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Dive into the research topics where Yoshiki Matsumura is active.

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Featured researches published by Yoshiki Matsumura.


Circulation | 2006

Three-Dimensional Geometry of the Tricuspid Annulus in Healthy Subjects and in Patients With Functional Tricuspid Regurgitation A Real-Time, 3-Dimensional Echocardiographic Study

Shota Fukuda; Giuseppe Saracino; Yoshiki Matsumura; Masao Daimon; Hung Tran; Neil L. Greenberg; Takeshi Hozumi; Junichi Yoshikawa; James D. Thomas; Takahiro Shiota

Background— Most rings currently used for tricuspid valve annuloplasty are formed in a single plane, whereas the actual tricuspid annulus (TA) may have a nonplanar or 3-dimensional (3D) structure. The purpose of this study was therefore to investigate the 3D geometry of the TA in healthy subjects and in patients with functional tricuspid regurgitation (TR). Methods and Results— This study consisted of 15 healthy subjects and 16 patients with functional TR who had real-time 3D echocardiography. With our customized software, 8 points along the TA were determined with the rotated plane around the axis at 45°intervals. The TA was traced during a cardiac cycle. The distance between diagonals connecting 2 points was measured. The height was defined as the distance from the plane determined by least-squares regression analysis at all 8 points. Both the maximum (7.5±2.1 versus 5.6±1.0 cm2/m2) and minimum (5.7±1.3 versus 3.9±0.8 cm2/m2) TA areas in patients with TR were larger than those in healthy subjects (both P<0.01). Healthy subjects had a nonplanar-shaped TA with homogeneous contraction. The posteroseptal portion was the lowest toward the apex from the right atrium, and the anteroseptal portion was the highest. In patients with functional TR, the TA was dilated in the septal to lateral direction, resulting in a more circular shape than in healthy subjects. A similar 3D pattern was observed in patients with TR, but it was more planar than that in healthy subjects. Conclusions— Real-time 3D echocardiography showed a complicated 3D structure of the TA, which appeared to be different from the “saddle-shaped” mitral annulus, suggesting an annuloplasty for TR different from that for mitral regurgitation.


American Heart Journal | 2008

Geometry of the proximal isovelocity surface area in mitral regurgitation by 3-dimensional color Doppler echocardiography: Difference between functional mitral regurgitation and prolapse regurgitation

Yoshiki Matsumura; Shota Fukuda; Hung Tran; Neil L. Greenberg; Nozomi Wada; Manatomo Toyono; James D. Thomas; Takahiro Shiota

BACKGROUND The geometry of the proximal isovelocity surface area (PISA) of functional mitral regurgitation (MR), which is conventionally assumed to be a hemisphere, remains to be clarified. We investigated the 3-dimensional (3D) geometry of PISA of functional MR as opposed to that of MR due to mitral valve prolapse (MVP) by real-time 3D echocardiography with color Doppler capability. METHODS Twenty-seven patients with functional MR and 27 patients with MVP were examined. The horizontal PISA length in the commissure-commissure plane and each PISA radius in 3 anteroposterior planes (medial, central, and lateral) were measured by real-time 3D echocardiography with 3D software. The effective regurgitant orifice (ERO) area was calculated with the maximum PISA radius and compared to that by 2D quantitative Doppler method. RESULTS En-face 3D color Doppler images showed an elongated and slightly curved PISA geometry along the leaflet coaptation in functional MR, whereas the geometry was rounder in MVP. The PISA horizontal length in functional MR was longer than that in MVP (2.3 +/- 0.4 vs 1.2 +/- 0.2 cm, P < .001). The PISA method with the maximum radius underestimated the ERO area by 2D quantitative Doppler method (by 24%) in functional MR, but not in MVP. CONCLUSIONS The geometry of PISA in functional MR was elongated, distinctly different from the more focal pathology of MVP, leading to underestimation of the ERO area by PISA method.


American Journal of Cardiology | 2010

Echocardiographic predictors for persistent functional mitral regurgitation after aortic valve replacement in patients with aortic valve stenosis.

Yoshiki Matsumura; A. Marc Gillinov; Manatomo Toyono; Hiroki Oe; Tetsuhiro Yamano; Kunitsugu Takasaki; Roberto M. Saraiva; Takahiro Shiota

Moderate functional mitral regurgitation (MR) in patients with aortic valve stenosis (AS) is often left unaddressed at the time of aortic valve replacement (AVR) because it is expected to decrease after AVR. However, some patients have persistent moderate MR after AVR. We sought to determine the preoperative echocardiographic predictor for persistent functional MR after AVR in patients with AS. Pre- and postoperative echocardiograms were reviewed in 110 patients with severe AS and functional MR who underwent AVR without mitral valve (MV) surgery. Fifty-eight patients received concomitant coronary artery bypass graft surgery. In patients with MV tenting, defined as apical displacement of mitral leaflets in the apical 4-chamber view, MV tenting area and tenting height were measured at midsystole. Eighty patients had MV tenting (mean MV tenting area 1.4 +/- 0.5 cm(2), mean MV tenting height 0.8 +/- 0.2 cm) and 30 did not have it before AVR. MR severity decreased in 51 of 80 patients (64%) with MV tenting after AVR and in 25 of 30 patients (83%) without MV tenting (p <0.05). In patients with MV tenting, multivariate analysis revealed that presence of long-term atrial fibrillation and MV tenting area were independent predictors of postoperative MR severity (all p values <0.05). The sensitivity and specificity in predicting persistent moderate MR after AVR were 72% and 82% for MV tenting area >1.4 cm(2). In conclusion, preoperative MV tenting predicts persistent functional MR after AVR in patients with severe AS.


Atherosclerosis | 2010

Elevated levels of neopterin are associated with carotid plaques with complex morphology in patients with stable angina pectoris

Kenichi Sugioka; Takahiko Naruko; Takeshi Hozumi; Masashi Nakagawa; Chizuko Kitabayashi; Yoshihiro Ikura; Nobuyuki Shirai; Yoshiki Matsumura; Shoichi Ehara; Keiji Ujino; Akira Itoh; Kazuo Haze; Anton E. Becker; Minoru Yoshiyama; Makiko Ueda

OBJECTIVE Neopterin is an activation marker for monocytes/macrophages, and circulating levels of neopterin are elevated in patients with coronary complex lesions in unstable angina pectoris. We investigated the possible association between neopterin and complex carotid plaques which may be associated with the risk of ischemic stroke in patients with stable angina pectoris (SAP). METHODS We measured plasma levels of neopterin in 102 patients with SAP and carotid ultrasound was performed for evaluation of the presence of carotid plaques and plaque surface characteristics categorized as complex or noncomplex. In addition, endarterectomy specimens of extracranial high-grade carotid stenosis with complex plaques from five patients with SAP were immunohistochemically examined with antibodies to smooth muscle cells, endothelial cells, platelets, macrophages, and T cells. RESULTS Plasma neopterin levels were significantly higher in patients with complex carotid plaques than in those with noncomplex plaques (median [interquartile range]: 24.2 [19.2-39.3]nmol/L vs. 19.4 [11.9-25.1]nmol/L; P=0.01) or without any plaques (18.8 [14.9-23.6]nmol/L; P=0.001). On multivariate logistic analyses after adjustment for traditional atherosclerotic risk factors, multi-vessel coronary disease and high sensitivity C-reactive protein, neopterin levels were independently associated with the presence of complex carotid plaques (adjusted OR 2.21 per SD increase, 95%CI 1.13-4.33, P=0.02). Immunohistochemical staining revealed abundant neopterin-positive macrophages in carotid complex lesions. CONCLUSION These findings demonstrate that carotid plaques with complex morphology have increased circulating neopterin levels and immunohistochemical localization of neopterin in patients with SAP. Neopterin can be considered an important biomarker of plaque destabilization in carotid artery atherosclerotic lesions in this population.


Heart | 2010

Increased expression and plasma levels of myeloperoxidase are closely related to the presence of angiographically-detected complex lesion morphology in unstable angina

Takahiko Naruko; A. Furukawa; Kei Yunoki; Ryushi Komatsu; Masashi Nakagawa; Yoshiki Matsumura; Nobuyuki Shirai; Kenichi Sugioka; M. Takagi; Takeshi Hozumi; Akira Itoh; Kazuo Haze; Minoru Yoshiyama; Anton E. Becker; Makiko Ueda

Background Myeloperoxidase (MPO) is a leucocyte enzyme that catalyses the formation of a number of reactive oxidant species. Objective The purpose of this study is to evaluate the relationship between angiographic coronary plaque morphology in patients with unstable angina pectoris (UAP) or stable angina pectoris (SAP) and MPO levels. Patients and design Plasma MPO levels on admission were measured in 236 patients with UAP, 146 with SAP and 85 control subjects using an ELISA kit. The angiographic morphology of the culprit lesion was classified into two types, simple or complex, based on the Ambrose classification. In addition, 61 atherectomy specimens obtained from a different cohort of patients with UAP and SAP were studied immunohistochemically for MPO. Results Median (IQR) plasma MPO levels in patients with UAP with a complex lesion were significantly higher than in patients with a simple lesion (41.9 (21.7–73.7) ng/ml vs 20.5 (15.9–27.9) ng/ml, p<0.0001), but there was no significant difference between the two groups in patients with SAP. On multivariate analysis, raised plasma MPO levels and Braunwald class III were independent factors for angiographically-detected complex lesions (adjusted OR 12.49, 95% CI 3.24 to 48.17, p=0.0002). In the atherectomy specimens the number of MPO-positive cells in patients with UAP with complex lesions was significantly higher (p<0.0005) than in patients with simple lesions. Moreover, in this cohort, plasma MPO levels were positively correlated with the number of MPO-positive cells in atherectomy specimens (R=0.42, p=0.024). Conclusions This study shows that increased expression and plasma MPO levels are closely related to the presence of angiographically-detected complex lesion morphology in patients with UAP.


Heart | 2008

Arachidonic acid and docosahexaenoic acid supplementation increases coronary flow velocity reserve in Japanese elderly individuals

Hiroki Oe; Takeshi Hozumi; Eriko Murata; Hitoe Matsuura; Kazuaki Negishi; Yoshiki Matsumura; Shinichi Iwata; Keitaro Ogawa; Kenichi Sugioka; Yasuhiko Takemoto; Kenei Shimada; Minoru Yoshiyama; Yoshiyuki Ishikura; Yoshinobu Kiso; Junichi Yoshikawa

Background: Arachidonic acid (ARA) and docosahexaenoic acid (DHA) are important components of phospholipids and cell membranes. There has, however, been no clinical report on the direct effects of ARA and DHA on coronary circulation. Objective: To evaluate the effects of ARA and DHA on coronary circulation using the measurement of coronary flow velocity reserve (CFVR) by transthoracic Doppler echocardiography (TTDE). Methods: A double-blind, placebo-matched study of 28 Japanese elderly individuals (19 men, mean age 65 years) conducted to compare the effects of polyunsaturated fatty acids (PUFA; ARA 240 mg/day, DHA 240 mg/day) and placebo on CFVR. Coronary flow velocity (CFV) of the left anterior descending coronary artery was measured at rest and during hyperaemia by TTDE to determine CFVR. Results: There were no significant differences in CFV at rest or during hyperaemia in CFVR at baseline in the two groups (PUFA versus placebo 17 (7 SD) versus 16 (6), 62 (20) versus 59 (12), and 3.85 (1.04) versus 3.98 (0.83) cm/s, respectively). After three months’ supplementation, CFV during hyperaemia was significantly higher in the PUFA than in the placebo group (73 (19) versus 64 (12) cm/s, p<0.01) although no significant difference was found between the two groups in CFV at rest (17 (7) versus 16 (4) cm/s). CFVR thus significantly increased after PUFA consumption (3.85 (1.04) versus 4.46 (0.95), p = 0.0023). Conclusion: Three months’ supplementation of PUFA increased CFVR in Japanese elderly individuals, which suggests beneficial effects of PUFA on the coronary microcirculation.


American Journal of Cardiology | 2011

Relation of Aortic Arch Complex Plaques to Risk of Cerebral Infarction in Patients With Aortic Stenosis

Kenichi Sugioka; Yoshiki Matsumura; Takeshi Hozumi; Suwako Fujita; Asahiro Ito; Toru Kataoka; Masahiko Takagi; Kazuki Mizutani; Takahiko Naruko; Mitsuharu Hosono; Hidekazu Hirai; Yasuyuki Sasaki; Makiko Ueda; Shigefumi Suehiro; Minoru Yoshiyama

Aortic stenosis (AS) and systemic atherosclerosis have been shown to be closely related. We evaluated the prevalence of aortic arch plaques and their possible association with the risk of cerebral infarction in patients with severe AS. Transesophageal echocardiography was performed in 116 patients with severe AS (55 men, mean age 71 ± 7 years, mean aortic valve area 0.68 ± 0.15 cm(2)) who were scheduled for aortic valve replacement. The presence, thickness, and morphology of the aortic arch plaques were evaluated using transesophageal echocardiography. Cerebral infarcts (chronic cerebral infarction and cerebral infarction after cardiac catheterization and aortic valve replacement) were assessed in all patients. Compared to age- and gender-matched control subjects, the patients with severe AS had a significantly greater prevalence of aortic arch plaques (74% vs 41%; p <0.0001) and complex arch plaques such as large plaques (≥4 mm), ulcerated plaques, or mobile plaques (30% vs 10%; p = 0.004). Multivariate logistic analyses showed that the presence of complex arch plaques was independently associated with cerebral infarction in patients with AS after adjusting for traditional atherosclerotic risk factors and coronary artery disease (odds ratio 8.46, 95% confidence interval 2.38 to 30.12; p = 0.001). In conclusion, the results from the present study showed that there is a greater prevalence of aortic arch plaques in patients with AS and that the presence of complex plaques is independently associated with cerebral infarction in these patients. Therefore, the identification of complex arch plaques using transesophageal echocardiography is important for risk stratification of cerebrovascular events in patients with severe AS.


American Journal of Cardiology | 2009

Persistent tricuspid regurgitation and its predictor in adults after percutaneous and isolated surgical closure of secundum atrial septal defect.

Manatomo Toyono; Richard A. Krasuski; Gosta Pettersson; Yoshiki Matsumura; Tetsuhiro Yamano; Takahiro Shiota

The fate of functional tricuspid regurgitation (TR) after closure of a secundum atrial septal defect (ASD) without any corrective tricuspid valve (TV) surgery remains unclear. We investigated this and the predictors of persistent TR after ASD closure. Thirty-two consecutive patients with moderate or severe TR before ASD closure were examined. Of these, 23 underwent percutaneous ASD closure, and 9 underwent isolated surgical ASD closure. The left ventricular end-diastolic volume, left ventricular ejection fraction, right ventricular end-diastolic area, right ventricular fractional area change, right ventricular spherical index, right atrial area, TV annular diameter, TV tethering height, pulmonary artery systolic pressure, and pulmonary/systemic blood flow ratio were determined by echocardiography before and early after ASD closure. The color Doppler maximal jet area was used to assess the severity of TR. After ASD closure, the jet area decreased for all patients (p = 0.009); however, 16 patients (50%) had persistent TR. Multivariate analysis revealed that only pulmonary artery systolic pressure before ASD closure was related to the TR jet area after ASD closure (p = 0.003). A pulmonary artery systolic pressure of >60 mm Hg predicted persistent TR with 100% sensitivity and 63% specificity. In conclusion, functional TR was ameliorated after percutaneous and isolated surgical ASD closure, although persistent TR was common. The presence of pulmonary hypertension before ASD closure predicted persistent TR; therefore, corrective TV surgery should be considered at ASD closure in adult patients with moderate or severe TR and concomitant pulmonary hypertension.


Journal of The American Society of Echocardiography | 2008

Diagnostic Value of Left Ventricular Outflow Area in Patients with Hypertrophic Cardiomyopathy: A Real-Time Three-Dimensional Echocardiographic Study

Shota Fukuda; Harry M. Lever; William J. Stewart; Hung Tran; Jong Min Song; Mi Seong Shin; Neil L. Greenberg; Nozomi Wada; Yoshiki Matsumura; Manatomo Toyono; Nicholas G. Smedira; James D. Thomas; Takahiro Shiota

BACKGROUND Earlier studies demonstrated the ability of real-time 3-dimensional (3D) echocardiography (3DE) to measure left ventricular outflow tract (LVOT) area (A(LVOT)) in patients with hypertrophic cardiomyopathy (HCM). However, its clinical value is unknown. OBJECTIVE We sought to investigate the feasibility and accuracy of real-time 3DE-derived A(LVOT) to diagnose significant LVOT obstruction in a large number of patients with HCM. METHODS A total of 162 patients with HCM had 3DE by using a volumetric system. The smallest A(LVOT) during systole was determined by moving a 2-dimensional plane in 3D space. The pressure gradient across LVOT was assessed by continuous wave Doppler method. Provocation was performed in patients without significant LVOT obstruction (pressure gradient across LVOT < 50 mm Hg) at rest. RESULTS Twenty (12%) patients with poor image quality of 3DE were excluded; 16 (28%) patients with a volumetric system, but only 4 (4%) patients with commercial equipment (P < .001). In the remaining 142 patients, A(LVOT) inversely correlated with pressure gradient across LVOT both at rest (r = 0.82, P < .001) and after provocation (r = 0.60, P < .001). The value of A(LVOT) less than 0.85 cm(2) and less than 2.0 cm(2) predicted resting and provokable LVOT obstruction with sensitivity of 87% and 81%, and specificity of 77% and 90%, respectively. CONCLUSIONS Real-time 3DE measurement of A(LVOT) was successful in diagnosing and quantifying LVOT obstruction at rest and after provocation in a large number of patients with HCM.


Archive | 2002

CASE REPORT: Asymptomatic Chronic Intestinal Ischemia Caused by Idiopathic Phlebosclerosis of Mesenteric Vein

Nobuhide Oshitani; Yoshiki Matsumura; Mizuki Kono; Akihiro Tamori; Kazuhide Higuchi; Takayuki Matsumoto; Shuichi Seki; Tetsuo Arakawa

Phlebosclerosis of the mesenteric vein is a rare condition causing chronic intestinal ischemia, it has only been reported in Japan. A 56-year-old man with liver cirrhosis and hepatic tumor presented with phlebosclerosis of mesenteric vein without any abdominal symptoms. He was admitted for examination of suspected hepatic tumor. Abdominal plain x-ray films and computed tomography revealed calcification of the mesenteric vein. Barium enema revealed narrowing and thumbprinting from the cecum to transverse colon. On colonoscopic examination, blue-black vessels were visible in the terminal ileum, and hyperemic nodular mucosa with small irregular ulcers surrounded by dark purple mucosa was found from the cecum to transverse colon. The etiology of mesenteric vein phlebosclerosis is unknown, although a physical mechanism rather than inflammatory changes appear to be involved in this rare and usually progressive condition of chronic intestinal ischemia.

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Takeshi Hozumi

Wakayama Medical University

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Takahiro Shiota

Cedars-Sinai Medical Center

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