Diagnosis of myocardial viability by fluorodeoxyglucose distribution at the border zone of a low uptake region.

Purpose: In cardiac 2-[F-18]fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET) examination, interpretation of myocardial viability in the low uptake region (LUR) has been difficult without additional perfusion imaging. We evaluated distribution patterns of FDG at the border zone of the LUR in the cardiac FDG-PET and established a novel parameter for diagnosing myocardial viability and for discriminating the LUR of normal variants.

Materials And Methods: Cardiac FDG-PET was performed in patients with a myocardial ischemic event (n = 22) and in healthy volunteers (n = 22).

Activator of G protein signaling 8 (AGS8) is required for hypoxia-induced apoptosis of cardiomyocytes: role of G betagamma and connexin 43 (CX43).

Ischemic injury of the heart is associated with activation of multiple signal transduction systems including the heterotrimeric G-protein system. Here, we report a role of the ischemia-inducible regulator of G betagamma subunit, AGS8, in survival of cardiomyocytes under hypoxia. Cultured rat neonatal cardiomyocytes (NCM) were exposed to hypoxia or hypoxia/reoxygenation following transfection of AGS8siRNA or pcDNA::AGS8.

C-reactive protein predicts non-target lesion revascularization and cardiac events following percutaneous coronary intervention in patients with angina pectoris.

Background: C-reactive protein (CRP) plays a pivotal role in the pathogenesis of atherosclerosis progression. We hypothesized that CRP might be related to progression of non-target lesion and prognosis in patients with angina pectoris.

Methods And Results: We enrolled 111 patients with angina pectoris treated with coronary stenting.

Development of cardiac dysfunction induced by repetitive transient myocardial ischemia is inhibited by edaravone in conscious rats.

1. In the present study, we investigated the effects of treatment with the hydroxyl radical scavenger 3-methyl-1-phenyl-2-pyrazolin-5-one (edaravone) on myocardial dysfunction induced by transient but frequent ischaemia in conscious rats. 2.

Quantitative measurement of mitral valve coaptation in functional mitral regurgitation: In vivo experimental study by real-time three-dimensional echocardiography.

Background: The degree of mitral valve (MV) coaptation should be an important parameter in the assessment of functional mitral regurgitation (MR). This study aimed to quantify the degree of MV coaptation in experimental models of functional MR caused by acute left ventricular (LV) pressure overload, using real-time three-dimensional (3D) echocardiography.

Methods And Results: Using canine models, LV pressure overload was induced by staged ascending aortic banding.

C-Reactive protein predicts severity, progression, and prognosis of asymptomatic aortic valve stenosis.

Background: C-Reactive protein (CRP) has been shown to play a pivotal role in the pathogenesis of atherosclerosis progression. The aim of this study was to assess whether CRP predicts severity, progression, and prognosis of aortic valve stenosis (AS).

Methods: One hundred and thirty-five patients with asymptomatic AS were studied.

Mechanism of increasing systolic coronary flow velocity in patients with aortic regurgitation.

Background And Aim Of The Study: The mechanism of increasing systolic coronary flow velocity of the epicardial coronary artery in patients with aortic regurgitation (AR) has not been well investigated. Thus, an evaluation was made of the flow velocity pattern of the epicardial coronary artery in these patients.

Methods: In 12 patients with AR, epicardial coronary flow velocity was monitored using Doppler guidewire, and diameter changes of the epicardial coronary artery using intravascular ultrasound (IVUS).

Local release of catecholamines from the hearts of patients with tako-tsubo-like left ventricular dysfunction.

Background: The precise mechanism of tako-tsubo-like left ventricular (LV) dysfunction remains unclear, although recent studies have shown that activation of sympathetic tone might be involved. However, local release of catecholamines from cardiac sympathetic efferent neurons in patients with tako-tsubo-like LV dysfunction remains poorly understood. The purpose of this study was to investigate evidence of local release of catecholamines from the hearts of patients with tako-tsubo-like LV dysfunction.

Histological characteristics of plaque with ultrasonic attenuation: a comparison between intravascular ultrasound and histology.

Objectives: Intermediate echogenic plaque without acoustic shadow on intravascular ultrasound (IVUS) imaging has been recognized as fibrous plaque. Such echogenic plaque with ultrasonic attenuation may have higher risk for distal flow disturbance (slow flow/no-reflow) during percutaneous coronary intervention. However, histological evaluation of plaque with ultrasonic attenuation has not been performed.

The relationship between coronary plaque characteristics and small embolic particles during coronary stent implantation.

Objectives: We investigated the relationship between coronary plaque components and small embolic particles during stenting and examined the influence on the coronary microcirculation.

Background: In vivo tissue characterization of atherosclerotic plaques was introduced by the Virtual Histology intravascular ultrasound (VH-IVUS) system (Volcano Therapeutics, Inc., Rancho Cordova, California).

Relationship between coronary remodeling and plaque characterization in patients without clinical evidence of coronary artery disease.

Aims: The objectives of this study were: (1) to evaluate the relationship between coronary arterial remodeling assessed by intravascular ultrasound (IVUS) and plaque morphology assessed by histological examination in patients without clinical evidence of coronary artery disease and (2) to compare plaque morphology between histological examination and optical coherence tomography (OCT).

Methods: Coronary segments (n=98) were harvested from the heart of 34 patients who died without clinical evidence of coronary artery disease. The segments with remodeling were assessed by IVUS and compared with corresponding OCT and histological images.

Edaravone preserves coronary microvascular endothelial function after ischemia/reperfusion on the beating canine heart in vivo.

We examined whether edaravone (3-methyl-1-phenyl-2-pyrazolin-5-one), a free radical scavenger, exerts its protective effect on coronary microvessels after ischemia/reperfusion (I/R) in vivo. Ninety-minute coronary occlusion followed by reperfusion was performed in 16 open-chest dogs with and without edaravone administration. Coronary small artery (> or = 100 microm in size) and arteriolar (< 100 microm) vasodilation, in the presence of endothelium-dependent (acetylcholine) or -independent (papaverine) vasodilators, was directly observed using intravital microscopy before and after I/R.

Three-dimensional quantitation of mitral valve coaptation by a novel software system with transthoracic real-time three-dimensional echocardiography.

We investigated the degree of mitral valve coaptation with a custom quantitation software system using transthoracic three-dimensional (3D) echocardiography. With real-time 3D echocardiography, we obtained transthoracic volumetric images in 20 healthy subjects and 20 patients with dilated cardiomyopathy. With our novel software system, the surface area of mitral valve tenting in the onset of mitral leaflet closure [O] and the timing of maximum closure of mitral leaflet [M] were reconstructed for quantitative measurement.

Rapid progression of mild to moderate aortic stenosis in patients older than 80 years.

Objective: The purpose of this study was to evaluate the rate of progression of mild and moderate aortic stenosis in patients aged 80 years and older.

Methods: In all, 41 patients with mild and moderate aortic stenosis were included and divided into two groups by age: 19 patients aged 80 years and older (mean 84 +/- 4 years), and 21 patients younger than 80 years (mean 66 +/- 6 years).

Results: The rate of degression of aortic valve area was more rapid in the 80 years and older age group than that in the younger than 80 years age group (-0.

Novel rat model of ischemic cardiomyopathy induced by repetitive myocardial ischemia/reperfusion injury while conscious.

Background: A rodent model of ischemic cardiomyopathy (ICM) induced by repetitive brief ischemia/reperfusion (I/R) injury while conscious has not been previously established.

Methods And Results: A newly developed coronary occluder was implanted in male Wistar rats. A repetitive I/R protocol (20 s, 2 min, followed by main 30 min--ischemia, every 48 h, for 4 weeks) was introduced while the animals were conscious.

Assessment of the histological characteristics of coronary arterial plaque with severe calcification.

Background: Several studies have shown that rotational atherectomy (RA) is associated with higher rates of the slow-flow phenomenon and that ablated particles may be the possible cause. Intravascular ultrasound (IVUS) has an intrinsic limitation in assessing plaque morphology behind the calcification because of acoustic shadowing. Therefore, the purpose of this study was to investigate plaque characteristics behind severe calcification by histological examination.

Measurement of the thickness of the fibrous cap by optical coherence tomography.

Background: Identification of the fibrous cap is important because its thickness is a major determinant of plaque vulnerability in lipid-rich plaque. Thus, a high-resolution imaging technique may be a promising method for the identification of the fibrous cap within lipid-rich plaque. The purpose of this study was to investigate the feasibility of using optical coherence tomography (OCT) to measure the thickness of the fibrous cap within lipid-rich plaque.

Rate of progression of valvular aortic stenosis in patients undergoing dialysis.

Background: In patients undergoing dialysis, aortic valve calcification and aortic stenosis are frequently found. However, the rate of progression of aortic stenosis is still unclear.

Methods: In all, 55 consecutive patients undergoing dialysis were followed up by echocardiography for a period of 12 months.

Assessment of coronary arterial thrombus by optical coherence tomography.

We analyzed optical coherence tomographic (OCT) characteristics of different types of coronary thrombi that had been confirmed at postmortem histologic examination. We examined 108 coronary arterial segments of 40 consecutive human cadavers. OCT images of red and white thrombi were obtained and the intensity property of these thrombi was analyzed.

Assessment of coronary arterial plaque by optical coherence tomography.

The purpose of this study was to analyze the ability of optical coherence tomography (OCT) to identify coronary arterial plaque diagnosed by histologic examination. We examined 166 sections from 108 coronary arterial segments of 40 consecutive human cadavers (24 men and 16 women; mean age 74 +/- 7 years). The plaque type was classified as fibrous (n = 43), fibrocalcific (n = 82), or lipid-rich (n = 41).

Geometric differences of the mitral valve tenting between anterior and inferior myocardial infarction with significant ischemic mitral regurgitation: quantitation by novel software system with transthoracic real-time three-dimensional echocardiography.

We sought to investigate the 3-dimensional geometric differences of mitral leaflet tenting in ischemic mitral regurgitation, comparing inferior and anterior myocardial infarction (MI). Using real-time 3-dimensional echocardiography, we obtained transthoracic volumetric images for patients with significant ischemic mitral regurgitation (9 inferior and 7 anterior). With our novel software system, 3-dimensional images of the leaflets were reconstructed for quantitation.

Identification of a receptor-independent activator of G protein signaling (AGS8) in ischemic heart and its interaction with Gbetagamma.

As part of a broader effort to identify postreceptor signal regulators involved in specific diseases or organ adaptation, we used an expression cloning system in Saccharomyces cerevisiae to screen cDNA libraries from rat ischemic myocardium, human heart, and a prostate leiomyosarcoma for entities that activated G protein signaling in the absence of a G protein coupled receptor. We report the characterization of activator of G protein signaling (AGS) 8 (KIAA1866), isolated from a rat heart model of repetitive transient ischemia. AGS8 mRNA was induced in response to ventricular ischemia but not by tachycardia, hypertrophy, or failure.

Visualization of neointima formation by optical coherence tomography.

Optical coherence tomography (OCT) has recently been proposed as a high-resolution imaging method. Our male patient, who had been treated with a coronary stent, died due to acute leukemia. Coronary artery images using intravascular ultrasound (IVUS) and OCT were obtained postmortem.