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Purpose. To evaluate the influence of effective energy on computed tomography (CT) number in monoenergetic images (MEIs). Methods. Three bottle phantoms filled with water, oil, and a contrast agent were scanned at 100 and 140 kVp tube energy with a dual-source CT scanner. Cardiac dual-energy CT data was collected from 17 patients. CT numbers were measured in the 3 phantom materials and in the left ventricular cavity, myocardium, pericardial fat, and vertebral bone in MEIs from 40 to 190 keV. Results. In the phantoms, the mean CT number increased in oil whereas it decreased in the contrast agent as the energy level increased (). In clinical subjects, the mean CT numbers for the left ventricular cavity, myocardium, and vertebral bone were highest in the 40 keV images () and decreased as the energy level increased. In contrast, the CT number for pericardial fat was lowest in the 40 keV images () and increased with increasing energy. Conclusions. The influence of effective energy on CT number varies with material and tissue type in monoenergetic cardiac imaging, which could evaluate tissue characteristics through assessment of the changes in CT number associated with effective energies.

Soluble fms-like tyrosine kinase-1 (sFlt-1), an endogenous inhibitor of vascular endothelial growth factor and placental growth factor, is involved in the pathogenesis of cardiovascular disease. However, the significance of sFlt-1 in heart failure has not been fully elucidated. We found that sFlt-1 is decreased in renal failure and serves as a key molecule in atherosclerosis. In this study, we aimed to investigate the role of the decreased sFlt-1 production in heart failure, using sFlt-1 knockout mice. sFlt-1 knockout mice and wild-type mice were subjected to transverse aortic constriction and evaluated after 7 days. The sFlt-1 knockout mice had significantly higher mortality (52% versus 15%; P=0.0002) attributable to heart failure and showed greater cardiac hypertrophy (heart weight to body weight ratio, 8.95±0.45 mg/g in sFlt-1 knockout mice versus 6.60±0.32 mg/g in wild-type mice; P<0.0001) and cardiac dysfunction, which was accompanied by a significant increase in macrophage infiltration and cardiac fibrosis, than wild-type mice after transverse aortic constriction. An anti-placental growth factor-neutralizing antibody prevented pressure overload-induced cardiac hypertrophy, fibrosis, and cardiac dysfunction. Moreover, monocyte chemoattractant protein-1 expression was significantly increased in the hypertrophied hearts of sFlt-1 knockout mice compared with wild-type mice. Monocyte chemoattractant protein-1 inhibition with neutralizing antibody ameliorated maladaptive cardiac remodeling in sFlt-1 knockout mice after transverse aortic constriction. In conclusion, decreased sFlt-1 production plays a key role in the aggravation of cardiac hypertrophy and heart failure through upregulation of monocyte chemoattractant protein-1 expression in pressure-overloaded heart. [ABSTRACT FROM AUTHOR]

Background: Despite marked improvements in treatment strategies for heart failure (HF), the mortality rate of elderly patients with HF is still high. Detailed causes of death have not been fully understood. Methods and Results: We studied 459 consecutive patients with acute decompensated HF (ADHF) emergently admitted to our hospital from 2007 to 2011. Patients were divided into 2 groups: <75 years old (younger group; n = 225) and ≥ 75 years old (elderly group; n = 234). All-cause death, cardiovascular death, and noncardiovascular death were assessed as adverse outcomes. Compared with the younger group, the elderly group was characterized by a higher proportion of women and hypertensive patients and higher left ventricular ejection fraction. During a mean follow-up of 20.7 months, a total of 174 patients (37.9%) died. All-cause death was significantly higher in the elderly group than in the younger group (46.6% vs 28.9%; P < .0001), and this difference was caused by an increase in noncardiovascular deaths (20.9% vs 9.3%; P < .001), especially deaths due to infection (10.7% vs 4.0%; P < .01). Cardiovascular deaths did not differ between the 2 groups. Conclusions: Noncardiovascular deaths, most of which were caused by infection, were frequent among elderly patients with ADHF. [ABSTRACT FROM AUTHOR]

Background: Evaluation of left ventricular (LV) diastolic function is essential for the management of heart failure. We verified whether LV diastolic function could be evaluated by measuring the fractional area change (FAC) using cine cardiovascular magnetic resonance (CMR). Methods: We collected clinical data from 59 patients who underwent echocardiography and cine CMR. Normal, impaired relaxation, pseudonormal, and restrictive LV filling were observed in 15, 28, 11, and 5 patients, respectively. We calculated FAC during the first 30% of diastole (diastolic-index%) in the short-axis view, by tracing the contours on only three MR cine images. Results: The diastolic index was significantly lower (p < 0.0001) in patients with impaired relaxation (32.4 ± 7.5), pseudonormal filling (25.4 ± 5.6), and restrictive filling (9.5 ± 1.5) compared to those with normal diastolic function (67.7 ± 10.8), and the index decreased significantly with worsening of diastolic dysfunction. The diastolic index correlated positively with early diastolic mitral annular velocity measured by tissue Doppler imaging (r = 0.75, p < 0.0001), respectively. Conclusions: Measurement of FAC can be useful for the evaluation of LV diastolic function using cine CMR. [ABSTRACT FROM AUTHOR]