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Yoshio Yasumura

Publications and source records attributed to Yoshio Yasumura.

At least 19 recordsLinked to original sources
PubMed2006

[Inotropic agents].

We now know pharmacological negative inotropic agent, i. e. beta-blocker, increase cardiac contractility when given chronically to patients with chronic heart failure. In contrast, positive inotropic agents have consistently been shown to increase mortality when given chronically. The routine use of inotropes in either acute or the chronic setting is not supported by the available data. However, some appropriate uses of inotropes are as temporary use of refractory acutely decompensated heart failure, or as a bridge to definitive treatment, or palliative measure in a subset of patients with end-stage heart failure.

Cardiotonic Agents↗
PubMed2005

Increased gene expression of collagen Types I and III is inhibited by beta-receptor blockade in patients with dilated cardiomyopathy.

AIMS: To elucidate the cellular mechanisms of cardioprotection of beta-blockers in patients with heart failure, we investigated the effects of beta-blockers on collagen synthesis in patients with dilated cardiomyopathy (DCM). METHODS AND RESULTS: We examined the gene expression before and 4 months after the administration of a beta-blocker in 17 DCM patients. The messenger ribonucleic acid expression of collagen Types I and III (Col I and III) and transforming growth factor-beta(1) (TGF-beta(1)) of right ventricular tissues obtained by the endomyocardial biopsy were assessed by quantitative reverse transcriptase-polymerase chain reaction. Cardiac sympathetic nerve activity was assessed by the washout rate (WR) of (123)I-metaiodobenzylguanidine from the heart. Left ventricular ejection fraction (21 +/- 7 vs. 35 +/- 9%) and WR (53+/-14 vs. 42 +/- 13%) improved significantly. Before the beta-blocker treatment, the expressions of both Col I (r = 0.560, P = 0.041) and Col III (r = 0.630, P = 0.008) genes were correlated with WR. The expression levels of both Col I (1.08 +/- 0.72 vs. 0.65 +/- 0.26, P = 0.024) and Col III (2.06 +/- 1.81 vs. 1.05 +/- 0.74, P = 0.018) were reduced by a beta-blocker. Changes in TGF-beta(1) correlated with those in WR (r = 0.606, P = 0.002). CONCLUSION: beta-Blockers are considered to inhibit the expression of collagen-related genes in DCM, which seems to be mediated by TGF-beta(1).

Adrenergic beta-Antagonists↗
PubMed2005

Rationale and design of a randomized trial to assess the effects of beta-blocker in diastolic heart failure; Japanese Diastolic Heart Failure Study (J-DHF).

BACKGROUND: Heart failure consists of two phenotypes: systolic heart failure and diastolic heart failure (DHF). A growing body of evidence demonstrated benefits of beta-blocker, angiotensin-converting enzyme inhibitor, and angiotensin II receptor blocker in systolic heart failure; however, evidence leading to therapeutic strategy of DHF is lacking. METHODS AND RESULTS: The Japanese Diastolic Heart Failure Study (J-DHF) is a multicenter, prospective, randomized trial designed to assess effects of beta-blocker in patients with DHF. A total of 800 patients (400 patients in each group) will be enrolled. The primary outcome is a composite of cardiovascular death and unplanned admission to hospital for congestive heart failure. Other outcomes include all-cause mortality, worsening of the symptoms of heart failure, or a need for modification of the treatment for heart failure. Serial assessment of echocardiographic and neurohumoral parameters and cost analysis of the treatment regimen will be conducted. The follow-up period is a minimum of 2 years. CONCLUSION: This study will provide important evidences for the treatment of DHF.

Adrenergic beta-Antagonists↗
PubMed2005

Assessment of quality of life with 5 different scales in patients participating in comprehensive cardiac rehabilitation after acute myocardial infarction.

BACKGROUND: Measures assessing quality of life (QOL) in patients participating in comprehensive cardiac rehabilitation (CCR) have not been established in Japan. METHODS AND RESULTS: To compare different types of QOL scales and to determine the impact of CCR on QOL in Japanese cardiac patients, 5 different types of questionnaires were assessed in 44 patients participating in CCR after acute myocardial infarction (AMI). After 3-month CCR, peak oxygen uptake (PVO2, p<0.01), Sickness Impact Profile (SIP) total score (p<0.05) and physical function-related QOL scores (Specific Activity Scale (SAS), p<0.01; SIP physical score, p<0.01) significantly improved, whereas psychosocial/mental aspect-related QOL scores (Ministry of Health and Welfare (MHW)-QOL score, SIP psychosocial score, State-Trait Anxiety Inventory, Self-rating Depression Scale) did not change on the average. However, patients with low PVO2 (<21.7 ml.min-1.kg-1) showed significant improvements in all scores after CCR, whereas patients with preserved exercise capacity showed improvements only in physical function-related scores (SAS and physical SIP). Furthermore, patients with anxiety and depression showed significant improvements in these respective measures after CCR. CONCLUSION: In patients with AMI, physical function-related QOL scores improve after a 3-month CCR program, but psychosocial/mental aspect-related QOL scores improve only in those with impaired exercise tolerance or anxiety/depression. Thus, changes in QOL after CCR depend on type of QOL scale used and the baseline status of the patient. In addition, in Japanese cardiac patients MHW-QOL mainly reflects psychosocial/mental aspect-related QOL, as well as overall QOL.

Activities of Daily Living↗
PubMed2004

Effects of ghrelin administration on left ventricular function, exercise capacity, and muscle wasting in patients with chronic heart failure.

BACKGROUND: Ghrelin is a novel growth hormone-releasing peptide that also induces vasodilation, inhibits sympathetic nerve activity, and stimulates feeding through growth hormone-independent mechanisms. We investigated the effects of ghrelin on left ventricular (LV) function, exercise capacity, and muscle wasting in patients with chronic heart failure (CHF). METHODS AND RESULTS: Human synthetic ghrelin (2 microg/kg twice a day) was intravenously administered to 10 patients with CHF for 3 weeks. Echocardiography, cardiopulmonary exercise testing, dual x-ray absorptiometry, and blood sampling were performed before and after ghrelin therapy. A single administration of ghrelin elicited a marked increase in serum GH (25-fold). Three-week administration of ghrelin resulted in a significant decrease in plasma norepinephrine (1132+/-188 to 655+/-134 pg/mL; P<0.001). Ghrelin increased LV ejection fraction (27+/-2% to 31+/-2%; P<0.05) in association with an increase in LV mass and a decrease in LV end-systolic volume. Treatment with ghrelin increased peak workload and peak oxygen consumption during exercise. Ghrelin improved muscle wasting, as indicated by increases in muscle strength and lean body mass. These parameters remained unchanged in 8 patients with CHF who did not receive ghrelin therapy. CONCLUSIONS: These preliminary results suggest that repeated administration of ghrelin improves LV function, exercise capacity, and muscle wasting in patients with CHF.

Aged↗
PubMed2004

The role of a common TNNT2 polymorphism in cardiac hypertrophy.

We found a five-basepair insertion/deletion polymorphism in intron 3 of TNNT2, one of the genes responsible for hypertrophic cardiomyopathy. These five bases may be part of an intronic polypyrimidine tract sequence that may affect splicing. The purpose of the study was to examine the association of the polymorphism with cardiac hypertrophy. The study population consisted of 151 subjects with prominent concentric left ventricular hypertrophy, and 987 healthy subjects recruited from medical checkups (control population). The deletion/deletion genotype tended to be associated with a larger left ventricular mass/height ratio in the HCM population ( p<0.0001). Multiple regression analyses indicated that the left ventricular mass/height ratio was determined ( p<0.0001, R=0.738) by the TNNT2 genotype. Moreover, the frequency of the deletion allele was significantly higher in the hypertrophy population than in the control population ( p<0.0001). In vitro expression study revealed the deletion allele significantly affected the mRNA expression pattern by skipping exon 4 during splicing. In conclusion, TNNT2 deletion allele could be associated with a predisposition to prominent left ventricular hypertrophy.

Aged↗
PubMed2004

A novel data mining approach to the identification of effective drugs or combinations for targeted endpoints--application to chronic heart failure as a new form of evidence-based medicine.

BACKGROUND: Data mining is a technique for discovering useful information hidden in a database, which has recently been used by the chemical, financial, pharmaceutical, and insurance industries. It may enable us to detect the interesting and hidden data on useful drugs especially in the field of cardiovascular disease. METHODS AND RESULTS: We evaluated the current treatments for chronic heart failure (CHF) in our institute using a decision tree method of data mining and compared the results with those of large-scale clinical trials. We enrolled 1,100 patients with CHF (NYHA classes II-IV and EF < 40%) who were hospitalized at the National Cardiovascular Center during the past 31 months. Drugs prescribed at discharge were extracted from the clinical database. Both echocardiograms and plasma BNP level at 6-12 months after discharge were determined prospectively. It was found that beta-blockers, angiotensin converting enzyme inhibitors, and angiotensin II receptor antagonists independently improve both the plasma BNP level and %fractional shortening (FS), while oral inotropic agents increased the plasma BNP level and decreased %FS. These findings agree with evidence accumulated from several large-scale trials. Interestingly, statins, histamine receptor blockers, and alpha-glucosidase inhibitors also attenuated the severity of CHF, suggesting the possibility of new treatment of CHF. CONCLUSION: Clinical data mining using Japanese CHF patients yielded almost identical data to the results of large-scale trials, and also suggested novel and unexpected candidates for CHF therapy. Further validation of the data mining approved in the cardiovascular field is warranted.

Chronic Disease↗
PubMed2004

Consequence of atrial fibrillation and the risk of embolism after percutaneous mitral commissurotomy: the necessity of the maze procedure.

BACKGROUND: We sought to investigate the incidence and risk of embolism after percutaneous balloon mitral commissurotomy (PMC) and delineated the necessity of the maze procedure in patients with atrial fibrillation (AF). METHODS: Clinical records of 326 patients, who underwent PMC between April 1988 and March 2003, and 162 patients, who underwent mitral valve surgery (MVS) combined with the maze procedure (MVS/maze) in the same period, were reviewed. We examined the consequence of cardiac rhythm and the incidence and risk of embolism after PMC. Next our current criteria for indication of the maze procedure, which included duration of AF less than 10 years, voltage of f wave on electrocardiography greater than 0.1 mV, cardiothoracic ratio less than 70%, and left atrial dimension less than 70 mm, were applied to all patients. These criteria were satisfied by 190 patients of PMC (PMC group) and 114 patients of MVS/maze (MVS/maze group) and the early and late results of the two groups were compared. RESULTS: Thirty-eight patients suffered from embolic complications after PMC. Of these 33 patients experienced AF before intervention. The actuarial embolism-free rate at 10 years was 81.9% in patients with AF before PMC and 92.9% in patients with sinus rhythm before PMC (p = 0.01). Univariate predictors of embolism after PMC included previous embolic history (p = 0.01), AF (p = 0.01), pressure gradient (p = 0.01), age (p = 0.03), and mitral valve area (p = 0.04). Multivariate analysis identified AF as the independent predictor of embolism in the late follow-up period (p = 0.03). In a comparative study of the selected patients the actuarial AF-free rates after MVS/maze were 89.9% at 1 year and 85.7% at 5 years and were significantly higher than those of 17.3% at 1 year and 4.2% at 5 years after PMC (p < 0.0001). The actuarial embolism-free rate in the MVS/maze group was 98.0% at 5 years and was significantly higher than that of 84.8% at 5 years and 82.4% at 10 years in the PMC group (p = 0.01). CONCLUSIONS: PMC alone is not sufficient with regard to sinus rhythm recovery and prevention of embolism. Surgical treatment concomitant with the maze procedure may be beneficial for patients with AF.

Atrial Fibrillation↗
PubMed2004

Rationale for the use of combination angiotensin-converting enzyme inhibitor and angiotensin II receptor blocker therapy in heart failure.

BACKGROUND: The present multicenter study investigated whether the combination of angiotensin-converting enzyme inhibitor (ACEI) and angiotensin II receptor blocker (ARB) is more beneficial for preventing left ventricular remodeling and suppressing neurohumoral factors than either ACEI or ARB alone. METHODS AND RESULTS: One hundred and six patients with mild-to-moderate congestive heart failure treated in 26 Japanese institutes were randomly assigned to the combination therapy or monotherapy. Changes in physical activity (New York Heart Association functional classes, Specific Activity Scale (SAS)), concentrations of neurohumoral factors (plasma renin activity, angiotensin II, aldosterone, and brain natriuretic peptide (BNP)), and cardiac function for 6 months were compared between the 2 groups. It was found that the combination therapy, which was administered at doses standard in Japan, increased the SAS score (4.5 +/- 1.5 to 4.9 +/- 1.5, p<0.05) and decreased the plasma BNP concentration (183 +/- 163 to 135 +/- 118 pg/ml, p<0.05). In contrast, there were no changes in SAS score (4.5 +/- 1.4 to 4.6 +/- 1.4, NS) or BNP concentration (156 +/- 157 to 151 +/- 185 pg/ml, NS) in the patients receiving monotherapy. CONCLUSIONS: The results of the study demonstrate that the combination therapy, even at the standard doses for Japan, improves physical activity and plasma BNP concentration more than the monotherapy. A larger study is required to assess the effects of the combination therapy on major clinical outcomes.

Adrenergic beta-Antagonists↗
PubMed2004

Anomalous right coronary artery originating from the distal left circumflex artery: single coronary artery with choronic atrial fibrillation.

This report describes a patient with a single coronary artery in whom the right coronary artery originated from the distal left circumflex artery. Single coronary artery is a rare congenital anomaly of the coronary circulation which is often associated with other congenital cardiac malformations. This anomaly is thought to be clinically significant especially in patients with atrial fibrillation, although no other associated cardiac anomaly was detected.

Angina Pectoris↗
PubMed2004

Gated myocardial SPECT to predict response to beta-blocker therapy in patients with idiopathic dilated cardiomyopathy.

UNLABELLED: Because of the difficulty of predicting the response of patients with idiopathic dilated cardiomyopathy (IDC) to beta-blocker therapy, this study was performed to evaluate whether gated myocardial SPECT (gated SPECT) could be useful for predicting that response. METHODS: We performed gated SPECT with (99m)Tc-sestamibi on 38 patients with IDC before treatment with a beta-blocker and standard medication. Perfusion abnormalities, left ventricular (LV) function, and spheric distortion were assessed by a quantitative software program. RESULTS: We classified patients into 2 groups according to improvement in LV function after 4 mo of therapy. The groups consisted of 16 poor responders whose LV ejection fraction (LVEF) increased less than 10% and 22 good responders whose LVEF increased by 10% or more. The patient characteristics before therapy, including LV volume and LVEF, did not significantly differ between the 2 groups, but the size of the myocardial perfusion defect and spheric distortion were significantly greater in poor responders than in good responders. CONCLUSION: Gated SPECT, by allowing simultaneous assessment of perfusion, function and geometry, might be useful for predicting the response of patients with IDC to beta-blocker therapy.

Adrenergic beta-Antagonists↗
PubMed2003

Patients with large myocardial infarction gain a greater improvement in exercise capacity after exercise training than those with small to medium infarction.

BACKGROUND: It remains unclear whether patients with large-size myocardial infarction (MI) achieve the same benefit from exercise training as do those with small- to medium-size MI. HYPOTHESIS: This study was designed to determine the magnitude and mechanisms underlying improvement in exercise capacity in patients with large-size MI after cardiac rehabilitation. METHODS: In all, 296 patients who participated in a cardiac rehabilitation program after acute MI were divided into two groups according to the peak serum creatine phosphokinase (CPK) level: the group with large infarction (Group 1) (> or = 5000 U/l peak CPK, 64 patients) and the group with less extensive infarction (Group 2) (< 5000 U/I, 232 patients). Exercise capacity was assessed before and after a 3-month cardiac rehabilitation program that included exercise training. RESULTS: Before exercise training, both the peak work rate (p < 0.05) and peak oxygen uptake (VO2) (p < 0.01) were significantly lower in Group 1 than in Group 2. After exercise training, the changes in peak work rate and peak VO2 were significantly greater in Group 1 than in Group 2 (both p < 0.01). The infarction size measured by the peak CPK level correlated significantly with both the baseline exercise capacity and its improvement after exercise training, although these correlations were insignificant in a multivariate analysis. In the multivariate analysis, the improvement in exercise capacity is determined by age and baseline exercise capacity, which is determined by the duration of inactivity, minute ventilation (VE)/VCO2 slope and left ventricular end-diastolic pressure. CONCLUSIONS: Compared with patients with small- to medium-size myocardial infarction, patients with large infarction gain a greater improvement in exercise capacity after exercise training due to reversal of physical deconditioning and improvement in congestive heart failure.

Adaptation, Physiological↗
PubMed2003

Löffler's endocarditis associated with unusual ECG change mimicking posterior myocardial infarction.

A73-year-old man with a history of bronchial asthma and atrial fibrillation was admitted to our hospital because of dyspnea and back pain. Blood analysis revealed a marked increase in total blood cell and eosinophil counts. The creatine kinase and creatine kinase-MB increased slightly. The ECG demonstrated significant ST-segment depression that mimicked acute posterior myocardial infarction. Emergent coronary angiography showed no stenotic lesions. The histological findings in endomyocardial biopsy showed thickened endocardium associated with significant eosinophilic infiltration, which was compatible with Löffler's endocarditis. After the administration of prednisolone, the patient's general condition, eosinophilia, ECG abnormalities, and histological findings were improved dramatically. The endomyocardial biopsy in the acute phase was helpful for diagnosis and therapeutic decision-making.

Aged↗
PubMed2003

Exercise training without ventricular remodeling in patients with moderate to severe left ventricular dysfunction early after acute myocardial infarction.

BACKGROUND: The purpose of this study was to determine whether or not patients with moderate to severe left ventricular (LV) dysfunction benefit from exercise training starting early after acute myocardial infarction (AMI) without deteriorating LV remodeling. METHODS: We investigated changes in exercise capacity and LV end-diastolic dimension (LVDd by two-dimensional echocardiography) before and after exercise training in 126 patients after AMI. Patients were divided into three groups according to LV ejection fraction (EF) at the beginning of exercise training: 74 patients with LVEF>/=45% (Group H), 35 patients with 35%</=LVEF<45% (Group M), and 17 patients with LVEF<35% (Group L). Exercise training was prescribed at a moderate intensity (50-60% of heart rate reserve or Karvonen's equation). Exercise capacity was assessed by peak work rate (WR) and peak oxygen uptake (VO(2)) by upright cardiopulmonary exercise test before and after 3 months of exercise training. LVDd was measured before and at 27+/-10 months of follow-up period. RESULTS: At the baseline, Group L had a significantly lower LVEF (H 55+/-7 vs. M 40+/-3 vs. L 30+/-3%, P<0.05), significantly greater LVDd (49+/-6 vs. 52+/-7 vs. 56+/-6 mm, P<0.05), and a higher incidence of anterior infarction (P<0.01) compared with Groups H and M, whereas there were no difference in age, sex, coronary risk factors, the incidence of multivessel disease, prior myocardial infarction, peak WR or peak VO(2) among the three groups. After 3 months of exercise training, exercise capacity increased significantly (all P<0.01) in all groups. The magnitudes of the increases in peak VO(2) (%Deltapeak VO(2): 18+/-20 vs. 15+/-19 vs. 18+/-17%, NS) and peak WR (%Deltapeak WR: 17+/-17 vs. 16+/-14 vs. 15+/-13%, NS) were similar among the three groups. In addition, there was no significant correlation between %Deltapeak VO(2) and baseline LVEF. No increase in LVDd was observed in any group at follow-up (H 48+/-5 to 49+/-4 mm vs. M 53+/-8 to 52+/-8 mm vs. L 57+/-5 to 57+/-7 mm, NS in each group). CONCLUSION: Patients with moderate to severe LV dysfunction benefit from exercise training starting early after AMI without deteriorating LV remodeling, with a similar magnitude of improvement in exercise capacity to that in patients with mild LV dysfunction.

Adult↗
PubMed2003

Changes in myocardial gene expression associated with beta-blocker therapy in patients with chronic heart failure.

BACKGROUND: The left ventricular functional recovery by beta-blocker therapy is now attributed to time-dependent biologic effects on cardiomyocytes. METHODS AND RESULTS: To elucidate the cellular mechanism of these biologic effects, we treated 9 patients with dilated cardiomyopathy for 4 months with beta-blockers and examined the gene expressions linked to an improvement of left ventricular ejection fraction (EF). Gene expressions of the biopsied right ventricular endomyocardium were assessed by real-time reverse transcription-polymerase chain reaction. A decrease in beta-myosin heavy chain (1.23+/-0.49 versus 0.86+/-0.45, P<.05) was observed 4 months after the administration of beta-blockers. The expression levels of both sarcoplasmic reticulum Ca(2+) ATPase (SERCA) (0.80+/-0.28 versus 1.39+/-0.44, P<.01) and phospholamban (PLB) (0.49+/-0.08 versus 0.88+/-0.34, P<.05) increased, whereas the expression levels of Na(+)-Ca(2+) exchanger (NCX), beta-adrenoreceptor kinase 1, and ryanodine receptor 2 were unchanged. The SERCA/NCX ratio (0.68+/-0.14 versus 0.96+/-0.33, P<.05) also increased. The increase in SERCA mRNA expression correlated with the degree of changes in EF (%deltaEF) (r=0.679, P<.05), and none of changes in these genes expression correlated with changes in the plasma brain natriuretic peptide concentration. CONCLUSIONS: The functional recovery resulting from beta-blockers may be associated with the restoration of the unfavorable gene expression that controls Ca(2+) handlings in the failing heart.

Adrenergic beta-Antagonists↗
PubMed2003

Restrictive cardiomyopathy with right-sided dominant heart failure after sinus conversion from atrial fibrillation: case report.

A 44-year-old woman with restrictive cardiomyopathy showed right-sided dominant heart failure after conversion to sinus rhythm from paroxysmal atrial fibrillation (AF). During cardiac catheterization, the hemodynamics were compared before and after cardioversion; that is, with AF and with sinus rhythm. The hemodynamic parameters worsened after conversion to sinus rhythm, with a significant decrease in heart rate, but improved with atrial pacing. Pacemaker implantation was performed to avoid bradycardia while keeping the sinus rhythm with amiodarone. As a result, the patient has been free from symptoms of heart failure for almost 1 year and her serum brain natriuretic peptide level also improved remarkably.

Adult↗