Masao Daimon

Juntendo University, Edo, Tōkyō, Japan

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Publications (67)283.46 Total impact

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    ABSTRACT: Elevated plasma B-type natriuretic peptide (BNP) is a predictor of outcome and helpful for risk stratification in aortic stenosis (AS). However, left ventricular (LV) diastolic dysfunction progresses with aging and may also influence plasma BNP levels in elderly patients. We hypothesized that plasma BNP levels may be influenced by age in severe AS, and that factors that affect the elevation of plasma BNP levels may be different between elderly and younger patients with AS. We performed echocardiography in 341 patients with severe AS [aortic valve area (AVA)<1.0cm(2)] and classified them into two groups by age (elderly ≥75 years old, n=201; younger patients <75 years old, n=140). We used multivariate linear regression analysis to assess the factors that determine plasma BNP levels in both groups. Age was found to be one of the independent determinants of plasma BNP levels in all patients (β=0.135, p=0.005). Although AVA was similar in the two groups, plasma BNP levels and E/e' were significantly higher in elderly than younger patients [133.0 (IQR, 73.3-329.7)pg/dl vs 92.8 (IQR, 40.6-171.8)pg/dl, p<0.01; 20±8 vs 16±6, p<0.01, respectively). In multivariate stepwise linear regression analysis, AVA index, LV ejection fraction, mass index, E/e', estimated systolic pulmonary artery pressure (eSPAS), and the presence of atrial fibrillation were independent determinants of plasma BNP levels in younger patients. In contrast, the independent determinants of plasma BNP levels in elderly patients were LV ejection fraction, mass index, E/e', eSPAS, the presence of atrial fibrillation, age, and hemoglobin levels, but not AVA index. There may be differences in the factors that influence plasma BNP levels between elderly and younger patients with severe AS. In elderly patients, plasma BNP levels may be influenced more by these factors than AS severity compared with younger patients.
    Journal of Cardiology 05/2014; · 2.30 Impact Factor
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    ABSTRACT: Background: The Trifecta valve (St Jude Medical) is a novel supra-annular aortic bioprosthesis designed to improve hemodynamic performance. We hypothesized that the Trifecta may offer better hemodynamic performance in Japanese patients, in whom the annulus is smaller, compared with Western populations. We compared the early results of hemodynamic performance between the Trifecta and the Magna (Edwards Lifescience) valves at our institution. Methods and Results: The Trifecta was implanted in 33 patients and the Magna was implanted in 41 patients who had aortic valve disease. Postoperative echocardiography was performed just before discharge, and the mean pressure gradient (MPG), effective orifice area (EOA) index and energy loss coefficient (ELCo) index were compared between the 2 groups. The average prosthesis size was similar between the 2 groups (21.1 vs. 21.3mm). The Trifecta group had a significantly lower MPG (P=0.001) and larger EOA index and ELCo index than the Magna group (P<0.001 for both). On multivariate linear regression analysis, use of the Trifecta was the strongest independent determinant of postoperative MPG, EOA and ELCo index. Conclusions: The Trifecta valve provides excellent early postoperative hemodynamic performance in Japanese patients. Patients with a small annulus size relative to body size may benefit more from the Trifecta in terms of postoperative hemodynamic performance.
    Circulation Journal 04/2014; · 3.58 Impact Factor
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    ABSTRACT: Background: Right atrial pressure (RAP) is commonly estimated using inferior vena cava (IVC) diameter and its respirophasic variations. Although a guideline has been provided for estimation of RAP due to variation in IVC dimensions based on studies in Western subjects, echocardiographic values in Asian subjects are unknown. Methods and Results: We studied 369 patients who underwent IVC ultrasound within 24h of right heart catheterization (RHC). The maximum and minimum IVC diameter during a respiratory cycle and the percent collapse after a sniff test were measured. These IVC parameters were compared with mean RAP measured on RHC. Receiver operating characteristic curves were generated for each IVC parameter to determine the optimal cut-off to detect RAP >10mmHg. The IVC maximum diameter cut-off for detecting RAP >10mmHg was 19mm (sensitivity, 75%; specificity, 78%) and the percent collapse cut-off was 30% (sensitivity, 75%; specificity, 83%). Both cut-offs were smaller than those previously reported in patients from Western countries. When the cut-off values from the existing guideline were applied to the present cohort, the sensitivity and specificity for normal RAP (0-5mmHg) were 38.6% and 74.2%, respectively, and 60.0% and 92.0% for elevated RAP (>10mmHg). Conclusions: The optimal IVC maximum diameter and percent collapse cut-offs to detect elevated RAP were smaller in Asian subjects than in a previously reported Western cohort.
    Circulation Journal 01/2014; · 3.58 Impact Factor
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    ABSTRACT: Background Elevated plasma B-type natriuretic peptide (BNP) is a predictor of outcome and helpful for risk stratification in aortic stenosis (AS). However, left ventricular (LV) diastolic dysfunction progresses with aging and may also influence plasma BNP levels in elderly patients. We hypothesized that plasma BNP levels may be influenced by age in severe AS, and that factors that affect the elevation of plasma BNP levels may be different between elderly and younger patients with AS. Methods We performed echocardiography in 341 patients with severe AS [aortic valve area (AVA) < 1.0 cm2] and classified them into two groups by age (elderly ≥75 years old, n = 201; younger patients <75 years old, n = 140). We used multivariate linear regression analysis to assess the factors that determine plasma BNP levels in both groups. Results Age was found to be one of the independent determinants of plasma BNP levels in all patients (β = 0.135, p = 0.005). Although AVA was similar in the two groups, plasma BNP levels and E/e′ were significantly higher in elderly than younger patients [133.0 (IQR, 73.3–329.7) pg/dl vs 92.8 (IQR, 40.6–171.8) pg/dl, p < 0.01; 20 ± 8 vs 16 ± 6, p < 0.01, respectively). In multivariate stepwise linear regression analysis, AVA index, LV ejection fraction, mass index, E/e′, estimated systolic pulmonary artery pressure (eSPAS), and the presence of atrial fibrillation were independent determinants of plasma BNP levels in younger patients. In contrast, the independent determinants of plasma BNP levels in elderly patients were LV ejection fraction, mass index, E/e′, eSPAS, the presence of atrial fibrillation, age, and hemoglobin levels, but not AVA index. Conclusions There may be differences in the factors that influence plasma BNP levels between elderly and younger patients with severe AS. In elderly patients, plasma BNP levels may be influenced more by these factors than AS severity compared with younger patients.
    Journal of Cardiology. 01/2014;
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    ABSTRACT: Background: The aim of this study was to determine whether global strain imaging diastolic index (SIDI) obtained using 2-D speckle tracking imaging (2DSI) could predict elevation in and rapid change of LV filling pressure. Methods and Results: Patients (n=126) underwent echocardiography and 2DSI during simultaneous cardiac catheterization. There were 60 patients in whom the same measurements were repeated 5min after i.v. glyceryl trinitrate. LV pre-atrial contraction pressure (pre-A) was measured as a surrogate of LV filling pressure. SIDI was defined as the change of LV longitudinal strain measured using 2DSI during the first one-third of diastole. Then, longitudinal global SIDI (L-global SIDI) was calculated as the mean SIDI of 18 LV segments. Mitral inflow and tissue Doppler imaging were also assessed. Among 126 patients, 93 patients had LV pre-A ≥15mmHg. L-global SIDI had a better correlation with LV pre-A (P<0.001, r=-0.56) than E/e' (P<0.01, r=0.35). On receiver operating characteristic curve analysis, L-global SIDI <0.48 was the optimum cut-off to predict LV pre-A ≥15mmHg (sensitivity, 82%; specificity, 68%). In addition, the ratio of L-global SIDI (after nitrate/before nitrate) was correlated with the ratio of LV pre-A (after nitrate/before nitrate; P=0.02, r=-0.34). Conclusions: A novel L-global SIDI derived from 2DSI may reflect elevated LV filling pressure and its rapid change better than conventional diastolic parameters.
    Circulation Journal 12/2013; · 3.58 Impact Factor
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    ABSTRACT: Large atheromatous aortic plaques (AAPs) are associated with stroke recurrence. Rosuvastatin is a potent lipid-lowering agent and suppresses carotid and coronary artery atherosclerosis. It is unclear whether rosuvastatin has anti-atherogenic effects against AAPs in stroke patients. We designed a clinical trial in stroke patients to analyze changes in AAPs after rosuvastatin treatment using repeated transesophageal echocardiography (TEE). This trial is a prospective randomized open label study. Inclusion criteria were patients were ischemic stroke with hypercholesterolemia and AAPs ≥4 mm in thickness. The patients are randomly assigned to either a group treated with 5 mg/day rosuvastatin or a control group. Primary endpoint is the changes in volume and composition of AAPs after 6 months using transesophageal echocardiography (TEE). Biochemical findings are analyzed. By using repeated TEE and binary image analysis, we will be able to compare the dynamic changes in plaque composition of AAPs before and after therapy in the two groups. The EPISTEME trial will provide information on the changes in plaque volume and composition achieved by improvement of lipid profiles with rosuvastatin therapy in stroke patients with aortic atherosclerosis. The results of the study may provide evidence for a therapeutic strategy for aortogenic brain embolism. This study is registered with UMIN-CTR (UMIN000010548).
    Cardiovascular Drugs and Therapy 09/2013; · 2.67 Impact Factor
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    ABSTRACT: Cardiovascular risk stratification of asymptomatic diabetic patients is important and remains a difficult clinical problem. Our aim was to test the hypothesis that coronary flow reserve (CFR) assessed by noninvasive transthoracic Doppler echocardiography predicts prognosis in those patients. From February 2002 to January 2005, we evaluated 135 consecutive asymptomatic patients (74 male; mean age, 63 +/- 9 years) with type 2 diabetes without a history of coronary artery disease. Adenosine triphosphate (0.14 mg/kg/min) stress Doppler echocardiography was performed to evaluate CFR of the left anterior descending artery. Patients with a CFR < 2.0 were also excluded based on the suspicion of significant coronary artery stenosis in the left anterior descending artery. There were 111 patients (60 male; mean age, 64 +/- 9 years) enrolled. During a median follow-up of 79 months, 20 events (5 deaths, 7 acute coronary syndromes, 8 coronary revascularizations) occurred. The optimal cut-off value of CFR to predict events was 2.5 (area under the receiver-operating characteristic curve = 0.65). Multivariate analysis showed that the independent prognostic indicators were male gender (p < 0.05) and a CFR < 2.5 (p < 0.01). Kaplan-Mayer analysis revealed that the event rate was significantly higher (log-lank, p < 0.01) in patients with CFR < 2.5 than in those with CFR >= 2.5. CFR obtained by transthoracic Doppler echocardiography provides independent prognostic information in asymptomatic patients with type 2 diabetes without overt coronary artery disease. Patients with CFR < 2.5 had a worse long-term outcome.
    Cardiovascular Diabetology 08/2013; 12(1):121. · 4.21 Impact Factor
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    ABSTRACT: The recognition of clinical symptoms is critical to a therapeutic strategy for aortic valve stenosis (AS). It was hypothesized that AS symptoms might have multiple causes; hence, a study was conducted to investigate the factors that separately influence the classic symptoms of dyspnea, angina and syncope in AS. The medical records of 170 consecutive patients with AS (> or = moderate grade) were reviewed. A multivariate logistic regression analysis was used to evaluate the hemodynamic and clinical factors that separately influence the development of three clinical symptoms: dyspnea (defined as NYHA class > or = 2), angina, and syncope. The most common symptom was dyspnea (47.1%), followed by angina (12.4%) and syncope (4.7%). The factors associated with dyspnea were a higher e' ratio (p = 0.04) and peak aortic valve velocity (p = 0.01). Only the severity of AS was associated with syncope. The presence of hypertension was associated with angina (p = 0.04). Moreover, coronary angiography was performed in 59 patients before aortic valve replacement and revealed coronary stenosis (> 50% diameter stenosis) in 11/16 patients (69%) that had angina. The presence of coronary stenosis was significantly associated with angina (p = 0.02). The development of dyspnea, angina or syncope was influenced by different factors in AS. Dyspnea and syncope were mainly associated with AS severity, and diastolic dysfunction also influenced dyspnea. In contrast, angina was mainly related to the presence of coronary stenosis rather than to AS severity. These factors should be considered when, selecting a therapeutic strategy for AS patients in the modern era.
    The Journal of heart valve disease 05/2013; 22(3):287-94. · 1.07 Impact Factor
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    ABSTRACT: Disaster victim identification (DVI) presents a number of physical and legal challenges, involving the degeneration of human remains and legal obstacles to forensic examinations. One non-invasive method for positive identification may be the use of a pacemaker programmer to detect and obtain data from pacemakers recovered from unidentified remains. To test the usefulness of this method, this investigation examined the efficiency and utility of 5 different pacemaker programmers in the positive identification of victims of the March 2011 tsunami in Japan at 8 disaster sites in May 2011. On scanning 148 sets of remains, data were successfully obtained from 1 implant in 1 set of remains, allowing for the rapid positive identification of the individual. Scanning pacemakers with pacemaker programmers can be a non-invasive method of positive identification that meets Japanese legal and institutional requirements, but this method is ineffective without a preceding whole-body X-ray scan.
    Forensic Science Medicine and Pathology 04/2013; · 2.44 Impact Factor
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    ABSTRACT: BACKGROUND: We hypothesized that clinical factors other than glycemic control may influence abnormal cardiac function in patients with type 2 diabetes mellitus (T2DM). We aimed to investigate the independent factors for abnormal cardiac function among clinical factors in T2DM. METHODS: We studied 148 asymptomatic patients with T2DM without overt heart disease. Echocardiographic findings were compared between diabetic patients and 68 age-matched healthy subjects. Early (E) and late (A) diastolic mitral flow velocity and early diastolic mitral annular velocity (e') were measured for assessing left ventricular (LV) diastolic function. We evaluated insulin resistance, non-esterified fatty acid, high-sensitive CRP, estimated glomerular filtration rate, waist/hip ratio, abdominal visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT) and other clinical characteristics in addition to glycemic control. VAT and SAT were quantified by computed tomography. RESULTS: In T2DM, E/A and e' were significantly lower, and E/e', left atrial volume and LV mass were significantly greater than in control subjects. In multivariate liner regression analysis, VAT was an independent determinant of left atrial volume (beta =0.203, p=0.011), E/A (beta =-0.208, p=0.002), e' (beta =-0.354, p<0.001) and E/e' (beta=0.220, p=0.003). Age was also an independent determinant, whereas fasting plasma glucose and hemoglobin A1c levels were not. In addition to systolic blood pressure, waist-hip ratio (beta=0.173, p=0.024) and VAT/SAT ratio (beta=0.162, p=0.049) were independent determinants of LV mass. CONCLUSION: Excessive visceral fat accompanied by adipocyte dysfunction may play a greater role than glycemic control in the development of diastolic dysfunction and LV hypertrophy in T2DM.
    Cardiovascular Diabetology 02/2013; 12(1):38. · 4.21 Impact Factor
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    ABSTRACT: Noninvasive detection of coronary artery stenosis usually requires a stress test in patients without left ventricular (LV) regional wall motion abnormalities (RWMA). In contrast, abnormal regional LV relaxation caused by ischemia may persist beyond recovery from transient ischemia. The aim of the present study was to determine whether segmental analysis of abnormal regional LV relaxation using the strain imaging diastolic index (SI-DI) at rest could predict coronary artery stenosis in the three major vessels in patients without LV dysfunction or RWMA. We performed 2D speckle tracking echocardiography and coronary angiography in 85 patients without RWMA with suspected coronary artery disease. Patients with LV dysfunction or acute coronary syndrome were excluded. Echocardiographic images of the LV were obtained in the apical 2-, 3-, and 4-chamber views and divided into 6 segments. In each segment, SI-DI derived from transverse strain imaging was determined. Forty-eight patients had significant coronary artery stenosis (≥ 70%). The optimal cutoff values of SI-DI were 60.5% in the mid anteroseptal segment for detecting left anterior descending artery stenosis (sensitivity, 83.3%; specificity, 81.1%), 60.5% in the basal anterolateral segment for detecting left circumflex artery stenosis (sensitivity, 80.9%; specificity, 90.3%), and 61.5% in the basal inferior segment for detecting right coronary artery stenosis (sensitivity, 74.1%; specificity, 77.8%). A segmental analysis of SI-DI at rest predicted coronary artery stenosis in the three major vessels in patients without RWMA. This noninvasive method may be useful for detecting coronary artery stenosis without a stress test.
    International Heart Journal 01/2013; 54(5):266-272. · 1.23 Impact Factor
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    ABSTRACT: We evaluated the effectiveness of a home telehealth service in hypertension control. Patients with hypertension were divided into two groups based on the frequency that they measured blood pressure (BP) at home: the regular group made >3 measurements per week and the irregular group made ≤ 20 measurements per month. Both groups were provided with home monitoring equipment (the Citizen Telemedical Care Service System, CTCS) which contained a computer and video communication device. A total of 160 participants were enrolled and 156 completed the 12-month study. There were 101 participants in the regular BP measurement group and 55 in the irregular group. There was a significant reduction in the average systolic BP from baseline after 6 months in the regular group (P < 0.001) and after 1 month in the irregular group (P < 0.001). There was no difference in average diastolic BP between the two groups. For both groups, the systolic BP control was good, especially for irregular group. The results suggest that patients who used CTCS tele-monitoring achieved better BP control than those who self-measured BP at home only.
    Journal of telemedicine and telecare 01/2013; 19(5):238-41. · 0.92 Impact Factor
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    ABSTRACT: BACKGROUND: The recently developed real-time 3-dimensional echocardiography (RT3DE) is a promising imaging method to quantify cardiac chamber volumes and their functions in clinical practice. However, normal reference values of RT3DE parameters have not been fully investigated in a large, healthy Japanese population. Methods and Results: This study consisted of 410 healthy subjects aged from 20 to 69 years who had a RT3DE at one of the 23 collaborating institutions. All subjects had no history of cardiac disease and no risk factors. The mean values in men and women were as follows: 50 ± 12 ml/m(2) and 46 ± 9 ml/m(2) for left ventricular (LV) end-diastolic volume index, 19 ± 5 ml/m(2) and 17 ± 4 ml/m(2) for end-systolic volume index, 61 ± 4% and 63 ± 4% for ejection fraction, 64 ± 1 2 g/m(2) and 56 ± 11 g/m(2) for mass index, 23 ± 6 ml/m(2) and 24 ± 6 ml/m(2) for left atrial (LA) maximum volume index, 10 ± 3 ml/m(2) and 10 ± 3 ml/m(2) for minimum volume index, and 58 ± 6% and 58 ± 6% for percent volume change. LV sizes decreased with age, whereas LV mass index did not change. LA sizes slightly increased with age. Conclusions: This multicenter investigation determined normal reference values for LV and LA sizes, and their functional parameters on RT3DE in a large, healthy Japanese population. The results of the present study support the use of RT3DE for the diagnosis and management of cardiovascular disease.
    Circulation Journal 02/2012; 76(5):1177-81. · 3.58 Impact Factor
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    ABSTRACT: The purpose of the present study was to investigate gender differences in age-related changes of left ventricular (LV) and right ventricular (RV) geometries and functions throughout the entire adult age range using the Japanese Normal Values for Echocardiographic Measurements Project (JAMP) study database. Seven hundred healthy volunteers (aged 20-79 years) underwent 2-dimensional and Doppler echocardiography. The subjects were stratified into 6 different age groups and then stratified by gender in each age group. LV diastolic function was assessed from pulsed wave Doppler measurements of mitral early (E) and late (A) inflow velocities and tissue Doppler measurements of mitral early (e') and late (a') annular velocities. LV volume decreased and LV mass increased with age to a similar extent in both men and women. Furthermore, for subjects <50 years, women had significantly greater E, E/A ratio and e' than men, but these parameters were similar between genders in subjects >50 years. In addition, there was a significant interaction between age and gender that affected the differences in E, e' and E/e' among the groups (P<0.03, P<0.01, and P<0.03, respectively; ANOVA). There were no gender differences in age-related changes in RV parameters. Gender differences were found in age-related changes in LV diastolic function in a healthy population. Gender differences should be considered for optimal diagnosis and management of cardiovascular disease.
    Circulation Journal 09/2011; 75(12):2840-6. · 3.58 Impact Factor
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    ABSTRACT: Global longitudinal strain (GLS) measured by two-dimensional speckle tracking imaging (2D-STI) has been shown to be useful for assessing subtle change in left ventricular function in severe aortic stenosis (AS) patients with preserved left ventricular ejection fraction (LVEF). However, there is little information about the relation between the progression of AS and changes in GLS. The aim of this study was to evaluate the relation between the severity of valve stenosis and GLS measured by 2D-STI in AS patients with normal LVEF. We studied 113 AS patients (age, 73.3 ± 8.8 years; male, 38%; aortic valve area (AVA), 1.0 ± 0.3 cm(2); mean pressure gradient (PG), 33.8 ± 22.1 mmHg) with normal LVEF (≥50%) but without overt coronary artery disease. Patients were stratified into three groups (mild, moderate and severe AS), and the clinical characteristics and echocardiographic findings were compared among the groups. Using dedicated software, we measured GLS in the apical four-chamber view. LVEF was not significantly different among the three groups. However GLS showed significant differences in GLS among the three groups (mild: 17.1 ± 3.0%, moderate: 16.4 ± 3.0% and severe: 14.5 ± 3.9%, ANOVA P = 0.003). GLS was significantly correlated with AVA, mean PG, LVEF, LV mass index and early diastolic mitral annular velocity (e'). In multiple stepwise regression analysis, mean PG, LVEF and hypertension were independently associated with GLS (R(2) = 0.247, P = 0.0001). Despite unchanged LVEF, GLS gradually decreased as severity of AS increases. GLS measured by 2D-STI might be useful to assess subtle changes in LV function in AS patients. 
    Echocardiography 05/2011; 28(7):703-8. · 1.26 Impact Factor
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    ABSTRACT: In patients with ischemic mitral regurgitation (IMR), we assessed dynamic changes in mitral annular geometry and motion during the cardiac cycle, and examined their association with the severity of IMR, using our computerized three-dimensional (3D) echo method. Real-time 3D echo was performed in 12 normal controls and 25 patients with IMR. The saddle-shaped annulus was reconstructed in every 3D volume/frame during a cardiac cycle. For each 3D volume/frame, we assessed the mitral annular area (MAA) and the annular contraction that was expressed as the percentage of the largest MAA accounted for by the change in MAA from largest to smallest calculated value. In IMR patients, the minimum MAA occurred in late-systole, while it occurred in early-systole in the controls. IMR patients had a larger minimum MAA (6.7 ± 1.3 vs. 3.6 ± 0.8 cm², P < 0.001) and reduced annular contraction (23.0 ± 6.5 vs. 42.6 ± 7.0%, P < 0.001) when compared to controls. Both minimum MAA and annular contraction had significant correlations with IMR severity (r = 0.67 and r = 0.78, P < 0.001 for both). The contraction of the dilated mitral annulus occurred in late-systole in patients with IMR. The alterations of annular geometry and motion may be associated with the development of IMR.
    Echocardiography 10/2010; 27(9):1069-77. · 1.26 Impact Factor
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    ABSTRACT: While mitral valve replacement is generally considered as the standard surgical treatment for rheumatic mitral stenosis (MS), mitral valve repair may be an alternative therapeutic option. Several techniques have been used to overcome the anatomic difficulties involved in the repair of a rheumatic mitral valve. In the present study, quantitative echocardiography was used to investigate the effects of mitral valve repair and the influence of surgical procedures on mitral valve geometry in patients with rheumatic MS. Mitral valve repair was successfully performed in seven patients with MS, by the same surgeon. Ring annuloplasty and slicing of the anterior mitral leaflet (AML) were performed in all patients. Concomitant surgical techniques included commissurotomy, decalcification, chordal resection, and division of the papillary muscles. The preoperative and postoperative echocardiographic findings in these patients were compared. The thickness of both the AML and posterior mitral leaflet (PML) (p = 0.01 for both), the opening angles of the AML (p = 0.02) and PML (p = 0.01), and the closing angle of the PML, the extent of calcification in the AML, and the pressure half-time (PHT) (p = 0.03 for all three parameters) were all significantly improved after mitral valve repair. In the present study, the transmitral peak velocity and mean pressure gradient were not significantly changed after mitral valve repair, whereas the PHT showed a marked improvement. Hence, the PHT may represent a suitable marker for evaluating the efficacy of mitral valve repair for MS.
    The Journal of heart valve disease 07/2010; 19(4):427-33. · 1.07 Impact Factor
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    ABSTRACT: BackgroundMitral valve repair is a feasible treatment option in patients with rheumatic mitral valve disease, but it is not always successful. Mitral valve replacement is generally the surgical treatment of choice in such patients. We aimed to examine whether the Wilkins score can predict the feasibility of surgical repair in such patients. MethodsMitral valve surgery was performed on 14 patients by the same surgeon (A.A.). Five patients underwent mitral valve repair (group I), and nine patients underwent mitral valve replacement (group II). The Wilkins scores were determined by assessing echocardiography findings. The selection of mitral valve repair or replacement was based on the intraoperative findings and the preferences of the same surgeon (A.A.). In group I, we performed chordal reconstruction, augmentation of the posterior leaflet, resection of chordae, decalcification of the commissure, commissurotomy, slicing of the anterior leaflet, division of the papillary muscle, and ring annuloplasty in various combinations. ResultsThere were no significant differences between the two groups with regard to any component of the preoperative Wilkins score. There was no significant difference in the pre- and postoperative scores in group I; however, the mitral valve orifice area was significantly improved after the operation (pre- and postoperative mean values: 1.3±0.3 and 2.0±0.4, P<0.05). ConclusionMitral valve repair is effective in treating rheumatic mitral stenosis. However, the Wilkins score may not be useful in predicting the feasibility of mitral repair. KeywordsMitral valve repair-Mitral stenosis-Wilkins score-Echocardiography-Valvular heart disease-Cardiac surgery
    Journal of Echocardiography 01/2010; 8(4):106-111.
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    ABSTRACT: Epidemiologic studies have reported that sleep deprivation is associated with cardiovascular events. However, it remains unknown how sleep deprivation affects the coronary circulation. We assessed the impact of sleep deprivation on the coronary circulation using coronary flow velocity reserve (CFVR) measurements with transthoracic Doppler echocardiography. We studied 26 healthy male volunteers. Each subject's CFVR was measured in the morning after sleep deprivation (less than 4 h) or normal sleep (more than 7 h) on different days. Sleep durations were 3.7 ± 0.9 h (sleep deprivation) and 7.1 ± 0.2 h (normal sleep). CFVR after sleep deprivation was significantly lower than that after normal sleep (3.3 ± 0.6 versus 4.2 ± 0.9, p<0.001). Short sleep duration attenuated CFVR compared with normal sleep duration. This finding suggests that sleep deprivation might serve as a trigger for cardiovascular events.
    International journal of cardiology 03/2009; 144(2):266-7. · 7.08 Impact Factor
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    ABSTRACT: Normal values for echocardiographic measurements and the relationship between these parameters and age in a large Japanese population are still unknown. A total of 700 healthy Japanese aged 20-79 years underwent 2-dimensional and Doppler echocardiography at collaborating institutions. The respective mean values obtained in men and women were as follows: septal wall thickness, 0.9+/-0.1 and 0.8+/-0.1 cm; posterior wall thickness, 0.9+/-0.1 and 0.8+/-0.1 cm; left ventricular (LV) diastolic diameter, 4.8+/-0.4 and 4.4+/-0.3 cm; LV systolic diameter, 3.0+/-0.4 and 2.8+/-0.3 cm; LV diastolic volume, 93+/-20 and 74+/-17 ml; LV systolic volume, 33+/-20 and 25+/-7 ml; LV ejection fraction, 64+/-5 and 66+/-5%; maximum left atrial (LA) volume, 42+/-14 and 38+/-12 ml. Aortic root diameter, LV wall thickness, and LV mass slightly increased with age, whereas indexed LA volume did not vary with age. Diastolic parameters assessed by mitral inflow and mitral annular velocities declined with age, as previously reported. Normal values of echocardiographic measurements in a large Japanese population are reported for the first time; several systolic and diastolic parameters varied with age. These results provide important reference values that should be useful in routine clinical practice as well as in clinical trials.
    Circulation Journal 10/2008; 72(11):1859-66. · 3.58 Impact Factor

Publication Stats

703 Citations
283.46 Total Impact Points

Institutions

  • 2008–2014
    • Juntendo University
      • • Department of Cardiology
      • • Department of Cardiovascular Surgery
      Edo, Tōkyō, Japan
  • 2005–2010
    • Cleveland Clinic
      Cleveland, Ohio, United States
  • 2002–2009
    • Chiba University
      • Graduate School of Medicine
      Chiba-shi, Chiba-ken, Japan
  • 2006–2008
    • Lerner Research Institute
      Cleveland, Ohio, United States
  • 2001–2002
    • Osaka City University
      • Graduate School of Medicine
      Ōsaka-shi, Osaka-fu, Japan