Kiyotaka Hao

Increased Coronary Perivascular Adipose Tissue Volume in Patients With Vasospastic Angina

BACKGROUND Recent studies have suggested that coronary perivascular adipose tissue (PVAT) impairs coronary vasomotion, so we examined whether PVAT is increased at the spastic coronary segment in patients with vasospastic angina (VSA). METHODSANDRESULTS PVAT volume in the left anterior descending (LAD) coronary arteries on CT coronary angiography was significantly increased in 48 VSA patients with LAD spasm compared with 18 controls (30.7±2.0 vs. 21.0±3.2 cm(3), P=0.01), whereas that of total epicardial adipose tissue was comparable between the 2 groups. CONCLUSIONS The results suggested an important role of PVAT in the pathogenesis of coronary spasm. (Circ J 2016; 80: 1653-1656).

Enhanced Adventitial Vasa Vasorum Formation in Patients With Vasospastic Angina: Assessment With OFDI.

Coronary artery spasm plays important roles in the pathogenesis of a wide range of ischemic heart disease. Recent studies have demonstrated that coronary spasm is frequently noted in Caucasians as in Asians [(1)][1]. We previously demonstrated that vascular smooth muscle cell hypercontraction

Accuracy of Optical Frequency Domain Imaging for Evaluation of Coronary Adventitial Vasa Vasorum Formation After Stent Implantation in Pigs and Humans – A Validation Study –

BACKGROUND Coronary adventitia harbors a wide variety of components, such as inflammatory cells and vasa vasorum (VV). Adventitial VV initiates the development of coronary artery diseases as an outside-in supply route of inflammation. We have recently demonstrated that drug-eluting stent implantation causes the enhancement of VV formation, with extending to the stent edges in the porcine coronary arteries, and also that optical frequency domain imaging (OFDI) is capable of visualizing VV in humans in vivo. However, it remains to be fully validated whether OFDI enables the precise measurement of VV formation in pigs and humans. METHODS AND RESULTS In the pig protocol, a total of 6 bare-metal stents and 12 drug-eluting stents were implanted into the coronary arteries, and at 1 month, the stented coronary arteries were imaged by OFDI ex vivo. OFDI data including the measurement of VV area at the stent edge portions were compared with histological data. There was a significant positive correlation between VV area on OFDI and that on histology (R=0.91, P<0.01). In the human protocol, OFDI enabled the measurement of the VV area at the stent edges after coronary stent implantation in vivo. CONCLUSIONS These results provide the first direct evidence that OFDI enables the precise measurement of the VV area in coronary arteries after stent implantation in pigs and humans.

Exercise training upregulates nitric oxide synthases in the kidney of rats with chronic heart failure.

There is an interaction between heart and kidney diseases, which is a condition termed cardiorenal syndrome. Exercise training has cardioprotective effects, involving upregulation of endothelial (e) nitric oxide synthase (NOS) in the cardiovascular system. However, the effects of exercise training on NOS in the kidney with heart disease are unknown. The aim of the present study was to investigate whether exercise training upregulates NOS in the kidney, left ventricle and aorta of rats with chronic heart failure (CHF). Male Sprague‐Dawley rats underwent left coronary artery ligation (LCAL) to induce CHF and were randomly assigned to sedentary or treadmill exercise groups 4 weeks after LCAL. Three days after exercising for 4 weeks, urine samples were collected for 24 h and blood samples were collected following decapitation. Nitric oxide synthase activity and protein expression were examined. Significant interactions between CHF and exercise training were observed on parameters of cardiac and renal function. Exercise training improved cardiac function, decreased plasma B‐type natriuretic peptide levels, decreased urinary albumin excretion and increased creatinine clearance in CHF rats. Nitric oxide synthase activity, eNOS expression and neuronal (n) NOS expression were significantly decreased in the left ventricle and kidney of CHF rats. Exercise training significantly increased NOS activity and eNOS and nNOS expression. Upregulation of NOS in the kidney and left ventricle may contribute, in part, to the renal and cardiac protective effects of exercise training in cardiorenal syndrome in CHF rats.

Clinical Characteristics of Patients With Acute Myocardial Infarction Who Did Not Undergo Primary Percutaneous Coronary Intervention – Report From the MIYAGI-AMI Registry Study –

BACKGROUND In the current era of primary percutaneous coronary intervention (PCI), some patients with acute myocardial infarction (AMI) still do not undergo primary PCI. METHODSANDRESULTS To examine the clinical characteristics of AMI patients who did not undergo primary PCI, we analyzed patients enrolled between 2002 and 2010 in the MIYAGI-AMI Registry Study, in which all AMI patients in the Miyagi prefecture have been prospectively registered. Among a total of 8,640 patients, 1,879 (21.7%) did not undergo primary PCI and their in-hospital mortality was significantly worse compared with those who did (21.4% vs. 6.4%, P<0.01). Multivariate analysis demonstrated that female sex was significantly associated with non-performance of primary PCI [odds ratio (95% confidence interval): 1.40 (1.22-1.61), P<0.001], along with age [1.01 (1.01-1.02), P<0.001] and heart failure on admission [2.69 (2.29-3.16), P<0.001]. When dividing by age, the non-performance rate of primary PCI in females showed a U-shaped prevalence, whereas it simply increased with aging in males. Importantly, female patients aged <80 years had a significantly higher non-performance rate of primary PCI compared with male patients, regardless of the severity of AMI. CONCLUSIONS These results indicate that in the current PCI era, various factors, including aging, heart failure on admission and sex differences, are associated with non-performance of primary PCI, which remain to be resolved in order to further improve critical care of AMI.

Plasma concentration of serotonin is a novel biomarker for coronary microvascular dysfunction in patients with suspected angina and unobstructive coronary arteries

Aims Although the importance of coronary microvascular dysfunction (CMD) has been emerging, reliable biomarkers for CMD remain to be developed. We examined the potential usefulness of plasma concentration of serotonin to diagnose CMD in patients with suspected angina and unobstructive coronary arteries. Methods and results We enrolled 198 consecutive patients (M/F 116/82, 60.2 ± 13.3 years old) who underwent acetylcholine provocation test and measured plasma serotonin concentration. Coronary microvascular dysfunction was defined as myocardial lactate production without or prior to the occurrence of epicardial coronary spasm during acetylcholine provocation test. Although no statistical difference in plasma concentration of serotonin [median (inter-quartile range) nmol/L] was noted between the vasospastic angina (VSA) and non-VSA groups [6.8 (3.8, 10.9) vs. 5.1 (3.7, 8.4), P = 0.135], it was significantly higher in patients with CMD compared with those without it [7.7 (4.5, 14.2) vs. 5.6 (3.7, 9.3), P = 0.008]. Among the four groups classified according to the presence or absence of VSA and CMD, serotonin concentration was highest in the VSA with CMD group. Importantly, there was a positive correlation between plasma serotonin concentration and baseline thrombolysis in myocardial infarction frame count (P = 0.001), a marker of coronary vascular resistance. The classification and regression trees analysis showed that plasma serotonin concentration of 9.55 nmol/L was the first discriminator to stratify the risk for the presence of CMD. In multivariable analysis, serotonin concentration greater than the cut-off value had the largest odds ratio in the prediction of CMD [odds ratio (95% confidence interval) 2.63 (1.28–5.49), P = 0.009]. Conclusions Plasma concentration of serotonin may be a novel biomarker for CMD in patients with angina and unobstructive coronary arteries.

Focal Vasa Vasorum Formation in Patients With Focal Coronary Vasospasm – An Optical Frequency Domain Imaging Study –

Coronary adventitia has attracted much attention as a source of inflammation because it harbors nutrient blood vessels, oronary artery spasm plays important roles in the pathogenesis of a wide range of ischemic heart disease, not only in vasospastic angina (VSA) but also in other forms of ischemic heart disease.1 Although VSA is believed to be more prevalent in Asian compared with Caucasian subjects,2 it has been recently suggested that the prevalence of VSA could be similar in both populations.3 Thus, coronary spasm is an emerging issue in the world. Furthermore, given C

Prognostic impacts of Rho-kinase activity in circulating leucocytes in patients with vasospastic angina

Aims Rho-kinase activity in circulating leucocytes is a useful biomarker for diagnosis and disease activity assessment of vasospastic angina (VSA). The present study aimed to examine the long-term prognostic impact of Rho-kinase activity in circulating leucocytes in VSA patients. Methods and results We prospectively enrolled 174 consecutive patients with VSA and 50 non-VSA patients, in whom we measured Rho-kinase activity in circulating leucocytes, and they were followed for a median of 16 months. The primary endpoint was cardiac events including cardiac death, non-fatal myocardial infarction, and hospitalization for unstable angina. During the follow-up period, cardiac events occurred in 10 VSA patients (5.7%) but in none of the non-VSA patients. When we divided VSA patients into two groups by a median value of their Rho-kinase activity, the Kaplan-Meier survival analysis showed a significantly worse prognosis in VSA patients with high Rho-kinase activity compared with those with low activity or non-VSA patients (log-rank; P < 0.05, respectively). Receiver-operating characteristic curve analysis showed that Rho-kinase activity value of 1.24 was the best cut-off level to predict cardiac events in VSA patients, and multivariable analysis showed that a value above the cut-off point had the largest hazard ratio to predict poor outcome in VSA patients [hazard ratio (95% confidence interval) 11.19 (1.41-88.95); P = 0.022]. Importantly, combination of the Japanese Coronary Spasm Association risk score and Rho-kinase activity significantly improved the prognostic impact in VSA patients as compared with either alone. Conclusion Rho-kinase activity in circulating leucocytes is useful for prognostic stratification of VSA patients.

Factors influencing the occurrence of cardiopulmonary arrest in the Great East Japan Earthquake disaster

Background: We have previously reported that the Great East Japan Earthquake increased the occurrence of cardiopulmonary arrest (CPA). In this study, we assessed the factors influencing the occurrence of CPA of presumed cardiac origin in the Disaster. Methods and Results: We enrolled all patients with CPA of presumed cardiac origin by using the ambulance transport records database of Miyagi Prefecture, the center of the Disaster area, from February 11 to June 30 of 2008-2011 (n=2,534) and compared the weekly occurrences in 2011 with those in the previous 3 years. In the whole patients, the weekly occurrence of CPA was significantly increased with the bimodal peaks noted in the first 2 weeks after the Earthquake (March 11, 2011) and in the week just after the largest aftershock (April 7, 2011) compared with the previous 3 years. Sub-group analyses for sex, age ( Conclusions: These results indicate that the increase in the occurrence of CPA after the Earthquake was influenced by sex, age, and residence, providing a clue to reduce CPA in future disasters.

Age-Specific Trends in the Incidence and In-Hospital Mortality of Acute Myocardial Infarction Over 30 Years in Japan - Report From the Miyagi AMI Registry Study -

BACKGROUND We are now facing rapid population aging in Japan, which will affect the actual situation of cardiovascular diseases. However, age-specific trends in the incidence and mortality of acute myocardial infarction (AMI) in Japan remain to be elucidated.Methods and Results:We enrolled a total of 27,220 AMI patients (male/female 19,818/7,402) in our Miyagi AMI Registry during the past 30 years. We divided them into 4 age groups (≤59, 60-69, 70-79 and ≥80 years) and examined the temporal trends in the incidence and in-hospital mortality of AMI during 3 decades (1985-1994, 1995-2004 and 2005-2014). Throughout the entire period, the incidence of AMI steadily increased in the younger group (≤59 years in both sexes), while in the elderly groups (≥70 years in both sexes), the incidence significantly decreased during the last decade (all P<0.01). In-hospital cardiac mortality significantly decreased during the first 2 decades in elderly groups of both sexes (all P<0.01), whereas no further improvement was noted in the last decade irrespective of age or sex, despite improved critical care of AMI. CONCLUSIONS These results provide the novel findings that the incidence of AMI has been increasing in younger populations and decreasing in the elderly, and that improvement in the in-hospital mortality of AMI may have reached a plateau in all age groups in Japan.