (HD). However, whether DES implantation is associated with a reduced rate of in-stent restenosis (ISR) is unclear. We investigated the incidence of ISR and its predictors in patients on HD after DES implantation.

METHODS AND RESULTS

We analyzed 194 consecutive patients (331 lesions) on HD who underwent follow-up angiography after DES implantation. ISR was observed in 74 lesions (22.4%). Angiographically, the relative incidence of AHA/ACC type C lesion was increased (47 vs. 32%; p = 0.043), the minimal lumen diameter (MLD) before DES implantation was smaller (0.82 ± 0.49 vs. 0.97 ± 0.45 mm; p < 0.01), and the lesion length (LL) was increased (30.2 ± 16.1 vs. 24.4 ± 12.1 mm; p = 0.023) in lesions with ISR compared to those without ISR. The rate of rotational atherectomy use was also increased in lesions with ISR compared to those without ISR (50% vs. 25%; p < 0.01). In a multivariate analysis, the MLD before DES implantation (odds ratio [OR] = 0.50, 95% confidence interval [CI] 0.27-0.91, p = 0.024), LL (OR = 1.02, 95% CI 1.00-1.04, p = 0.030) and the use of rotational atherectomy (OR = 2.71, 95% CI 1.55-4.72, p < 0.01) were independent predictors of ISR. The incidence of ISR was similar between lesions treated with the first-generation (25.8%) and the second-generation DESs (20.4%).

CONCLUSIONS

ISR was observed in 74 lesions (22.4%). A small MLD, long LL, and the use of rotational atherectomy were independent predictors of ISR after DES implantation in patients on HD. There was no significant difference in the ISR rate between the first- and the second-generation DESs.

The incidence, natural history, and predictive factors for tissue protrusion after drug-eluting stent implantation

OBJECTIVES AND BACKGROUND

Although tissue protrusion (TP) between the stent struts after stent implantation has been implicate as a potential factor of stent failure, the incidence, natural history, and predictive factor of TP after stent implantation remains unclear. This prospective study evaluated the fate of TP after drug-eluting stent (DES) deployment using optical coherence tomography (OCT).

METHOD AND RESULT

This study analyzed TP for 42 lesions after DES in which three serial OCTs, including preprocedure, postprocedure, and 1-month after the procedure were performed. TP was classified into the five groups: (a) persistent, (b) progressive, (c) healed, (d) regressive, and (e) late-acquired. Immediately after the procedure, 100 TPs in 37 lesions (88%) were identified. Of those, 53 (53%) were persistent, 3 (3%) were progressive, 20 (20%) were healed, and 24 (24%) were regressed at 1-month follow-up. Seven TPs in five patients (13%) were observed only at 1-month follow-up (late-acquired).

CONCLUSION

In lesions with late-acquired TP, calcified nodule was identified as an underlying plaque morphology on preprocedural OCT. A serial OCT analysis found TP occurred not only immediately after DES implantation, but also 1-month after DES implantation.

Automated classification of coronary atherosclerotic plaque in optical frequency domain imaging based on deep learning

BACKGROUND AND AIMS

We developed a deep learning (DL) model for automated atherosclerotic plaque categorization using optical frequency domain imaging (OFDI) and performed quantitative and visual evaluations.

METHODS

A total of 1103 histological cross-sections from 45 autopsy hearts were examined to compare the ex vivo OFDI scans. The images were segmented and annotated considering four histological categories: pathological intimal thickening (PIT), fibrous cap atheroma (FA), fibrocalcific plaque (FC), and healed erosion/rupture (HER). The DL model was developed based on pyramid scene parsing network (PSPNet). Given an input image, a convolutional neural network (ResNet50) was used as an encoder to generate feature maps of the last convolutional layer.

RESULTS

For the quantitative evaluation, the mean F-score and IoU values, which are used to evaluate how close the predicted results are to the ground truth, were used. The validation and test dataset had F-score and IoU values of 0.63, 0.49, and 0.66, 0.52, respectively. For the section-level diagnostic accuracy, the areas under the receiver-operating characteristic curve produced by the DL model for FC, PIT, FA, and HER were 0.91, 0.85, 0.86, and 0.86, respectively, and were comparable to those of an expert observer.

CONCLUSIONS

DL semantic segmentation of coronary plaques in OFDI images was used as a tool to automatically categorize atherosclerotic plaques using histological findings as the gold standard. The proposed method can support interventional cardiologists in understanding histological properties of plaques.

Differential effect of malnutrition between patients hospitalized with new-onset heart failure and worsening of chronic heart failure

Aims

We aimed to investigate the differences in the prevalence, severity, and prognostic impact of malnutrition between patients with new‐onset heart failure (HF) and worsening of chronic HF.

Methods and results

In older (≥60 years) hospitalized patients with acute HF, malnutrition was assessed according to the Geriatric Nutritional Risk Index (GNRI). A score <92 was defined as malnutrition. The primary endpoint was a composite endpoint, including cardiac death or rehospitalization for HF. Among 210 patients, 37% (52/142) of patients with new‐onset HF and 31% (21/68) of patients with worsening of chronic HF had malnutrition (P = 0.41). The GNRI classification was comparable between the two groups. Kaplan–Meier analysis revealed a significant difference in the incidence of the composite endpoint in patients with new‐onset HF (GNRI < 92 vs. GNRI ≥ 92: 50% vs. 32%, P = 0.007), but not in patients with worsening of chronic HF (GNRI < 92 vs. GNRI ≥ 92: 67% vs. 68%, P = 0.91). The adjusted Cox proportional hazards model demonstrated that a GNRI of <92 was an independent prognostic factor for the composite endpoint in patients with new‐onset HF only.

Conclusions

Among older hospitalized patients with acute HF, the prevalence and severity of malnutrition were comparable between the two categories of patients. Malnutrition was an independent prognostic factor in patients with new‐onset HF, while clinical prognosis was poor in patients with worsening of HF, irrespective of malnutrition. The prognostic impact of malnutrition differs between new‐onset HF and worsening of chronic HF.

Interobserver variability in assessments of atherosclerotic lesion type via optical frequency domain imaging

BACKGROUND

To date, there have been no data available regarding the diagnostic performance of optical frequency domain imaging (OFDI) for in vivo histological classification of atherosclerotic lesions. This study investigated whether OFDI can be used to diagnose and classify histological atherosclerotic lesions in the coronary artery by ex vivo histological examinations.

METHODS

Three-hundred-fifteen histological cross-sections from 21 autopsy hearts were matched with the OFDI images. Histological cross-sections were classified into six categories: adaptive intimal thickening (AIT), pathological intimal thickening (PIT), fibrous cap atheroma (FA), fibrocalcific plaque (FC), calcified nodule, and healed erosion/rupture. The five observers with different years of experience in the interpretation of OFDI provided a single diagnosis for the OFDI scans of each cross-section according to the aforementioned six histological categories. The diagnostic accuracy and interobserver variability of lesion types for each OFDI observer were determined using histology as the gold standard.

RESULTS

The overall agreement rates between OFDI and histopathologic diagnosis for OFDI observers 1-5 were 81%, 70%, 68%, 61%, and 50% (κ values of 0.75, 0.61, 0.58, 0.49, and 0.36), respectively. Although the diagnostic accuracy of OFDI for detecting AIT and FC was excellent for all five observers, the sensitivity, and positive predictive values of OFDI for detecting PIT and FA were low in proportion to years of experience.

CONCLUSION

The diagnostic accuracy of atherosclerotic tissue properties from OFDI scans correlated with the observers' years of experience, especially when lesions contained lipid components.

Effects of dapagliflozin on renin-angiotensin-aldosterone system under renin-angiotensin system inhibitor administration

Sodium-glucose cotransporter-2 inhibitors (SGLT2Is) are reported to prevent cardiovascular events by a mechanism possibly including diuresis and sodium excretion. In this respect, diuresis-induced compensatory upregulation of the renin-angiotensin-aldosterone (RAA) system should be clarified and we performed a randomized controlled trial using dapagliflozin, an SGLT2I. Hypertensive diabetic patients taking angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers were randomly assigned to a dapagliflozin group (DAPA) or a control group (CTRL) with the difference in the changes in plasma renin activity (PRA) after 24 weeks of the treatment as the primary outcome. PRA, plasma aldosterone concentration (PAC), age, sex, BMI, blood pressure, pulse rate, eGFRcys, and HbA1c were not different between the groups at baseline. After 24 weeks, the changes in the PRA from the baseline of the DAPA (n = 44) and CTRL (n = 39) groups were 6.30 ± 15.55 and 1.42 ± 11.43 ng/mL/h, respectively (p = 0.11) although the power of detection was too small. However, post hoc nonparametric analyses revealed that there was a definite increase in the PRA and PAC in the DAPA group (p < 0.0001 and p = 0.00025, respectively) but not in the CTRL group. The PRA in the DAPA group after 24 weeks treatment was significantly elevated compared to the CTRL group (p = 0.013) but not for the PAC. Accordingly, it would be suggested that dapagliflozin may not induce a profound increase, if any, in PAC after 24 weeks of treatment in hypertensive type 2 diabetic patients under RAA suppression.

The accuracy and interobserver variability in the assessment of coronary atherosclerotic plaques by optical frequency domain imaging: involving five observers with different levels of coronary imaging

Background

Whether optical frequency domain imaging (OFDI) images can realize pathological diagnosis of coronary atherosclerotic plaques, and whether its diagnostic accuracy of lesion types varies depending on the personal experience of the clinician caring for coronary intervention have not been elucidated.

Purpose

This study investigated the interobserver variability in characterizing atherosclerotic plaque types by OFDI for multiple OFDI observers with levels of different experience.

Methods

Three-hundred-thirty-three histological cross-sections from 21 autopsy hearts were co-registered with the corresponding OFDI images. Histological cross-sections were classified into the following 7 lesion types according to the modified AHA atherosclerosis classification by a single experienced pathologist blinded for OCT findings: adaptive intimal thickening (AIT), intimal xanthoma (IX), pathological intimal thickening (PIT), fibrous cap atheroma (FA), fibrocalcific plaque (FC), calcified nodule (CN), and healed erosion/rupture (HER). The five OFDI observers, unaware of the histological diagnosis, provided a single diagnosis for each corresponding OFDI image. The OFDI observer 1 was an expert interventional cardiologist with sufficient experience in OFDI imaging, followed by the OFDI observer 2, 3, and 4 as middle career interventional cardiologists who had completed training ten, seven, and four years. The OFDI observer 5 was a young career interventional cardiologist. The diagnostic accuracy of lesion types for each OFDI observer was determined taking histology as a gold standard.

Results

On histological analysis, 13% of histological cross-sections were diagnosed as AIT, 5% as IX, 23% as PIT, 25% as FA, 27% as FC, 2% as CN, and 5% as HER. The overall agreement between OFDI diagnosis and histopathologic diagnosis for OFDI observer 1 to 5 was 77%, 62%, 61%, 56%, and 46% (k values of 0.71, 0.54, 0.54, 0.45, and 0.33), respectively. Although the performance for characterizing AIT and FC was excellent and comparable among all OFDI observers, the sensitivity and positive predictive value for characterizing IX, PIT and FA varied depending on the OFDI observers' years of experience (Table). The main causes of false-positive or -negative diagnosis of FA were IX and PIT for all OFDI observers.

Conclusion

The diagnostic accuracy of atherosclerotic tissue properties from OFDI images correlated with the observers' years of experience, subspecialty training in coronary imaging, which suggests that the interpretation of OFDI images requires expertise and can be challenging to a less experienced reader.

Table 1

Funding Acknowledgement

Type of funding source: None

Usefulness of H2FPEF score as an independent predictor of heart failure development in patients with atrial fibrillation

Background

The H2 FPEF score, which based on simple clinical characteristics and echocardiography, enables discrimination of HFpEF from noncardiac causes of dyspnea.

Purpose

We sought to evaluate whether H2 FPEF score predicts congestive heart failure (CHF) development in patients with atrial fibrillation (AF).

Methods

Among adult AF patients who underwent transthoracic echocardiography between July 2007 and December 2008, those with preserved left ventricular ejection fraction (LVEF) (≥50%) were included and followed up to new-onset CHF events. Patients with a history of CHF, cardiac surgery, or significant left-sided valvular heart disease were excluded. The H2 FPEF score was calculated from 6 variables (obesity = 2 points, treatment with ≥2 antihypertensive drugs = 1 point, AF = 3 points, echocardiographic pulmonary artery systolic pressure &gt;35 mmHg = 1 point, age &gt;60 years = 1 point, and echocardiographic E/e'ratio &gt;9 = 1 point). CHF was ascertained using Framingham criteria. Cox-proportional hazards modeling was used to assess risk of CHF development.

Results

Of 562 AF patients, 367 (69±10 year old, 66% men) met all study criteria. Of whom, 37 (10%) developed CHF events during a mean follow–up of 56±43 months. The mean H2 FPEF score was 5.50±1.14, and the number of patients with H2 FPEF score ≥7 was 64 (17%). After adjusting for comorbidities in a multivariate model, H2 FPEF score was significant predictor of new-onset CHF events both as continuous (HR=1.43, 95% CI: 1.05–1.96, P&lt;0.05) or categorical (H2 FPEF score ≥7) (HR=2.32, 95% CI: 1.17–4.63, P&lt;0.05) variables. The Kaplan-Meier estimates of CHF-free survival stratified by H2 FPEF status (≥7 or &lt;7) were shown in Figure.

Conclusion

H2 FPEF score provides prognostic information for new-onset CHF development in patients with AF.

Figure 1

Funding Acknowledgement

Type of funding source: None

Prognostic Value of Psoas Muscle Mass Index in Patients With Non‒ST-Segment‒Elevation Myocardial Infarction: A Prospective Observational Study

Background Muscle wasting is an important predictor of long-term outcome in patients with cardiovascular disease, but the prognostic value of muscle wasting in patients with non‒ST-segment‒elevation myocardial infarction is not established. The aim of this study is to investigate the prognostic value of muscle wasting, defined by psoas muscle mass index (PMI), in patients with non‒ST-segment‒elevation myocardial infarction. Methods and Results A total of 132 consecutive patients with non‒ST-segment‒elevation myocardial infarction were prospectively enrolled between 2015 and 2018. Primary end point was incidence of cardiovascular events including cardiovascular deaths, non-fatal myocardial infarction, or non-fatal stroke. Cross-sectional area of the psoas muscle at the L3 vertebral level was obtained by computed tomography and PMI was calculated. The median follow-up period was 2.4 years (interquartile range, 1.1-4.0 years). There were 45 cardiovascular events (34%) during the study periods. The optimal cutoff value of PMI to predict cardiovascular events was 772 mm2/m2, as assessed by receiver operating curve analysis. Patients with reduced PMI (PMI<772 mm2/m2) had significantly higher cardiovascular events than those with preserved PMI (PMI≥772 mm2/m2) (48% versus 21%; log-rank test P<0.001). Multivariate Cox proportional hazards model revealed that reduced PMI was a statistically significant predictor of cardiovascular events (hazard ratio, 3.30; 95% CI, 1.70-6.40; P<0.001). Conclusions Muscle wasting defined as PMI is a simple and useful objective marker to predict future cardiovascular outcome in patients with non‒ST-segment‒elevation myocardial infarction. Registration Information URL: https://www.umin.ac.jp/ctr/; Unique identifier: UMIN000013445.

Shortened red blood cell age in patients with end-stage renal disease who were receiving haemodialysis: a cross-sectional study

Background

The causes of anaemia in patients with end-stage renal disease include a relative deficiency in erythropoietin production and complex clinical conditions. We aimed to investigate the underlying mechanisms of anaemia in patients with end-stage renal disease who were undergoing maintenance dialysis by measuring erythrocyte creatine levels.

Methods

In a cross-sectional study, we evaluated 69 patients with end-stage renal disease who were receiving haemodialysis (n = 55) or peritoneal dialysis (n = 14). Erythrocyte creatine level, a quantitative marker of mean red blood cell (RBC) age, was measured.

Results

The mean RBC age was significantly shorter in the haemodialysis group than in the peritoneal dialysis group (47.7 days vs. 59.8 days, p < 0.0001), although the haemoglobin levels were comparable between the groups. A Spearman correlation coefficient analysis revealed that shortened RBC age positively correlated with transferrin saturation (r = 0.54), ferritin level (r = 0.47), and haptoglobin level (r = 0.39) but inversely related with reticulocyte (r = − 0.36), weekly doses of erythropoiesis-stimulating agents (ESAs; r = − 0.62), erythropoietin resistance index (r = − 0.64), and intradialytic ultrafiltration rate (r = − 0.32).

Conclusions

Shortened RBC age was observed in patients who were receiving maintenance haemodialysis and was associated with iron deficiency, greater haptoglobin consumption, higher ESA requirements, and poor erythropoietin responsiveness, as well as with greater intradialytic fluid extraction.

Loss of skeletal muscle mass predicts cardiac death in heart failure with a preserved ejection fraction but not heart failure with a reduced ejection fraction

Aims

Loss of skeletal muscle mass is an important determinant associated with poor long‐term prognosis in patients with acute decompensated heart failure (ADHF). However, limited evidence is available. This study investigated the prognostic value of the psoas muscle mass index (PMI) in patients with ADHF.

Methods and results

A total of 210 consecutive patients aged ≥60 years with ADHF were enrolled using a prospective database between 2015 and 2017. Primary endpoint was incidence of cardiac death. Cross‐sectional psoas muscle area at the L3 vertebral level was obtained by computed tomography, and PMI was calculated by height. Reduced PMI was defined as a PMI below the 25th sex‐specific percentile. Patients were also classified by their left ventricular ejection fraction (EF) as having either heart failure with a reduced ejection fraction (HFrEF, EF < 50%) or heart failure with a preserved ejection fraction (HFpEF, EF ≥ 50%). The median follow‐up period was 1.8 years. There were 44 cardiac deaths (21%) during the study period. Patients with reduced PMI had significantly higher cardiac death rates than those with preserved PMI (33% vs. 17%, log‐rank test P = 0.006). In subgroup analysis, HFpEF patients with reduced PMI had significantly higher cardiac death rates than those with preserved PMI (38% vs. 16%, log‐rank test P = 0.006); conversely, HFrEF patients had comparable cardiac death rates regardless of their PMI group (27% for reduced PMI vs. 18% for preserved PMI, log‐rank test P = 0.24). Multivariate Cox proportional hazards model revealed that patients with reduced PMI had a 2.3‐fold higher risk of cardiac death compared with patients with preserved PMI (95% confidence interval 1.23–4.42, P = 0.01).

Conclusions

Reduced PMI helps to predict long‐term outcome in patients with HFpEF but not HFrEF.

Heart Failure in Atrial Fibrillation - An Update on Clinical and Echocardiographic Implications

Atrial fibrillation (AF) is the most common sustained arrhythmia in adults and has unfavorable consequences such as stroke, heart failure (HF), and death. HF is the most common adverse event following AF and the leading cause of death. Therefore, identifying the association between AF and HF is important to establish risk stratification for HF in AF. Recent studies suggested that left atrial and ventricular fibrosis is an important link between AF and HF, and the prognostic impact may differ with respect to HF subtype, stratified with left ventricular ejection fraction (EF). Mortality risk in patients with concurrent AF and HF with reduced EF (HFrEF) appears slightly higher compared with those with concurrent AF and HF with preserved EF (HFpEF). On the other hand, the prognostic impact of HF in AF is similar between HFrEF and HFpEF. Further, left atrial size, as well as left atrial and left ventricular functional assessment, are reported to be useful for the prediction of HF in AF, incremental to the conventional risk factors. In this review, we focus on the epidemiological, pathophysiological, and prognostic associations between AF and HF, and review the clinical and echocardiographic predictors for HF in AF.

New CTO-Specific IVUS

The newer chronic total occlusion–specific intravascular ultrasound AnteOwl WR-based 3-dimensional wiring technique using the tip detection method allowed us easily to succeed in treating chronic total occlusion lesions that were previously unsuccessfully treated using Navifocus WR intravascular ultrasound. (Level of Difficulty: Advanced.)

Renoprotective effect of tolvaptan in patients with new-onset acute heart failure

AIMS

Although tolvaptan has been reported to prevent worsening renal function (WRF) in patients with advanced acute heart failure (AHF), evidence regarding the effect of tolvaptan on renal function in patients with new-onset AHF is not available. This study aimed to investigate the renoprotective effect of tolvaptan in patients hospitalized with new-onset AHF.

METHODS AND RESULTS

A total of 122 consecutive patients hospitalized with new-onset AHF between May 2015 and December 2018 were retrospectively evaluated. WRF was defined as an absolute increase in serum creatinine ≥0.3 mg/dL (≥26.4 μmol/L) within 48 h or a 1.5-fold increase in serum creatinine after hospitalization. The furosemide group (n = 75) and the tolvaptan add-on group (n = 47) were compared. The tolvaptan group consists of patients who received tolvaptan as an individual physicians' decision. The incidence of WRF was significantly lower in the tolvaptan add-on group (8.5%) than in the furosemide group (24.0%, P = 0.03). Multivariate logistic regression analysis revealed that tolvaptan treatment was an independent variable related to the prevention of WRF [odds ratio (OR), 0.20; 95% confidence interval (CI), 0.05-0.85]. Furthermore, subgroup analysis revealed a more favourable effect of tolvaptan in patients with serum creatinine ≥1.1 mg/dL on admission (OR, 0.23; 95% CI, 0.06-0.98) and an ejection fraction <50% (OR, 0.19; 95% CI, 0.04-0.90).

CONCLUSIONS

A lower incidence of WRF was observed in patients with new-onset AHF who were treated with the tolvaptan add-on therapy, specifically those with left ventricular systolic dysfunction and renal impairment on admission.

P196 Effect of tofogliflozin on systolic and diastolic cardiac function in type 2 diabetic patients

Funding Acknowledgements

None

Background

Recent studies have shown that sodium glucose cotransporter 2 (SGLT2) inhibitors have a favorable effect on cardiovascular events in diabetic patients. However, the underlying mechanism associated with favorable outcome has not been clearly identified.

Purpose

The purpose of this study was to investigate the effect of tofogliflozin, SGLT2 inhibitor, on systolic and diastolic cardiac function in patients with type 2 diabetes mellitus (T2DM).

Methods

We enrolled 26 consecutive T2DM out-patients on glucose-lowering drugs who initiated tofogliflozin and underwent echocardiogram before and ≥ 6 months after tofogliflozin administration. During this period, we also enrolled 162 T2DM out-patients taking other glucose-lowering drugs as a control group. Propensity score analysis was performed to match the patient characteristics. As a result, 40 patients (tofogliflozin group: 20 patients and control group: 20 patients) were finally used for analysis. Left ventricular systolic function was assessed by measuring 2D-echocardiographic left ventricular ejection fraction (LVEF) and diastolic cardiac function by pulsed wave Doppler derived early diastolic velocity (E/e’).

Results

There were no significant differences in patient characteristics and echocardiographic parameters at baseline. Follow-up E/e’ was significantly improved in tofogliflozin compared to control (11.7 ± 3.5 vs. 14.4 ± 4.5, p = 0.037). Moreover, the change in LVEF from baseline to follow up was 5.8± 7.2% in tofogliflozin group and 1.2 ± 6.9% in control group; difference significant: p = 0.047.

Conclusions

In addition to conventional oral glucose-lowering drugs, additional tofogliflozin administration had a favorable effect on left ventricular systolic and diastolic function in patients with T2DM.

Coronary artery calcification as a novel predictive marker of unstable coronary lesion in survivors of out-of-hospital cardiac arrest without ST-segment elevation

AIM

Acute myocardial infarction (AMI) is the leading cause of out-of-hospital cardiac arrest (OHCA). A highly predictive marker is needed to identify AMI in survivors of OHCA without ST-segment elevation because the appropriate indication for emergency coronary artery angiography in patients without ST-segment segment elevation has not been determined. Accordingly, the aim of this study was to elucidate the clinical significance of coronary artery calcification in identifying survivors of OHCA without ST-segment elevation who could benefit from emergency coronary artery angiography.

METHODS

Survivors of OHCA without ST-segment elevation with no obvious extra-cardiac cause who underwent emergency computed tomography and coronary artery angiography were enrolled. Unstable coronary lesion was diagnosed using coronary artery angiography, and presence of coronary artery calcification and coronary artery calcium score were evaluated by non-contrast, non-electrocardiography gated computed tomography.

RESULTS

Thirty of 100 consecutive survivors of OHCA were diagnosed to have unstable coronary lesion. Sensitivity and specificity of coronary artery calcification in identifying unstable coronary lesion were 87% and 60%, respectively. Multivariate logistic regression analysis revealed that coronary artery calcification was an independent predictor of unstable coronary lesion (odds ratio: 7.28, 95% confidence interval: 2.00-26.56, p < 0.001).

CONCLUSION

Evaluation of coronary artery calcification by computed tomography is useful in identifying patients with unstable coronary lesion who could benefit from emergency coronary artery angiography among survivors of OHCA without ST-segment elevation on post-resuscitation electrocardiography.

P5632Different impact of lesion length on fractional flow reserve in intermediate coronary lesions between each coronary artery

Background

Previous studies reported that lesion length was an important geometric parameter in addition to the degree of stenosis in the determinant of functional significance of coronary artery stenosis. Nevertheless, the optimal cutoff value of lesion length for predicting functional significance for each coronary artery has not yet been evaluated, though previous studies revealed that the cutoff value of minimum lumen diameter measured on coronary angiography (CAG) to predict fractional flow reserve (FFR) <0.80 is different for each coronary artery

Purpose

This study evaluated whether the impact of lesion length on functional significance is similar between each coronary artery for lesions with intermediate stenosis.

Methods

Patients with suspected coronary artery disease who had at least one intermediate coronary lesion (luminal diameter stenosis of 70 to 80% by visual estimation on CAG) and underwent FFR measurement for the evaluation of myocardial ischemia were evaluated. Quantitative coronary angiography analysis including percent diameter stenosis and lesion length was performed. FFR was measured as the ratio of the mean distal coronary artery pressure to the mean aortic pressure during maximal hyperemia induced by intravenous infusion of adenosine triphosphate (150 μg /kg/min). The area under the receiver operating characteristics (ROC) curve was estimated for the best cutoff value as a predictor of FFR value of ≤0.80 for each coronary artery.

Results

A total of 221 de novo lesions that underwent FFR measurement were enrolled. The average FFR value was 0.81±0.07. Although lesion length was similar among the lesions with an FFR >0.80 at different locations, the mean lesion length was significantly longer for lesions in the right coronary artery (RCA) with an FFR ≤0.80 than for those in the left anterior descending artery (LAD) and left circumflex artery (13.4±3.4 versus 8.6±3.1 versus 12.0±3.7 mm, p<0.001). ROC analysis demonstrated that the optimal cutoff value of lesion length for predicting an FFR ≤0.80 was 10.0 mm in the LAD (0.56 area under the curve, 48% sensitivity, 76% specificity), whereas 13.1 mm in the RCA (0.84 area under the curve, 67% sensitivity, 93% specificity) (Figure).

ROC analysis of LL for FFR≤0.80

Conclusions

A longer lesion length is required to achieve FFR<0.80 in the RCA than in the other arteries. This may suggest the low possibility of an FFR ≤0.80 when stenosis is focal and short in the RCA with stenosis of 70 to 80% by visual estimation on CAG.

P303Prognostic value of diastolic wall strain in patients with asymptomatic severe aortic stenosis

Background

Diastolic wall strain (DWS) has been reported to be associated with left ventricular (LV) stiffness and worse clinical outcomes. We sought to assess the utility of this new index for prediction of prognosis in asymptomatic patients with severe aortic stenosis (AS).

Methods

Asymptomatic severe AS patients [peak flow velocity (PFV) ≥4.0m/s, mean pressure gradient (mPG) ≥40mmHg, aortic valve area (AVA) ≤1.0cm2, or indexed AVA ≤0.6cm2/m2)] diagnosed between July 2007 and April 2016 were included in this study. Patients with significant mitral valve disease, posterior wall motion abnormality, prior cardiac surgery, hypertrophic cardiomyopathy, and LV ejection fraction <50% were excluded. DWS was calculated with a validated formula [DWS = (posterior wall thickness at end-systole − posterior wall thickness at end-diastole)/posterior wall thickness at end-systole]. All study patients were prospectively followed up to last visit or death until November 2017, and predictive value of all-cause death was assessed using Cox-proportional hazards modeling. Patients who underwent aortic valve replacement (AVR) during the study period were censored on the date of surgery.

Results

A total of 184 asymptomatic severe AS, 138 (age 76±9year-old, men 41%, PFV 3.9±1.0m/s, mPG 38±19mmHg, AVA 0.83±0.18cm2, indexed AVA 0.56±0.13cm2/m2) met all study criteria. Of whom, 43 (31%) underwent AVR and 28 (20%) died during a mean follow-up of 25±28months. In a multivariable model after adjusting for clinical and echocardiographic variables, advancing age (per10yrs; HR=2.19, 95% CI=1.19–4.03, P<0.05), history of hemodialysis (HR=4.31, 95% CI=1.30–14.35, P<0.05), and low-DWS (DWS <0.30) (HR=2.83, 95% CI=1.25–6.40, P<0.05) were independent predictors of all-cause death. In the Kaplan-Meier estimates of cumulative survival stratified by DWS status were shown (Figure).

The Kaplan-Meier estimates of survival

Conclusion

Low-DWS provides prognostic information in patients with asymptomatic severe AS.

3284Quantification of macrophage presence and identification of thin-cap fibroatheroma by optical coherence tomography image: histopathological validation study

Background

Intracoronary optical coherence tomography (OCT) is thought to be capable of identifying a vulnerable, rupture-prone plaque based on the presence of a thin-cap fibroatheroma (TCFA). Moreover, recent studies have reported that OCT may be able to identify macrophage infiltration of the fibrous cap, a key characteristic of vulnerable plaque.

Purpose

This study evaluated the accuracy of OCT image for characterizing TCFA and identifying macrophage infiltration in comparison with histopathology.

Methods

A total of 924 focal plaques in 206 coronary arteries from 78 autopsy hearts were examined to compare OCT and histological images. By histology, 16 plaques (1.7%) were classified as TCFAsthat contained a large necrotic core covered by a thin (<65μm) fibrous-cap. Correlating OCT-histological sections were identified and OCT-derived tissue property indexes named normalized standard deviation (NSD) and signal attenuation ratio were applied on the fibrous-cap to identify inflamed fibrous-cap defined as a macrophage percentage >10% by histology.

Results

With histology as standard, the sensitivity, specificity, and negative-predictive-value of TCFAs were extremely high (more than 90%). However, the positive-predictive-value of TCFAs was only 32%, which indicated a high proportion of false-positives. Most false-positive diagnoses of OCT for TCFAs contained large amounts of foam cell accumulations on luminal surface without necrotic core. Twelve of 16 fibrous-caps were considered as inflamed and the remaining 4 were non-inflamed on histology. However, no significant difference in NSD and signal attenuation ratio were identified between them. There was moderate correlation of the fibrous-cap thickness between OCT and histology (r2 = 0.41 and p<0.01).

Conclusions

OCT is a promising intracoronary imaging modality for differentiating tissue characteristics (fibrous, calcified, or lipid-rich plaque) and identifying TCFA. However, it is still challenging to precisely identify inflammation, fibrous-cap thickness, and necrotic core in the native coronary artery. Therefore, careful interpretation is required to assess coronary vulnerable plaque by OCT.

Acknowledgement/Funding

None

107Diagnostic accuracy of optical coherence tomography for the identification of in-stent fibroatheroma following stent implantation: an ex-vivo histological validation study

Background

Previous histopathological studies have demonstrated that new atherosclerotic formation within the neointima, called neoatherosclerosis, is one of the most important mechanisms leading to both very late in-stent restenosis and stent thrombosis after stent implantation. Therefore, to distinguish lipid-containing atherosclerotic neointima from other tissues using intracoronary imaging modalities is clinically important to prevent late stent failures.

Purpose

This study evaluated the diagnostic performance of optical coherence tomography (OCT) for the detection of “in-stent fibroatheroma” following stent implantation by comparing cross-sections of the model with the corresponding histological images.

Methods

Fifty stented coronary arteries from the 31 autopsy hearts were imaged by OCT. Coronary arterial histopathological specimens, all of which included more than 30% of %neointimal hyperplasia, were compared with the corresponding OCT cross-sections. Histological in-stent fibroatheroma was defined as neointima containing large necrotic core and inflammatory cells. OCT-derived in-stent fibroatheroma comprised a low-intensity tissue containing a poorly delineated region with invisible stent strut behind low signal intensity.

Results

A total of 122 OCT cross-sections were compared with histological images. OCT examination revealed that 24 images (20%) contained low-intensity tissue inside the neointima. Of those, 5 images, in which stent strut behind low signal intensity was invisible, were diagnosed as OCT-derived in-stent fibroatheroma (4%) (Figure A). By histological analysis, only 4 images were classified as in-stent fibroatheroma (3%) (Figure B). With histology as the gold standard, the sensitivity, specificity, positive predictive value, negative predictive value, and overall diagnostic accuracy for OCT-derived in-stent fibroatheroma were 100%, 99%, 80%, 100%, and 99%, respectively. The only histological finding underlying the false-positive-diagnosis of OCT-derived in-stent fibroatheroma was foam cells accumulation without necrotic core on the neointimal surface (Figure C and D). Most tissue that showed low-intensity tissue with visible stent strut by OCT contained proteoglycan matrix and organized thrombus in the absence of an underlying necrotic core.

Coregistration of OCT with histology

Conclusion

This study showed the potential capability of OCT based on the visualization of stent struts behind low-intensity regions for discriminating in-stent fibroatheroma from other neointimal tissues following stent implantation.

Cardiac Rupture Due to Reinfarction in the Early Phase of Apical Myocardial Infarction

A 72-year-old woman with hypertension, dyslipidemia, and diabetes mellitus presented to our hospital because of the sudden onset of chest pain. Emergency coronary angiography showed acute occlusion of the distal left anterior descending artery and coronary intervention with a drug-eluting stent was performed. Sudden cardiopulmonary arrest occurred on the sixth day of hospitalization, but coronary angiography showed no remarkable progression of the coronary artery diseases, including the site of stent implantation. An autopsy revealed that the cause of the sudden death was apical free wall rupture. In addition, the different timing of acute and sub-acute infarct findings were observed in the apical wall by histology, which indicated cardiac rupture was due to reinfarction at early phase of apical acute myocardial infarction. Although the rate of mechanical complications, including cardiac rupture, is decreasing in the era of primary coronary intervention, in addition to the well-known risk factors of cardiac rupture, the reinfarction of the culprit myocardial site in the early phase of acute myocardial infarction was considered as a possible risk factor of cardiac rupture.

Clinical Implication of Coronary Artery Calcium Score in Survivors of Out-of-Hospital Cardiac Arrest

Background: The aim of this study was to evaluate the clinical ability of coronary artery calcium (CAC) score to identify acute myocardial infarction (AMI) in survivors of out-of-hospital cardiac arrest (OHCA).

Methods and Results: We studied 180 consecutive survivors of OHCA who underwent immediate non-contrast computed tomography (CT) and coronary angiography. Seventy-one patients had ST elevation or left bundle branch block (LBBB; group 1) and 109 patients did not have ST elevation or LBBB (group 2) on post-resuscitation electrocardiogram (ECG). CAC score was significantly higher in AMI compared with non-AMI in groups 1 and 2. The optimal cut-off of CAC score to identify AMI was 11.5 (sensitivity, 80%; specificity, 71%) in group 1, and 27.4 (sensitivity, 80%; specificity, 76%) in group 2. On multivariate analysis, CAC score was the strongest predictive marker of AMI (OR, 10.91; 95% CI: 6.00–25.97). In addition, CAC score was an independent predictor of 30-day survival (OR, 0.38; 95% CI: 0.15–0.95).

Conclusions: Evaluation of CAC is a useful method to identify AMI in survivors of OHCA, regardless of ST changes on post-resuscitation ECG.

Type 1 and type 2 iodothyronine deiodinases in the thyroid gland of patients with huge goitrous Hashimoto's thyroiditis

PURPOSE

The serum free triiodothyronine (FT3)/free thyroxine (FT4) ratio in patients with huge goitrous Hashimoto's thyroiditis (HG-HT) is relatively high. We investigated the cause of high FT3/FT4 ratios.

METHODS

We measured the serum FT3, FT4, and thyrotropin (TSH) levels of seven patients with HG-HT who had undergone a total thyroidectomy. Eleven patients with papillary thyroid carcinoma served as controls. The activities and mRNA levels of type 1 and type 2 iodothyronine deiodinases (D1 and D2, respectively) were measured in the thyroid tissues of HG-HT and perinodular thyroid tissues of papillary thyroid carcinoma.

RESULTS

The TSH levels in the HG-HT group were not significantly different from those of the controls. The FT4 levels in the HG-HT group were significantly lower than those of the controls, whereas the FT3 levels and FT3/FT4 ratios were significantly higher in the HG-HT group. The FT3/FT4 ratios in the HG-HT group who had undergone total thyroidectomy and received levothyroxine therapy decreased significantly to normal values. Both the D1 and D2 activities in the thyroid tissues of the HG-HT patients were significantly higher than those of the controls. However, the mRNA levels of both D1 and D2 in the HG-HT patients' thyroid tissues were comparable to those of the controls. Interestingly, there were significant correlations between the HG-HT patients' D1 and D2 activities, and their thyroid gland volume or their FT3/FT4 ratios.

CONCLUSIONS

Our results indicate that increased thyroidal D1 and D2 activities may be responsible for the higher serum FT3/FT4 ratio in patients with HG-HT.

The unstable pacing thresholds of the leadless transcatheter pacemaker affected by body positions in subacute phase after implant

Background

If the threshold at implant of leadless transcatheter pacemakers (LTPs) is less than 2.0 V, pacing thresholds reportedly decrease significantly by 1 month and maintain an optimal value of less than 1.0 V by 6 months.

Case summary

We report a case series of two patients with unstable pacing thresholds of the LTPs in the subacute phase after implant. The first patient (77-year-old man) was implanted an LTP for sick sinus syndrome. At that time of implant, the pacing threshold was 0.9 V at 0.24 ms. At 1 week and 1 month later, the threshold had increased to more than 2.0 V at 0.24 ms. We investigated the trend data for the week and found variations in the threshold. The second patient (81-year-old man) was implanted an LTP for bradycardia and atrial fibrillation. The pacing threshold at implantation was 0.63 V at 0.24 ms. One week later, the threshold had increased in supine position and decreased in sitting position. The trend data for the week were fluctuating greatly.

Discussion

The pacing threshold may increase to more than 2.0 V with significant fluctuation on assessment at 1 week and 1 month after implantation in association with changes in body position, even though we confirmed a stable threshold at implant. If an increased threshold is observed, it is necessary to check the trend data and threshold in each body position.

Serial optical coherence tomography and angioscopic assessments of 10-year in-stent restenosis of Cypher sirolimus-eluting stent treated with drug-coated balloon angioplasty

The drug-coated balloon (DCB) angioplasty is considered a standard therapeutic option for in-stent restenosis. In the present case, we observed high-intensity spots on optical coherence tomography (OCT) and bright spots on coronary angioplasty (CAS) immediately after DCB angioplasty. The superficial high-intensity area on OCT presumably corresponded with the bright spots on CAS. The high-intensity superficial regions were thought to represent an iopromide/paclitaxel mixture. The present serial observation demonstrated that the eluted drugs remained for at least 2 months but disappeared within 6 months. At the site where we observed the drugs, neointimal growth was successfully inhibited and stabilized at the 6-month follow-up. The association of eluted drugs after DCB angioplasty with consequent neointimal growth is of scientific interest. Further prospective imaging studies with a large sample size are warranted to clarify this association.

Early vessel healing after implantation of biodegradable-polymer and durable-polymer drug-eluting stent: 3-month angioscopic evaluation of the RESTORE registry

The purpose of this study was to evaluate the vessel healing status 3 months after stent implantation of bioresorbable-polymer drug-eluting stents (BP-DESs) in comparison with durable-polymer DESs (DP-DESs) by angioscopy. Study design was a single-center all-comer prospective cohort study: the RESTORE registry (UMIN000033009). All patients who received successful angioscopic examination at planned 3-month follow-up after the DES implantation in the native coronary artery were enrolled. We evaluated main, maximum, minimum strut coverage grades and coverage heterogeneity score defined as a difference between maximum and minimum coverage grades. All lesions were divided into three segments: proximal, mid, and distal segments. A total of 108 patients (66.6 ± 10 years) with 124 lesions were analyzed (BP-DES 57 patients 61 lesions 226 segments vs. DP-DES 57 patients 63 lesions 203 segments; six patients had both BP-DES and DP-DES). Patient and lesion demographics, procedural characteristics were well balanced. Main coverage grade (mean ± standard error; 1.08 ± 0.02 vs. 1.05 ± 0.03, p = 0.354) and minimum coverage grade (1.00 ± 0.00 vs. 1.00 ± 0.00, p > 0.999) were not significantly different between BP-DES and DP-DES groups. Maximum coverage grade was significantly higher in the BP-DES than in the DP-DES (1.45 ± 0.04 vs. 1.35 ± 0.04, p = 0.049). Coverage heterogeneity score did not differ between BP-DES and DP-DES groups (1.05 ± 0.07 vs. 0.90 ± 0.07, p = 0.162). At 3-month follow-up, the current BP-DES had higher maximum stent coverage than the contemporary DP-DES, while main and minimum coverage grades and heterogeneity of the neointimal coverage were comparable. Further prospective randomized trials should be conducted to evaluate the clinical significance of the present imaging results.