Quantitative analysis of pulmonary perfusion with dual-energy CT angiography: comparison of two quantification methods in patients with pulmonary embolism.

The study aimed to evaluate a quantification method of pulmonary perfusion with Dual-Energy CT Angiography (DE-CTA) normalized by lung density in the prediction of outcome in acute pulmonary embolism (PE). In this prospective study with CTA scans acquired with different breathing protocols, two perfusion parameters were calculated: %PBV (relative value of PBV, expressed per unit volume) and PBVm (PBV normalized by lung density, expressed per unit mass). DE-CTA parameters were correlated with simplified pulmonary embolism severity index (sPESI) and with outcome groups, alone and in combinationwith tomographic right-to-left ventricular ratios (RV/LV).

Lobar pulmonary perfusion quantification with dual-energy CT angiography: Interlobar variability and relationship with regional clot burden in pulmonary embolism.

Purpose: Semi-automated lobar segmentation tools enable an anatomical assessment of regional pulmonary perfusion with Dual-Energy CTA (DE-CTA). We aimed to quantify lobar pulmonary perfusion with DE-CTA, analyze the perfusion distribution among the pulmonary lobes in subjects without cardiopulmonary diseases and assess the correlation between lobar perfusion and regional endoluminal clots in patients with acute pulmonary embolism (PE).

Methods: We evaluated 151 consecutive subjects with suspected PE and without cardiopulmonary comorbidities.

Stent evaluation by coronary computed tomography angiography: a comparison between Iopamidol-370 and Ioversol-320 hypo-osmolar iodine concentration contrasts.

Objective: Qualitative and quantitative image analysis between Iopamidol-370 and Ioversol-320 in stents´ evaluation by coronary computed tomography angiography (CTA).

Methods: Sixty-five patients with low-risk stable angina undergoing stent follow-up with coronary CTA were assigned to Iopamidol I-370 ( = 33) or Ioversol I-320 ( = 32) in this prospective, double-blind, non-inferiority, randomized trial. Stent lumen image quality was graded by 5-point Likert Scale.

Association between perivascular inflammation and downstream myocardial perfusion in patients with suspected coronary artery disease.

Aims: To investigate the association between pericoronary adipose tissue (PCAT) computed tomography (CT) attenuation derived from coronary computed tomography angiography (CTA) and coronary flow reserve (CFR) by positron emission tomography (PET) in patients with suspected coronary artery disease (CAD).

Methods And Results: PCAT CT attenuation was measured in proximal segments of all major epicardial coronary vessels of 105 patients with suspected CAD. We evaluated the relationship between PCAT CT attenuation and other quantitative/qualitative CT-derived anatomic parameters with CFR by PET.

[Not Available].

Background: There are clinically important morphological differences in the Adamkiewicz artery (AKA) between populations that do and do not have aortic disease and they have an influence on the neuroischemic complications involving the spinal cord during surgical operations. It is not yet known whether clinical parameters correlate with the predictability of identification of the artery using angiotomography.

Objective: To develop a mathematical model that by correlating clinical parameters with atherosclerosis enables prediction of the probability of identification of the AKA in patients examined with angiotomography.

Radiation dose reduction by adjusting bolus tracking parameters in a 320-detector row scanner.

Background: The importance of bolus tracking (BT) regarding total effective radiation dose (ERD) in the era of advanced coronary computed tomography angiography (CTA) has been ignored. We aimed to investigate whether adjusting BT parameters reduces ERD.

Methods: Adults consecutively referred to CTA (n = 289) in a 320 detector-row scanner were distributed into four BT protocols according to delay time and time between intermittent scans, as follows: A (n = 70, delay 10s, intermittent scans 1s); B (n = 79, delay 10s, intermittent scans 2s); C (n = 68, delay 15s, intermittent scans 1s); and D (n = 72, delay 15s, intermittent scans 2s).

Myocardial T1 mapping and extracellular volume quantification in patients with left ventricular non-compaction cardiomyopathy.

Aims: From pathophysiological mechanisms to risk stratification and management, much debate and discussion persist regarding left ventricular non-compaction cardiomyopathy (LVNC). This study aimed to characterize myocardial T1 mapping and extracellular volume (ECV) fraction by cardiovascular magnetic resonance (CMR), and investigate how these biomarkers relate to left ventricular ejection fraction (LVEF) and ventricular arrhythmias (VA) in LVNC.

Methods And Results: Patients with LVNC (n = 36) and healthy controls (n = 18) were enrolled to perform a CMR with T1 mapping.

Myocardial perfusion in patients with suspected coronary artery disease: comparison between 320-MDCT and rubidium-82 PET.

Objectives: Despite advances in non-invasive myocardial perfusion imaging (MPI) evaluation, computed tomography (CT) multiphase MPI protocols have not yet been compared with the highly accurate rubidium-82 positron emission tomography (RbPET) MPI. Thus, this study aimed to evaluate agreement between RbPET and 320-detector row CT (320-CT) MPI using a multiphase protocol in suspected CAD patients.

Methods: Forty-four patients referred for MPI evaluation were prospectively enrolled and underwent dipyridamole stress RbPET and multiphase 320-CT MPI (five consecutive volumetric acquisitions during stress).

On the search of arterial geometry heritability.

Background: Geometrical risk factors for CAD have been previously proposed before. To date, however, the effect of those factors is not conclusive, and remains as an open research field. Here, we hypothesize that some of these factors have a genetic component explaining inter-individual variability.

Myocardial tissue characterization in Chagas' heart disease by cardiovascular magnetic resonance.

Background: Chagas' heart disease is an important public health problem in South America. Several aspects of the pathogenesis are not fully understood, especially in its subclinical phases. On pathology Chagas' heart disease is characterized by chronic myocardial inflammation and extensive myocardial fibrosis.

Dipyridamole stress myocardial perfusion by computed tomography in patients with left bundle branch block.

Background: Functional tests have limited accuracy for identifying myocardial ischemia in patients with left bundle branch block (LBBB).

Objective: To assess the diagnostic accuracy of dipyridamole-stress myocardial computed tomography perfusion (CTP) by 320-detector CT in patients with LBBB using invasive quantitative coronary angiography (QCA) (stenosis ≥ 70%) as reference; to investigate the advantage of adding CTP to coronary computed tomography angiography (CTA) and compare the results with those of single photon emission computed tomography (SPECT) myocardial perfusion scintigraphy.

Methods: Thirty patients with LBBB who had undergone SPECT for the investigation of coronary artery disease were referred for stress tomography.

The descending branch of the lateral femoral circumflex artery is a good option in CABG with arterial grafts.

Introduction: The descending branch of the lateral femoral circumflex artery is an option for coronary artery bypass grafting.

Objective: To evaluate the early patency and adaptation of lumen diameter using multidetector computed angiotomography.

Methods: Thirty-two patients were selected to undergo coronary artery bypass grafting using the descending branch of the lateral circumflex artery, the internal thoracic artery, and other grafts.

Exercise-induced decrease in myocardial high-energy phosphate metabolites in patients with Chagas heart disease.

Background: The influence of exercise on cardiac metabolic response in patients with Chagas disease is incompletely understood.

Methods And Results: Changes in cardiac energetic metabolism were investigated in Chagas disease patients before and during isometric handgrip exercise with (31)P magnetic resonance spectroscopy (MRS). Twenty-eight patients (10 with systolic dysfunction: group I; 10 with normal systolic function and electrocardiogram (ECG) abnormalities: group II; and 8 asymptomatic without ECG abnormalities: group III) and 8 healthy control subjects (group C) were evaluated by electrocardiogram, echocardiogram, functional tests for coronary artery disease, and image-selected localized cardiac (31)P-MRS.

Late gadolinium enhancement magnetic resonance imaging in the diagnosis and prognosis of endomyocardial fibrosis patients.

Background: Endocardial fibrous tissue (FT) deposition is a hallmark of endomyocardial fibrosis (EMF). Echocardiography is a first-line and the standard technique for the diagnosis of this disease. Although late gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) allows FT characterization, its role in the diagnosis and prognosis of EMF has not been investigated.

Evaluation of the metabolism of high energy phosphates in patients with Chagas' disease.

Background: Abnormalities in myocardial metabolism have been observed in patients with heart failure of different etiologies. Magnetic resonance spectroscopy (MRS) with phosphorus-31 is a noninvasive technique that allows detection of myocardial metabolic changes.

Objective: To determine the resting metabolism of high-energy phosphates in patients with Chagas' disease (CD) by MRS with phosphorus-31.

Coronary calcium score as predictor of stenosis and events in pretransplant renal chronic failure.

Background: Coronary artery disease (CAD) is the major cause of death among chronic renal failure (CRF) patients. Traditional, non-invasive exams to detect CAD and to predict events have shown insufficient results in this group. CT Scan evaluation of Coronary Calcium Score (CCS) has proven to be of prognostic value for the population reporting no renal condition.

Relation between visceral fat and coronary artery disease evaluated by multidetector computed tomography.

Visceral abdominal fat has been associated to cardiovascular risk factors and coronary artery disease (CAD). Computed tomography (CT) coronary angiography is an emerging technology allowing detection of both obstructive and nonobstructive CAD adding information to clinical risk stratification. The aim of this study was to evaluate the association between CAD and adiposity measurements assessed clinically and by CT.

Contrast-enhanced magnetic resonance imaging identifies focal regions of intramyocardial fibrosis in patients with severe aortic valve disease: Correlation with quantitative histopathology.

Background: Chronic aortic valve disease (AVD) is characterized by progressive accumulation of interstitial myocardial fibrosis (MF). However, assessment of MF accumulation has only been possible through histologic analyses of endomyocardial biopsies. We sought to evaluate contrast-enhanced magnetic resonance imaging (ce-MRI) as a noninvasive method to identify the presence of increased MF in patients with severe AVD.

Arsenic removal by electrocoagulation using combined Al-Fe electrode system and characterization of products.

Combination of electrodes, such as aluminum and iron in a single electrochemical cell provide an alternative method for removal of arsenic from water by electrocoagulation. The removal process has been studied with a wide range of arsenic concentration (1-1000 ppm) at different pH (4-10). Analysis of the electrochemically generated by-products by XRD, XPS, SEM/EDAX, FT-IR, and Mössbauer Spectroscopy revealed the expected crystalline iron oxides (magnetite (Fe3O4), lepidocrocite (FeO(OH)), iron oxide (FeO)) and aluminum oxides (bayerite (Al(OH)3), diaspore (AlO(OH)), mansfieldite (AlAsO(4).

CT angiography in highly calcified arteries: 2D manual vs. modified automated 3D approach to identify coronary stenoses.

Background: Two-dimensional axial and manually-oriented reformatted images are traditionally used to analyze coronary data provided by multidetector-row computed tomography angiography (MDCTA). While apparently more accurate in evaluating calcified vessels, 2D methods are time-consuming compared with automated 3D approaches. The purpose of this study was to evaluate the performance of a modified automated 3D approach (using manual vessel isolation and different window and level settings) in a population with high calcium scores who underwent coronary half-millimeter 16-detector-row CT angiography (16 x 0.

[Symptomatic severe chronic aortic valve disease: a comparative study of cardiac magnetic resonance imaging and echocardiography].

Objective: To show the real value of cardiac magnetic resonance imaging (CMRI) in the evaluation of patients with symptomatic chronic aortic valve disease.

Methods: Seventy patients--35 with aortic stenosis (AoS) and 35 with aortic regurgitation (AoR) with surgical indication, who underwent preoperative echocardiogram (ECHO) and CMRI to assess ventricular function, volumes, and left ventricular mass index using cine magnetic resonance imaging, were studied.

Results: No statistically significant difference was observed between the AoS and AoR groups when ECHO and CMRI variables were compared.

Myocardial delayed enhancement by magnetic resonance imaging in patients with Chagas' disease: a marker of disease severity.

Objectives: We sought to investigate whether myocardial delayed enhancement (MDE) by magnetic resonance imaging (MRI) could quantify myocardial fibrosis (MF) in patients with Chagas' heart disease (CHD), thus defining the severity of the disease.

Background: Myocardial fibrosis secondary to ischemic disease can be imaged using MDE. Advanced CHD is characterized by progressive MF.