Robson Macedo

Positive remodeling of the coronary arteries detected by magnetic resonance imaging in an asymptomatic population: MESA (Multi-Ethnic Study of Atherosclerosis).

OBJECTIVES The purpose of this study was to assess coronary arterial remodeling as a marker of subclinical atherosclerosis using coronary wall magnetic resonance imaging (MRI) in an asymptomatic population-based cohort. BACKGROUND In early atherosclerosis, compensatory enlargement of both the outer wall of the vessel as well as the lumen, termed compensatory enlargement or positive remodeling, occurs before luminal narrowing. METHODS One hundred seventy-nine participants in the MESA (Multi-Ethnic Study of Atherosclerosis) trial were evaluated using black-blood coronary wall MRI. Coronary cross-sectional area (vessel size), lumen area, and mean wall thickness of the proximal coronary arteries were measured. RESULTS Men had a greater vessel size, lumen area, and mean wall thickness than women (38.3 +/- 11.3 mm2 vs. 32.6 +/- 9.4 mm2, 6.7 +/- 3.2 mm2 vs. 5.3 +/- 2.4 mm2, and 2.0 +/- 0.3 mm vs. 1.9 +/- 0.3 mm, respectively, p < 0.05). No significant coronary artery narrowing was present by magnetic resonance angiography. Overall, coronary vessel size increased 25.9 mm2 per millimeter increase in coronary wall thickness, whereas lumen area increased only slightly at 3.1 mm2 for every millimeter increase in wall thickness (difference in slopes, p < 0.0001). Adjusting for age and sex, participants with an Agatston score >0 were more likely to have wall thickness >2.0 mm (odds ratio: 2.0, 95% confidence interval: 1.01 to 3.84). CONCLUSIONS Coronary wall MRI detected positive arterial remodeling in asymptomatic men and women with subclinical atherosclerosis.

MRI detects increased coronary wall thickness in asymptomatic individuals: The multi-ethnic study of atherosclerosis (MESA)

To evaluate the use of coronary wall MRI as a measure of atherosclerotic disease burden in an asymptomatic population free of clinical cardiovascular disease. Coronary wall magnetic resonance imaging (MRI) is a noninvasive method for evaluation of arterial wall remodeling associated with atherosclerosis.

Cardiac Cine MRI: Quantification of the Relationship Between Fast Gradient Echo and Steady-State Free Precession for Determination of Myocardial Mass and Volumes

To determine the correlation function between the steady‐state free precession (SSFP) and fast gradient echo (FGRE) cine MRI pulse sequences for measuring the myocardial mass and volumes.

The Association of Pericardial Fat with Coronary Artery Plaque Index at MR Imaging: The Multi-Ethnic Study of Atherosclerosis (MESA)

PURPOSE To determine the relationship of pericardial fat, which secretes proinflammatory markers that have been implicated in coronary atherosclerosis, with atherosclerotic plaque in an asymptomatic population-based cohort. MATERIALS AND METHODS In this institutional review board-approved study, all participants supplied written informed consent. One hundred eighty-three participants (89 women, 94 men; mean age, 61 years ± 9 [standard deviation]) from the community-based Multi-Ethnic Study of Atherosclerosis (MESA) were included. The coronary artery eccentricity (ratio of maximal to minimal coronary artery wall thickness) was determined by using magnetic resonance (MR) imaging and served as an index of plaque burden. The pericardial fat volume was determined by using computed tomography. Linear regression coefficient analysis was used to correlate pericardial fat volume with coronary artery wall thickness and plaque eccentricity. RESULTS Pericardial fat volume correlated significantly with degree of plaque eccentricity (P < .05) in both men and women. After adjustments for body mass index (BMI) and waist circumference, traditional risk factors, C-reactive protein level, and coronary artery calcium content, the relationship between pericardial fat and plaque eccentricity remained significant in men (P < .01) but not in women. BMI and waist circumference correlated with degree of plaque eccentricity in the univariate model (P < .05) but not after adjustment for pericardial fat volume or traditional risk factors. CONCLUSION Pericardial fat volume, rather than BMI and waist circumference, was more strongly related to plaque eccentricity as a measure of coronary atherosclerotic plaque burden. The results support the proposed role of pericardial fat in association with atherosclerosis.

Marked Lipomatous Infiltration of the Right Ventricle: MRI Findings in Relation to Arrhythmogenic Right Ventricular Dysplasia

OBJECTIVE The purpose of this study was to describe the structure and function of the heart in the presence of marked lipomatous infiltration of the right ventricular wall in 13 patients referred for second opinions about fatty infiltration of the right ventricular wall and suspected arrhythmogenic right ventricular dysplasia. CONCLUSION Lipomatous infiltration with right ventricular thickness > or = 6 mm on MRI but without regional or global functional abnormalities of the right ventricle appears to be distinct from fatty right ventricle associated with arrhythmogenic right ventricular dysplasia. The finding of right ventricular fat must be interpreted cautiously to avoid the pharmacologic and defibrillator intervention associated with management of arrhythmogenic right ventricular dysplasia.

Magnetic resonance imaging in the evaluation of non-ischemic cardiomyopathies: current applications and future perspectives.

Patients with non-ischemic cardiomyopathy often represent a diagnostic challenge, and correct etiologic diagnosis may influence outcomes. Lately, delayed myocardial enhancement MR imaging has been developed and is currently being used for a growing number of clinical applications. On delayed enhancement MR images, scarring or fibrosis appears as an area of high signal intensity, and the pattern by which this enhancement occurs in the myocardium allows distinction of many different pathologies. In nonischemic cardiomyopathy, the delayed enhancement usually does not occur in a coronary artery distribution and is often midwall rather than subendocardial or transmural. It could also guide myocardial biopsy to an affected area, increasing its yield. Cardiac magnetic resonance imaging has now a definitive role in clinical practice, and its capability to non-invasively provide high resolution images of the heart with good tissue characterization is redefining the understanding of the conditions that can adversely affect the myocardium.

MRI to assess arrhythmia and cardiomyopathies.

Cardiovascular magnetic resonance (CMR) is highly precise for morphological and functional analyses of the myocardium, and has been used to assess different types of cardiomyopathies. Its ability to characterize tissue, especially with gadolinium (Gd) delayed‐enhancement techniques, has shown promising results for the diagnosis of arrhythmogenic cardiomyopathies. In this review we discuss the background and potential of this approach, as well as its usefulness for assessing arrhythmias and cardiomyopathies. J. Magn. Reson. Imaging 2006.

MRI to assess arrhythmia and cardiomyopathies: Relationship to echocardiography

Cardiomyopathies are a group of diseases that are associated with myocardial dysfunction and/or arrhythmia due to abnormalities of the myocardium. Echocardiography is the most commonly used method for functional evaluation and classification of cardiomyopathy since it is widely available. Magnetic resonance imaging (MRI) has recently emerged as a well‐validated diagnostic tool for the understanding and treatment of these conditions. Morphological and functional information can be achieved with a high level of accuracy and reproducibility. This article reviews the applications of MRI in relationship to echocardiography for the diagnosis of cardiomyopathy and arrhythmogenic conditions of the heart.

Positive Remodeling of the Coronary Arteries Detected by Magnetic Resonance Imaging in an Asymptomatic Population

OBJECTIVES The purpose of this study was to assess coronary arterial remodeling as a marker of subclinical atherosclerosis using coronary wall magnetic resonance imaging (MRI) in an asymptomatic population-based cohort. BACKGROUND In early atherosclerosis, compensatory enlargement of both the outer wall of the vessel as well as the lumen, termed compensatory enlargement or positive remodeling, occurs before luminal narrowing. METHODS One hundred seventy-nine participants in the MESA (Multi-Ethnic Study of Atherosclerosis) trial were evaluated using black-blood coronary wall MRI. Coronary cross-sectional area (vessel size), lumen area, and mean wall thickness of the proximal coronary arteries were measured. RESULTS Men had a greater vessel size, lumen area, and mean wall thickness than women (38.3 +/- 11.3 mm2 vs. 32.6 +/- 9.4 mm2, 6.7 +/- 3.2 mm2 vs. 5.3 +/- 2.4 mm2, and 2.0 +/- 0.3 mm vs. 1.9 +/- 0.3 mm, respectively, p < 0.05). No significant coronary artery narrowing was present by magnetic resonance angiography. Overall, coronary vessel size increased 25.9 mm2 per millimeter increase in coronary wall thickness, whereas lumen area increased only slightly at 3.1 mm2 for every millimeter increase in wall thickness (difference in slopes, p < 0.0001). Adjusting for age and sex, participants with an Agatston score >0 were more likely to have wall thickness >2.0 mm (odds ratio: 2.0, 95% confidence interval: 1.01 to 3.84). CONCLUSIONS Coronary wall MRI detected positive arterial remodeling in asymptomatic men and women with subclinical atherosclerosis.

Positive remodeling of the coronary arteries detected by MRI in an asymptomatic population: the Multi-Ethnic Study of Atherosclerosis (MESA)

OBJECTIVES The purpose of this study was to assess coronary arterial remodeling as a marker of subclinical atherosclerosis using coronary wall magnetic resonance imaging (MRI) in an asymptomatic population-based cohort. BACKGROUND In early atherosclerosis, compensatory enlargement of both the outer wall of the vessel as well as the lumen, termed compensatory enlargement or positive remodeling, occurs before luminal narrowing. METHODS One hundred seventy-nine participants in the MESA (Multi-Ethnic Study of Atherosclerosis) trial were evaluated using black-blood coronary wall MRI. Coronary cross-sectional area (vessel size), lumen area, and mean wall thickness of the proximal coronary arteries were measured. RESULTS Men had a greater vessel size, lumen area, and mean wall thickness than women (38.3 +/- 11.3 mm2 vs. 32.6 +/- 9.4 mm2, 6.7 +/- 3.2 mm2 vs. 5.3 +/- 2.4 mm2, and 2.0 +/- 0.3 mm vs. 1.9 +/- 0.3 mm, respectively, p < 0.05). No significant coronary artery narrowing was present by magnetic resonance angiography. Overall, coronary vessel size increased 25.9 mm2 per millimeter increase in coronary wall thickness, whereas lumen area increased only slightly at 3.1 mm2 for every millimeter increase in wall thickness (difference in slopes, p < 0.0001). Adjusting for age and sex, participants with an Agatston score >0 were more likely to have wall thickness >2.0 mm (odds ratio: 2.0, 95% confidence interval: 1.01 to 3.84). CONCLUSIONS Coronary wall MRI detected positive arterial remodeling in asymptomatic men and women with subclinical atherosclerosis.