Juntaro Deyama
University of Yamanashi
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Publication
Featured researches published by Juntaro Deyama.
Atherosclerosis | 2011
Mitsumasa Hirano; Takamitsu Nakamura; Yoshinobu Kitta; Isao Takishima; Juntaro Deyama; Tsuyoshi Kobayashi; Daisuke Fujioka; Yukio Saito; Kazuhiro Watanabe; Yosuke Watanabe; Ken-ichi Kawabata; Jyun-ei Obata; Kiyotaka Kugiyama
OBJECTIVE This study examined whether changes in maximum intima-media thickness of carotid plaque (plaque-IMTmax) over 6 months predict future coronary events in patients with carotid plaque and coronary artery disease (CAD). METHODS This study included 240 patients with CAD who had a carotid plaque (IMT ≥ 1.1mm) at entry. A carotid ultrasound examination was performed at entry (1st test) and after 6 months (2nd test). The carotid plaque with the greatest axial thickness at the 1st test was selected as the target plaque for monitoring the change in plaque-IMTmax. After the 2nd test, patients were prospectively followed-up for 3 years or until the occurrence of one of the following coronary events: cardiac death, non-fatal myocardial infarction, or unstable angina pectoris requiring coronary revascularization. RESULTS The change in plaque-IMTmax over 6 months ranged from -0.85 to 0.97 mm (mean, -0.006 ± 0.319 mm). There were 41 events during follow-up. In a stepwise multivariate Cox proportional hazards model, the change in plaque-IMTmax was a significant predictor of coronary events after adjustment for known risk factors (HR per 0.1mm increase over 6 months, 1.21; 95%CI, 1.10-1.33, p=0.0001). Analysis of receiver operating characteristic (ROC) curves showed that the addition of the change in plaque-IMTmax to conventional risk factors resulted in a greater area under the ROC curve compared with conventional risk factors alone (0.81 and 0.70, respectively, p=0.02). CONCLUSION Short-term progression of carotid plaque-IMTmax was associated with future coronary events in patients with CAD.
International Journal of Cardiology | 2015
Jun Nakamura; Takamitsu Nakamura; Juntaro Deyama; Daisuke Fujioka; Ken-ichi Kawabata; Jun-ei Obata; Kazuhiro Watanabe; Yosuke Watanabe; Kiyotaka Kugiyama
BACKGROUND Contrast-enhanced ultrasound (CEUS) of the carotid artery is a potential technique for imaging plaque neovascularization, a feature of unstable atherosclerotic plaques. This study examined whether assessment of intra-plaque neovascularization of the carotid artery using CEUS provides prognostic information in patients with coronary artery disease (CAD). METHODS A total of 206 patients with stable CAD underwent a CEUS examination of the carotid artery and were followed up prospectively for <38 months or until a cardiac event (cardiac death, non-fatal myocardial infarction (MI), unstable angina pectoris (uAP) requiring unplanned coronary revascularization, or heart failure requiring hospitalization). The degree of contrast signals measured within the carotid plaque was quantified by calculating the mean gray scale level within the region of interest of the carotid plaque, expressed as plaque enhanced intensity. RESULTS During the follow-up period, 31 events occurred (2 cardiac deaths, 7 non-fatal MIs, 16 uAP, and 6 heart failure). Multivariate Cox proportional hazard analysis showed that plaque enhanced intensity was a significant predictor of cardiac events independent of traditional risk factors (HR, 1.13; 95% CI, 1.05-1.21; p<0.001). The addition of the plaque enhanced intensity to traditional risk factors resulted in net reclassification improvement (NRI) and integrated discrimination improvement (IDI) (NRI 0.62, p=0.001; and IDI 0.106, p=0.002). CONCLUSIONS The assessment of carotid plaque neovascularization using quantitative analysis of CEUS may be useful for risk stratification in patients with CAD.
International Journal of Cardiology | 2018
Juntaro Deyama; Takamitsu Nakamura; Yukio Saito; Jun-ei Obata; Daisuke Fujioka; Kazuto Nakamura; Kazuhiro Watanabe; Kiyotaka Kugiyama
BACKGROUND The prevalence of coronary artery spasm (CAS) inducible by intracoronary injection of acetylcholine (ACh) is high in survivors of acute myocardial infarction (AMI). Although there is a potential risk of sudden cardiac death in patients with CAS, the prognostic value of CAS was not clear. Thus, this study examined the effect of CAS on long-term prognosis in survivors of AMI in a prospective manner. METHODS The study included a total of 437 patients with AMI who underwent a CAS provocation test using ACh. All patients were followed prospectively for 5years or until the occurrence of the primary composite endpoint that consisted of cardiac death and acute coronary syndrome (ACS). RESULTS CAS was induced in 195 (45%) of the study patients. During the follow-up period, 30 patients had a recurrent event (4 had cardiac death and 26 had ACS). Kaplan-Meier estimates in time-to-first-event analysis demonstrated a similar probability of the primary endpoint in patients with and without inducible CAS (p=0.13, log-rank test). The rate of each component of the composite endpoint was also comparable between the 2 patient groups. In Cox proportional hazards risk analysis, treatment with calcium channel blockers (CCBs) negatively predicted the primary endpoints in patients with inducible CAS (HR, 0.21; 95% CI, 0.08-0.55, p<0.01). CONCLUSIONS The presence of inducible CAS did not increase the incidence of the cardiac events in AMI survivors. Treatment with CCBs may improve outcomes in AMI survivors with inducible CAS. CLINICAL TRIAL REGISTRATION URL: https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000021340, unique identifier: UMIN000018432.
Circulation | 2013
Juntaro Deyama; Takamitsu Nakamura; Isao Takishima; Daisuke Fujioka; Ken-ichi Kawabata; Jun-ei Obata; Kazuhiro Watanabe; Yosuke Watanabe; Yukio Saito; Hideto Mishina; Kiyotaka Kugiyama
Cardiovascular endocrinology | 2017
Satoshi Oka; Juntaro Deyama; Ken Umetani; Tomoko Harama; Takuya Shimizu; Aritaka Makino; Keita Sano; Masahiko Nakamura
Circulation | 2014
Jun Nakamura; Takamitsu Nakamura; Juntaro Deyama; Daisuke Fujioka; Ken-ichi Kawabata; Jun-ei Obata; Kazuhiro Watanabe; Yosuke Watanabe; Kiyotaka Kugiyama
Shinzo | 2013
Juntaro Deyama; Yuta Ichinose; Yoshinobu Kitta; Keita Sano; Ken-ichi Kawabata; Jun-ei Obata; Masahiko Matsumoto; Kiyotaka Kugiyama
Circulation | 2013
Juntaro Deyama; Takamitsu Nakamura; Jun Nakamura; Isao Takishima; Mika Futamata; Tetsuji Mochida; Manabu Uematsu; Wataru Sugamata; Daisuke Fujioka; Yukio Saito; Kazuto Nakamura; Yoshinobu Kitta; Ken-ichi Kawabata; Jun-ei Obata; Kiyotaka Kugiyama
Circulation | 2012
Yoshinobu Kitta; Takamitsu Nakamura; Manabu Uematsu; Wataru Sugamata; Juntaro Deyama; Daisuke Fujioka; Yukio Saito; Ken-ichi Kawabata; Jun-ei Obata; Kiyotaka Kugiyama
Circulation | 2012
Yoshinobu Kitta; Takamitsu Nakamura; Manabu Uematsu; Wataru Sugamata; Juntaro Deyama; Daisuke Fujioka; Yukio Saito; Ken-ichi Kawabata; Jun-ei Obata; Kiyotaka Kugiyama