Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Kenshi Hirayama is active.

Publication


Featured researches published by Kenshi Hirayama.


Circulation | 2017

Nutrition Status Predicts Severity of Vascular Calcification in Non-Dialyzed Chronic Kidney Disease

Kazuhiro Harada; Susumu Suzuki; Hideki Ishii; Kenshi Hirayama; Toshijiro Aoki; Yohei Shibata; Yosuke Negishi; Takuya Sumi; Kazuhiro Kawashima; Ayako Kunimura; Yosuke Tatami; Toshiki Kawamiya; Dai Yamamoto; Ryota Morimoto; Yoshinari Yasuda; Toyoaki Murohara

BACKGROUND Vascular calcification is a major complication in chronic kidney disease (CKD) that increases the risk of adverse clinical outcomes. Geriatric nutritional risk index (GNRI) is a simple nutritional assessment tool that predicts poor prognosis in elderly subjects. The purpose of the present study was to evaluate the correlation between GNRI and severity of vascular calcification in non-dialyzed CKD patients.Methods and Results:We enrolled 323 asymptomatic CKD patients. To evaluate abdominal aortic calcification (AAC), we used aortic calcification index (ACI) determined on non-contrast computed tomography. The patients were divided into three groups according to GNRI tertile. Median ACI significantly decreased with increasing GNRI tertile (15.5%, 13.6%, and 7.9%, respectively; P=0.001). On multivariate regression analysis GNRI was significantly correlated with ACI (β=-0.15, P=0.009). We also investigated the combination of GNRI and C-reactive-protein (CRP) for predicting the severity of AAC. Low GNRI and high CRP were significantly associated with severe AAC, compared with high GNRI and low CRP (OR, 4.07; P=0.004). CONCLUSIONS GNRI was significantly associated with AAC in non-dialyzed CKD patients.


Journal of Cardiology | 2017

Impact of Geriatric Nutritional Risk Index on cardiovascular outcomes in patients with stable coronary artery disease

Ayako Kunimura; Hideki Ishii; Tadayuki Uetani; Toshijirou Aoki; Kazuhiro Harada; Kenshi Hirayama; Yosuke Negishi; Yohei Shibata; Takuya Sumi; Kazuhiro Kawashima; Yosuke Tatami; Toshiki Kawamiya; Dai Yamamoto; Susumu Suzuki; Tetsuya Amano; Toyoaki Murohara

BACKGROUND The association between malnutrition and cardiovascular prognosis in patients with stable coronary artery disease remains unclear. The aim of this study was to evaluate the association between Geriatric Nutritional Risk Index (GNRI), a simple tool to assess nutritional risk, and long-term outcomes after elective percutaneous coronary intervention (PCI). METHODS This study consisted of 802 patients (age, 70±10 years, male, 69%) who underwent elective PCI. GNRI was calculated at baseline as follows: GNRI=[14.89×serum albumin (g/dl)+[41.7×(body weight/body weight at body mass index of 22)]]. Patients were then divided into three groups as previously reported: GNRI <92, 92 to ≤98, and >98. The endpoint of this study was the composite of cardiac death or non-fatal myocardial infarction. RESULTS During a median follow-up period of 1568 days, 56 cardiac events occurred. Using Kaplan-Meier analysis, the 4-year event-free rates were found to be 79% for GNRI <92, 90% for GNRI 92 to ≤98, and 97% for GNRI >98 (log-rank test p<0.001). GNRI <92 and GNRI 92 to ≤98 showed 6.76-fold [95% confidence interval (CI) 3.13-14.56, p<0.001] and 3.03-fold (HR 3.03, 95%CI 1.36-6.78, p=0.007) increase in the incidences of cardiac death or non-fatal myocardial infarction compared with GNRI >98 after adjusting for confounding factors. CONCLUSION GNRI significantly associated with cardiac events after elective PCI. Further studies should be performed to establish appropriate therapeutic strategies for this vulnerable patient group.


Geriatrics & Gerontology International | 2017

Correlations between geriatric nutritional risk index and peripheral artery disease in elderly coronary artery disease patients.

Toshiki Kawamiya; Susumu Suzuki; Hideki Ishii; Kenshi Hirayama; Kazuhiro Harada; Yohei Shibata; Yosuke Tatami; Shingo Harata; Kazuhiro Kawashima; Ayako Kunimura; Yohei Takayama; Yusaku Shimbo; Naohiro Osugi; Dai Yamamoto; Tomoyuki Ota; Chikao Kono; Toyoaki Murohara

Malnutrition is associated with the development of atherosclerosis and an increased risk of cardiovascular mortality in elderly patients. The present study aimed to investigate the association between the Geriatric Nutritional Risk Index (GNRI), a simple nutritional assessment tool, and the prevalence of peripheral artery disease (PAD) in elderly coronary artery disease patients.


Circulation | 2017

Decreased Serum Albumin Predicts Bleeding Events in Patients on Antiplatelet Therapy After Percutaneous Coronary Intervention

Yosuke Tatami; Hideki Ishii; Toshijiro Aoki; Kazuhiro Harada; Kenshi Hirayama; Yohei Shibata; Takuya Sumi; Yosuke Negishi; Kazuhiro Kawashima; Ayako Kunimura; Toshiki Kawamiya; Dai Yamamoto; Susumu Suzuki; Toyoaki Murohara

BACKGROUND Antiplatelet therapy (APT) after percutaneous coronary intervention (PCI) prevents ischemic events with increased risk of bleeding. Little is known about the relationship between hypoalbuminemia and bleeding risk in patients receiving APT after PCI. This study investigated the association between serum albumin level and bleeding events in this population.Methods and Results:We enrolled 438 consecutive patients who were prescribed dual APT (DAPT; aspirin and thienopyridine) beyond 1 month after successful PCI without adverse events. The patients were divided into 3 groups according to serum albumin tertile: tertile 1, ≤3.7 g/dL; tertile 2, 3.8-4.1 g/dL; and tertile 3, ≥4.2 g/dL. Adverse bleeding events were defined as Bleeding Academic Research Consortium criteria types 2, 3, and 5. During the median follow-up of 29.5 months, a total of 30 adverse bleeding events were observed. Median duration of DAPT was 14 months. The tertile 1 group had the highest risk of adverse bleeding events (event-free rate, 83.1%, 94.3% and 95.8%, respectively; P<0.001). On Cox proportional hazards modeling, serum albumin independently predicted adverse bleeding events (HR, 0.10, 95% CI: 0.027-0.39, P=0.001, for tertile 3 vs. tertile 1). CONCLUSIONS Decreased serum albumin predicted bleeding events in patients with APT after PCI.


Clinica Chimica Acta | 2018

Balance between angiogenic and anti-angiogenic isoforms of VEGF-A is associated with the complexity and severity of coronary artery disease

Yohei Shibata; Ryosuke Kikuchi; Hideki Ishii; Susumu Suzuki; Kazuhiro Harada; Kenshi Hirayama; Atsuo Suzuki; Yosuke Tatami; Kazuhisa Kondo; Toyoaki Murohara

INTRODUCTION Assessing the complexity of coronary artery disease (CAD) is clinically important. Vascular endothelial growth factor A (VEGF-A) is a powerful and the most important regulator of angiogenesis. It has been reported that the anti-angiogenic isoform of VEGF-A (VEGF-A165b) inhibits angiogenesis. The purpose of this study was to evaluate the relationship between the complexities of CAD using the Syntax score (SS) and the levels of circulating total VEGF-A or VEGF-A165b. METHODS A total of 268 patients who underwent percutaneous coronary intervention (PCI) were enrolled. Of these, 73 patients without acute coronary syndrome or previous revascularization were included in this study. These subjects were divided into two groups according to the SS. Circulating total VEGF-A and VEGF-A165b levels were measured using an enzyme-linked immunosorbent assay. RESULTS Circulating levels of total VEGF-A were significantly higher in the SS>22 (high SS) group than in the SS≤22 (low SS) group (p=0.018). Moreover, the ratio of VEGF-A165b to total VEGF-A was significantly lower for the high SS group (p=0.004). The levels of total VEGF-A independently predicted high SS after adjusting for other significant variables among patients who underwent PCI (odds ratio, 1.004; 95% CI, 1.001 to 1.006; p=0.01). CONCLUSIONS These data indicated that high SS was associated with circulating levels of total VEGF-A and the ratio of VEGF-A165b to total VEGF-A in patients with complex CAD.


Journal of Atherosclerosis and Thrombosis | 2017

Predictive Value of Aortic Valve Calcification for Periprocedural Myocardial Injury in Patients Undergoing Percutaneous Coronary Intervention

Yohei Shibata; Hideki Ishii; Susumu Suzuki; Akihito Tanaka; Yosuke Tatami; Shingo Harata; Tomoyuki Ota; Yusaku Shimbo; Yohei Takayama; Ayako Kunimura; Kenshi Hirayama; Kazuhiro Harada; Naohiro Osugi; Toyoaki Murohara

Aims: Previous studies have shown that aortic valve calcification (AVC) was associated with cardiovascular events and mortality. On the other hand, periprocedural myocardial injury (PMI) in percutaneous coronary intervention (PCI) is a well-known predictor of subsequent mortality and poor clinical outcomes. The purpose of the study was to assess the hypothesis that the presence of AVC could predict PMI in PCI. Methods: This study included 370 patients treated with PCI for stable angina pectoris. AVC was defined as bright echoes > 1 mm on one or more cusps of the aortic valve on ultrasound cardiography (UCG). PMI was defined as an increase in high-sensitivity troponin T level of > 5 times the upper normal limit (> 0.070 ng/ml) at 24 hours after PCI. Results: AVC was detected in 45.9% of the patients (n = 170). The incidence of PMI was significantly higher in the patients with AVC than in those without AVC (43.5% vs 21.0%, p < 0.001). The presence of AVC independently predicted PMI after adjusting for other significant variables (odds ratio 2.26, 95% confidence interval 1.37–3.74, p = 0.002). Other predictors were male sex, age, estimated glomerular filtration rate, and total stent length. Furthermore to predict PMI, adding AVC to the established risk factors significantly improved the area under the receiver operating characteristic curves, from 0.68 to 0.72, of the PMI prediction model (p = 0.025). Conclusion: The presence of AVC detected in UCG could predict the incidence of PMI.


Clinical Therapeutics | 2017

Impact of Paradoxical Decrease in High-density Lipoprotein Cholesterol Levels After Statin Therapy on Major Adverse Cardiovascular Events in Patients with Stable Angina Pectoris

Kenshi Hirayama; Tomoyuki Ota; Kazuhiro Harada; Yohei Shibata; Yosuke Tatami; Shingo Harata; Kazuhiro Kawashima; Ayako Kunimura; Yusaku Shimbo; Yohei Takayama; Toshiki Kawamiya; Dai Yamamoto; Naohiro Osugi; Susumu Suzuki; Hideki Ishii; Toyoaki Murohara

PURPOSE Statin therapy usually increases HDL-C levels. However, a paradoxical decrease in HDL-C levels after statin therapy is often seen in clinical settings. The relationship between a paradoxical decrease in HDL-C levels after statin therapy and adverse cardiovascular events in patients with stable angina pectoris (SAP) is not well understood. The purpose of this study was to analyze the relationship between paradoxical HDL-C decreases after statin therapy and major adverse cardiovascular events (MACEs) in patients undergoing percutaneous coronary intervention (PCI) for SAP. METHODS Between January 2006 and March 2015, 867 patients underwent PCI for SAP. Of them, we enrolled 209 patients who were newly started on statin therapy before PCI. We excluded patients who had started statin therapy earlier than 6 months before PCI, patients who had not started statin therapy after PCI, and patients who were diagnosed with acute coronary syndrome. They were divided into 2 groups according to the change in their HDL-C levels between baseline and 6 to 9 months after the index PCI: decreased HDL group after statin treatment (80 patients) and increased HDL group (129 patients). The primary end points were MACEs defined as a composite of all-cause death, nonfatal acute myocardial infarction, and target vessel revascularization (TVR). FINDINGS Using Kaplan-Meier analysis, the 7-year event rate for composite MACEs in the decreased HDL group was found to be higher than that for the increased HDL group (38% versus 24%, log-rank P = 0.02). TVR occurred more frequently in the decreased HDL group than in the increased HDL group (32% versus 12%, log-rank P = 0.01). With the use of multivariate analysis, changes in HDL-C levels after statin therapy indicated a significant inverse association with the increased risk of MACEs, (hazard ratio [HR] = 0.94; 95% CI, 0.92-0.97; P < 0.01). The incidence of MACEs was more strongly associated with ΔHDL than with ΔLDL. Moreover, BMS usage also independently predicted MACEs (HR = 2.18; 95% CI, 1.14-4.17; P < 0.01). IMPLICATIONS A paradoxical decrease in HDL-C levels after statin therapy might be a risk factor for MACEs, especially TVR, in patients with SAP.


IJC Heart & Vasculature | 2018

Association between the ratio of anti-angiogenic isoform of VEGF-A to total VEGF-A and adverse clinical outcomes in patients after acute myocardial infarction

Kazuhiro Harada; Ryosuke Kikuchi; Hideki Ishii; Yohei Shibata; Susumu Suzuki; Akihito Tanaka; Atsuo Suzuki; Kenshi Hirayama; Toyoaki Murohara

Background Vascular endothelial growth factor-A (VEGF-A) promotes neovascularization and is attracting considerable attention as a remarkable risk factor in patients after acute myocardial infarction (AMI). In contrast, the association between VEGF-A165b, which is the main anti-angiogenic isoform of VEGF-A, and adverse clinical outcomes after AMI remains unclear. The present study aimed to investigate the association between serum VEGF-A165b and major adverse cardiac and cerebrovascular events (MACCEs) after percutaneous coronary intervention (PCI) for AMI. Methods We evaluated 23 patients with AMI who underwent primary percutaneous coronary intervention. VEGF-A and VEGF-A165b levels were measured on admission (day 1) and at days 3, 7, and 30 after PCI. Results The levels of total VEGF-A tended to be lower, while the ratio of VEGF-A165b to total VEGF-A tended to be higher in patients with MACCEs than in those without. The patients with a high ratio of VEGF-A165b to total VEGF-A had a significantly higher risk of MACCEs using the cut-off values for MACCEs at day 30 after PCI (0.87 vs. 0.25, log-rank test, p = 0.0058). Conclusion The assessment of VEGF-A165b combined with VEGF-A may be a valuable screening tool for predicting MACCEs in clinical practice.


Medicine | 2017

The combination assessment of lipid pool and thrombus by optical coherence tomography can predict the filter no-reflow in primary PCI for ST elevated myocardial infarction

Yosuke Negishi; Hideki Ishii; Susumu Suzuki; Toshijiro Aoki; Naoki Iwakawa; Hiroki Kojima; Kazuhiro Harada; Kenshi Hirayama; Takayuki Mitsuda; Takuya Sumi; Akihito Tanaka; Yasuhiro Ogawa; Katsuhiro Kawaguchi; Toyoaki Murohara

Abstract The usefulness of distal protection devices is still controversial. Moreover, there is no report on thrombus evaluation by using optical coherence tomography (OCT) for determining whether to use a distal protection device. The aim of the present study was to investigate the predictor of filter no-reflow (FNR) by using OCT in primary percutaneous coronary intervention (PCI) for ST-elevated acute myocardial infarction (STEMI). We performed preinterventional OCT in 25 patients with STEMI who were undergoing primary PCI with Filtrap. FNR was defined as coronary flow decreasing to TIMI flow grade 0 after mechanical dilatation. FNR was observed in 13 cases (52%). In the comparisons between cases with or without the FNR, the stent length, lipid pool length, lipid pool + thrombus length, and lipid pool + thrombus index showed significant differences. In multivariate analysis, lipid pool + thrombus length was the only independent predictor of FNR (OR 1.438, 95% CI 1.001 - 2.064, P < .05). The optimal cut-off value of lipid pool + thrombus length for predicting FNR was 13.1 mm (AUC = 0.840, sensitivity 76.9%, specificity 75.0%). Moreover, when adding the evaluation of thrombus length to that of lipid pool length, the prediction accuracy of FNR further increased (IDI 0.14: 0.019–0.25, P = .023). The longitudinal length of the lipid pool plus thrombus was an independent predictor of FNR and the prediction accuracy improved by adding the thrombus to the lipid pool. These results might be useful for making intraoperative judgment about whether filter devices should be applied in primary PCI for STEMI.


Journal of Cardiology | 2017

Impact of post-dilatation on longitudinal stent elongation: An in vitro study

Takuya Sumi; Hideki Ishii; Akihito Tanaka; Susumu Suzuki; Hiroki Kojima; Naoki Iwakawa; Toshijiro Aoki; Kenshi Hirayama; Takayuki Mitsuda; Kazuhiro Harada; Yosuke Negishi; Tomoyuki Ota; Kenji Kada; Toyoaki Murohara

OBJECTIVES To evaluate whether balloon inflation for post-dilatation causes longitudinal stent deformation (LSD). METHODS AND RESULTS Two stents, sized 2.5mm×28mm and 3.5mm×28mm (Nobori®, biodegradable polymer biolimus-eluting stent; Ultimaster®, biodegradable polymer sirolimus-eluting stent; Terumo Co., Tokyo, Japan), were deployed at nominal pressure in straight and tapered silicon vessel models. Then, post-dilatation was performed in two ways: dilatation from the distal (D-P group) or proximal (P-D group) side of the stent. Microscopic findings showed that the stents were elongated during every step of the procedure regardless of the post-dilatation method and type of vessel model. The D-P group showed linear elongation during each step of post-dilatation (straight model: 28.7±0.3mm vs. 29.9±0.3mm, p=0.002; tapered model: 28.0±0.1mm vs. 29.9±0.1mm, p<0.001). In contrast, in the P-D group, the most significant change was observed in the first step of post-dilatation and only slight changes were observed thereafter (straight model: 28.6±0.1mm vs. 29.5±0.1mm, p<0.001; tapered model: 28.2±0.1mm vs. 29.5±0.1mm, p<0.001). Optical frequency domain imaging analysis showed that the frequency of stent strut malapposition was positively correlated with the percentage change in stent length (r=0.74, p<0.0001). CONCLUSION LSD was observed during every step of post-dilatation in both the straight and tapered vessel models. However, some differences were observed between the D-P and P-D groups. Minimizing stent strut malapposition may reduce the risk of LSD.

Collaboration


Dive into the Kenshi Hirayama's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge