Network


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

Hotspot


Dive into the research topics where Kiyotaka Ohshima is active.

Publication


Featured researches published by Kiyotaka Ohshima.


European Journal of Heart Failure | 2005

Serum markers of angiogenesis and myocardial ultrasonic tissue characterization in patients with dilated cardiomyopathy

Tomoaki Ohtsuka; Katsuji Inoue; Yuji Hara; Norikatsu Morioka; Kiyotaka Ohshima; Jun Suzuki; Akiyoshi Ogimoto; Jitsuo Higaki

It has been proven that a disturbance in angiogenesis contributes to the progression of myocardial interstitial fibrosis in idiopathic dilated cardiomyopathy (DCM). This study was designed to evaluate the relationship between serum activity of angiogenic factors and myocardial ultrasonic tissue characterization in patients with DCM.


Journal of Cardiology | 2009

Relationship between plaque composition and no-reflow phenomenon following primary angioplasty in patients with ST-segment elevation myocardial infarction--analysis with virtual histology intravascular ultrasound.

Kousei Ohshima; Shuntaro Ikeda; Kouki Watanabe; Kenichi Yamane; Naoki Izumi; Ken Ishibashi; Kiyotaka Ohshima; Mareomi Hamada

BACKGROUND The angiographic no-reflow phenomenon after primary percutaneous coronary intervention (PCI) carries a poor prognosis in patients with ST-segment elevation myocardial infarction (STEMI). However, the type of plaque composition that associates with the angiographic no-reflow phenomenon remains unclear. METHODS A total of 44 patients with STEMI were enrolled in this study. After thrombectomy with an aspiration catheter, virtual histology intravascular ultrasound (VH-IVUS) of the infarct-related vessel was performed. Patients were divided into two groups according to final thrombolysis in myocardial infarction (TIMI) flow grade at the completion of PCI procedure. Complete reperfusion group (CR-group) was defined as final TIMI flow grade 3, and no-reflow group (NR-group) was defined as final TIMI flow < or = 2. The relationship between plaque composition and angiographic no-reflow phenomenon was analyzed. RESULTS The angiographic no-reflow phenomenon was observed in 20 individuals. The summation of the percentage of fibrofatty+necrotic core and fibrofatty+dense calcium was significantly higher in the NR-group. Receiver-operating characteristics analysis revealed that the summation of the volume and percentage of fibrofatty+necrotic core (> 20.1 mm(3), 26.2%) and fibrofatty+dense calcium (> 20.0 mm(3), 22.6%) predict the angiographic no-flow phenomenon. CONCLUSION The fibrofatty-rich component with necrotic core or dense calcium derived from VH-IVUS is closely related to the angiographic no-reflow phenomenon observed in primary PCI.


Journal of Cardiology | 2011

Cavity volume of ruptured plaque is an independent predictor for angiographic no-reflow phenomenon during primary angioplasty in patients with ST-segment elevation myocardial infarction

Kousei Ohshima; Shuntaro Ikeda; Hisaki Kadota; Kenichi Yamane; Naoki Izumi; Hiroshi Kawazoe; Kiyotaka Ohshima; Mareomi Hamada

BACKGROUND Plaque rupture plays a critical role for the development of acute myocardial infarction. However, whether quantitative parameters with regard to the cavity size of ruptured plaque are associated with no-reflow (NR) phenomenon following primary angioplasty remains to be elucidated. METHODS AND RESULTS A total of 53 patients with de novo ST-elevation myocardial infarction (STEMI) who had plaque rupture at the culprit lesion defined by pre-intervention virtual histology intravascular ultrasound (VH-IVUS) were enrolled. Patients were divided into two groups according to the presence of NR phenomenon: NR group (n=19) and non-NR group (n = 34). By VH-IVUS, we evaluated cavity length, maximum area, and volume of ruptured plaque in culprit lesions. The cavity length, maximum area, and volume were significantly higher in the NR group than those of the non-NR group (4.8 ± 2.1 mm vs. 2.9 ± 4.8 mm, p < 0.001; 3.6 ± 1.4 mm² vs. 1.9 ± 0.5 mm², p < 0.001; 11.5 ± 6.3 mm³ vs. 3.7 ± 2.2 cm³, p < 0.001). A multiple logistic regression analysis revealed that the cavity volume was an independent risk for NR phenomenon. Receiver-operating characteristic analysis revealed that the cavity volume could predict NR phenomenon. CONCLUSIONS The cavity size of ruptured plaque is closely associated with NR phenomenon in patients with STEMI. Evaluation of the cavity volume by VH-IVUS may provide useful information for the prediction of NR phenomenon.


Journal of Cardiology | 2016

Impact of chronic use of cibenzoline on left ventricular pressure gradient and left ventricular remodeling in patients with hypertrophic obstructive cardiomyopathy.

Mareomi Hamada; Shuntaro Ikeda; Kiyotaka Ohshima; Masayuki Nakamura; Norio Kubota; Akiyoshi Ogimoto

BACKGROUND Cibenzoline, a class Ia antiarrhythmic drug, is useful for reducing the left ventricular pressure gradient (LVPG) in patients with hypertrophic obstructive cardiomyopathy (HOCM). However, chronic effects of cibenzoline on LVPG and left ventricular (LV) remodeling are unknown. METHODS Forty-one patients with HOCM participated in this study. Echocardiographic, electrocardiographic, and brain natriuretic peptide (BNP) data collected before and after cibenzoline treatment were compared. From the relation between LVPG and plasma concentration of cibenzoline, an efficacious plasma concentration of cibenzoline was estimated. RESULTS The mean follow-up period was 74.2±47.1 months. The LVPG decreased from 104.8±62.6mmHg to 27.6±30.5mmHg (p<0.0001). The LV end-diastolic dimension increased from 42.8±5.8mm to 46.2±5.4mm (p<0.0001), but neither LV end-systolic dimension nor LV fractional shortening changed significantly. The left atrial dimension decreased from 40.0±4.7mm to 36.2±5.1mm (p<0.0001). The E-wave velocity/A-wave velocity ratio increased, early diastolic annular velocity (Ea) increased, and E/Ea ratio decreased. The interventricular septal wall thickness, LV posterior wall thickness, the Sokolow-Lyon index, and the depth of negative T wave decreased. The heart rate-corrected QT interval was shortened. Plasma BNP level decreased from 418.8±423.7pg/ml to 213.7±154.1pg/ml (p<0.02). The safe and efficacious plasma concentration of cibenzoline was between 300ng/mL and 1500ng/mL. CONCLUSIONS Long-term treatment with cibenzoline attenuated LVPG, improved LV diastolic dysfunction, and induced LV hypertrophy regression in patients with HOCM without causing serious complications.


International Journal of Cardiology | 2013

Impact of culprit plaque volume and composition on myocardial microcirculation following primary angioplasty in patients with ST-segment elevation myocardial infarction: Virtual histology intravascular ultrasound analysis

Kousei Ohshima; Shuntaro Ikeda; Hisaki Kadota; Kenichi Yamane; Naoki Izumi; Kiyotaka Ohshima; Mareomi Hamada

BACKGROUND An impaired myocardial perfusion state after primary angioplasty is a strong predictor of long-term adverse outcomes in patients with STEMI. We assessed the relationship between culprit plaque characteristics and myocardial perfusion state after primary angioplasty in patients with ST-segment elevation myocardial infarction (STEMI). METHODS A total of 101 consecutive patients with de novo STEMI were divided into 3 groups according to the state of myocardial perfusion assessed by ST-segment elevation resolution (STR): Group A (complete: STR ≥ 70%, n=26), Group B (partial: STR<70% but ≥ 30%, n=55) and Group C (none: STR<30%, n=20). We analyzed plaque features by virtual histology intravascular ultrasound (VH-IVUS) and assessed the relationship between culprit plaque characteristics and STR after primary angioplasty. RESULTS Total plaque volume was significantly higher in Group C than in Groups A and B (146.4 ± 38.0 mm(3)vs. 93.3 ± 29.1 mm(3) and 105.8 ± 31.5 mm(3), p<0.001, respectively). Necrotic core (NC) volume was also significantly higher in Group C than in Groups A and B (25.4 ± 8.0m m(3), vs. 11.9 ± 6.3 mm(3) and 17.3 ± 9.7 mm(3), p<0.001, respectively). Analysis of receiver-operating characteristic curves revealed that total plaque volume and NC volume had the best diagnostic accuracy of all the VH-IVUS parameters to predict STR<30%. The optimal cutoff values (sensitivity/specificity) were 123.4 mm(3) (75.0%/75.3%) for total plaque volume and 20.3mm(3) (75.0%/74.1%) for NC volume. CONCLUSIONS Culprit plaque with large plaque burden and high NC volume is closely associated with poor STR after revascularization.


Esc Heart Failure | 2017

Impact of chronic kidney disease on the diuretic response of tolvaptan in acute decompensated heart failure

Shuntaro Ikeda; Kiyotaka Ohshima; Shigehiro Miyazaki; Hisaki Kadota; Hideaki Shimizu; Akiyoshi Ogimoto; Mareomi Hamada

This study investigated the relationship between the initial diuretic response to tolvaptan and clinical predictors for tolvaptan responders in patients with acute decompensated heart failure (ADHF).


Internal Medicine | 2015

A Patient with Dengue Fever Presenting with Rhabdomyolysis.

Masayuki Nakamura; Shuntaro Ikeda; Hiroyuki Nagahara; Tatsurou Hitsumoto; Shogo Matsui; Hisaki Kadota; Hideaki Shimizu; Kiyotaka Ohshima; Naoki Yakushiji; Mareomi Hamada

A 16-year-old boy stayed in Tokyo near Yoyogi Park for extracurricular high school activities. After returning home, he experienced an episode of fever and visited our emergency outpatient unit. He initially exhibited symptoms of leukopenia, thrombocytopenia and concomitant rhabdomyolysis and after admission simultaneously developed a biphasic fever and systemic erythema. Based on the results of reverse transcription polymerase chain reaction testing, he was finally diagnosed with dengue fever. After an absence of 70 years, dengue fever has reemerged as a domestic infection. Awareness of this trend led to our diagnosis.


Internal Medicine | 2018

Extracardiac Tumor From Duodenal Primary Gastrointestinal Stromal Tumor

Shigehiro Miyazaki; Akiyoshi Ogimoto; Shoichi Matsukage; Kiyotaka Ohshima

A 74-year-old woman with a duodenal primary gastrointestinal stromal tumor (GIST) presented to the emergency department with cardiogenic shock and died of cardiac tamponade due to extracardiac tumor rupture. A previous coronary computed tomography angiogram (Picture A) showed that the tumor had nutrient vessels from the right coronary artery and left anterior descending artery. Cardiovascular magnetic resonance imaging (Picture B) revealed that the tumor (arrow) had a heterogeneous contrast effect, and it continued from the cardiac muscle. She elected to receive conservative medical treatment. During the autopsy, an elastic, soft tumor measuring 7×8×7 cm was detected under the


Heart and Vessels | 2018

Coronary artery–left ventricular shunt: an important cause of chest pain in patients with hypertrophic cardiomyopathy

Mareomi Hamada; Akiyoshi Ogimoto; Kiyotaka Ohshima; Shigehiro Miyazaki; Norio Kubota; Shuntarto Ikeda

The influence of shunts between the coronary artery (CA) and the left ventricle (LV), on chest pain (CP) in patients with hypertrophic cardiomyopathy (HCM) is unknown. We examined the incidence of CA–LV shunts and their influence on CP in HCM patients. Twenty normal control subjects (NCS), 3 with CP due to CA–LV shunts (CP patients), and 60 with HCM participated. Interventricular septal wall thickness (IVST), LV posterior wall thickness (LVPWT), cardiac and stroke indexes (CI and SI), LV end-diastolic pressure (LVEDP), and proximal diameters of the CA were measured. Twenty-five HCM patients had a CA–LV shunt (41.7%). Both IVST and LVPWT were greater in the HCM patients than in NCS and CP patients. These values showed no significant differences between the HCM with shunt and HCM without shunt groups. CI and SI were lower in the HCM patients than in NCS and CP patients. LVEDP was higher in the HCM and CP patients than in NCS. CA diameters were larger in the HCM and CP patients than in NCS. CP was found in 32 HCM patients (53%). The incidence of CP was greater in the HCM with shunt group than in HCM without shunt group (80 vs. 34%, p < 0.0005). There was no significant difference in CA diameters between the HCM patients with CP and those without CP. CA–LV shunts are often found in HCM patients and are closely related to CP. Thus, CA–LV shunts are an important factor behind CP in HCM patients.


Journal of Cardiology Cases | 2016

Successful treatment of cerebral emboli with tissue plasminogen activator in a patient with takotsubo cardiomyopathy: A case report

Shuntaro Ikeda; Chika Murakami; Shigehiro Miyazaki; Tatsuro Hitsumoto; Hisaki Kadota; Hideaki Shimizu; Kiyotaka Ohshima; Mareomi Hamada

Takotsubo cardiomyopathy is a cardiac syndrome characterized by reversible left ventricular wall motion abnormalities. It mimics the acute coronary syndrome; however, significant obstructive coronary artery disease is absent. The prognosis is relatively favorable in many cases, but complications may occur during the acute stage. Herein, we present a case of takotsubo cardiomyopathy in a 76-year-old woman. Three days after admission for persistent chest pains, the patient suddenly developed right hemiplegia, right homonymous hemianopsia, and aphasia. By diffusion-weighted magnetic resonance imaging and magnetic resonance angiography, we diagnosed acute-phase cerebral infarction caused by abrupt occlusion of the left middle cerebral artery by a thrombus, and treated it with intravenously administered tissue plasminogen activator. Three hours afterward, the patients condition improved considerably. She was discharged 15 days after admission without any neurological sequelae. Thus, we show that takotsubo cardiomyopathy complicated by cerebral emboli can be successfully treated using tissue plasminogen activator. <Learning objective: Serious complications sometimes occur during the acute stage of takotsubo cardiomyopathy. Cerebral thromboembolisms are relatively common complications of takotsubo cardiomyopathy that require careful observation during acute phase, and anticoagulant therapy needs to be considered. In case of cerebral emboli, rapid treatment by tissue plasminogen activator infusion may lead to a favorable prognosis.>.

Collaboration


Dive into the Kiyotaka Ohshima'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