Lung Ultrasound-Implemented Diagnosis of Acute Decompensated Heart Failure in the ED: A SIMEU Multicenter Study

BACKGROUND

Lung ultrasonography (LUS) has emerged as a noninvasive tool for the differential diagnosis of pulmonary diseases. However, its use for the diagnosis of acute decompensated heart failure (ADHF) still raises some concerns. We tested the hypothesis that an integrated approach implementing LUS with clinical assessment would have higher diagnostic accuracy than a standard workup in differentiating ADHF from noncardiogenic dyspnea in the ED.

METHODS

We conducted a multicenter, prospective cohort study in seven Italian EDs. For patients presenting with acute dyspnea, the emergency physician was asked to categorize the diagnosis as ADHF or noncardiogenic dyspnea after (1) the initial clinical assessment and (2) after performing LUS ("LUS-implemented" diagnosis). All patients also underwent chest radiography. After discharge, the cause of each patient's dyspnea was determined by independent review of the entire medical record. The diagnostic accuracy of the different approaches was then compared.

RESULTS

The study enrolled 1,005 patients. The LUS-implemented approach had a significantly higher accuracy (sensitivity, 97% [95% CI, 95%-98.3%]; specificity, 97.4% [95% CI, 95.7%-98.6%]) in differentiating ADHF from noncardiac causes of acute dyspnea than the initial clinical workup (sensitivity, 85.3% [95% CI, 81.8%-88.4%]; specificity, 90% [95% CI, 87.2%-92.4%]), chest radiography alone (sensitivity, 69.5% [95% CI, 65.1%-73.7%]; specificity, 82.1% [95% CI, 78.6%-85.2%]), and natriuretic peptides (sensitivity, 85% [95% CI, 80.3%-89%]; specificity, 61.7% [95% CI, 54.6%-68.3%]; n = 486). Net reclassification index of the LUS-implemented approach compared with standard workup was 19.1%.

CONCLUSIONS

The implementation of LUS with the clinical evaluation may improve accuracy of ADHF diagnosis in patients presenting to the ED.

TRIAL REGISTRY

Clinicaltrials.gov; No.: NCT01287429; URL: www.clinicaltrials.gov.

Rule out of acute aortic dissection with plasma matrix metalloproteinase 8 in the emergency department

Introduction

Matrix metalloproteinases (MMPs) are involved in aortic pathophysiology. Preliminary studies have detected increased plasma levels of MMP8 and MMP9 in patients with acute aortic dissection (AAD). However, the performance of plasma MMP8 and MMP9 for the diagnosis of AAD in the emergency department is at present unknown.

Methods

The levels of MMP8 and MMP9 were measured by ELISA on plasma samples obtained from 126 consecutive patients evaluated in the emergency department for suspected AAD. All patients were subjected to urgent computed tomography (CT) scan for final diagnosis.

Results

In the study cohort (N = 126), AAD was diagnosed in 52 patients and ruled out in 74 patients. Median plasma MMP8 levels were 36.4 (interquartile range 24.8 to 69.3) ng/ml in patients with AAD and 13.2 (8.1 to 31.8) ng/ml in patients receiving an alternative final diagnosis (P <0.0001). Median plasma MMP9 levels were 169.2 (93.0 to 261.8) ng/ml in patients with AAD and 80.5 (41.8 to 140.6) ng/ml in patients receiving an alternative final diagnosis (P = 0.001). The area under the curve (AUC) on receiver-operating characteristic (ROC) analysis of MMP8 and MMP9 for the diagnosis of AAD was respectively 0.75 and 0.70, as compared to 0.87 of D-dimer. At the cutoff of 3.6 ng/ml, plasma MMP8 had a sensitivity of 100.0% (95% CI, 93.2% to 100.0%) and a specificity of 9.5% (95% CI, 3.9% to 18.5%) and ruled out AAD in 5.6% of patients. Combination of plasma MMP8 with D-dimer increased the AUC on ROC analysis to 0.89. Presence of MMP8 <11.0 ng/ml and D-dimer <1.0 or <2.0 µg/ml provided a negative predictive value of 100% and ruled out AAD in 13.6% and 21.4% of patients respectively.

Conclusions

Low levels of plasma MMP8 can rule out AAD in a minority of patients. Combination of plasma MMP8 and D-dimer at individually suboptimal cutoffs could safely rule out AAD in a substantial proportion of patients evaluated in the emergency department.

Liver X receptor activation reduces angiogenesis by impairing lipid raft localization and signaling of vascular endothelial growth factor receptor-2

OBJECTIVE

Liver X receptors (LXRα, LXRβ) are master regulators of cholesterol homeostasis. In the endothelium, perturbations of cell cholesterol have an impact on fundamental processes. We, therefore, assessed the effects of LXR activation on endothelial functions related to angiogenesis in vitro and in vivo.

METHODS AND RESULTS

LXR agonists (T0901317, GW3965) blunted migration, tubulogenesis, and proliferation of human umbilical vein endothelial cells. By affecting endothelial cholesterol homeostasis, LXR activation impaired the compartmentation of vascular endothelial growth factor receptor-2 in lipid rafts/caveolae and led to defective phosphorylation and downstream signaling of vascular endothelial growth factor receptor-2 upon vascular endothelial growth factor-A stimulation. Consistently, the antiangiogenic actions of LXR agonists could be prevented by coadministration of exogenous cholesterol. LXR agonists reduced endothelial sprouting from wild-type but not from LXRα(-/-)/LXRβ(-/-) knockout aortas and blunted the vascularization of implanted angioreactors in vivo. Furthermore, T0901317 reduced the growth of Lewis lung carcinoma grafts in mice by impairing angiogenesis.

CONCLUSIONS

Pharmacological activation of endothelial LXRs reduces angiogenesis by restraining cholesterol-dependent vascular endothelial growth factor receptor-2 compartmentation and signaling. Thus, administration of LXR agonists could exert therapeutic effects in pathological conditions characterized by uncontrolled angiogenesis.

Early cardiovascular autonomic dysfunction, beta cell function and insulin resistance in obese adolescents

AIMS

The aim of this study was to assess the metabolic and cardiovascular autonomic phenotype in adolescent obesity.

METHODS

Eighteen non diabetic obese individuals and ten lean age-matched control adolescents were included in the study. All subjects underwent Oral Glucose Tolerance Test (OGTT) with insulin and glucose determination for the calculation of AUC, OGIS, QUICKI, and disposition index. Cardiovascular assessments included 24-hour Holter ECG for HRV measurements, ABP monitoring and echocardiography.

RESULTS

Obese adolescents had higher serum lipids, reduced insulin sensitivity and higher insulin resistance. Obese individuals showed indeed a normal beta-cell function, with insulin AUC and disposition index similar to controls. However, obese adolescents presented a progressive reduction ofvagal indexes (RMSSD, HF) and an increase in sympathetic indexes (LF, LF/HF), which correlated with OGIS and beta-cell function parameters.

CONCLUSION

Adolescent obesity is characterized by insulin resistance with normal beta-cell function. Metabolic modifications may lead to an early impairment of the autonomic pattern.

[Left ventricular diastolic function and dysfunction: a single cardiac target for various systemic diseases]

Several systemic and cardiac diseases cause an impairment of left ventricular filling or of the ability to maintain cardiac output, without an increase in end-diastolic pressure. Prevalence of diastolic dysfunction has been found to be higher than systolic dysfunction in most studies. Many physiological conditions (age, sex and body weight), and pathological processes, such as cardiac or systemic diseases, can increase the incidence of diastolic dysfunction. Early diagnosis of left ventricular diastolic impairment has been demonstrated to have important therapeutic implications. Several invasive or non-invasive methods to investigate diastolic properties of the left ventricle have been described; a large number of studies compared different parameters of diastolic function in order to find the most accurate: this is of particular prognostic relevance since diastolic dysfunction may remain asymptomatic for a long period before resulting in overt heart failure. The purpose of this article is to provide an extensive review of the contemporary literature regarding diastolic function assessment and its role in daily practice.