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Dive into the research topics where Masahiko Harada is active.

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Featured researches published by Masahiko Harada.


Journal of Medical Ultrasonics | 2007

Evaluation of left ventricular diastolic function using color kinesis

Masahiko Harada; Kyoko Hayashi; Yuichi Takarada; Hironori Hirai

PurposeColor kinesis (CK) is a real-time echocardiographic technique based on acoustic quantification that yields regional and global information by tracking and color-encoding endocardial motion. The aim of this study was to determine the feasibility and usefulness of diastolic CK images with ICK software to objectively assess global and regional left ventricular (LV) diastolic function. Accordingly, diastolic properties obtained from CK images were compared with conventional Doppler echocardiographic indices.MethodsWe studied 56 subjects who underwent echocardiographic evaluation in our laboratory for assessment of cardiac structure and function. Criteria for inclusion included the presence of normal sinus rhythm and adequate two-dimensional echocardiographic imaging. Exclusion criteria were (1) all types of arrhythmias, (2) pericardial effusion, (3) heart rates <55 or >90 beats/min, (4) abnormal interventricular septal motion caused by right ventricular pressure or volume overload, (5) moderate to severe mitral or aortic regurgitation, and (6) mitral valve stenosis. Using pulsed Doppler echocardiography, peak velocities during rapid filling (E) and atrial contraction (A) were measured, and the E/A ratio and deceleration time of the E wave velocity (DT) were calculated. The time-velocity integral (TVI) of the E wave (TVI-R), A wave (TVI-A), and rapid-filling fraction (TVI-R/TVI-R+TVI-A) was measured. The early diastolic mitral annular velocity (Ea) was measured by tissue Doppler. The 56 subjects were divided into the following three groups: (1) an impaired relaxation group consisting of 30 patients with normal ejection fraction and a mitral inflow pattern with a reduced E/A ratio (E/A < 1.0); (2) a pseudonormal group consisting of 18 patients with a mitral inflow pattern with an increased E/A ratio (E/A > 1.0), an increased E/Ea ratio (E/Ea 10), and no shortened DT (≧140 ms) [patients with hypertrophic cardiomyopathy (HCM, n = 8), dilated cardiomyopathy (DCM, n = 8), and aortic valve stenosis (n = 2) were included in this group); and (3) a restrictive group consisting of eight patients with a mitral inflow pattern with an increased E/A ratio (E/A >1.5), an increased E/Ea ratio (E/Ea ≧10), and a shortened DT (<140 ms) [patients with DCM (n = 5) and HCM (n = 3) were included in this group]. As a control group, 20 normal subjects (30 ± 18 years) were selected on the basis of having high-quality echocardiographic images. Diastolic CK images were obtained from the LV midpapillary short-axis view. The analysis of CK diastolic images was performed by using ICK software. The CK-diastolic index (CK-DI) was defined as the degree of LV segmental expansion during the first 30% of diastole, expressed as a percentage. The mean CK-DI was calculated from the average CK-DI of six LV segments.ResultsNo relationship was observed between mean CK-DI and rapid-filling fraction in any of the study subjects (r = −0.092, P > 0.2). Mean CK-DI was significantly lower in the restrictive group (34.2% ± 4.3%) compared with the normal group (70.6% ± 7.4%), the impaired relaxation group (50.5% ± 7.7%), and the pseudonormal group (42.3% ± 7.5%). The reduction of mean CK-DI was found to be associated with the progression of LV diastolic dysfunction.ConclusionWe conclude that the analysis of diastolic CK by using ICK software is a useful technique that can be applied to quantitative evaluation of LV global diastolic function.


Journal of Medical Ultrasonics | 2009

Assessment of left ventricular diastolic function using color kinesis: differentiation between normal and pseudonormalized patterns

Masahiko Harada; Fumihiko Hara; Kyoko Hayashi; Yuichi Takarada

PurposeDoppler examination of transmitral flow has been widely used to noninvasively assess left ventricular (LV) diastolic function. However, it has been demonstrated that transmitral flow velocity is dependent on LV relaxation and left atrial pressure. Increases in left atrial pressure compensate for the effects of impaired LV relaxation, frequently resulting in a “pseudonormalization” of the transmitral flow pattern. The purpose of this study was to assess whether analysis of diastolic color kinesis (CK) can be applied to differentiation between normal and pseudonormalized (PN) patterns of LV inflow.MethodsWe studied 60 subjects with a ratio of early to late transmitral peak velocities (E/A) greater than 1.0 according to conventional Doppler echocardiography. All subjects simultaneously underwent measurement of the early diastolic mitral annular velocity (e′), which was measured by tissue Doppler imaging, and LV ejection fraction (EF), which was calculated by the modified Simpson method. Study subjects were classified into the following three groups according to the value of e′ and EF: (1) the normal group (e′ > 10 cm/s, EF > 60%), including 20 subjects (mean age 35 ± 10 years); (2) the PN1 group (e′ < 7 cm/s, EF > 50%), consisting of 20 patients [mean age 63 ± 11 years, 15 patients with hypertensive heart disease (HHD), 5 patients with aortic valve stenosis]; and (3) the PN2 group (e′ < 7 cm/s, EF < 50%), consisting of 20 patients (mean age 61 ± 17 years, 18 patients with dilated cardiomyopathy, 2 patients with HHD). Diastolic CK images were obtained for each subject from the LV midpapillary short-axis view. Analysis of CK diastolic images was performed using ICK software. The CK-diastolic index (CK-DI) was defined as the calculated LV segmental filling fraction during the first 30% of diastole, expressed as a percentage. The mean CK-DI was determined from the average CK-DI of six LV segments.ResultsThe mean CK-DI was 70.9% ± 6.5% in the normal group, 46.3% ± 10.4% in the PN1 group, and 36.3% ± 5.1% in the PN2 group. The mean CK-DI was significantly reduced in the PN1 and PN2 groups compared with the normal group (P < 0.0001). Although there was no difference in e′ (PN1 group: 4.6 ± 1.8 cm/s, PN2 group: 4.4 ± 1.7 cm/s) between the two pseudonormalized patient groups, the mean CK-DI was significantly reduced in the PN2 group compared with the PN1 group (P < 0.005). The reduction in mean CK-DI was seen not only in pseudonormalized patients with LV systolic dysfunction but also in those with preserved LV systolic function.ConclusionThe analysis of diastolic CK with ICK software is a useful method for detecting delayed early diastolic relaxation. We concluded that diastolic CK images may be applied to differentiating between normal and pseudonormalized patterns of LV inflow.


Cardiovascular Intervention and Therapeutics | 2012

Transcatheter atrial septal defect closure in a patient with paradoxical brain emboli: who should treat it and who should be treated?

Hidehiko Hara; Tomotaka Nakayama; Hiroyuki Matsuura; Kaori Sato; Go Hashimoto; Hisao Yoshikawa; Makoto Suzuki; Fumihiko Hara; Masahiko Harada; Kenji Wagatsuma; Kaoru Sugi; Tsutomu Saji; Masato Nakamura

This report presents the case of a 51-year-old female who was admitted to a local hospital because of a persistent headache. A diagnosis of multiple cerebral infarctions was thereafter made, but there was no evidence of either atherosclerosis or atrial fibrillation. The case was thought to be a cryptogenic stroke, however, Doppler ultrasonography of the lower extremities showed venous insufficiency. Transesophageal echocardiography revealed a secundum atrial septal defect (ASD) with a left to right shunt. Therefore, the final diagnosis was paradoxical brain emboli, and transcatheter ASD closure was successfully performed by cardiologists without any sequelae.


International Heart Journal | 2018

Comparison of Direct Oral Anticoagulants and Warfarin in the Treatment of Deep Venous Thrombosis in the Chronic Phase: A Large, Single-Center, Observational Study

Shingo Wakakura; Fumihiko Hara; Tadashi Fujino; Asami Hamai; Hiroshi Ohara; Takayuki Kabuki; Masahiko Harada; Takanori Ikeda

We assessed the efficacy and safety of direct oral anticoagulants (DOACs) for the treatment of deep venous thrombosis (DVT) in the chronic phase through comparison with conventional warfarin therapy.A total of 807 consecutive patients who were diagnosed with having DVT in the chronic phase were included (484 patients to warfarin therapy and 323 patients to DOAC therapy). The condition of leg veins was assessed 3 to 6 months after starting the therapies by ultrasound examination. Major bleeding and mortality during the therapies were followed-up.There was no significant difference between the two groups in the thrombosis improvement rate (DOAC group: 91.2% versus warfarin group: 88.9%). There was no significant difference between the two groups in major bleeding (DOAC group: 1.8% versus warfarin group: 1.8%). In patients with active cancer, the DOAC group had a borderline higher thrombosis improvement rate than the warfarin group (92.1% versus 80.0%, P = 0.05). The proportion of major bleeding in the patients with active cancer was slightly higher in the warfarin group than in the DOAC group (4.3% versus 2.8%; P = 0.71). Active cancer was not an independent risk factor for major bleeding and recurrence in the DOAC group (OR 2.68, 95% CI 0.51-14.1; P = 0.24 and OR 0.65, 95% CI 0.20-2.07; P = 0.47).In treatment using oral anticoagulants for DVT in the chronic phase, DOACs exhibited equal efficacy and safety as warfarin did. Particularly DOACs appear to be an attractive therapeutic option for cancer-associated DVT in chronic phase, with relatively low anticipated rates of recurrence and major bleeding.


Journal of Echocardiography | 2016

Response to Dr. Sani’s letter to the editor

Masahiko Harada; Satoshi Tabako

We appreciate the interesting comments of Dr. Sani and his colleagues regarding our recent article [1]. We used a logistic regression model for data analysis. This method is usable in a clinical investigation designed to retrospectively detect factor(s) predicting a certain dichotomous variable [2]. The present study demonstrated that decreased early diastolic mitral annular velocity relates to the parameter reflecting carotid atherosclerosis. Therefore, the presence of severe carotid atherosclerosis may affect left ventricular (LV) diastolic function. We never show optimistic conclusions that early diastolic mitral annular velocity (é) is the only predictor of the presence of severe carotid atherosclerosis. For the patient with LV diastolic dysfunction, it is important that we pay more attention to the presence of generalized atherosclerosis. Carotid ultrasonography is useful in assessing the degree of generalized atherosclerosis. We should also try to the prevention of cardiovascular disease for those patients.


Journal of Medical Ultrasonics | 2002

A case of chronic dissecting aortic aneurysm complicated with rupture into the right atrium: Diagnosis by transesophageal echocardiography

Masahiko Harada; Hironori Hirai; Tetsuo Lee; Takuya Inoue; Hideyuki Sakai; Yuko Sugiyama; Makoto Suzuki; Tetsu Yamaguchi

Although rupture of a dissecting aortic aneurysm into the pericardial sac, pleural cavities, or mediastinum is a frequently encountered complication of this entity, rupture into a right-sided cardiac chamber is extremely rare. An 80-year-old woman was admitted to this institution because of dyspnea and facial edema. One year before admission, a diagnosis of dissecting aortic aneurysm (Stanford A type) was made based on results of magnetic resonance imaging and transesophageal echocardiography (TEE); however, the patient and her family refused surgical therapy. On admission, blood pressure was 120/60 mmHg, and a Levine 3/6° continuous murmur was audible at the third and fourth intercostal spaces of the right sternal border. Chest x-ray film showed moderate cardiomegaly, congested lung fields, and bilateral pleural effusion. A two-dimensional echocardiogram revealed severe aortic root dilatation 80 mm in diameter with the intimal flap. Color flow Doppler imaging demonstrated abnormal flow toward the back space in dilated ascending aorta. Continuous wave Doppler imaging showed the peak velocity of this flow to be 4.8 m/s. This high-velocity flow strongly suggested that the dissecting aortic aneurysm had ruptured into the right-sided cardiac chamber, and shunt flow from the false lumen of the aortic aneurysm into the right atrium was directly visualized by TEE. Our diagnosis, based on these findings, was chronic dissecting aortic aneurysm with communication into the right atrium. In view of the patient’s deteriorating clinical condition, cardiac catheterization was not performed before surgery. Surgery revealed an aneurysm of the ascending aorta measuring 90 mm in diameter and multiple fistulas approximately 2 to 3 mm in diameter arising from the false lumen of the aorta into the right atrium at the base of the atrial appendage. The patient underwent successful replacement of the ascending aorta and closure of the aorto-right atrial fistulas. She had an uneventful postoperative course and was discharged 7 weeks after surgery.


Circulation | 2009

Correlation Between Left Ventricular Diastolic Function and Ejection Fraction in Dilated Cardiomyopathy Using Magnetic Resonance Imaging With Late Gadolinium Enhancement

Shuji Nanjo; Kohki Yoshikawa; Masahiko Harada; Yusuke Inoue; Atsushi Namiki; Hajime Nakano; Junichi Yamazaki


Journal of Cardiology | 2010

Correlation between plasma B-type natriuretic peptide levels and left ventricular diastolic function using color kinetic imaging.

Masahiko Harada; Fumihiko Hara; Junichi Yamazaki


Journal of Cardiology | 1998

[Aortic and mitral valve aneurysms complicated with infective endocarditis: a case report].

Masahiko Harada; Hironori Hirai; Inoue T; Sakai H; Lee T; Yuko Sugiyama; Makoto Suzuki; Kamezaki M; Tamura S; Shiroma K; Ebine K; Takahashi K; Naoe S; Tetsu Yamaguchi


Journal of Echocardiography | 2016

Carotid atherosclerosis is associated with left ventricular diastolic function.

Masahiko Harada; Satoshi Tabako

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