Factors associated with perceived feasibility and willingness of non-psychiatric doctors in Japan to treat depressed patients.

Objectives: We previously reported that many non-psychiatric doctors in Japan believe that treating depression was not part of their duties. Educational interventions must address motivation of physicians to play a role in depression care. In this study, we explored factors associated with perceived feasibility and willingness of non-psychiatric doctors in Japan to treat depression.

Amlodipine has a preventive effect on temporal left ventricular hypokinesia after emotional stress compared with an angiotensin II receptor blocker.

Purpose: We previously reported that α- and β-blockers protected against emotional stress-induced cardiac dysfunction, but the protective effects of other antihypertensive drugs is unknown. The purpose of this study is to evaluate the ability of a calcium channel blocker, amlodipine, to prevent temporal left ventricular hypokinesia after emotional stress compared with an angiotensin II receptor blocker, olmesartan medoxomil.

Methods: Rats premedicated with amlodipine (0.

Monocrotaline-induced pulmonary hypertension with sufficient tricuspid regurgitation in a rat model.

Background And Purpose: It is well known that monocrotaline (MCT) induces pulmonary hypertension (PH) in rats. This model is very useful for understanding the physiology of PH and developing treatments for PH. However, it is very difficult to estimate pulmonary artery pressure (PAP) in this model.

Acute effects of beta-blocker with intrinsic sympathomimetic activity on stress-induced cardiac dysfunction in rats.

Background: We have reported that α and β adrenergic blockers could protect against emotional stress-induced cardiac dysfunction but those protective effects of β adrenergic blockers with intrinsic sympathomimetic activity (ISA), such as celiprolol, are unknown. The purpose of this study is to evaluate whether ISA could relate with this protective effect.

Methods And Results: Rats medicated with celiprolol (8 mg/kg), metoprolol (4 mg/kg), or vehicle, were restrained for 30 min (immobilization stress: IMO) to reproduce emotional stress, and anesthetized to release stress.

Attitudes toward depression among Japanese non-psychiatric medical doctors: a cross-sectional study.

Background: Under-recognition of depression is common in many countries. Education of medical staff, focusing on their attitudes towards depression, may be necessary to change their behavior and enhance recognition of depression. Several studies have previously reported on attitudes toward depression among general physicians.

Azelnidipine, unique calcium channel blocker could prevent stress-induced cardiac dysfunction like α·β blocker.

Background: We have reported that α and β adrenergic blockers could protect against emotional stress-induced cardiac dysfunction. Azelnidipine is a unique calcium blocker which does not increase heart rate. The purpose of this study is to evaluate the effect of azelnidipine to prevent stress-induced cardiac dysfunction.

Evaluation of left ventricular rotation by two-dimensional speckle tracking method and real-time three-dimensional echocardiography: comparison with MRI tagging method.

Background: Recently, it has become possible to evaluate left ventricular (LV) torsion by two-dimensional (2D) speckle tracking images. However, LV torsion is a three-dimensional (3D) performance, which per se cannot be assessed by the 2D speckle tracking method. The present study investigated the accuracy of the 2D speckle tracking method and real-time 3D echocardiography in measuring LV rotation, comparing with the MRI tagging method.

Assessment of myocardial ischemic memory using persistence of post-systolic thickening after recovery from ischemia.

Objectives: We sought to investigate the time course of post-systolic thickening (PST) and systolic abnormality after recovery from brief myocardial ischemia.

Background: Myocardial ischemic memory imaging, denoting the visualization of abnormalities provoked by ischemia and sustained even after restoration of perfusion, is desirable and allows after-the-fact recognition of ischemic insult. PST offers a sensitive marker of myocardial ischemia, but whether this abnormal thickening remains after relief from brief ischemia is unclear.

Assessment of dyssynchronous wall motion during acute myocardial ischemia using velocity vector imaging.

Objectives: The purpose of this study was to investigate the diagnostic value of velocity vector imaging (VVI) for detecting acute myocardial ischemia and whether VVI can accurately demonstrate the spatial extent of ischemic risk area.

Background: Using a tracking algorithm, VVI can display velocity vectors of regional wall motion overlaid onto the B-mode image and allows the quantitative assessment of myocardial mechanics. However, its efficacy for diagnosing myocardial ischemia has not been evaluated.

Catecholamines and estrogen are involved in the pathogenesis of emotional stress-induced acute heart attack.

Emotional stress triggers takotsubo cardiomyopathy in postmenopausal women. Clinical analysis of autonomic nervous function has revealed a transient increase of sympathetic nervous activity and decrease of vagal nervous activity. Immobilization (IMO) stress of rats can reproduce the electrocardiographic and left ventriculographic changes that occur in takotsubo cardiomyopathy, both of which are prevented by combined blockade of alpha- and beta-adrenoceptors.

Low testosterone levels in patients with mild hypertension recovered after antidepressant therapy in a male climacterium clinic.

Recently, middle-aged men who have begun frequently complaining of erectile dysfunction and nonspecific symptoms similar to those of postmenopausal women, visited a male climacterium clinic in Japan. Some patients, who were already taking antihypertensive medication, discontinued or reduced their dosages of antihypertensive medication after anti-depressant therapy. Forty-nine males over the age of 40 years were studied to evaluate the relationships between blood pressure, mental stress, and testosterone levels.

Effect of systemic blood pressure on microcollateral circulation evaluated by real-time contrast echocardiography.

Background: In acute myocardial infarction, residual collateral-derived myocardial blood flow (CBF) within the ischemic area is one of the major determinants of infarct size. Management of systemic blood pressure (sBP) related to maintain collateral circulation is still difficult. The aim of this study was to reveal the influence of sBP on the rescue of area at risk by collateral circulation.

Effect of sildenafil citrate (Viagra) on coronary flow in normal subjects.

Background: The purpose of this study was to evaluate the effect of sildenafil citrate (Viagra) on coronary function in normal subjects.

Methods: The study assessed mean blood pressure, left anterior descending coronary artery (LAD) flow, and echocardiographic variables before and 30 and 60 minutes after taking 50 mg of sildenafil citrate. The mean velocity of LAD flow was assessed with Doppler flow imaging.

Sildenafil citrate (Viagra) enhances vasodilatation by atrial natriuretic peptide in normal dogs.

Background: Sildenafil citrate (Viagra) is a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5, which might enhance the vasorelaxant and natriuretic actions of atrial natriuretic peptide (ANP) in patients with heart failure. The objective of this study was to examine the combined effect of Viagra on hemodynamic changes during infusion of exogenous ANP.

Methods And Results: Healthy male beagles were used to assess systemic blood pressure, pulmonary artery pressure (PAP), and plasma levels of cGMP.

[Myocardial perfusion abnormality induced by right ventricular pacing: real-time myocardial contrast echocardiography study].

Background And Objectives: False positive findings of coronary stenosis are frequently detected by exercise stress myocardial scintigraphy in patients with left bundle branch block (LBBB). We investigated the relationship between regional wall motion abnormality and myocardial perfusion abnormality at high right ventricular (RV) pacing rate in the region of the RV pacing (the ventricular septum) and the control region (the lateral wall) assuming exercise stress in patients with LBBB.

Methods: RV pacing was performed in 7 open chest canines.

Brief communications: visualization of coronary arteries in rats by 3-dimensional real-time contrast echocardiography.

Angiogenesis is under intense investigation to advance the treatment of various ischemic diseases. Small animals, such as mice and rats, are often used for this purpose. However, evaluating the structure of coronary arteries in small animals in situ is not easy.

Three-dimensional reconstruction of coronary arteriole plexus image by contrast echocardiography using a high-frequency transducer.

Objective: This study was established to examine the efficacy of a high-frequency liner probe for visualizing fine anatomy of coronary microcirculation.

Methods: The vessel size and its velocity-time integral at the anterior wall in dogs by real-time contrast echocardiography with high-frequency liner probe and pulse Doppler methods, and the coronary flow volume, were measured before and after adenosine triphosphate injection. A 3-dimensional (3D) image was reconstructed by the built-in 3D system using intermittent flash echocardiographic images.

Quantitative assessment of microcollateral recruitment during coronary occlusion using real-time intravenous myocardial contrast echocardiography.

Background: Residual collateral-derived myocardial blood flow (MBF) (A x beta) is important to protect against myocardial ischemia after acute coronary occlusion.

Methods: Recruitment of microcollateral was assessed in 22 dogs with left circumflex coronary artery occlusion by analysis of MBF and regional wall thickening (WT) using real-time myocardial contrast echocardiography.

Results: Video intensity and WT at the center of risk area were significantly lower than those at the border of risk area.

Chronic estrogen supplementation following ovariectomy improves the emotional stress-induced cardiovascular responses by indirect action on the nervous system and by direct action on the heart.

Background: Takotsubo cardiomyopathy is triggered by emotional or physical stress especially in post-menopausal women. A reduction in estrogen levels following menopause might underlie the high incidence of takotsubo cardiomyopathy.

Methods And Results: The left ventricular contraction between ovariectomized rats (OVX) and OVX with estrogen supplementation (OVX + E) while subjected to immobilization stress (IMO) was compared.

Corrected quantification method to determine myocardial blood flow using real-time myocardial contrast echocardiography.

Background: The quantitative assessment of myocardial blood flow using real-time myocardial contrast echocardiography is based on a replenishment of bubble density after bubble destruction by high-power ultrasound exposure (burst). However, all microbubbles in the myocardial vessels are not necessarily completely destroyed, which results in unreliable data of the replenishment curve analysis.

Objective: The aim of this study was to propose a corrected equation for the replenishment curve analysis based on the hypothesis in which the initial intensity just after burst should be equivalent to the baseline intensity before contrast infusion, and to examine whether the regional difference of myocardial perfusion parameters could be minimized by the use of corrected equation of replenishment curve.

Impact of the coronary flow reduction at rest on myocardial perfusion and functional indices derived from myocardial contrast and strain echocardiography.

Background: The severity of the coronary flow reduction that corresponds to myocardial perfusion and functional abnormalities remains unclear. We estimated the impact of various severities of flow-limiting coronary stenosis at rest on myocardial perfusion and functional indices from myocardial contrast echocardiography and tissue strain imaging and characterized the relationship between both the indices.

Methods: Four levels of flow-limiting stenoses (slight, mild, moderate, severe) of the left circumflex coronary artery were examined in 10 open-chest dogs.

A fundamental study for quantitative measurement of ultrasound contrast concentration by low mechanical index contrast ultrasonography.

Purpose: In high mechanical index (MI) contrast ultrasonography it has been shown that the power of contrast signal intensity (CI) has a strong linear correlation with the concentration of the ultrasound contrast agent under conditions of constant applied acoustic pressure. However, it is unclear whether the linearity is preserved in low-MI contrast ultrasonography. Thus, we investigated the relationship between ultrasound contrast concentration and CI in vitro.

Noninvasive quantification of regional ventricular function in rats: assessment of serial change and spatial distribution using ultrasound strain analysis.

Background: The optimal method for quantitative assessment of regional ventricular function in rats remains unclear. The goal of this study was to investigate the use of ultrasonic strain rate (SR) and strain analysis in evaluating the serial change and spatial distribution of regional contractile function in rats.

Methods: In all, 22 anesthetized rats underwent incremental dobutamine infusion (protocol 1) for assessment of serial change or underwent coronary ligation (protocol 2) for assessment of spatial distribution.

Myocardial contrast echocardiography assessment of acute changes in collateral perfusion of contralateral coronary artery with coronary flow reserve after coronary angioplasty.

Background: Coronary flow velocity reserve (CFVR) is used to evaluate the severity of epicardial and intramyocardial coronary artery disease. Collateral flow to an adjacent compromised myocardial territory may influence the CFVR of a specific artery.

Methods: To assess the impact of collateral flow on CFVR, we measured CFVR and assessed perfusion area (PA) with myocardial contrast echocardiography in the right coronary arteries of 18 patients with total/subtotal occlusion of the left anterior descending coronary artery before and after angioplasty.