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Yoshihiro J Akashi

Publications and source records attributed to Yoshihiro J Akashi.

15 recordsLinked to original sources
PubMed2006

The significance of 123I-BMIPP delayed scintigraphic imaging in cardiac patients.

BACKGROUND: Earlier studies have not fully investigated the significance of radionuclide planar imaging in cardiac patients using the fatty acid analogue 123I-beta-methyl-iodophenylpentadecanoic acid (123I-BMIPP). OBJECTIVES: This study was to clarify the effectiveness of 123I-BMIPP in assessing the heart-to-mediastinum ratio (H/M) and myocardial washout rate (WR) in patients with heart disease. METHODS: Myocardial 123I-BMIPP imaging was performed in 33 patients (20 with chronic heart failure [CHF] and 13 with stable angina pectoris [AP]) and 11 control subjects. Myocardial 123I-BMIPP planner images were obtained 30 min (early image) and 4 h (delayed image) after tracer injection. The left ventricular ejection fraction (LVEF) was measured by quantitative gated single photon emission computed tomography. The concentration of plasma brain natriuretic peptide (BNP) was measured before the scintigraphic study. RESULTS: (1) Delayed H/M was much lower in CHF than in AP (1.93 +/- 0.37 vs. 2.21 +/- 0.38, p < 0.05) and controls (vs. 2.47 +/- 0.38, p < 0.001). (2) The WR in CHF and AP were higher than the WR in controls (39.8 +/- 12.7% and 38.7 +/- 11.1 vs. 27.9 +/- 10.2%, p < 0.01 and p < 0.05, respectively). (3) In all subjects, LVEF was correlated with delayed H/M (r = 0.39, p < 0.01). And, the BNP was correlated with both the WR (r = 0.36, p < 0.05) and delayed H/M (r = - 0.29, p = 0.05). CONCLUSION: These data strongly suggest that the delayed H/M and myocardial WR of 123I-BMIPP enhances the assessment of the myocardial fatty acid metabolism disorders in patients with heart disease in both masked and unmasked conditions.

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PubMed2006

Prognosis and therapy approaches of cardiac cachexia.

PURPOSE OF REVIEW: This review focuses on the prognostic implications and therapeutic approaches in cardiac cachexia - a syndrome that has been recognized for a long time, although it has only received increased attention lately. RECENT FINDINGS: Cardiac cachexia is a common and serious complication of chronic heart failure and associated with very poor prognosis, yet is often recognized by the clinicians only at late stage. Approximately 15% of heart failure patients will develop cardiac cachexia, defined by a 6% non-edematous, non-voluntary weight loss over a period of 6 months. Several studies have demonstrated that cardiac cachexia is a multi-factorial disease, which involves increased neurohormonal activity and immune abnormalities, resulting in hormonal and metabolic catabolic/anabolic imbalance of the body, leading to the loss of fat and lean mass and ultimately death. So far, there are no standardized therapies available for this disease. SUMMARY: Cardiac cachexia in heart failure patients is under-recognized and there is currently no causal therapy available. Several interesting treatment options exist, however, which have emerged recently, including appetite stimulants, hormones and 'classical' drugs, such as beta-blockers and ACE inhibitors.

Cachexia↗
PubMed2006

Functional capacity, skeletal muscle strength, and skeletal muscle volume in patients with myocardial infarction.

Previous studies have reported that skeletal muscle strength is closely related to exercise capacity in patients with myocardial infarction (MI). However, none of the previous studies have fully investigated the correlation between exercise capacity and the skeletal muscle volume (MV). Seventy patients with MI underwent symptom-limited cardiopulmonary exercise testing using a treadmill. The MV was evaluated by electrical impedance analysis and the maximal knee extension strength (Peak torque: PT) was measured by a Biodex. The subjects were divided into 2 groups according to the MV (group L, MV < 22 kg; group H, MV > or = 22 kg). The PT was positively and significantly correlated with the peak V(.)O(2) in both the L and H groups (r = 0.70 versus r = 0.71). The MV of the lower limbs was positively correlated with the peak V(.)O(2) in the L group (r = 0.57), but not in the H group. The lower limb MV was positively and significantly correlated with PT in the L group (r = 0.48), but not in the H group. The exercise capacity of patients with MI is thought to depend on both the strength and volume of the skeletal muscle. In MI patients with high muscle volume, exercise capacity was determined by skeletal muscle strength alone.

Electric Impedance↗
PubMed2006

Takotsubo-like left ventricular dysfunction in an HIV-infected patient.

Takotsubo cardiomyopathy (in Japanese language "takotsubo" is a fishing pot with a round bottom and a neck that is used for trapping octopuses) is a new syndrome, which is characterized by transient left ventricular dysfunction and by a typical left ventriculogram showing transient extensive akinesis of the apical and mid portions of the left ventricle with hypercontraction of the basal segment, from which this disease takes its name. Since 1990 sporadic cases of takotsubo cardiomyopathy were reported by Japanese authors, and only a few European reports are available. We report a case of takotsubo-like left ventricular dysfunction in an human immunodeficiency virus (HIV)-infected caucasian patient.

Adrenergic beta-Antagonists↗
PubMed2005

Takotsubo cardiomyopathy.

Recently, many reports have been published about apical ballooning or takotsubo cardiomyopathy. This disease is a new entity of acute reversible heart failure. Abnormal catecholamine dynamics due to stress may be the primary cause of this condition.

Cardiomyopathies↗
PubMed2005

Cachexia in chronic heart failure: prognostic implications and novel therapeutic approaches.

Cachexia in patients with chronic heart failure (CHF) has been recognized for a long time; however, it has not received much attention until recently. Cardiac cachexia, a common and serious complication of CHF, is associated with very poor prognosis. Several studies have demonstrated that increased neurohormonal and immune abnormalities may play a crucial role in the pathophysiology of cardiac cachexia. Hormonal and catabolic/anabolic imbalances of the body are likely to be responsible for the development of cachexia in CHF. Recently, ghrelin, a novel growth hormone-releasing peptide, has been widely noticed to have potential in the treatment of severe CHF and cardiac cachexia. However, further research will be necessary to identify the exact pathways involved and to find the best therapeutic strategies of using ghrelin to fight the wasting process.

Cachexia↗
PubMed2005

Reversible ventricular dysfunction takotsubo cardiomyopathy.

BACKGROUND: Recently, many cardiologists have recognized the existence of a rapidly reversible form of heart failure of unknown origin characterized by a takotsubo-shaped, dyskinetic left ventricle on left ventriculography. AIM: To determine the detailed clinical features of takotsubo cardiomyopathy. METHODS: Thirteen elderly patients (11 women and 2 men with a mean age of 75.3 years) who had normal coronary arteries and takotsubo-like left ventricular dysfunction were prospectively enrolled in this study. RESULTS: Cardiac enzymes did not increase significantly, but the mean plasma norepinephrine level was very high on admission (0.98 microg/l). Coronary angiography revealed normal coronary arteries in all patients, but left ventriculography showed apical akinesis combined with basal hyperkinesis, i.e., a takotsubo (Japanese octopus fishing pot)-shaped ventricle. Left ventricular wall motion normalized within a mean of 16.9 hospital days in 12 patients, but 1 patient died of acute renal failure on hospital day 7. Cardiac events did not recur during a follow-up period of 0.5 to 5 years. CONCLUSION: Takotsubo cardiomyopathy seems to be a new type of acute heart failure, which generally has a good prognosis and does not recur. Myocardial damage by catecholamine overload, adrenoceptor hypersensitivity, and changes of catecholamine dynamics due to stress may cause this condition.

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PubMed2005

Reversible left ventricular dysfunction (takotsubo cardiomyopathy) with deep negative T waves due to possible cardiac sympathetic denervation.

A case of characteristic left ventricular contraction disorder representing takotsubo cardiomyopathy after exercise is reported. A 58-year-old Japanese woman with no history of cardiac disease was admitted for chest oppression after exercise. A diagnosis of myocardial infarction was suspected because of her symptom, and the electrocardiographic and echocardiographic findings. Coronary angiography revealed normal arteries, while left ventriculography demonstrated asynergy with apical akinesis and basal hyperkinesis. Deep negative T waves were observed on the electrocardiogram on the second hospital day and sustained for over a month. Repeated measurements of heart rate viability and 123I-metaiodobenzylguanidine scintigraphy showed transient dysfunction of the cardiac autonomic nervous system. From these findings, it was concluded that cardiac autonomic denervation plays a pivotal role in the etiology of takotsubo cardiomyopathy.

Cardiomyopathies↗
PubMed2004

Left ventricular rupture associated with Takotsubo cardiomyopathy.

A 70-year-old woman was admitted to the hospital with chest discomfort after quarreling with her neighbors. Electrocardiography revealed ST-segment elevation in leads I, II, III, aVL, aVF, and V2 through V6. Coronary angiography demonstrated normal arteries, but left ventriculography showed apical akinesis and basal hyperkinesis. Takotsubo cardiomyopathy was diagnosed on the basis of these characteristic findings. The creatine kinase and creatine kinase-MB concentrations were elevated at admission and reached maximum levels 6 hours after admission. The plasma level of brain natriuretic peptide was 10.7 pg/mL (reference range, <18.4 pg/mL) on the first hospital day. ST-segment elevation in leads I, II, III, aVL, aVF, and V2 through V6 persisted at 72 hours after admission. On the third hospital day, sudden rupture of the left ventricle occurred, and despite extensive resuscitation efforts, the patient died. Takotsubo cardiomyopathy presents in a manner similar to that of acute myocardial infarction, but ventricular systolic function usually returns to normal within a few weeks. To our knowledge, this is the first reported case of fatal left ventricular rupture associated with takotsubo cardiomyopathy. We suggest that takotsubo cardiomyopathy may be a newly recognized cause of sudden cardiac death.

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PubMed2004

123I-MIBG myocardial scintigraphy in patients with "takotsubo" cardiomyopathy.

UNLABELLED: The clinical characteristics of reversible left ventricular dysfunction due to "takotsubo" cardiomyopathy have been described, but the origin of this condition remains unclear. This study investigated (123)I-metaiodobenzlguanidine ((123)I-MIBG) myocardial scintigraphy in patients with takotsubo cardiomyopathy. METHODS: Eight consecutive patients with takotsubo cardiomyopathy were studied. Left ventricular wall motion was monitored by echocardiography until wall motion normalized. (123)I-MIBG myocardial scintigrams were performed within 3 d of admission (0 mo) and after the improvement of left ventricular dysfunction (3 mo). Early images were obtained at 30 min after radioisotope injection and delayed images were obtained after 4 h. The heart-to-mediastinum ratio (H/M ratio) and the washout rate were calculated. RESULTS: The mean left ventricular ejection fraction improved significantly (from 42.8% +/- 8.7% to 66.5% +/- 7.9%; P < 0.0001) and normalized after 19.4 +/- 5.4 hospital days. The early H/M ratio was significantly higher than the late ratio at 0 mo (2.16 +/- 0.25 vs. 1.89 +/- 0.24, respectively; P < 0.05), but not at 3 mo. The washout rate was significantly greater at 0 mo than at 3 mo (39.1% +/- 10.2% vs. 25.4% +/- 6.3%, respectively; P < 0.05). CONCLUSION: In patients with takotsubo cardiomyopathy, initial (123)I-MIBG myocardial scintigraphy depicted a unique pattern of ventricular asynergy and indicated the existence of cardiac sympathetic hyperactivity, although coronary blood flow was maintained. These findings strongly suggest that takotsubo cardiomyopathy could be caused by neurogenic myocardial stunning.

3-Iodobenzylguanidine↗
PubMed2003

Reversible ventricular dysfunction (takotsubo cardiomyopathy) following polymorphic ventricular tachycardia.

A 67-year-old female with recurrent syncope and no obvious heart disease developed ventricular dysfunction, known as takotsubo cardiomyopathy, following a 90 s episode of polymorphic ventricular tachycardia originating from a ventricular extrasystole with a short coupling interval. Cardiac catheterization performed 30 min after the arrhythmic event revealed angiographically normal coronary arteries, and left ventricular apical akinesis and basal hyperkinesis. An intracoronary injection of acetylcholine revealed no inducible coronary spasm, and an electrophysiological study revealed normal atrioventricular conduction and no inducible ventricular arrhythmia. Thirty hours after the arrhythmic event, electrocardiography revealed deeply inverted T waves in leads V3 to V6, I, and aVL, which continued for more than a week. Although no treatment was given to maintain hemodynamic stability, echocardiography revealed normal left ventricular contraction 14 days after the onset of the ventricular dysfunction. The reversible ventricular dysfunction might have been induced by altered catecholamine dynamics due to the persistent syncope during the occurrence of tachycardia.

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PubMed2003

[Relationship between exercise capacity and brain natriuretic peptide in patients after cardiac surgery].

OBJECTIVES: Physical training in cardiac patients can increase exercise capacity and reduce plasma brain natriuretic peptide(BNP) concentration, but these effects may depend on the etiology of cardiac disease. The change in exercise capacity and BNP during the training period were investigated in patients with different cardiac diseases. METHODS: Ninety-one patients after coronary artery bypass grafting(CABG) and 78 patients after valve replacement (VR) underwent a symptom-limited incremental cardiopulmonary exercise test before (1 month) and 6 months after physical training. Anaerobic threshold and peak oxygen uptake(peak-Vo2) were measured during the cardiopulmonary exercise test. Before each cardiopulmonary exercise test, a blood sample was obtained in the resting condition for measuring BNP. RESULTS: Anaerobic threshold and peak-Vo2 were increased significantly from 1 month to 6 months in both groups. BNP in the CABG group indicated a tendency to decrease (194.6 +/- 155.3-->144.2 +/- 232.2 pg/ml, p < 0.1) from 1 month to 6 months. BNP in VR group was significantly decreased (159. 9 +/- 115.5-->112.8 +/- 131.7 pg/ml, p < 0.05) during the training period. The CABG group showed a significant negative correlation between peak-Vo2 and BNP at 1 month(r = -0.28, p < 0.01) and at 6 months(r = -0.39, p = 0.001). The VR group showed a significant negative correlation between peak-Vo2 and BNP at 6 months(r = -0.32, p < 0.01), but not at 1 month. CONCLUSIONS: Six months of physical training in patients after cardiac surgery may improve exercise capacity and reduce BNP. BNP concentration in the VR group before physical training did not reflect functional capacity.

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PubMed2002

Reversible left ventricular dysfunction "takotsubo" cardiomyopathy related to catecholamine cardiotoxicity.

An 80-year-old female was admitted for a persistent consciousness disturbance. Electrocardiography revealed ST-segment elevation in leads II, III, aVf, and V3-V6. Coronary angiography demonstrated normal arteries, while left ventriculography revealed asynergy of apical akinesis and basal hyperkinesis. The creatinine kinase and creatinine kinase MB levels were not elevated after the initial measurement on admission. The diffuse ST-segment elevation reached a maximum level 24 hours after admission. In leads V3-V6, ST-segment elevation continued for 48 hours, and was followed-up by deep inverted T waves. Within 24 days, the asynergy improved without any specific treatment, but the giant negative T waves were present on the electrocardiogram. The plasma norepinephrine and brain natriuretic peptide levels on the first hospital day were 2.9ng/mL and 906pg/mL, respectively. The left ventricular dysfunction appeared to be induced by the exposure to high-level plasma catecholamines. (123)I-metaiodobenzyl guanidine scintigraphy also revealed transient dysfunction of the cardiac catecholamine dynamics.

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PubMed2002

Short-term physical training improves vasodilatory capacity in cardiac patients.

There have been no previous studies that clearly demonstrate the effects of training on the relation between exercise capacity and vasodilatory capacity in skeletal muscle. This study was performed to clarify the effects of short-term, moderate-intensity physical training on exercise tolerance and vasodilatory capacity in cardiac patients. We studied 21 patients after acute myocardial infarction, coronary artery bypass grafting, or valve replacement. Each patient performed symptom-limited incremental exercise tests before and after a 2-week training program of moderate-intensity exercise. A cycle ergometer was used for both the training and exercise tests. Blood pressure measurement and respiratory gas analysis were continuously performed during the tests. Cardiac output was also measured using a dye-dilution method at rest and every 2 minutes during incremental exercise. Reactive hyperemic calf blood flow was measured at rest. After the training program, the subjects attained a significant decrease in systemic vessel resistance and significant increases in oxygen uptake and cardiac output at peak exercise. Changes in reactive hyperemic calf blood flow were significantly correlated with the changes in cardiac output, systemic vascular resistance, and the kinetics of oxygen uptake during warm-up exercise. By improving the peripheral vasodilatory capacity in these patients, short-term, moderate-intensity physical training was found to improve the cardiovascular adaptation not only at peak exercise, but also during the onset of exercise.

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