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Dive into the research topics where Kunitsugu Takasaki is active.

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Featured researches published by Kunitsugu Takasaki.


Journal of the American College of Cardiology | 2002

Repeated Sauna Treatment Improves Vascular Endothelial and Cardiac Function in Patients With Chronic Heart Failure

Takashi Kihara; Sadatoshi Biro; Masakazu Imamura; Shiro Yoshifuku; Kunitsugu Takasaki; Yoshiyuki Ikeda; Yutaka Otuji; Shinichi Minagoe; Yoshifumi Toyama; Chuwa Tei

OBJECTIVES The purpose of this study was to determine the mechanism by which 60 degrees C sauna treatment improves cardiac function in patients with chronic heart failure (CHF). BACKGROUND We have previously reported that repeated 60 degrees C sauna treatment improves hemodynamic data and clinical symptoms in patients with CHF. We hypothesized that the sauna restores endothelial function and then improves cardiac function. METHODS Twenty patients (62 plus minus 15 years) in New York Heart Association (NYHA) functional class II or III CHF were treated in a dry sauna at 60 degrees C for 15 min and then kept on bed rest with a blanket for 30 min, daily for two weeks. Ten patients with CHF, matched for age, gender and NYHA functional class, were placed on a bed in a temperature-controlled (24 degrees C) room for 45 min as the nontreated group. Using high-resolution ultrasound, we measured the diameter of the brachial artery at rest and during reactive hyperemia (percent flow-mediated dilation, %FMD: endothelium-dependent dilation), as well as after sublingual administration of nitroglycerin (%NTG: endothelium-independent dilation). Cardiac function was evaluated by measuring the concentrations of plasma brain natriuretic peptide (BNP). RESULTS Clinical symptoms were improved in 17 of 20 patients after two weeks of sauna therapy. The %FMD after two-week sauna treatment significantly increased from the baseline value, whereas the %NTG-induced dilation did not. Concentrations of BNP after the two-week sauna treatment decreased significantly. In addition, there was a significant correlation between the change in %FMD and the percent improvement in BNP concentrations in the sauna-treated group. In contrast, none of the variables changed at the two-week interval in the nontreated group. CONCLUSIONS Repeated sauna treatment improves vascular endothelial function, resulting in an improvement in cardiac function and clinical symptoms.


Circulation | 2006

Mechanism of Recurrent/Persistent Ischemic/Functional Mitral Regurgitation in the Chronic Phase After Surgical Annuloplasty Importance of Augmented Posterior Leaflet Tethering

Eiji Kuwahara; Yutaka Otsuji; Yoshifumi Iguro; Tetsuya Ueno; Fang Zhu; Naoko Mizukami; Kayoko Kubota; Kenichi Nakashiki; Toshinori Yuasa; Bo Yu; Takeshi Uemura; Kunitsugu Takasaki; Masaaki Miyata; Shuichi Hamasaki; Akira Kisanuki; Robert A. Levine; Ryuzo Sakata; Chuwa Tei

Background— Surgical annuloplasty can potentially hoist the posterior annulus anteriorly, exaggerate posterior leaflet (PML) tethering, and lead to recurrent ischemic/functional mitral regurgitation (MR). Characteristics of leaflet configurations in late postoperative MR were investigated. Methods and Results— In 30 patients with surgical annuloplasty for ischemic MR and 20 controls, the anterior leaflet (AML) and PML tethering angles relative to the line connecting annuli, posterior and apical displacement of the coaptation and the MR grade were measured by echocardiography before, early after, and late after surgery. Early after surgery, grade of MR and AML tethering generally decreased (P<0.01), whereas PML tethering significantly worsened (P<0.01). Nine of the 30 patients showed recurrent/persistent MR late after surgery. Compared with patients without late MR, those with the MR showed similar reduction in the annular area, significant re-increase in posterior displacement of the coaptation, and progressive worsening in PML tethering (P<0.05) late after surgery in comparison to the early phase. Both preoperative MR and late postoperative MR were significantly correlated with all tethering variables in univariate analysis. Although apical displacement of the coaptation was the primary determinant of preoperative MR (r2=0.60, P<0.0001), increased PML tethering was the primary determinant of late MR (r2=0.75, P<0.0001). Conclusions— Whereas both leaflets tethering is related to preoperative ischemic MR, both leaflets tethering but with predominant contribution from augmented and progressive PML tethering is related to recurrent/persistent ischemic/functional MR late after surgical annuloplasty.


Journal of the American College of Cardiology | 2001

Repeated thermal therapy improves impaired vascular endothelial function in patients with coronary risk factors

Masakazu Imamura; Sadatoshi Biro; Takashi Kihara; Shiro Yoshifuku; Kunitsugu Takasaki; Yutaka Otsuji; Shinichi Minagoe; Yoshifumi Toyama; Chuwa Tei

OBJECTIVES We sought to determine whether sauna therapy, a thermal vasodilation therapy, improves endothelial function in patients with coronary risk factors such as hypercholesterolemia, hypertension, diabetes mellitus and smoking. BACKGROUND Exposure to heat is widely used as a traditional therapy in many different cultures. We have recently found that repeated sauna therapy improves endothelial and cardiac function in patients with chronic heart failure. METHODS Twenty-five men with at least one coronary risk factor (risk group: 38 +/- 7 years) and 10 healthy men without coronary risk factors (control group: 35 +/- 8 years) were enrolled. Patients in the risk group were treated with a 60 degrees C far infrared-ray dry sauna bath for 15 min and then kept in a bed covered with blankets for 30 min once a day for two weeks. To assess endothelial function, brachial artery diameter was measured at rest, during reactive hyperemia (flow-mediated endothelium-dependent dilation [%FMD]), again at rest and after sublingual nitroglycerin administration (endothelium-independent vasodilation [%NTG]) using high-resolution ultrasound. RESULTS The %FMD was significantly impaired in the risk group compared with the control group (4.0 +/- 1.7% vs. 8.2 +/- 2.7%, p < 0.0001), while %NTG was similar (18.7 +/- 4.2% vs. 20.4 +/- 5.1%). Two weeks of sauna therapy significantly improved %FMD in the risk group (4.0 +/- 1.7% to 5.8 +/- 1.3%, p < 0.001). In contrast, %NTG did not change after two weeks of sauna therapy (18.7 +/- 4.2% to 18.1 +/- 4.1%). CONCLUSIONS Repeated sauna treatment improves impaired vascular endothelial function in the setting of coronary risk factors, suggesting a therapeutic role for sauna treatment in patients with risk factors for atherosclerosis.


American Journal of Cardiology | 2003

Pseudonormalized Doppler total ejection isovolume (Tei) index in patients with right ventricular acute myocardial infarction.

Shiro Yoshifuku; Yutaka Otsuji; Kunitsugu Takasaki; Keiko Yuge; Akira Kisanuki; Koichi Toyonaga; Souki Lee; Takashi Murayama; Hitoshi Nakashima; Toshiro Kumanohoso; Shinichi Minagoe; Chuwa Tei

The Doppler total ejection isovolume (Tei) index is useful for estimating global cardiac function. However, the relation between the right ventricular (RV) Tei index and RV infarction has not been investigated. The relation between the RV Tei index and severity of RV infarction was evaluated in 25 patients with inferior wall acute myocardial infarction (13 with and 12 without RV infarction). RV infarction was diagnosed when right atrial pressure was > or = 10 mm Hg or when right atrial pressure/pulmonary capillary wedge pressure was >0.8 by catheterization. The RV Tei index was significantly increased in patients with RV infarction compared with those without (0.53 +/- 0.15 vs 0.38 +/- 0.14, p <0.05). The RV Tei index in patients with severe RV infarction (right atrial pressure > or = 15 mm Hg) was significantly smaller compared with those with mild/moderate RV infarction (right atrial pressure <15 mm Hg) and showed no significant difference in patients with myocardial infarction but without RV infarction (0.44 +/- 0.09 vs 0.61 +/- 0.16 vs 0.38 +/- 0.14, severe RV infarction vs mild/moderate RV infarction vs no RV infarction, p <0.01). The RV Tei index is generally increased in patients with RV infarction; however, severe RV infarction can be manifested with limited or no increase in the Tei index (pseudonormalization).


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.


Echocardiography-a Journal of Cardiovascular Ultrasound and Allied Techniques | 2008

Preoperative and Postoperative Mitral Valve Prolapse and Regurgitation in Adult Patients with Secundum Atrial Septal Defects

Manatomo Toyono; Gosta Pettersson; Yoshiki Matsumura; Nozomi Wada; Shota Fukuda; Tetsuhiro Yamano; Kunitsugu Takasaki; Takahiro Shiota

Background: Little attention is given to development of mitral regurgitation (MR) in adults with atrial septal defect (ASD). The aim of the study was to determine the associated factors of MR in ASD adults before surgical repair and the fate of moderate to severe MR after surgery. Methods: We examined 71 consecutive patients with secundum ASD (47 ± 16 years) who underwent surgical repair. Clinical and echocardiographic variables including size of left and right heart systems and severity of MR and tricuspid regurgitation (TR) were investigated before and early after surgery. Results: Before ASD closure, 14 patients (20%) had moderate to severe MR and 25 patients (35%) showed mitral valve (MV) prolapse. The ASD patients with moderate to severe MR showed worse cardiovascular symptoms, increased occurrence of atrial fibrillation and MV prolapse, and greater left ventricular (LV) end‐diastolic volume, left atrial area, and TR severity than those with none to mild MR (all P < 0.05). Among preoperative variables, TR severity, left atrial area, LV end‐diastolic volume, and MV prolapse were associated with preoperative MR severity in all the patients (all P < 0.03). Isolated ASD closure (n=46) decreased MV prolapse (P=0.008). Preoperative moderate to severe MR decreased after ASD closure with and without MV surgery (n=9 and 5, respectively; both P < 0.05). Conclusions: Preoperative MR severity was associated with TR severity, dilated left heart chambers, and MV prolapse. MR decreased after ASD closure with and even without MV surgery.


Hypertension Research | 2010

Left ventricular global systolic dysfunction has a significant role in the development of diastolic heart failure in patients with systemic hypertension

Mihoko Kono; Akira Kisanuki; Nami Ueya; Kayoko Kubota; Eiji Kuwahara; Kunitsugu Takasaki; Toshinori Yuasa; Naoko Mizukami; Masaaki Miyata; Chuwa Tei

Regional left ventricular (LV) systolic dysfunction has been identified in diastolic heart failure (DHF). However, the relationship between regional or global LV systolic function and heart failure symptoms in DHF has not been evaluated in detail. The present study evaluates such relationships in patients with systemic hypertension (HT) and DHF. We assessed LV systolic and diastolic function in 220 consecutive patients with systemic HT and in 30 normal individuals (Control) using Doppler echocardiography. Patients with HT were assigned to groups with DHF, asymptomatic diastolic dysfunction (ADD) and no diastolic dysfunction (Simple HT). Ejection fraction in DHF was significantly decreased (63±8%) compared with the Control, Simple HT and ADD groups (67±5, 66±7 and 68±8%, respectively). Isovolumetric contraction time in DHF (70±30 msec) was significantly increased compared with those in the ADD, Simple HT and Control groups (31±17, 31±15 and 30±19 msec, respectively). Mitral annular systolic velocities were significantly decreased in the DHF and ADD groups (6.4±1.5 and 7.2±1.3 cm sec−1, respectively) compared with those in the Simple HT and Control groups (8.5±1.8 and 8.4±3.0 cm sec−1, respectively), and in the DHF group compared with the ADD group. LV global systolic dysfunction has a significant role in the development of heart failure symptoms associated with DHF in patients with systemic HT.


Journal of The American Society of Echocardiography | 2009

Different Determinants of Residual Tricuspid Regurgitation after Tricuspid Annuloplasty: Comparison of Atrial Septal Defect and Mitral Valve Prolapse

Manatomo Toyono; Shota Fukuda; A. Marc Gillinov; Gosta Pettersson; Yoshiki Matsumura; Nozomi Wada; Tetsuhiro Yamano; Kunitsugu Takasaki; Takahiro Shiota

We analyzed 20 patients with atrial septal defect (ASD) who underwent tricuspid valve (TV) annuloplasty and ASD closure, 21 patients with mitral valve prolapse (MVP) who underwent mitral valve (MV) and TV annuloplasty, and 20 healthy controls. Severity of tricuspid regurgitation (TR) was assessed by maximal TR jet area/RA area (%TR) using echocardiography before and early after surgery. Before surgery, 2 groups of patients showed significantly greater RA area, TV annulus diameter, RV systolic pressure, and %TR than controls. %TR was significantly decreased after surgery, whereas residual TR was shown in 19% of the MVP group and 25% of the ASD group. Preoperative TV tethering height and %TR were significantly associated with postoperative %TR in the MVP group, whereas preoperative RV fractional area change, RV spherical index, and RV systolic pressure were significantly associated with postoperative %TR in the ASD group. Risk stratification after TV annuloplasty should take the structural abnormality into consideration.


Journal of the American College of Cardiology | 2005

Papillary muscle dysfunction attenuates ischemic mitral regurgitation in patients with localized basal inferior left ventricular remodeling

Takeshi Uemura; Yutaka Otsuji; Toshiro Kumanohoso; Kunitsugu Takasaki; Toshinori Yuasa; Woo-Shik Kim; Akira Kisanuki; Shinichi Minagoe; Robert A. Levine; Chuwa Tei

OBJECTIVES The purpose of this research was to test whether papillary muscle (PM) dysfunction attenuates ischemic mitral regurgitation (MR) in patients with left ventricular (LV) remodeling of a similar location and extent. BACKGROUND Papillary muscle dysfunction could attenuate tethering and MR because of PM elongation. However, variability in the associated LV remodeling, which exaggerates tethering, can influence the relationship between PM dysfunction and MR. METHODS In 40 patients with a previous inferior myocardial infarction but without other lesions, the LV volume, sphericity, PM tethering distance, PM longitudinal systolic strain, and MR fraction were quantified by echocardiography. The patients were divided into two groups: group 1 with significant basal inferoposterior LV bulging but without advanced LV bulging involving other territories, therefore with a similar location and extent of LV remodeling, and group 2 without significant LV bulging. RESULTS The medial PM tethering distance was significantly correlated with the %MR fraction (r2 = 0.64, p < 0.01), and multiple regression analysis identified an increase in the tethering distance as the only independent determinant of the MR fraction in all subjects and also in group 1. The PM longitudinal systolic strain had no significant relationships with MR fraction in all subjects with variable degrees of LV remodeling, but it had a significant inverse correlation with the MR fraction (r2 = 0.33, p < 0.01) in group 1 with LV remodeling of a similar location and extent, indicating that PM dysfunction is associated with less MR. CONCLUSIONS Papillary muscle dysfunction, reducing its longitudinal contraction to induce leaflet tethering, attenuates ischemic MR in patients with basal inferior LV remodeling.


Journal of Atherosclerosis and Thrombosis | 2016

Validity of a Novel Method for Estimation of Low-Density Lipoprotein Cholesterol Levels in Diabetic Patients

Hideto Chaen; Shigesumi Kinchiku; Masaaki Miyata; Shoko Kajiya; Hitoshi Uenomachi; Toshinori Yuasa; Kunitsugu Takasaki; Mitsuru Ohishi

Aim: Low-density lipoprotein cholesterol (LDL-C) is routinely estimated using the Friedewald equation [LDL-C(F)]. A novel method for LDL-C [LDL-C(M)] estimation recently proposed by Martin et al. was reported to be more accurate than the Friedewald formula in subjects in the United States. The validity of LDL-C(M) in different races and patients with diabetes mellitus (DM) has not been elucidated. The purpose of this study was to validate the LDL-C(M) estimates in Japanese population with type 2 DM by comparing with LDL-C(F) and directly measured LDL-C [LDL-C(D)]. Methods: Both LDL-C(M) and LDL-C(F) levels were compared against LDL-C(D) measured by selective solubilization method in 1,828 Japanese patients with type 2 DM. Results: On linear regression analysis, LDL-C(M) showed a stronger correlation than that shown by LDL-C(F) (R = 0.979 vs. R = 0.953, respectively) with LDL-C(D). We further analyzed the effect of serum triglyceride (TG) concentrations on the accuracy of LDL-C(F) and LDL-C(M). Although LDL-C levels showed a positive correlation with TG levels, the LDL-C(F) levels tended to show a greater divergence from LDL-C(D) levels than that shown by LDL-C(M) with changes in TG levels. Conclusion: We for the first time demonstrated a more useful measurement of LDL-C levels estimated by Martins method than that estimated by the Friedewald equation in Japanese patients with DM.

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Yutaka Otsuji

University of Occupational and Environmental Health Japan

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