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Featured researches published by Naoei Isomura.


Heart and Vessels | 2014

Association between increased epicardial adipose tissue volume and coronary plaque composition

Kennosuke Yamashita; Myong Hwa Yamamoto; Seitarou Ebara; Toshitaka Okabe; Shigeo Saito; Koichi Hoshimoto; Tadayuki Yakushiji; Naoei Isomura; Hiroshi Araki; Chiaki Obara; Masahiko Ochiai

To assess the relationship between epicardial adipose tissue volume (EATV) and plaque vulnerability in significant coronary stenosis using a 40-MHz intravascular ultrasound (IVUS) imaging system (iMap-IVUS), we analyzed 130 consecutive patients with coronary stenosis who underwent dual-source computed tomography (CT) and cardiac catheterization. Culprit lesions were imaged by iMap-IVUS before stenting. The iMAP-IVUS system classified coronary plaque components as fibrous, lipid, necrotic, or calcified tissue, based on the radiofrequency spectrum. Epicardial adipose tissue was measured as the tissue ranging from −190 to −30 Hounsfield units. EATV, calculated as the sum of the fat areas on short-axis images, was 85.0 ± 34.0 cm3. There was a positive correlation between EATV and the percentage of necrotic plaque tissue (R2 = 0.34, P < 0.01), while there was a negative correlation between EATV and the percentage of fibrous tissue (R2 = 0.24, P < 0.01). Multivariate analysis revealed that an increased low-density lipoprotein cholesterol level (β = 0.15, P = 0.03) and EATV (β = 0.14, P = 0.02) were independently associated with the percentage of necrotic plaque tissue. An increase in EATV was associated with the development of coronary atherosclerosis and, potentially, with the most dangerous type of plaque.


Esc Heart Failure | 2016

Steroid pulse therapy was effective for cardiac sarcoidosis with ventricular tachycardia and systolic dysfunction

Toshitaka Okabe; Tadayuki Yakushiji; Michiaki Hiroe; Yuji Oyama; Wataru Igawa; Morio Ono; Takehiko Kido; Seitaro Ebara; Kennosuke Yamashita; Myong Hwa Yamamoto; Shigeo Saito; Koichi Hoshimoto; Amemiya Kisaki; Naoei Isomura; Hiroshi Araki; Masahiko Ochiai

A 32‐year‐old man presented with palpitation. He was diagnosed with pulmonary sarcoidosis by lung biopsy. The electrocardiogram showed first‐degree atrioventricular block and complete right bundle branch block (CRBBB). We planned to examine laboratory data, echocardiography, Holter monitoring, and gallium‐67 scintigraphy. Before he went through all these exams, he developed ventricular tachycardia. After defibrillation was performed, his electrocardiogram revealed complete atrioventricular block. We observed elevation of serum angiotensin‐converting enzyme levels. In addition, both of gallium‐67 scintigraphy and 18F‐fluorodeoxyglucose positron emission tomography showed abnormal uptake in the ventricular septum. We diagnosed the patient with cardiac sarcoidosis associated with these arrhythmias. We started treatment with methylprednisolone pulse therapy (1 g daily). After 3 days of steroid pulse therapy, we administered prednisolone 30 mg daily. On day 15, electrocardiogram changed from complete atrioventricular block to first‐degree atrioventricular block and CRBBB. He was discharged with no progression with cardiac sarcoidosis for 2 years.


International Journal of Cardiology | 2017

Relationship between worsening renal function and long-term cardiovascular mortality in heart failure patients

Toshitaka Okabe; Tadayuki Yakushiji; Takehiko Kido; Yuji Oyama; Wataru Igawa; Morio Ono; Seitaro Ebara; Kennosuke Yamashita; Myong Hwa Yamamoto; Shigeo Saito; Kisaki Amemiya; Naoei Isomura; Hiroshi Araki; Masahiko Ochiai

BACKGROUND Recently several studies showed that worsening renal function (WRF) during hospitalization might be a strong independent predictor of poor prognosis in decompensated heart failure (HF) patients. However, these studies had a relatively short follow-up duration and their data were limited to in-hospital outcomes. Our purpose was to assess the relationship between WRF and long-term cardiovascular mortality in HF patients. METHODS We enrolled decompensated HF patients who were admitted to our hospital between April 2010 and March 2015. WRF was defined as a relative increase in serum creatinine of at least 25% or an absolute increase in serum creatinine ≥0.3mg/dL from the baseline. We assessed the cardiovascular mortality and all-cause mortality in HF patients with WRF (WRF group) and without WRF (no WRF group). RESULTS Among 301 patients enrolled, WRF developed in 118 patients (39.2%). During a median follow-up period of 537days [interquartile range, 304.3 to 1025.8days], cardiovascular mortality and all-cause mortality were significantly higher in the WRF group than in the no WRF group (23.2% vs. 6.1%, P<0.001; 30.3% vs. 14.7%, P<0.001, respectively). In the multivariate Cox proportional hazards model, age and serum B-type natriuretic peptide (BNP) level were associated with both cardiovascular death and all-cause death. However, WRF was not the independent predictor of cardiovascular death (P=0.19) nor all-cause death (P=0.57). CONCLUSIONS WRF was associated with cardiovascular death in patients with HF. Although not an independent predictor, WRF might be one of useful markers to identify patients who should be followed carefully after discharge.


Journal of Cardiology Cases | 2014

Local injection of tissue-plasminogen activator using a pulse spray catheter as a treatment option for proximal deep vein thrombosis: A case report

Toshitaka Okabe; Hiroshi Araki; Tadayuki Yakushiji; Seitaro Ebara; Kennosuke Yamashita; Myong Hwa Yamamoto; Shigeo Saito; Koichi Hoshimoto; Kisaki Amemiya; Naoei Isomura; Chiaki Obara; Masahiko Ochiai

A 24-year-old woman was admitted to our hospital with the diagnosis of pulmonary thromboembolism (PTE) and left common iliac vein thrombosis. She had used low-dose contraceptive pill for dysmenorrhea. Otherwise, her laboratory data did not show any other thrombotic risk factors. Thrombus in the common iliac vein usually requires a permanent inferior vena cava (IVC) filter. However, the use of long-term warfarin should have been avoided for her potential future pregnancy. A retrievable IVC filter was placed and catheter directed thrombolysis was performed for her deep vein thrombosis (DVT). Local injection of monteplase from a pulse spray catheter was performed for 4 days. After the catheter-based treatment, the thrombus resolved and the IVC filter was successfully removed on day 19. The patient was discharged on day 21. Warfarin therapy was discontinued 6 months after discharge. <Learning objective: Urokinase is recommended in the guideline of the Japanese Circulation Society. But the dose is much less than those stated in guidelines overseas. Several studies have shown that tissue-plasminogen activator (t-PA) might be more effective than urokinase. We report a case in which local injection of monteplase, a type of long acting t-PA, for DVT was effective in treating PTE and DVT.>.


International Heart Journal | 2018

Association of Epicardial Adipose Tissue Volume and Total Coronary Plaque Burden in Patients with Coronary Artery Disease: Three-Vessel IVUS Analysis

Kennosuke Yamashita; Myong Hwa Yamamoto; Wataru Igawa; Morio Ono; Takehiko Kido; Seitarou Ebara; Toshitaka Okabe; Shigeo Saito; Kisaki Amemiya; Naoei Isomura; Hiroshi Araki; Masahiko Ochiai

The relationship between epicardial adipose tissue volume (EATV) and plaque vulnerability in non-culprit coronary lesions is not clearly understood.Fifty-four consecutive patients/158 lesions with suspected coronary artery disease underwent computed tomography (CT) and 40 MHz intravascular ultrasound imaging (iMap-IVUS) in cardiac catheterization. Cross-sectional CT slices were semiautomatically traced from base to apex of the heart. Using a 3D workstation, EATV was measured as the sum of fat areas (-190 to -30 Hounsfield units [HU]). All coronary vessels were imaged using iMap-IVUS before stenting to analyze coronary plaques as fibrotic, lipidic, necrotic, or calcified tissue.Mean EATV was 73.7 ± 24.6 (range: 30.2 to 131.8) mL. Patients were divided into two groups by mean EATV (group H: n = 27, EATV ≥ 73.7 mL; group L: n = 27, EATV < 73.7 mL). Total luminal volume, total vessel volume, and total plaque volume were significantly larger in group H. Fibrotic plaque and lipidic plaque volumes were also significantly larger in group H. There was a significant negative correlation between EATV and fibrous tissue (r = -0.31, P = 0.02) and a significant positive correlation between EATV and necrotic tissue (r = 0.37, P = 0.007). EATV was related to plaque with vulnerability in the right coronary artery (RCA) (r = 0.57, P = 0.04) and the left anterior descending artery (LAD) (r = 0.53, P = 0.02). In conclusion, increased EATV was associated with the total coronary plaque burden and composition, particularly in the RCA and LAD.


Journal of the American College of Cardiology | 2016

TCT-73 Serial Three-Vessel Optical Coherence Tomography and Intravascular Ultrasound Analysis of Changing Morphologies Associated of Plaque Progression in Patients With Stable Angina Pectoris

Myong Hwa Yamamoto; Kennosuke Yamashita; Mitsuaki Matsumura; Seitarou Ebara; Toshitaka Okabe; Shigeo Saito; Koichi Hoshimoto; Kisaki Amemiya; Tadayuki Yakushiji; Naoei Isomura; Hiroshi Araki; Chiaki Obara; Masahiko Ochiai; Gary S. Mintz; Akiko Maehara

nos: 73 76 TCT-73 Serial Three-Vessel Optical Coherence Tomography and Intravascular Ultrasound Analysis of Changing Morphologies Associated of Plaque Progression in Patients With Stable Angina Pectoris Myong Hwa Yamamoto, kennosuke yamashita, Mitsuaki Matsumura, Seitarou Ebara, Toshitaka Okabe, Shigeo Saito, Koichi Hoshimoto, Kisaki Amemiya, Tadayuki Yakushiji, Naoei Isomura, Hiroshi Araki, Chiaki Obara, Masahiko Ochiai, Gary Mintz, Akiko Maehara Cardiovascular Research Foundation, New York, New York, United States; Showa University Northern Yokohama Hospital, Yokohama, Japan; Cardiovascular Research Foundation, New York, New York, United States; NorthPoint Solutions, LLC; Showa University Northern Yokohama Hospital, Tokyo, Japan; Showa University Northern Yokohama Hospital, Yokohama, Japan; CRF; Showa universty yohohama northern hospital, Yokohama, Japan; Showa University Northern Yokohama Hospital, Yokohama, Japan; Showa University Northern Yokohama Hospital, Yokohama, Japan; Showa Univ. Northern Yokohama Hospital, Yokohama, Japan; Ospedale Sacco Vialba; Showa University Northern Yokohama Hospital, Kanagawa, Japan; Cardiovascular Research Foundation, Washington, District of Columbia, United States; Cardiovascular Research Foundation, New York, New York, United States BACKGROUND OCT morphologies associated with plaque progression are not well-studied. METHODS We used baseline and 8-mo follow-up 3-vessel OCT and IVUS to assess 124 non-culprit lesions (IVUS plaque burden 40%) in 45 pts with stable angina after culprit lesion percutaneous coronary intervention. Plaque progression was defined as IVUS minimum lumen area decrease >0.5mm2. Lipid plaques by OCT were defined as signal-poor regions with diffuse borders. RESULTS Overall, 24/124 plaques progressed and were characterized by OCT as plaque rupture (n1⁄44), new layer appearance (n1⁄47), thickening of fibrous cap (n1⁄47), or no OCT morphological change with negative remodeling by IVUS (n1⁄46, vessel area at baseline 12.2 [9.9, 18.7]mm2 to follow-up; 10.2 [8.0, 18.5]mm2, p1⁄40.17) (Figure). Pts with plaque progression (n1⁄416) reported less statin use (31.3% vs. 72.4%, p1⁄40.007) and higher baseline LDL-C (110.0 vs. 87.0 mg/dL, p1⁄40.007) and hs-CRP (0.097 vs. 0.051 mg/dL, p1⁄40.004). Multivariable logistic regression analysis showed that lipid plaque by OCT was an independent predictor of plaque progression (OR: 10.2, p1⁄40.001). Progression (n[24) Non-progression


Journal of the American College of Cardiology | 2013

THE ASSOCIATION BETWEEN EPICARDIAL FAT VOLUME AND CORONARY ARTERY PLAQUE CHARACTERIZATION

Kennosuke Yamashita; Myong Hwa Yamamoto; Seitarou Ebara; Toshitaka Okabe; Koichi Hoshimoto; Shigeo Saito; Tadayuki Yakushiji; Naoei Isomura; Hiroshi Araki; Chiaki Obara; Masahiko Ochiai

The aim of this study is to assess the relationship of EFV and plaque vulnerability using a 40MHz IVUS imaging system (iMap-IVUS) in significant coronary stenotic lesion. We analysed consecutive 130patients (94men and 36women) with suspected coronary artery disease who underwent dual-source CT (


Journal of Arrhythmia | 2008

Histopathology of the Posterolateral Myocardium in a Responder to Cardiac Resynchronization Therapy

Chiaki Obara; Taka-aki Matsuyama; Yuki Mikoshiba; Naoei Isomura; Kazuhiro Ashida; Hiroshi Araki; Masahiko Ochiai

We present a 72‐year‐old man with idiopathic dilated cardiomyopathy, who was in New York Heart Association class III and had left ventricular (LV) dyssynchrony on tissue Doppler imaging. Cardiac resynchronization therapy (CRT) was performed for his heart failure, which improved to class I. Two years later, ventricular arrhythmias recurred, resulting in death. The LV posterior vein containing a pacing lead showed half‐circumferential fibrous thickening. The LV myocardium of this region was relatively well preserved, and interstitial fibrosis due to cardiomyopathy was mild. Absence of a massive fibrotic scar on the LV posterior wall and positioning of the pacing lead in the optimal coronary vein (a posterolateral vein) might have been positive factors determining this patients response to CRT.


Cardiovascular Therapeutics | 2015

The Efficacy of Tolvaptan in Congestive Heart Failure Patients with and Without Hypoalbuminemia: A Pilot Study

Toshitaka Okabe; Tadayuki Yakushiji; Wataru Igawa; Morio Ono; Takehiko Kido; Seitaro Ebara; Kennosuke Yamashita; Myong Hwa Yamamoto; Shigeo Saito; Koichi Hoshimoto; Kisaki Amemiya; Naoei Isomura; Hiroshi Araki; Masahiko Ochiai


Journal of the American College of Cardiology | 2017

THE IMPACT OF RECANALIZATION OF CHRONIC TOTAL OCCULUDED CORONARY ARTERY ON ELECTROPHYSIOLOGICAL SUBSTRATE OF LEFT VENTRICLE

Kennosuke Yamashita; Masahiko Ochiai; Yuji Oyama; Wataru Igawa; Morio Ono; Takehiko Kido; Seitarou Ebara; Toshitaka Okabe; Myong Hwa Yamamoto; Shigeo Saito; Kisaki Amemiya; Naoei Isomura; Hiroshi Araki

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Shigeo Saito

Columbia University Medical Center

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Tadayuki Yakushiji

Columbia University Medical Center

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