Publications (224)721.15 Total impact
-
Article: Thrombus Aspiration Therapy and Coronary Thrombus Components in Patients with Acute ST-Elevation Myocardial Infarction.
[show abstract] [hide abstract]
ABSTRACT: Inflammation and oxidative stress play key roles in atherosclerotic plaque instability, and plaque rupture/erosion and subsequent thrombus formation constitute the principal mechanisms of total vessel occlusion and acute ST-elevation myocardial infarction (STEMI). Plaque disruption triggers the formation of initial platelet aggregates that grow in association with an increase in fibrin formation, leading to persistent coronary flow obstruction and blood coagulation. The fibrin network may trap large numbers of erythrocytes and inflammatory cells to form an erythrocyte-rich thrombus. In fact, previous clinical studies have shown that not only platelet-rich white thrombi, but also erythrocyte-rich red thrombi can be visualized using angioscopy in patients with acute coronary syndrome. Recently, the development of thrombus aspiration and distal protection devices has significantly improved the clinical outcomes of percutaneous intervention in STEMI patients and has enabled the evaluation of antemortem coronary artery thrombi. This is important because previous autopsy studies were unable to differentiate coronary thrombi responsible for myocardial ischemia from postmortem clots. Using frozen samples of aspirated thrombi and specific monoclonal antibodies, we investigated the cellular components of thrombi (platelets, erythrocytes, fibrin and inflammatory cells, such as myeloperoxidase-positive cells) and pathologically evaluated the relationships between erythrocyte-rich thrombi and inflammation, oxidative stress and clinical outcomes in STEMI patients. Therefore, this review article focuses on the efficacy of thrombus aspiration therapy and the components of aspirated intracoronary thrombi in STEMI patients and presents the results of recent studies regarding the relationship between the composition of aspirated intracoronary thrombi and clinical outcomes.Journal of atherosclerosis and thrombosis 04/2013; · 2.69 Impact Factor -
Article: Positive association between plasma levels of oxidized low-density lipoprotein and myeloperoxidase after hemodialysis in patients with diabetic end-stage renal disease.
[show abstract] [hide abstract]
ABSTRACT: End-stage renal disease (ESRD) patients undergoing hemodialysis (HD) have a high prevalence of cardiovascular events. Low-density lipoprotein (LDL) in dialysis patients has been shown to be susceptible to in vitro peroxidation; therefore, oxidized-LDL (ox-LDL) could be generated in these patients. Moreover, myeloperoxidase (MPO) released from activated neutrophils may play a role in the induction of LDL oxidation. The purpose of this study was to investigate the relationship between plasma ox-LDL levels, plasma MPO levels, and serum high-sensitivity C-reactive protein (hs-CRP) levels during initial HD in patients with diabetic ESRD. Patients (n = 28) had serial venous blood samples drawn before and after HD at the initial, second, and third sessions. Plasma ox-LDL levels were measured using a specific monoclonal antibody (DLH3), and plasma MPO levels were measured using an enzyme-linked immunosorbent assay kit. Plasma ox-LDL levels and MPO levels after a single HD session increased significantly (ox-LDL, P < 0.005; MPO, P < 0.0001) compared with levels before that HD session. However, the increase was transient since the levels returned to pre-HD session levels. Additionally, plasma MPO levels showed a positive correlation with plasma ox-LDL levels during HD (R = 0.62, P = 0.0029). No significant change was observed in serum hs-CRP levels before and after each HD session. This study demonstrates that plasma MPO levels are directly associated with plasma ox-LDL levels in diabetic ESRD patients during initial HD. These findings suggest a pivotal role for MPO and ox-LDL in the progression and acceleration of atherosclerosis in patients undergoing HD.Hemodialysis International 04/2013; · 1.54 Impact Factor -
Article: Simultaneous assessment of endothelial function and morphology in the brachial artery using a new semiautomatic ultrasound system.
[show abstract] [hide abstract]
ABSTRACT: The accuracy of measurements of the intima-media thickness (IMT) and flow-mediated dilatation (FMD) of the brachial artery made using a new semiautomated ultrasound system and the relationships among those parameters and the Framingham Risk Score (FRS) as a predictor of coronary heart disease (CHD) are unknown. We enrolled 70 subjects, including 47 patients with cardiovascular risk factors and 23 normal healthy volunteers. IMT and FMD were simultaneously measured using a new semiautomated ultrasound system, and the measurements were compared with those obtained manually as a reference standard (study 1). In addition, we enrolled 200 consecutive patients with risk factors but no CHD to examine the relationships among IMT, FMD and the FRS. The optimal cutoff values of FMD and IMT were determined in 200 patients without CHD, and the subjects were classified into four groups. The 10-year Framingham risks for each group were compared (study 2). FMD and IMT measurements made using the new semiautomated ultrasound system showed a good correlation with the measurements determined manually (study 1). Furthermore, FMD and IMT showed a significant correlation with the FRS. The 10-year Framingham risk was markedly higher in group D (FMD <5.5% and IMT >0.3 mm; 19.0±11.3%; study 2). In conclusion, the measurements made using a new semiautomated ultrasound system provided reliable and simultaneous evaluations of IMT and FMD. The combination of IMT and FMD measurements of the brachial artery may be beneficial for risk stratification of patients with cardiovascular risk factors but no CHD.Hypertension Research advance online publication, 18 April 2013; doi:10.1038/hr.2013.35.Hypertension Research 04/2013; · 2.58 Impact Factor -
Article: A Novel and Simple Method Using Pocket-Sized Echocardiography to Screen for Aortic Stenosis.
[show abstract] [hide abstract]
ABSTRACT: BACKGROUND: Pocket-sized echocardiography may serve as an initial tool to screen for aortic stenosis (AS). The purpose of this study was to evaluate the usefulness of a novel and simple method using pocket-sized echocardiography to screen for AS. METHODS: Subjects (n = 130) with systolic ejection murmur or known AS were studied. After physical examination, each aortic cusp's opening was visually scored using pocket-sized echocardiography as follows: 0 = not restricted, 1 = restricted, or 2 = severely restricted. The sum of the scores was defined as the visual AS score. On the basis of high-end echocardiography, an aortic valve area index <0.60 cm(2)/m(2) and an aortic valve area index of 0.60 to 0.85 cm(2)/m(2) were considered to indicate severe and moderate AS, respectively. RESULTS: For diagnosing severe AS (n = 27), a visual AS score ≥4 had sensitivity of 85% and specificity of 89%. For diagnosing moderate to severe AS (n = 57), a visual AS score ≥3 had sensitivity of 84% and specificity of 90%. The areas under the receiver operating characteristic curves for diagnosing severe and moderate to severe AS with a visual AS score (0.946 and 0.936, respectively) were slightly larger than those for a skilled physical examination (0.917 and 0.898, respectively) (P = NS for both) but were significantly larger than for an aortic valve calcification score also obtained using pocket-sized echocardiography (areas under the curve, 0.816 [P = .0015] and 0.827 [P = .0001], respectively). CONCLUSIONS: A novel and simple method using pocket-sized echocardiography is useful for rapid grading of AS in subjects with systolic ejection murmur.Journal of the American Society of Echocardiography: official publication of the American Society of Echocardiography 04/2013; · 2.98 Impact Factor -
Article: Impact of Concomitant Coronary Artery Disease on Atherosclerotic Plaques in the Aortic Arch in Patients With Severe Aortic Stenosis.
[show abstract] [hide abstract]
ABSTRACT: BACKGROUND: Coronary artery disease (CAD) often occurs concurrently in patients with severe aortic stenosis (AS). However, the influence of concomitant CAD on the presence of atherosclerotic complex plaques in the aortic arch, which is associated with increased stroke risk, has not been fully assessed in patients with severe AS. HYPOTHESIS: We hypothesized that concomitant CAD would be associated with the presence of complex arch plaques in patients with severe AS. METHODS: The study population consisted of 154 patients with severe AS who had undergone transesophageal echocardiography (TEE) and coronary angiography (71 male; mean age, 72 ± 8 years; mean aortic valve area, 0.67 ± 0.15 cm(2) ). Aortic arch plaques were assessed using TEE, and complex arch plaques were defined as large plaques (≥4 mm), ulcerated plaques, or mobile plaques. RESULTS: The prevalence of aortic arch plaques (87% vs 70%; P = 0.03) and complex arch plaques (48% vs 20%; P < 0.001) was significantly greater in AS patients with CAD than in those without CAD. After adjustment for traditional atherosclerotic risk factors, we found that concomitant CAD was independently associated with the presence of complex arch plaques (odds ratio: 2.86, 95% confidence interval: 1.23-6.68, P = 0.01). CONCLUSIONS: In patients with severe AS, concomitant CAD is associated with severe atherosclerotic burden in the aortic arch. This observation suggests that AS patients with concomitant CAD are at a higher risk for stroke, and that careful evaluation of complex arch plaques by TEE is needed for the risk stratification of stroke in these patients.Clinical Cardiology 04/2013; · 2.15 Impact Factor -
Article: Changes in serum cholesterol levels determine future risk of cardiovascular events in patients with acute coronary syndrome in the Japanese Coronary Artery Disease (JCAD) Study.
[show abstract] [hide abstract]
ABSTRACT: BACKGROUND: Although increased attention is given to assess absolute values of serum cholesterol profiles as optimal markers for preventing future cardiovascular (CV) events, changes in cholesterol profiles also have the potential to be associated with CV disease outcome in Japanese patients with acute coronary syndrome (ACS). METHODS: From the database of the Japanese Coronary Artery Disease (JCAD) study, 2664 patients with ACS who had serial measurements of serum cholesterol profile parameters were enrolled. These patients were followed-up for a mean period of 2.7 years. The endpoint was all CV events. Baseline clinical characteristics of patients with and without CV events were adjusted by the propensity score matching analysis. RESULTS: None of the serum absolute cholesterol profiles at baseline and 6 months later was associated with CV events, except for baseline serum total cholesterol level. However, large improvements in cholesterol profiles correlated with better CV disease outcome. CONCLUSIONS: This subanalysis of JCAD demonstrated the importance of serial assessment of serum cholesterol profiles for secondary prevention of CV events in Japanese patients with ACS. Changes in serum cholesterol profiles, rather than their absolute values, correlated with future CV events.Journal of Cardiology 03/2013; · 1.28 Impact Factor -
Article: Relationship of Thrombus Characteristics to the Incidence of Angiographically Visible Distal Embolization in Patients With ST-Segment Elevation Myocardial Infarction Treated With Thrombus Aspiration.
[show abstract] [hide abstract]
ABSTRACT: OBJECTIVES: This study sought to investigate the association between pathological characteristics of aspirated intracoronary thrombi and the incidence of angiographically visible distal embolization (AVDE) during primary percutaneous coronary intervention (p-PCI) in patients with ST-segment elevation myocardial infarction (STEMI) treated with thrombus aspiration. BACKGROUND: AVDE of atherosclerotic and thrombotic material has been shown to impair myocardial perfusion and contribute to poor clinical outcome in patients with STEMI. Recent studies have shown that thrombus composition and size are associated with the incidence of AVDE. METHODS: Aspirated thrombi from 164 STEMI patients within 12 h of symptom onset were investigated immunohistochemically using antibodies against platelets, erythrocytes, and inflammatory cells. RESULTS: The angiographic results showed that AVDE during p-PCI occurred in 22 (13.4%) patients. Pathological analysis revealed that thrombi from patients with AVDE had a greater erythrocyte-positive area (60 ± 15% vs. 43 ± 21%, p < 0.0005) and more myeloperoxidase-positive cells (943 ± 324 vs. 592 ± 419 cells/mm(2), p < 0.0005) than those from patients without AVDE. Thrombus size, quantified as the thrombus surface area, was positively correlated with the erythrocyte component (r = 0.362, p < 0.0001). Moreover, multivariate logistic analysis demonstrated that erythrocyte-positive area in the thrombi, glucose levels on admission, larger vessel diameter (≥3.5 mm), and pre-balloon dilation were independent predictors of the incidence of AVDE. CONCLUSIONS: This study demonstrated that the erythrocyte-rich component of aspirated thrombi may be associated with the incidence of AVDE during p-PCI in patients with STEMI.03/2013; · 1.07 Impact Factor -
Article: Napkin-Ring Sign on Coronary CT Angiography for the Prediction of Acute Coronary Syndrome.
[show abstract] [hide abstract]
ABSTRACT: OBJECTIVES: The aim of this study was to determine the predictive value of the napkin-ring sign on coronary computed tomography angiography (CTA) for future acute coronary syndrome (ACS) events in patients with coronary artery disease. BACKGROUND: Recent studies have reported a close association between the napkin-ring sign on coronary CTA and thin-cap fibroatheroma. METHODS: The subjects of this prospective study were 895 consecutive patients who underwent coronary CTA examination and were followed for >1 year. The primary endpoint was an ACS event (cardiac death, nonfatal myocardial infarction, or unstable angina pectoris). The coronary CTA analysis included the presence of obstructive plaque, positive remodeling (PR), low-attenuation plaque (LAP), and the napkin-ring sign. The napkin-ring sign was defined by the following criteria: 1) the presence of a ring of high attenuation around certain coronary artery plaques; and 2) attenuation of the ring presenting higher than those of the adjacent plaque and no greater than 130 Hounsfield units. RESULTS: Of the 12,727 segments, 1,174 plaques were observed, including plaques with PR in 130 segments (1.0%), LAP in 107 segments (0.8%), and napkin-ring signs in 45 segments (0.4%). Thirty-six of the 45 plaques with napkin-ring signs (80%) overlapped with those showing either PR or LAP. During the follow-up period (2.3 ± 0.8 years), 24 patients (2.6%) experienced ACS events, and plaques developed in 41% with a napkin-ring sign. Segment-based Cox proportional hazards models analysis showed that PR (p < 0.001), LAP (p = 0.007), and the napkin-ring sign (p < 0.0001) were independent predictive factors for future ACS events. Kaplan-Meier analysis demonstrated that plaques with napkin-ring signs showed a higher risk of ACS events compared with those without a napkin-ring sign. CONCLUSIONS: The present study demonstrated for the first time that the napkin-ring sign demonstrated on coronary CTA was strongly associated with future ACS events, independent of other high-risk coronary CTA features. Detection of the napkin-ring sign could help identify coronary artery disease patients at high risk of future ACS events.JACC. Cardiovascular imaging 03/2013; · 14.29 Impact Factor -
Article: Culprit lesion remodelling and long-term prognosis in patients with acute coronary syndrome: an intravascular ultrasound study.
[show abstract] [hide abstract]
ABSTRACT: AIMS: Positive arterial remodelling is recognized as one of the morphological characteristics of the vulnerable plaque. Limited data are available on a long-term outcome of acute coronary syndrome (ACS) patients with culprit lesion positive arterial remodelling (PR). The aim of this study was to investigate the long-term impact of culprit lesion PR in patients with ACS. METHODS AND RESULTS: In 134 patients with ACS, intravascular ultrasound (IVUS) was performed to assess target lesion remodelling before percutaneous coronary intervention. PR was defined as the ratio of the external elastic membrane cross-sectional area at the target lesion to that of at the proximal reference of >1.05, and intermediate or negative remodelling (IR/NR) was defined as that of ≤1.05. Major adverse cardiac event (MACE) was defined as a composite of death, ACS, and target lesion revascularization. During the follow-up (median 5.8 years), MACE-free survival was significantly lower in the PR group than that in the IR/NR group (log-rank, P = 0.005). Survival and ACS-free survival were also significantly lower in the PR group than that in the IR/NR group (log-rank, both P = 0.04). By multivariable Cox regression analysis, PR (hazard ratio = 2.4, P = 0.02) and diabetes (hazard ratio = 1.9, P = 0.03) were independent predictors of MACE. CONCLUSION: Culprit lesion PR was associated with a poor long-term prognosis in patients with ACS. PR may be a marker of vulnerable patients.European heart journal cardiovascular Imaging. 11/2012; -
Article: Impact of Lesion Length on Functional Significance in Intermediate Coronary Lesions.
[show abstract] [hide abstract]
ABSTRACT: BACKGROUND: Myocardial fractional flow reserve (FFR) is useful in the evaluation of coronary lesion ischemia. However, the impact of lesion length on FFR has not been adequately assessed. HYPOTHESIS: We hypothesized that lesion length would influence functional significance in intermediate coronary lesions. METHODS: FFR measurements were assessed in 136 patients (163 lesions) with stable angina who had >40% stenotic coronary lesion by quantitative coronary angiography (QCA). One hundred sixty-three lesions were classified as intermediate (40%-70% stenosis; n=107; group I) or significant (≥70%; n=56; group S) by QCA. We assessed the relationships between lesion length, coronary stenosis, and FFR in these 163 lesions. RESULTS: Regression analysis revealed an inverse correlation between the percentage of diameter stenosis (%DS) and FFR in group S (r = -0.83, P < 0.0001). In group I, no significant correlation was found between %DS and FFR (r = -0.06, P = 0.55), whereas lesion length was significantly inversely correlated with FFR (r = -0.79, P < 0.0001). Receiver operating characteristic curve analysis demonstrated that the best cutoff value for predicting an FFR value <0.80 was a lesion length >16.1 mm in group I (sensitivity, 86%; specificity, 94%). CONCLUSIONS: These study findings suggest that lesion length has a physiologically significant impact on intermediate-grade coronary lesions. Clin. Cardiol. 2011 DOI: 10.1002/clc.22076 The authors have no funding, financial relationships, or conflicts of interest to disclose.Clinical Cardiology 11/2012; · 2.15 Impact Factor -
Article: Aortic Atherosclerotic Plaque and Long-Term Prognosis in Patients With Atrial Fibrillation.
[show abstract] [hide abstract]
ABSTRACT: Background: Both left atrial spontaneous echo contrast (LASEC) and aortic atherosclerotic plaque (AoP) ≥4.0mm in thickness are predictors of cardiovascular events after stroke. The aim of this study was to investigate impact of AoP ≥4.0mm or LASEC on cardiovascular events in patients with atrial fibrillation (AF). Methods and Results: One hundred and eight consecutive patients with AF were enrolled and studied. Patients were grouped according to the presence or absence of AoP ≥4.0mm in the proximal aortic arch on transesophageal echocardiography (TEE). Cardiovascular events included death, myocardial infarction, ischemic stroke, systemic embolism and congestive heart failure. During a follow-up period (median, 3.9 years), cardiovascular event-free survival rate was significantly lower in patients with AoP ≥4.0mm than in patients without AoP ≥4.0mm (log-rank, P=0.01). In contrast, patients with LASEC showed a trend toward lower cardiovascular event-free survival than those without LASEC (log-rank, P=0.10). Univariate TEE predictors of cardiovascular events were AoP ≥4.0mm, LASEC and left atrial appendage flow velocity. On multivariate Cox regression analysis, AoP ≥4.0mm was the only TEE predictor of cardiovascular events during follow-up (P=0.02, hazard ratio, 2.6; 95% confidence interval: 1.1-6.0). Conclusions: In the present unselected patients with AF, AoP predicted long-term cardiovascular events.Circulation Journal 10/2012; · 3.77 Impact Factor -
Article: Absence of coronary calcification with normal endothelial function.
Circulation Journal 10/2012; 76(11):2544-5. · 3.77 Impact Factor -
Article: Effects of intravenous atrial natriuretic peptide and nitroglycerin on coronary vasodilation and flow velocity determined using 3 T magnetic resonance imaging in patients with nonischemic heart failure.
[show abstract] [hide abstract]
ABSTRACT: Although atrial natriuretic peptide (ANP) is widely used in patients with congestive heart failure (CHF), little is known about its effect on epicardial coronary arteries. Magnetic resonance imaging (MRI) enables precise measurement of coronary vasodilation and flow velocity. In this study, we examined the changes in epicardial coronary artery size and flow velocity in response to intravenous infusion of ANP or nitroglycerin (NTG) by using 3 T MRI in patients with CHF. The study cohort contained a total of 14 subjects: 8 patients with CHF and 6 healthy volunteers as controls, randomly divided into two groups: the ANP group (0.03 μg/kg/min) and the NTG group (0.3 μg/kg/min). Cross-sectional MR angiography and phase-contrast flow velocity of the right coronary artery in the same in-plane slice were obtained at the baseline, during drug infusion, and at two subsequent time points after stopping drug infusion. A significant increase was observed in the coronary cross-sectional area at 15 min after drug infusion in both groups compared with that at baseline; however, a late peak was observed at 15 min after stopping infusion in the ANP group. No significant differences were detected in the flow velocity in both groups. Furthermore, although NTG increased the heart rate, this change was not found in the ANP group. Coronary vasodilation and flow velocity can be measured simultaneously using 3 T MRI. Using this method, we showed that the effects of ANP on the coronary artery vasodilation and flow velocity were not inferior to those of NTG, with no significant alteration in heart rate.Heart and Vessels 09/2012; · 2.05 Impact Factor -
Article: Tolvaptan Improves Left Ventricular Dysfunction after Myocardial Infarction in Rats.
[show abstract] [hide abstract]
ABSTRACT: BACKGROUND: -Arginine vasopressin (AVP), which promotes the reabsorption of renal water is increased in chronic heart failure. Here, we compared the effects of tolvaptan, a newly developed non-peptide V(2) receptor antagonist, with those of furosemide, a loop diuretic, and a combination of these 2 agents in rats with left ventricular (LV) dysfunction after myocardial infarction (MI). METHODS AND RESULTS: -After 10 week of MI induction, rats were separated them into the following 6 groups adjusted to the infarct size: a vehicle group, a group treated with 15 mg·kg(-1)·day(-1) of furosemide; 2 groups treated with 3 or 10 mg·kg(-1)·day(-1) of tolvaptan, and 2 groups treated with 15 mg·kg(-1)·day(-1) of furosemide plus 3 or 10 mg(-)·kg(-1)·day(-1) tolvaptan. Each treatment agent was administered for 4 weeks, and all groups had similar blood pressure levels and infarct size. The tolvaptan-treated groups were found to have lower levels of LV end-diastolic and systolic cardiac volumes than the vehicle group. Furthermore, the improvement in the ejection fraction in the tolvaptan-treated groups was significantly greater than those in the vehicle group. ED-1 immunostaining and Sirius red staining revealed that tolvaptan significantly repressed MI-induced macrophage infiltration and interstitial fibrosis in the left ventricle, respectively. Tolvaptan attenuated the MI-induced mRNA expressions of atrial and brain natriuretic peptides, monocyte chemotactic protein-1, transforming growth factor-β1, AVP V(1a) receptor, and endothelin-1 in the marginal infarct region. CONCLUSIONS: -Tolvaptan may improve cardiac dysfunction after MI, which is partially mediated by the suppression of V(1a) receptor, neurohumoral activation and inflammation.Circulation Heart Failure 09/2012; · 6.29 Impact Factor -
Article: Peri-Atrial Epicardial Adipose Tissue Is Associated With New-Onset Nonvalvular Atrial Fibrillation.
[show abstract] [hide abstract]
ABSTRACT: Background: Atrial fibrillation (AF) is associated with considerable morbidity and mortality in patients with coronary artery disease (CAD). Epicardial adipose tissue (EAT) is recognized as an important inflammatory tissue that may exert deleterious effects on the adjacent left atrial (LA) wall. Multidetector computed tomography (MDCT) can accurately assess EAT's volume and distribution. This study used MDCT to investigate the effect of peri-atrial EAT on new-onset nonvalvular AF. Methods and Results: The study group consisted of 279 patients (176 men; age, 65±10 years) with no history of AF who underwent MDCT examination for evaluation of CAD. EAT was automatically identified on the basis of threshold attenuation values of -30 to -250 Hounsfield units. EAT volume was calculated as the sum of EAT area and subsequently divided into peri-atrial and peri-ventricular EAT. During follow-up of 3.3±1.0 years, AF occurred in 17 (6.1%) patients. Cox proportional hazards regression analysis indicated that male sex, and the LA and peri-atrial EAT volumes (P=0.03, P<0.001, and P<0.001, respectively) were independent predictors for future AF. The sensitivity and specificity for the prediction of AF using a peri-atrial EAT volume index of ≥27ml/m(2) were 88% and 92%, respectively. Conclusions: This is the first study demonstrating that peri-atrial EAT volume estimated by MDCT excellently predicted the development of new-onset AF in patients with CAD, independent of LA enlargement.Circulation Journal 08/2012; · 3.77 Impact Factor -
Article: [Drug-induced myocarditis and cardiomyopathy].
Nippon rinsho. Japanese journal of clinical medicine 08/2012; 70 Suppl 6:589-92. -
Article: Direct measurement of multiple vena contracta areas for assessing the severity of mitral regurgitation using 3D TEE.
[show abstract] [hide abstract]
ABSTRACT: The aim of this study was to determine whether direct measurement of multiple-jet vena contracta (VC) areas by real-time 3-dimensional (3D) transesophageal echocardiography is an accurate method for measuring the severity of mitral regurgitation (MR) in patients with multiple MR jets. Because of the conflicting requirements of Doppler and imaging physics, measuring VC using 2-dimensional (2D) echocardiography is a difficult procedure for assessing MR severity. A real-time 3D echocardiographic measurement of the VC area has been validated in a single jet of MR, but the applicability of this method for multiple jets is unknown. Two-dimensional and 3D transesophageal echocardiography was performed in 60 patients with multiple functional MR jets. MR severity was assessed quantitatively using the effective regurgitant orifice area derived from 3D left ventricular volume and thermodilution data (EROAstd). Manual tracings of multiple 3D VC areas in a cross-sectional plane through the VC were obtained, and the sum of the areas was compared using EROAstd. Similarly, 2D measurement of VC diameter was obtained from a 2D transesophageal echocardiographic view to optimize the largest legion size in each jet. All VC diameters were summed and compared with EROAstd. The correlation of the sum of the multiple 3D VC areas with EROAstd (r = 0.90, p < 0.01) was higher than that of the sum of the multiple 2D VC diameters (r = 0.56, p < 0.01), particularly with MR degrees greater than mild (r = 0.80, p < 0.01 vs. r = 0.05, p = 0.81) and in cases of 3 or more regurgitant jets (r = 0.91, p < 0.01 vs. r = 0.46, p = 0.05). Direct measurement of multiple VC areas using 3D transesophageal echocardiography allows for assessing MR severity in patients with multiple jets, particularly for MR degrees greater than mild and in cases of more than 2 jets, for which geometric assumptions may be challenging.JACC. Cardiovascular imaging 07/2012; 5(7):669-76. · 14.29 Impact Factor -
Article: Preliminary observations of passive exercise using whole body periodic acceleration on coronary microcirculation and glucose tolerance in patients with type 2 diabetes.
[show abstract] [hide abstract]
ABSTRACT: The whole body periodic acceleration (WBPA) system was recently developed as a passive exercise device by providing increased pulsatile shear stress for improvement of endothelial function. This study aimed to investigate the acute effects of WBPA on coronary microcirculation and glucose tolerance in patients with type 2 diabetes (T2D). The study subjects were 8 patients with T2D who underwent transthoracic Doppler echocardiography for the assessment of coronary flow reserve (CFR) before and immediately after a 45-min session of WBPA. The flow velocity in the distal portion of the left anterior descending coronary artery was measured at baseline and during adenosine infusion. The CFR represented the ratio of hyperemic to basal mean diastolic flow velocity. WBPA increased CFR from 2.3±0.3 to 2.6±0.4 (p=0.02). WBPA decreased serum insulin level from 26±19μIU/ml to 19±15μIU/ml (p=0.01) and increased total adiponectin from 11.6±7.3μg/ml to 12.5±8.0μg/ml (p=0.02) and high molecular weight adiponectin from 4.9±3.6μg/ml to 5.3±3.9μg/ml (p=0.03), whereas the serum glucose level was stable from 207±66mg/dl to 203±56mg/dl (p=0.8). This study demonstrates that a single session of WBPA treatment simultaneously improved coronary microcirculation and glucose tolerance in patients with T2D.Journal of Cardiology 06/2012; 60(4):283-7. · 1.28 Impact Factor -
Article: Detailed observation of arterial healing after stent implantation in swine arteries by using optical coherence tomography.
[show abstract] [hide abstract]
ABSTRACT: Histopathological examination is not suitable for sequential in vivo analysis of arterial healing after stenting because it can be performed only after the animals are killed. Optical coherence tomography (OCT) provides higher resolution than intravascular ultrasound (IVUS). The aim of this study was to compare arterial healing images after stenting on the basis of the findings of histopathological examination, IVUS, and OCT. We examined 12 vessels; 12 bare-metal stents were implanted in 6 miniature swine. Histopathological examination, IVUS, and OCT imaging were performed at 1 and 4 weeks after stenting. For quantitative analysis of IVUS and OCT images, we examined cross-sectional frames at 1-mm intervals. For neointimal coverage analysis, the neointimal coverage score was classified into 1 of the 4 categories. A fully covered strut was scored as 3, a partially covered strut was scored as 1 or 2, and an uncovered strut was scored as 0. In IVUS and OCT analyses, the average neointimal thickness increased between 1 and 4 weeks (p < 0.0001). OCT revealed higher scores at 1 and 4 weeks than IVUS did (at week 1, p < 0.0001; at week 4, p < 0.0001). OCT analysis evaluated the neointimal coverage similarly to histopathological examination. On assessment of arterial healing after stenting, we found that the results of the histological examination were more similar to those of the OCT analysis than to those of the IVUS. An OCT imaging device can be used to precisely and sequentially analyze the arterial healing process after stenting.Osaka city medical journal 06/2012; 58(1):1-11. -
Article: Aorto-renal bypass surgery normalized blood pressure without antihypertensive medications in a young female patient with renal artery occlusion.
[show abstract] [hide abstract]
ABSTRACT: We described a 19 year old female case with renovascular hypertension, whose blood pressure was high taking antihypertensive medications. The right renal artery was completely occluded at its ostium, and percutaneous transluminal renal angioplasty was unsuccessful. After aortorenal bypass surgery, blood pressure was normalized without administration of antihypertensive medication.Osaka city medical journal 06/2012; 58(1):45-9.
Top co-authors
Top Journals
Institutions
-
2013
-
Osaka City General Hospital
Ōsaka-shi, Osaka-fu, Japan
-
-
1999–2013
-
Osaka City University
- • Graduate School of Medicine
- • First Department of Internal Medicine
Ōsaka-shi, Osaka-fu, Japan
-
-
2004–2012
-
Columbia University
- Division of Cardiology
New York City, NY, USA
-
-
2011
-
Mazda Hospital, Fuchu
Fuchū, Hiroshima-ken, Japan
-
-
2010
-
University Hospital Medical Information Network
Tokyo, Tokyo-to, Japan
-
-
2009
-
University of Occupational and Environmental Health
- School of Medicine
Kitakyūshū, Fukuoka-ken, Japan
-
-
2007
-
Osaka General Medical Center
Ōsaka-shi, Osaka-fu, Japan
-
-
2005
-
Osaka University
- School of Pharmaceutical Sciences
Ōsaka-shi, Osaka-fu, Japan
-
