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Featured researches published by Rei Yajima.


International Journal of Cardiology | 2012

Distinguishing focal fibrotic lesions and non-fibrotic lesions in hypertrophic cardiomyopathy by assessment of regional myocardial strain using two-dimensional speckle tracking echocardiography: Comparison with multislice CT

Rei Yajima; Akihisa Kataoka; Akiyo Takahashi; Masae Uehara; Mariko Saito; Chiharu Yamaguchi; Kwangho Lee; Issei Komuro; Nobusada Funabashi

PURPOSE To distinguish focal fibrotic and non-fibrotic lesions in left-ventricular myocardium (LVM) in hypertrophic-cardiomyopathy (HCM)-subjects, we compared myocardial regional peak-strain values using two-dimensional speckle-tracking transthoracic-echocardiography (TTE) in multislice computed-tomography (CT)-detected fibrotic, non-fibrotic and normal control lesions. METHODS Twenty subjects (10 consecutive HCM-subjects (8-males, mean 63.4-years), 10 healthy controls (5-males, mean 51.5-years)) underwent speckle-tracking TTE (iE-33), and analysis of regional peak-longitudinal (LS) and radial-strain (RS), and corresponding strain rates in each of 17 LVM segments (American-Heart-Association classification). In HCM-subjects, fibrotic lesions were identified by early-phase defective enhancement and late-phase abnormal enhancement by CT (Light-Speed-Ultra-16). Regional peak LS and RS at basal, mid and apical levels were measured in MSCT-detected fibrotic and non-fibrotic LVM lesions. RESULTS In 10 HCM subjects, 143 lesions (84.1%) yielded good tracking on TTE. Twenty lesions showed fibrotic changes in 5 subjects by CT. Regional peak-LS and RS absolute values were significantly lower in both fibrotic and non-fibrotic lesions in HCM subjects than in controls at basal, mid, apical levels (all P<0.05). While peak-LS (%) absolute values were significantly lower in fibrotic than non-fibrotic lesions at basal, mid and apical levels (all P<0.05), regional peak-RS absolute values were significantly lower only at mid levels. LS was a more sensitive indicator than the corresponding rate, with better reproducibility. CONCLUSIONS In HCM, regional peak-LS was significantly lower in fibrotic than non-fibrotic lesions in LVM by CT. Regional peak-LS by speckle-tracking provides useful information noninvasively to distinguish fibrotic from non-fibrotic lesions in LVM in HCM and normal LVM in healthy controls.


International Journal of Cardiology | 2011

Quantitative evaluation of left atrial volumes and ejection fraction by 320-slice computed-tomography in comparison with three- and two-dimensional echocardiography: A single-center retrospective-study in 22 subjects

Akihisa Kataoka; Nobusada Funabashi; Akiyo Takahashi; Rei Yajima; Maiko Takahashi; Masae Uehara; Hiroyuki Takaoka; Mariko Saito; Chiharu Yamaguchi; Kwangho Lee; Fumio Nomura; Issei Komuro

PURPOSE To evaluate efficacy and reproducibility of 320-slice computed tomography (CT) for measuring left atrial (LA) maximum (LAVmax) and minimum volume (LAVmin) during the cardiac cycle, we compared CT with three- and two-dimensional (3D and 2D) transthoracic echocardiogram (TTE). MATERIALS AND METHODS LAVmax and LAVmin (ml), and LA ejection fraction (LAEF) (%) were assessed in 22 consecutive subjects (15 males, 59.5 ± 15.1 years) using retrospective electrocardiogram gated 320-slice CT (Aquilion One, Toshiba Medical) and 3D-TTE (IE-33, Phillips). LAVmax and LAVmin were selected from the time volume curve. LAEF was calculated as (LAVmax-LAVmin)/LAVmax×100(%). RESULTS Mean ± standard deviation (SD) of LAVmax and LAV min were significantly larger by CT than 3D-TTE or 2D-TTE (both P<0.01). LAEF was 25.3 ± 13.1% by CT, 30.2 ± 6.8% by 3D-TTE (P=NS) and 33.9 ± 8.9% by 2D-TTE (P<0.05). The correlation coefficients (CCs) between CT and 3D-TTE in LAVmax, LAmin, and LAEF were 0.64, 0.68 and 0.57, respectively. Mean difference ± 1.96SD of LAVmax, LAVmin and LAEF by Bland and Altman analysis calculated from CT minus 3D-TTE were 48.8 ± 59.1 ml, 41.1 ± 63.2 ml, and -4.9 ± 21.1%, respectively. The CCs and mean difference ± 1.96SD between CT and 2D-TTE had similar tendencies. The CCs of interobserver variation were (for CT, 3D-TTE, 2D-TTE, respectively): 0.90, 0.95 and 0.94 (LAVmax), 0.97 and 0.97 and 0.93 (LAVmin), and 0.64, 0.77 and 0.34 (LAEF). CONCLUSIONS 320-slice CT enables direct LAV measurements and has high reproducibility and positive correlation with 3D and 2D TTE. Absolute value of LAV by CT was larger than that by 3D and 2D TTE.


International Journal of Cardiology | 2011

Quantitative evaluation of right atrial volume and right atrial emptying fraction by 320-slice computed tomography compared with three-dimensional echocardiography

Akiyo Takahashi; Nobusada Funabashi; Akihisa Kataoka; Rei Yajima; Maiko Takahashi; Masae Uehara; Hiroyuki Takaoka; Mariko Saito; Chiharu Yamaguchi; Kwangho Lee; Issei Komuro; Fumio Nomura

[3] Miwa K, Fujita M. “Small heart syndrome” in patients with chronic fatigue syndrome. Clin Cardiol 2008;31:328–33. [4] Miwa K, Fujita M. Cardiac function fluctuates during exacerbation and remission in young adults with chronic fatigue syndrome and “small heart”. J Cardiol 2009;54: 29–35. [5] Miwa K, Fujita M. Cardiovascular dysfunction with low cardiac output due to small heart in patients with chronic fatigue syndrome. Inter Med 2009;48: 1849–54. [6] Coats AJ. Ethical authorship and publishing. Int J Cardiol 2009;131:149–50.


International Journal of Cardiology | 2009

Right atrium contractility and right ventricular diastolic function assessed by pulsed Tissue Doppler Imaging can predict brain natriuretic peptide in adults with acquired pulmonary hypertension

Yumi Shiina; Nobusada Funabashi; Kwangho Lee; Masao Daimon; Tai Sekine; Miyuki Kawakubo; Maiko Takahashi; Rei Yajima; Nobuhiro Tanabe; Takayuki Kuriyama; Issei Komuro

PURPOSE We evaluated right atrial (RA) contractility and right ventricular (RV) diastolic function in adult patients with acquired chronic pulmonary hypertension (PH) by pulsed Tissue Doppler Imaging (TDI) and assessed their relationship with serum brain natriuretic peptide (BNP). MATERIALS AND METHODS Systolic myocardial wave (Sa), early diastolic myocardial wave (Ea), and late diastolic myocardial wave (Aa) at the tricuspid annulus were recorded in 77 consecutive patients with acquired PH. Early (E) RV inflow waves were recorded from 4-chamber views. RV Aa was regarded as the parameter of RA contractility and RV E/Ea was taken as the parameter of RV diastolic function using TDI. RESULTS All subjects had elevated BNP (mean 188.9 +/- 244.0 pg/dl) and pulmonary arterial systolic pressure (PASP) estimated at 62.9 +/- 26.7 mm Hg. BNP levels were positively correlated with RV E/Ea, Aa and PASP (r = 0.47, p < 0.0001 and r = 0.35, p < 0.01, respectively) but negatively with Aa (r = -0.29, p < 0.05). Next, all predictor variables were used in a multiple regression model with serum BNP values as dependent variables, refined to include 3 predictors: RV E/Ea, Aa, and PASP, which were all found to influence serum BNP values (p < 0.0001) by the formula Y = 34.1X1**-19.11X2**+2.95X3* (**p < 0.001, *p < 0.01) where Y = BNP, X1 = E/Ea of RV, X2 = Aa, and X3 = PASP (standard regression coefficients were 0.37, -0.34 and 0.34, respectively). CONCLUSION Serum BNP correlates with RA contractility and RV diastolic dysfunction by RV TDI in adults with acquired PH. Increased BNP may be related to decreased RA systolic function and RV diastolic function in these patients.


International Journal of Cardiology | 2010

Comprehensive evaluation of characteristics of left ventricular myocardium in a subject with non-coronary arterial cardiac dysfunction through segment by segment analysis using various diagnostic modalities

Hisako Ono; Nobusada Funabashi; Masae Uehara; Rei Yajima; Akihisa Kataoka; Marehiko Ueda; Hideyuki Miyauchi; Michiko Daimon; Hiroyuki Takaoka; Issei Komuro

We performed segment by segment analysis for comprehensive evaluation of the characteristics of the left ventricular (LV) myocardium by multislice CT (MSCT), magnetic resonance imaging (MRI), single photon emission computed tomography (SPECT) and positron emission tomography (PET) in a patient with non-coronary arterial cardiac dysfunction. If diagnosis had been performed only by transthoracic echocardiogram and conventional coronary angiography, this subject might have been diagnosed as having dilated cardiomyopathy. However, we succeeded in the detailed evaluation of characteristics of LV myocardium non-invasively. Because of the difference in spatial resolution, MSCT and MRI could only detect focal fibrosis and MSCT could only detect fatty changes in the LV myocardium with an accurate ratio of thickness of lesions in comparison with the thickness of the whole LV myocardium. Conversely, a drawback of PET and SPECT was the partial volume effect and these methods could visualize the lesions as only diffuse decrements of attenuation and could not provide detailed information. Furthermore in MSCT, LV wall motion abnormality could be visualized by showing the ribs, sternum and descending aorta and in particular MSCT could obtain much information, including extra cardiac findings.


International Journal of Cardiology | 2011

Differentiation of pseudodyskinesis of inferior left ventricular wall from inferior myocardial infarction by assessment of regional myocardial strain using two-dimensional speckle tracking echocardiography.

Akihisa Kataoka; Nobusada Funabashi; Rei Yajima; Maiko Takahashi; Akiyo Takahashi; Mariko Saito; Chiharu Yamaguchi; Taro Imaeda; Kwangho Lee; Issei Komuro

PURPOSE To differentiate pseudodyskinesis (PD) of the inferior left ventricular (LV) wall from inferior myocardial infarction (IMI) noninvasively, we performed focal site evaluation using two-dimensional speckle tracking transthoracic echocardiography (TTE). MATERIALS AND METHODS Speckle tracking TTE was carried out in 57 patients, with 19 subjects in each of three groups (Group A, suspected PD; Group B, LV IMI; and Group C, controls). Inferior wall PD was defined as follows: compression of the inferior LV wall by the diaphragm in the LV short axis view with a normal electrocardiogram and no evidence of previous ischemic events. RESULTS Respective values in Groups A-C for LV ejection fraction (EF) were 63.6 ± 4.2%, 52.3 ± 7.6%, and 61.5 ± 3.8%, for inferior wall speckle tracking focal site evaluation peak radial strain of 30.0 ± 14.3%, 7.5 ± 7.1%, and 42.1 ± 22.9%, for peak circumferential strain of 23.1 ± 6.0%, 16.8 ± 8.4%, and 22.7 ± 7.1%, and for longitudinal strain in the mid-inferior wall of 18.4 ± 3.4%, 11.4 ± 4.0% and 15.8 ± 5.9%. LVEF values were significantly lower in Group B than Groups A and C (P<0.001), as were those of radial, circumferential, and longitudinal strains (P<0.05). In receiver-operating characteristic analysis the optimal cut-off values with corresponding sensitivities and specificities for differentiation of PD from IMI were >19% with 84.2% and 94.7% for radial, >15% with 89.4% and 52.6% for circumferential, and >15% with 73.6% and 100% for longitudinal strain, respectively. CONCLUSIONS Determination of regional strain from speckle tracking TTE, especially radial and longitudinal strains, can provide focal and quantitative noninvasive evaluation for distinguishing PD of the inferior wall from IMI.


International Journal of Cardiology | 2013

Efficiency of quantitative longitudinal peak systolic strain values using automated function imaging on transthoracic echocardiogram for evaluating left ventricular wall motion: New diagnostic criteria and agreement with naked eye evaluation by experienced cardiologist

Maiko Takahashi; Nobuhiro Harada; Yuka Isozaki; Kwangho Lee; Rei Yajima; Akihisa Kataoka; Mariko Saito; Akiyo Kanaeda; Chiharu Yamaguchi; Tomoko Kamata; Koya Ozawa; Akiko Tani; Sawako Horie; Tomoko Umazume; Yoshio Kobayashi; Nobusada Funabashi

PURPOSE To evaluate the efficiency of automated function imaging (AFI) on transthoracic echocardiogram (TTE) for detecting left ventricular (LV) wall motion (LVWM) abnormalities, we compared longitudinal peak systolic strain (LPSS) measurements using AFI with naked eye TTE evaluations by experienced cardiologists and non-experienced residents. MATERIALS AND METHODS A total of 352 segments of LV myocardium from 22 consecutive subjects with LVWM abnormalities based on American Heart Association classifications (11 male, mean age 58 ± 14 years) on previous TTE (Vivid-7, GE) were evaluated. LPSS was measured using stored AFI data. Naked eye evaluation of LVWM was performed by 2 experienced cardiologists and 2 non-experienced residents. RESULTS AFI successfully tracked 342 (97%) of all segments (mean LPSS -14.8 ± 8.1%). A significant strong negative correlation was observed between LV ejection fraction using method of disks and global LPSS (R=-0.8974). Temporary AFI criteria of LPSS were normal <-12; hypokinesis -12-2; and akinesis >2. Of 342 segments, 239, 87, and 16 segments were diagnosed as normal, hypokinesis, and akinesis, respectively. Level of agreement and kappa coefficients between qualitative evaluation of LVWM by AFI temporary criteria and qualitative evaluation of LVWM by experienced cardiologist 2 (0.784 and 0.479, respectively) were inferior to those comparing experienced cardiologists (0.845 and 0.595) but superior comparing experienced cardiologist with non-experienced resident (0.696 and 0.323), and between the 2 non-experienced-residents (0.682 and 0.347). CONCLUSION Qualitative evaluation of LVWM using temporary AFI criteria had a 97% success rate and agreed well with findings of an experienced cardiologist. AFI can be a useful tool for training residents.


International Journal of Cardiology | 2010

Differentiation of diagnosis and prognoses of non-coronary arterial primary myocardial diseases with left ventricular focal myocardial thinning evaluated by multislice computed tomography

Nanae Yoshida; Nobusada Funabashi; Masae Uehara; Rei Yajima; Akihisa Kataoka; Marehiko Ueda; Hiroyuki Takaoka; Issei Komuro

PURPOSE This study sought to differentiate diagnosis and prognoses of non-coronary arterial primary myocardial diseases with focal left ventricular myocardial (LVM) thinning evaluated by multislice-CT. Based on the presence of fibro-fatty change and asynergy in LVM, we sought to understand the clinical significance of detection of non-coronary arterial focal LVM thinning. MATERIALS-AND-METHODS 766 consecutive subjects (419--male, 59±18 years) underwent enhanced ECG-gated multislice-CT. 12 subjects (8 male, mean age 58 years) with non-coronary arterial primary diseases and evidence of focal LVM thinning were selected. Non-coronary arterial primary diseases exhibiting focal LVM thinning were defined as follows: In comparison with the adjoining reference normal area, focal LVM thinning in end-diastole was less than half that of the adjoining reference normal area. RESULTS On transthoracic echocardiography, LV sizes of the 12 subjects tended to be slightly enlarged and the mean LV ejection fraction (46.8%) was slightly below the normal range. There are many non-coronary arterial primary diseases which exhibit focal LVM thinning. In this study, we constructed a differential flowchart in which estimation of final diagnosis, treatment and prognosis for such subjects can usefully be based on the presence of fibro-fatty change and asynergy in thinned LVM sites by MSCT. Detection of the presence of fibro-fatty change and asynergy in thinned LVM sites may indicate the need for implantation of implantable cardioverter defibrillator or cardiac pacemakers. CONCLUSION A differential flowchart for those subjects using the presence of fibro-fatty change and asynergy in thinned LVM sites by MSCT may be useful to differentiate prognoses of such subjects.


International Journal of Cardiology | 2009

Doppler imaging predicts cardiac events in chronic pulmonary thromboembolism

Yumi Shiina; Nobusada Funabashi; Kwangho Lee; Masao Daimon; Tai Sekine; Miyuki Kawakubo; Yukiko Sekine; Maiko Takahashi; Rei Yajima; Yu Wakatsuki; Nobuhiro Tanabe; Takayuki Kuriyama; Issei Komuro

PURPOSE We evaluated whether right ventricular (RV) diastolic dysfunction assessed by pulsed tissue Doppler imaging (TDI) predicts cardiac events in patients with chronic pulmonary thromboembolism (CPTE). MATERIALS AND METHODS In 63 consecutive patients with CPTE, early diastolic myocardial velocity (Ea) at the tricuspid annulus by TDI and early diastolic tricuspid inflow (E) by conventional pulsed Doppler were obtained, and E/Ea was calculated as an indicator of RV diastolic dysfunction. Brain natriuretic peptide (BNP) and other echo parameters were also obtained. A cardiac event (rehospitalization caused by congestive heart failure or cardiac death) was the study endpoint. Incidence of cardiac events was determined over a 374+/-451 day follow-up period. RESULTS In the follow-up period twelve patients had cardiac events. We divided patients into group A with cardiac events and group B without events. E/Ea was significantly increased in group A as compared with group B (8.3+/-4.1 vs. 5.7+/-2.6, p<0.01). BNP was higher in group A than group B (221+/-191 vs. 121+/-140 mg/dl, p<0.05), and in addition E/Ea was significantly positively correlated with BNP (r=0.48, p<0.001). A logistic regression model for predicting cardiac events was constructed and E/Ea was associated with an increased incidence of cardiac events (relative risk=1.33, 95% CI 1.00-1.75). CONCLUSION Elevated values of E/Ea obtained by TDI may predict cardiac events in patients with CPTE. BNP may also be a significant predictor.


International Journal of Cardiology | 2009

Left atrial compensatory function in subjects with early stage primary hypertension assessed by using left atrial volumetric emptying fraction acquired by transthoracic echocardiography

Yu Wakatsuki; Nobusada Funabashi; Yoko Mikami; Yumi Shiina; Miyuki Kawakubo; Maiko Takahashi; Rei Yajima; Masae Uehara; Hiroyuki Takaoka; Issei Komuro

PURPOSE To evaluate left atrial (LA) function in subjects with early stage primary hypertension (HT) and without enlargement of LA, we used transthoracic echocardiogram and measured LA volumetric emptying fraction and compared the results with those in healthy volunteers. MATERIALS AND METHODS 42 subjects with early stage primary HT (21 males, aged 61+/-12 years), within 1 year of HT diagnosis and starting initial treatment, were enrolled in the study. An additional inclusion criterion was normal sinus rhythm electrocardiogram without enlargement of LA. As the control group, 31 healthy volunteers with normal sinus rhythm electrocardiogram (13 male, aged 57+/-11 years) were enrolled. Maximum and minimum volume of LA (LAV max and min, respectively) were selected manually and visually in B mode images acquired from a four-chamber view from apex of left ventricle (LV) using a modified Simpson method, and the LA emptying fraction (LAEF) was calculated by the following formula: LAV min/LAV max x 100 (%). RESULTS There were no significant differences in age, male:female ratio, end-diastolic and end-systolic LV diameter, LA maximum volume, LV ejection fraction and E/A in mitral annulus between the two groups. However, we found that end-diastolic inter-ventricular septum thickness and end-diastolic LV posterior wall thickness were significantly larger in the HT group in comparison with the control group (P<0.01), but the HT group did not fit the classical criteria of LV myocardial hypertrophy. The systolic and diastolic blood pressure, the end-diastolic and end-systolic volume of LV, the total weight of LV myocardium and the LAEF were significantly higher in the HT group than in the control group (P<0.05). CONCLUSIONS In subjects with early stage primary HT with normal sinus rhythm, in spite of a normal LAV, the LAEF may increase. This increase of LAEF may be regarded as one of the compensatory reactions against preload to the left side of the heart and precedes the occurrence of LA enlargement.

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