A feasible and automatic free tool for T1 and ECV mapping

Purpose: Cardiac magnetic resonance (CMR) is a useful non-invasive tool for characterizing tissues and detecting myocardial fibrosis and edema. Estimation of extracellular volume fraction (ECV) using T1 sequences is emerging as an accurate biomarker in cardiac diseases associated with diffuse fibrosis. In this study, automatic software for T1 and ECV map generation consisting of an executable file was developed and validated using phantom and human data. Methods: T1 mapping was performed in phantoms and 30 subjects (22 patients and 8 healthy subjects) on a 1.5T MR scanner using the modified Look-Locker inversion-recovery (MOLLI) sequence prototype before and 15 min after contrast agent administration. T1 maps were generated using a Fast Nonlinear Least Squares algorithm. Myocardial ECV maps were generated using both pre- and post-contrast T1 image registration and automatic extraction of blood relaxation rates. Results: Using our software, pre- and post-contrast T1 maps were obtained in phantoms and healthy subjects resulting in a robust and reliable quantification as compared to reference software. Coregistration of pre- and post-contrast images improved the quality of ECV maps. Mean ECV value in healthy subjects was 24.5% ± 2.5%. Conclusions: This study demonstrated that it is possible to obtain accurate T1 maps and informative ECV maps using our software. Pixel-wise ECV maps obtained with this automatic software made it possible to visualize and evaluate the extent and severity of ECV alterations

Introduction to morphological and functional evaluation of the heart and coronary arteries

In the last years, the number of clinical indications for the evaluation of the heart – with both computed tomography (CT) and magnetic resonance (MR) – exponentially grew. This evidence reflects the remarkable technological developments of both techniques allowing unprecedented spatial, temporal and contrast resolution levels and to comprehensively evaluate cardiac pathology, combining anatomical information with functional assessment and tissue characterization of myocardial diseases

Fatty images of the heart: spectrum of normal and pathological findings at computed tomography and cardiac magnetic resonance imaging.

Ectopic cardiac fatty images are not rarely detected incidentally at computed tomography and cardiac magnetic resonance, either in exams focused on the heart as in general thoracic imaging evaluations. A correct interpretation of these findings is essential in order to recognize their normal or pathological meaning, focusing on the eventually associated clinical implications. The development of techniques such as computed tomography and cardiac magnetic resonance allowed a detailed detection and evaluation of adipose tissue within the heart. This pictorial review illustrates the most common characteristics of cardiac fatty images at computed tomography and cardiac magnetic resonance, in a spectrum of normal and pathological conditions ranging from physiological adipose images to diseases presenting with cardiac fatty foci. Physiologic intramyocardial adipose tissue may normally be present in healthy adults, being not related to cardiac affections and without any clinical consequence. However cardiac fatty images may also be the expression of various diseases, comprehending arrhythmogenic right ventricular dysplasia, post-myocardial infarction lipomatous metaplasia, dilated cardiomyopathy and lipomatous hypertrophy of the inter-atrial septum. Fatty neoplasms of the heart as lipoma and liposarcoma are also described

Unexplained cardiac arrest after near drowning in a young experienced swimmer: insight from cardiovascular magnetic resonance imaging

Cardiac magnetic resonance imaging (cMRI) is a well-established noninvasive imaging modality in clinical cardiology. Its ability to provide tissue characterization make it well suited for the study of patients with cardiac diseases. We describe a multi-modality imaging evaluation of a 45-year-old man who experienced a near drowning event during swimming. We underline the unique capability of tissue characterization provided by cMRI, which allowed detection of subtle, clinically unrecognizable myocardial damage for understanding the causes of sudden cardiac arrest and also showed the small damages caused by cardiopulmonary resuscitation

Volumetric analysis of carotid plaque components and cerebral microbleeds: a correlative study

PURPOSE: The purpose of this work was to explore the association between carotid plaque volume (total and the subcomponents) and cerebral microbleeds (CMBs). MATERIALS AND METHODS: Seventy-two consecutive (male 53; median age 64) patients were retrospectively analyzed. Carotid arteries were studied by using a 16-detector-row computed tomography scanner whereas brain was explored with a 1.5 Tesla system. CMBs were studied using a T2*-weighted gradient-recalled echo sequence. CMBs were classified as from absent (grade 1) to severe (grade 4). Component types of the carotid plaque were defined according to the following Hounsfield unit (HU) ranges: lipid less than 60 HU; fibrous tissue from 60 to 130 HU; calcification greater than 130 HU, and plaque volumes of each component were calculated. Each carotid artery was analyzed by 2 observers. RESULTS: The prevalence of CMBs was 35.3%. A statistically significant difference was observed between symptomatic (40%) and asymptomatic (11%) patients (P value = .001; OR = 6.07). Linear regression analysis demonstrated an association between the number of CMBs and the symptoms (P = .0018). Receiver operating characteristics curve analysis found an association between the carotid plaque subcomponents and CMBs (Az = .608, .621, and .615 for calcified, lipid, and mixed components, respectively), and Mann-Whitney test confirmed this association in particular for the lipid components (P value = .0267). CONCLUSIONS: Results of this study confirm the association between CMBs and symptoms and that there is an increased number of CMBs in symptomatic patients. Moreover, we found that an increased volume of the fatty component is associated with the presence and number of CMBs

Impact of heart rate on myocardial salvage in timely reperfused patients with STSegment elevation myocardial infarction. new insights from cardiovascular magnetic resonance

BACKGROUND: Previous studies evaluating the progression of the necrotic wave in relation to heart rate were carried out only in animal models of ST-elevated myocardial infarction (STEMI). Aim of the study was to investigate changes of myocardial salvage in relation to different heart rates at hospital admission in timely reperfused patients with STEMI by using cardiovascular magnetic resonance (CMR). METHODS: One hundred-eighty-seven patients with STEMI successfully and timely treated with primary coronary angioplasty underwent CMR five days after hospital admission. According to the heart rate at presentation, patients were subcategorized into 5 quintiles: <55 bpm (group I, n = 44), 55-64 bpm (group II, n = 35), 65-74 bpm (group III, n = 35), 75-84 bpm (group IV, n = 37), ≥85 bpm (group V, n = 36). Area at risk, infarct size, microvascular obstruction (MVO) and myocardium salvaged index (MSI) were assessed by CMR using standard sequences. RESULTS: Lower heart rates at presentation were associated with a bigger amount of myocardial salvage after reperfusion. MSI progressively decreased as the heart rates increased (0.54 group I, 0.46 group II, 0.38 group III, 0.34 group IV, 0.32 group V, p<0.001). Stepwise multivariable analysis showed heart rate, peak troponin and the presence of MVO were independent predictor of myocardial salvage. No changes related to heart rate were observed in relation to area at risk and infarct size. CONCLUSIONS: High heart rates registered before performing coronary angioplasty in timely reperfused patients with STEMI are associated with a reduction in salvaged myocardium. In particular, salvaged myocardium significantly reduced when heart rate at presentation is ≥85 bpm

Significant coronary stenosis detected by coronary computed angiography in asymptomatic HIV infected subjects

Objectives: increased incidence of acute coronary events, high rate of abnormal surrogate markers of atherosclerosis and increased amount of coronary calcium have been described in HIV infected population. To expand knowledge on coronary artery disease (CAD) in HIV patients, cardiac CT scan was performed in asymptomatic subjects with low cardiovascular (CV) risk. Methods: A cross-sectional study using dual-source CT (MDCT) coronary angiography. was conducted in HIV-infected subjects with the following characteristics: Framingham Risk Score (FRS) <= 10, absence of metabolic syndrome, negative echocardiographic and ECG stress-test. A luminal narrowing exceeding 50% was defined as a clinically significant coronary stenosis. Calcium score was quantified using the Agatston Calcium Score method. Results: Fifty-five subjects were enrolled. Significant coronary stenoses, requiring coronary angiography, were found in 16/55 (29.1%). At multivariate analysis older age was the only variable independently associated with the presence of significant luminal narrowing (p = 0.011). Conclusions: MDCT showed an unexpected, age-associated high rate of significant coronary stenosis in asymptomatic HIV positive subjects with low CV risk. These findings suggest that aggressive screening programs for coronary artery disease may be appropriate in this population; further studies are recommended to assess the appropriateness of MDCT for this purpose. (C) 2011 The British Infection Association. Published by Elsevier Ltd. All rights reserved

The PocketLAI smartphone app: an alternative method for leaf area index estimation

The possibility of adopting the technology implemented in low-costs devices for the monitoring of biophysical processes is being increasingly explored by the scientific community. In the context of environmental studies, leaf area index (LAI) is one of the variables scientists and technicians are more interested in, since directly involved in radiation interception, and in crop response to water availability. An indirect method for leaf area index estimation was recently proposed and implemented in the smartphone app PocketLAI. The application uses the smartphone camera and the accelerometer to acquire images at 57.5° below the canopy while the user is rotating the device along its main axes. Images are automatically processed using a dedicated segmentation algorithm to derive the gap fraction. The PocketLAI was successfully evaluated for paddy rice canopies against data obtained with direct (planimetric) measurements, and results were compared with those provided by a number of commercial instruments. In a following study, PocketLAI was compared with AccuPAR ceptometer for canopies markedly deviating from the ideal assumption behind the simplified model for light transmittance into the canopy implemented in the app (i.e., random distribution of infinitely small leaves). Although a saturation effect was observed for dense canopies with big leaves (maize and giant reed) and a large number of measuring replicates was needed for markedly heterogeneous canopies (natural grassland), the overall positive results support the use of PocketLAI in context characterized by low portability or by limited economic resources. A step forward is here discussed by testing the performances of the app when installed on devices from different price categories and manufacturers, aiming at implementing automatic calibration facilities for entry-level smartphones

Early benralizumab for eosinophilic myocarditis in eosinophilic granulomatosis with polyangiitis

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Aortic valvular imaging with cardiovascular magnetic resonance: seeking for comprehensiveness

Cardiovascular magnetic resonance (CMR) has an emerging role in aortic valve disease evaluation (AVD), becoming an all-in-one technique. CMR evaluation of the anatomy and flow through the aortic valve has a higher reproducibility than echocardiography. Its unique ability of in-vivo myocardial tissue characterization, significantly improves the risk stratification and management of patients. In addition, CMR is equivalent to cardiac computed tomography angiography for trans-aortic valvular implantation and surgical aortic valve replacement planning; on the other hand, its role in the evaluation of ventricular function improving and post-treatment complications is undisputed. This review encompasses the existing literature regarding the role of CMR in AVD, exploring all the aspects of the disease, from diagnosis to prognosis