著者
Kenji Hanada Takahiko Kinjo Hiroaki Yokoyama Michiko Tsushima Maiko Senoo Hiroaki Ichikawa Fumie Nishizaki Shuji Shibutani Takashi Yokota Ken Okumura Hirofumi Tomita
出版者
The Japanese Circulation Society
雑誌
Circulation Journal (ISSN:13469843)
巻号頁・発行日
pp.CJ-23-0023, (Released:2023-09-28)
参考文献数
38
被引用文献数
2

Background: The characteristics and clinical outcomes associated with sustained ventricular tachycardia and fibrillation (VT/VF) in Japanese acute myocardial infarction (AMI) patients remain unknown.Methods and Results: Consecutive AMI patients (n=1,941) transferred to the Hirosaki University Hospital and treated with primary percutaneous coronary intervention (PCI) within 12 h of onset were retrospectively studied. The incidence of VT/VF during hospitalization was 8.3%, and 75% of cases occurred by the end of PCI. Independent predictors associated with VT/VF occurrence by the end of PCI and after PCI, respectively, were identified. Additionally, the differences between patients with VT and VF were examined, which revealed that the characteristics of patients and predictors for VT and VF were clearly different. Additionally, the QRS duration during VT was measured, which demonstrated the possible involvement of Purkinje fibers for VT in the acute phase of AMI. Of the patients with VT/VF, 12% required ECMO support due to refractory VT/VF despite intravenous antiarrhythmic agents such as β-blockers, amiodarone, and nifekalant. Among the patients discharged alive, 1,690 were followed up for a mean of 3.7 years. VT/VF occurrence during hospitalization did not affect the mid-term clinical outcomes even in patients with VT.Conclusions: The results clearly indicated that VT/VF is still a serious complications of AMI. We need to identify patients at high risk of developing VT/VF for careful observation and appropriate intervention.
著者
Ken Okumura Hirofumi Tomita Michikazu Nakai Eitaro Kodani Masaharu Akao Shinya Suzuki Kenshi Hayashi Mitsuaki Sawano Masahiko Goya Takeshi Yamashita Keiichi Fukuda Hisashi Ogawa Toyonobu Tsuda Mitsuaki Isobe Kazunori Toyoda Yoshihiro Miyamoto Hiroaki Miyata Tomonori Okamura Yusuke Sasahara for the J-RISK AF Research Group
出版者
The Japanese Circulation Society
雑誌
Circulation Journal (ISSN:13469843)
巻号頁・発行日
pp.CJ-20-1075, (Released:2021-03-25)
参考文献数
22
被引用文献数
1 15

Background:Recently, identification of independent risk factors for ischemic stroke in Japanese non-valvular atrial fibrillation (NVAF) patients was made by analyzing the 5 major Japanese registries: J-RHYTHM Registry, Fushimi AF Registry, Shinken Database, Keio interhospital Cardiovascular Studies, and the Hokuriku-Plus AF Registry.Methods and Results:The predictive value of the risk scheme in Japanese NVAF patients was assessed. Of 16,918 patients, 12,289 NVAF patients were analyzed (mean follow up, 649±181 days). Hazard ratios (HRs) of each significant, independent risk factor were determined by using adjusted Cox-hazard proportional analysis. Scoring system for ischemic stroke was created by transforming HR logarithmically and was estimated by c-statistic. During the 21,820 person-years follow up, 241 ischemic stroke events occurred. Significant risk factors were: being elderly (aged 75–84 years [E], HR=1.74), extreme elderly (≥85 years [EE], HR=2.41), having hypertension (H, HR=1.60), previous stroke (S, HR=2.75), type of AF (persistent/permanent) (T, HR=1.59), and low body mass index <18.5 kg/m2(L, HR=1.55) after adjusting for oral anticoagulant treatment. The score was assigned as follows: 1 point to H, E, L, and T, and 2 points to EE and S (HELT-E2S2score). The C-statistic, using this score, was 0.681 (95% confidence interval [CI]=0.647–0.714), which was significantly higher than those using CHADS2(0.647; 95% CI=0.614–0.681, P=0.027 for comparison) and CHA2DS2-VASc scores (0.641; 95% CI=0.608–0.673, P=0.008).Conclusions:The HELT-E2S2score may be useful for identifying Japanese NVAF patients at risk of ischemic stroke.
著者
Hirofumi Tomita Ken Okumura Hiroshi Inoue Hirotsugu Atarashi Takeshi Yamashita Hideki Origasa Eiki Tsushima on behalf of the J-RHYTHM Registry Investigators
出版者
日本循環器学会
雑誌
Circulation Journal (ISSN:13469843)
巻号頁・発行日
pp.CJ-15-0095, (Released:2015-05-13)
参考文献数
35
被引用文献数
9 42

Background:Because the current Japanese guideline recommends CHADS2score-based risk stratification in nonvalvular atrial fibrillation (NVAF) patients and does not list female sex as a risk for thromboembolic events, we designed the present study to compare the CHA2DS2-VASc and CHA2DS2-VA scores in the J-RHYTHM Registry.Methods and Results:We prospectively assessed the incidence of thromboembolic events for 2 years in 997 NVAF patients without warfarin treatment (age 68±12 years, 294 females). The predictive value of the CHA2DS2-VASc and CHA2DS2-VA scores for thromboembolic events was evaluated by c-statistic difference and net reclassification improvement (NRI). Thromboembolic events occurred in 7/294 females (1.2%/year) and 23/703 males (1.6%/year) (odds ratio 0.72 for female to male, 95% confidence interval (CI) 0.28–1.62, P=0.44). No sex difference was found in patient groups stratified by CHA2DS2-VASc and CHA2DS2-VA scores. There were significant c-statistic difference (0.029, Z=2.3, P=0.02) and NRI (0.11, 95% CI 0.01–0.20, P=0.02), with the CHA2DS2-VA score being superior to the CHA2DS2-VASc score. In patients with CHA2DS2-VASc scores 0 and 1 (n=374), there were markedly significant c-statistic difference (0.053, Z=6.6, P<0.0001) and NRI (0.11, 95% CI 0.07–0.14, P<0.0001), again supporting superiority of CHA2DS2-VA to CHA2DS2-VASc score.Conclusions:In Japanese NVAF patients, the CHA2DS2-VA score, a risk scoring system excluding female sex from CHA2DS2-VASc, may be more useful in risk stratification for thromboembolic events than CHA2DS2-VASc score, especially in identifying truly low-risk patients.
著者
Ken Okumura Hiroshi Inoue Hirotsugu Atarashi Takeshi Yamashita Hirofumi Tomita Hideki Origasa for the J-RHYTHM Registry Investigators.
出版者
日本循環器学会
雑誌
Circulation Journal (ISSN:13469843)
巻号頁・発行日
vol.78, no.7, pp.1593-1599, 2014 (Released:2014-06-25)
参考文献数
21
被引用文献数
32 81

Background: Recent European guidelines recommended the CHA2DS2-VASc score for thromboembolic and the HAS-BLED score for bleeding risk stratifications. We validated these scores in 7,384 Japanese patients with nonvalvular atrial fibrillation (NVAF) enrolled in the J-RHYTHM Registry. Methods and Results: Of the study cohort, 6,387 patients taking warfarin and the other 997 not taking warfarin were prospectively examined for 2 years. Thromboembolic and major bleeding risks were stratified by modified CHA2DS2-VASc (mCHA2DS2-VASc) and HAS-BLED (mHAS-BLED) scores, respectively. Of the patients with mCHA2DS2-VASc score 0, 1, and ≥2, thromboembolism occurred in 2/141 (0.7%/year), 4/233 (0.9%/year), and 24/623 (1.9%/year), respectively, in the non-warfarin group, and in 1/346 (0.1%/year, P=0.19 vs. non-warfarin), 4/912 (0.2%/year, P=0.05), and 92/5,129 (0.9%/year, P=0.0005), respectively, in the warfarin group. When female sex was excluded from the score, thromboembolism occurred in 2/180 patients (0.6%/year), 5/245 (1.0%/year), and 23/572 (1.6%/year), respectively, in the non-warfarin group, and in 1/422 (0.1%/year, P=0.20 vs. non-warfarin), 5/1,096 (0.2%/year, P=0.02), and 91/4,869 (0.9%/year, P=0.0005), respectively, in the warfarin group. Patients with mHAS-BLED scores ≥3 were at high risk for major bleeding irrespective of warfarin treatment (1.3 and 2.6%/year in the non-warfarin and warfarin groups, respectively). Conclusions: In Japanese NVAF patients, the mCHA2DS2-VASc score is useful for identifying patients at truly low risk of thromboembolism. Female sex may be excluded as a risk from the score. mHAS-BLED score ≥3 is useful for identifying patients at high risk of major bleeding.  (Circ J 2014; 78: 1593–1599)
著者
Tsuyoshi Yamaura Yoshiyuki Kajikawa Hirofumi Tomita Masaki Satoh
出版者
(公社)日本気象学会
雑誌
SOLA (ISSN:13496476)
巻号頁・発行日
vol.9, pp.89-93, 2013 (Released:2013-07-17)
参考文献数
21
被引用文献数
3 5

The impact of a tropical cyclone on the northward migration of the Baiu frontal zone (BFZ) is investigated in the case of the tropical cyclone MAWAR (2012) using a global cloud-system resolving model, called NICAM. From 4 to 6 June in 2012, the BFZ rapidly shifts northward with MAWAR. A simulation with the initial data of 29 May reproduces the northward migration of the BFZ and the tropical cyclone. Strong southerlies on the eastern side of the tropical cyclone transport moist and high-temperature air into the BFZ. This horizontal advection affects the northward migration of the BFZ. In contrast, the BFZ stagnates to the south of Japan in another simulation with the initial data of 30 May because the tropical cyclone track is diverted eastward. Thus, realistic reproducibility of a tropical cyclone is needed for better simulations and prediction of the BFZ migration.
著者
Ken Okumura Hirofumi Tomita Michikazu Nakai Eitaro Kodani Masaharu Akao Shinya Suzuki Kenshi Hayashi Mitsuaki Sawano Masahiko Goya Takeshi Yamashita Keiichi Fukuda Hisashi Ogawa Toyonobu Tsuda Mitsuaki Isobe Kazunori Toyoda Yoshihiro Miyamoto Hiroaki Miyata Tomonori Okamura Yusuke Sasahara for the J-RISK AF Research Group
出版者
The Japanese Circulation Society
雑誌
Circulation Journal (ISSN:13469843)
巻号頁・発行日
vol.85, no.8, pp.1254-1262, 2021-07-21 (Released:2021-07-21)
参考文献数
22
被引用文献数
1 15

Background:Recently, identification of independent risk factors for ischemic stroke in Japanese non-valvular atrial fibrillation (NVAF) patients was made by analyzing the 5 major Japanese registries: J-RHYTHM Registry, Fushimi AF Registry, Shinken Database, Keio interhospital Cardiovascular Studies, and the Hokuriku-Plus AF Registry.Methods and Results:The predictive value of the risk scheme in Japanese NVAF patients was assessed. Of 16,918 patients, 12,289 NVAF patients were analyzed (mean follow up, 649±181 days). Hazard ratios (HRs) of each significant, independent risk factor were determined by using adjusted Cox-hazard proportional analysis. Scoring system for ischemic stroke was created by transforming HR logarithmically and was estimated by c-statistic. During the 21,820 person-years follow up, 241 ischemic stroke events occurred. Significant risk factors were: being elderly (aged 75–84 years [E], HR=1.74), extreme elderly (≥85 years [EE], HR=2.41), having hypertension (H, HR=1.60), previous stroke (S, HR=2.75), type of AF (persistent/permanent) (T, HR=1.59), and low body mass index <18.5 kg/m2(L, HR=1.55) after adjusting for oral anticoagulant treatment. The score was assigned as follows: 1 point to H, E, L, and T, and 2 points to EE and S (HELT-E2S2score). The C-statistic, using this score, was 0.681 (95% confidence interval [CI]=0.647–0.714), which was significantly higher than those using CHADS2(0.647; 95% CI=0.614–0.681, P=0.027 for comparison) and CHA2DS2-VASc scores (0.641; 95% CI=0.608–0.673, P=0.008).Conclusions:The HELT-E2S2score may be useful for identifying Japanese NVAF patients at risk of ischemic stroke.
著者
Hiroaki Yokoyama Hirofumi Tomita Satoshi Honda Kensaku Nishihira Sunao Kojima Misa Takegami Yasuhide Asaumi Jun Yamashita Mike Saji Masami Kosuge Jun Takahashi Yasuhiko Sakata Morimasa Takayama Tetsuya Sumiyoshi Hisao Ogawa Kazuo Kimura Satoshi Yasuda on behalf of the JAMIR Investigators
出版者
The Japanese Circulation Society
雑誌
Circulation Journal (ISSN:13469843)
巻号頁・発行日
pp.CJ-21-0705, (Released:2021-11-20)
参考文献数
33
被引用文献数
6

Background:Acute myocardial infarction (AMI) patients with low body mass index (BMI) exhibit worse clinical outcomes than obese patients; however, to our knowledge, no prospective, nationwide study has assessed the effect of BMI on the clinical outcomes of AMI patients.Methods and Results:In this multi-center, prospective, nationwide Japanese trial, 2,373 AMI patients who underwent emergent percutaneous coronary intervention within 12 h of onset from the Japanese AMI Registry (JAMIR) were identified. Patients were divided into the following 4 groups based on their BMI at admission: Q1 group (BMI <18.5 kg/m2, n=133), Q2 group (18.5≤BMI<25.0 kg/m2, n=1,424), Q3 group (25.0≤BMI<30.0 kg/m2, n=672), and Q4 group (30.0 kg/m2≤BMI, n=144). The primary endpoint was all-cause death, and the secondary endpoint was a composite of cardiovascular death, non-fatal myocardial infarction (MI), and non-fatal stroke. The median follow-up period was 358 days. Q1 patients were older and had lower prevalence of coronary risk factors. Q1 patients also had higher all-cause mortality and higher incidence of secondary endpoints than normal-weight or obese AMI patients. Multivariate analysis showed that low BMI (Q1 group) was an independent predictor for primary endpoint.Conclusions:AMI patients with low BMI had fewer coronary risk factors but worse clinical outcomes than normal-weight or obese patients.
著者
Masato Narita Masahiro Yamada Michiko Tsushima Natsumi Kudo Tomo Kato Yoshikazu Yokono Yuichi Toyama Maiko Senoo Manabu Yonekura Noritomo Narita Yoshihiro Kimura Kaori Sawada Itoyo Tokuda Hirofumi Tomita
出版者
International Heart Journal Association
雑誌
International Heart Journal (ISSN:13492365)
巻号頁・発行日
pp.18-511, (Released:2019-04-25)
参考文献数
37
被引用文献数
11

Although there are several diagnostic criteria for left ventricular hypertrophy (LVH), their sensitivity remains low. A recent study reported that the sum of the amplitude of the deepest S wave in any lead (SD) and the S wave in lead V4 (SV4) (SD + SV4) improved sensitivity compared with commonly used criteria. To test whether this new formula improves sensitivity in the Japanese general population, we analyzed 12-lead electrocardiograms for Japanese residents participating in the Iwaki Health Promotion Project (n = 866). Left ventricular mass was calculated by echocardiography, indicating that 156 (18%) of the study population had LVH. In receiver operating characteristic analyses, the sum of the R wave in limb lead Ι (RLΙ) and the S wave in V4 (SV4) (RLΙ + SV4) showed a higher area under the curve (AUC = 0.76) than the Sokolow-Lyon voltage criteria (0.61) and the SD + SV4 criteria (0.63), and almost the same AUC as the Cornell voltage criteria (0.74) and the Cornell product criteria (0.76). The validation study also showed similar results. The cutoff values of RLΙ + SV4 criteria were ≥1.6 mV in men and ≥1.4 mV in women with a sensitivity of 39% and a specificity of 89%, whereas the sensitivity and specificity calculated based on SD + SV4 criteria were 21% and 94%, respectively. Thus, the diagnostic criterion of RLΙ + SV4 seems to be more useful than the previous criteria for diagnosing LVH in the Japanese general population.
著者
Kazuomi Kario Eiichiro Yamamoto Hirofumi Tomita Takafumi Okura Shigeru Saito Takafumi Ueno Daiki Yasuhara Kazuyuki Shimada on behalf of the SYMPLICITY HTN-Japan Investigators
出版者
The Japanese Circulation Society
雑誌
Circulation Journal (ISSN:13469843)
巻号頁・発行日
pp.CJ-18-1018, (Released:2019-02-13)
参考文献数
32
被引用文献数
27

Background: SYMPLICITY HTN-Japan is a prospective, randomized, controlled trial comparing renal denervation (RDN) with standard pharmacologic therapy for treatment of uncontrolled hypertension (HTN). Methods and Results: Patients enrolled had uncontrolled HTN, defined as office systolic blood pressure (SBP) ≥160 mmHg and 24-h ambulatory SBP ≥135 mmHg, on ≥3 antihypertensive drugs of maximally tolerated dose for at least 6 weeks prior to enrollment. Randomization was 1:1 to RDN or maintenance of current medical therapy (control). Patients were followed every 6 months post-randomization for up to 36 months. There were 22 patients randomized to RDN and 19 to control, and 11 patients were crossed over and received RDN at 6 months post-randomization. For the RDN group (n=22), office SBP reduction was −32.8±20.1 mmHg and office DBP reduction was −15.8±12.6 mmHg at 36 months post-procedure, both P<0.001. For the combined RDN and crossover group (n=33), office SBP reduction was −26.7±18.9 mmHg and office DBP reduction was −12.7±11.8 mmHg at 30 months post-procedure, both P<0.001. There were no procedural-, device- or treatment-related safety events through 36 months. Conclusions: SYMPLICTY HTN-Japan is the first randomized controlled trial to evaluate RDN in an Asian population. Despite the small number of enrollments, results show patients who received RDN therapy maintained SBP reduction out to 36 months.
著者
Ryuji YOSHIDA Yoshiaki MIYAMOTO Hirofumi TOMITA Yoshiyuki KAJIKAWA
出版者
(公社)日本気象学会
雑誌
気象集誌. 第2輯 (ISSN:00261165)
巻号頁・発行日
vol.95, no.1, pp.35-47, 2017 (Released:2017-03-01)
参考文献数
29
被引用文献数
11

The environmental conditions for tropical cyclone genesis are examined by numerical experiment. We focus on the case of a non-developing disturbance showed features for tropical cyclone genesis in the Pacific Area Long-term Atmospheric observation for Understanding climate change in 2010 (PALAU2010) observation campaign over the western North Pacific. We clarify the importance of the presence of abundant moisture around the disturbance for continuous convection and demonstrate that the collocation of a mid-level vortex and a low-level vortex, i.e., the persistence of an upright structure of vortices, is important in tropical cyclone genesis. We conduct two numerical experiments using the Weather Research and Forecasting Model Advanced Research WRF model in double nested domains with a horizontal grid space of 27 km and 9 km for the outer domain and the inner domain, respectively. The first experiment is based on reanalysis data (a control experiment) and the second includes increased water vapor content over the northwestern dry area of the disturbance. In the control experiment, the disturbance did not develop into a tropical cyclone in spite of the existence of the mid-level and low-level vortices. In contrast, the sensitivity experiment shows that a tropical cyclone was formed from the disturbance with increased water vapor content. The presence of persistent upright vortices was supported by continuous convection until the genesis of the tropical cyclone.