13 research outputs found
Variations in atherosclerosis and remodeling patterns in aorta and carotids
Atherosclerosis is a progressive disease that causes vascular remodeling that can be positive or negative. The evolution of arterial wall thickening and changes in lumen size under current "standard of care" in different arterial beds is unclear. The purpose of this study was to examine arterial remodeling and progression/regression of atherosclerosis in aorta and carotid arteries of individuals at risk for atherosclerosis normalized over a 1-year period. In this study, 28 patients underwent at least 2 black-blood in vivo cardiovascular magnetic resonance (CMR) scans of aorta and carotids over a one-year period (Mean 17.8 ± 7.5 months). Clinical risk profiles for atherosclerosis and medications were documented and patients were followed by their referring physicians under current "standard of care" guidelines. Carotid and aortic wall lumen areas were matched across the time-points from cross-sectional images. The wall area increased by 8.67%, 10.64%, and 13.24% per year (carotid artery, thoracic aorta and abdominal aorta respectively, p < 0.001). The lumen area of the abdominal aorta increased by 4.97% per year (p = 0.002), but the carotid artery and thoracic aorta lumen areas did not change significantly. The use of statin therapy did not change the rate of increase of wall area of carotid artery, thoracic and abdominal aorta, but decreased the rate of change of lumen area of carotid artery (-3.08 ± 11.34 vs. 0.19 ± 12.91 p < 0.05). Results of this study of multiple vascular beds indicated that different vascular locations exhibited varying progression of atherosclerosis and remodeling as monitored by CMR
Solution Geochemistry of the Water of Limestone Terrains
Limestone groundwater flows mainly in openings it has solutionally enlarged, thus an understanding of the water\u27s state of saturation relative to calcite (the principal mineral component of limestone) is fundamental to an understanding of the nature and evolution of the limestone aquifer. This study investigated the Mammoth Cave-Sinkhole Plain (MCSP) and Cave Hollow (CH) aquifers in Kentucky, both in Missippian limestones.
Both aquifers were always undersaturated with calcite. Except for completely ventilated vadose flows (usually) and some vadose seepage (occasionally), all recharges sampled (sinking streams, vadose flows, and vadose seepage) were also undersaturated. The lack of saturation in the MCSP aquifer was due to the introduction of carbon dioxide into the water in amounts difficult to explain by the carbon dioxide content of the above recharges. In both vadose flows and seepage, undersaturatlon tended to correlate directly with flow volume, and there was an inverse correlation between the amount of carbon dioxide and calcite saturation in most of the waters sampled. In vadose seepage this relationship was so strong as to suggest seasonal invariance of carbon dioxide content of the water prior to out gassing.
Results suggest solutional enlargement is greatest near recharge points in ventilated aquifers (CH) but the carbon dioxide introduction phenomenon (MCSP) allows solution over wide areas in unventilated aquifers
Cardiovascular magnetic resonance parameters of atherosclerotic plaque burden improve discrimination of prior major adverse cardiovascular events
<p>Abstract</p> <p>Aims</p> <p>Patients with prior major cardiovascular or cerebrovascular events (MACE) are more likely to have future recurrent events independent of traditional cardiovascular disease risk factors. The purpose of this study was to determine if patients with traditional risk factors and prior MACE had increased cardiovascular magnetic resonance (CMR) plaque burden measures compared to patients with risk factors but no prior events.</p> <p>Methods and Results</p> <p>Black blood carotid and thoracic aorta images were obtained from 195 patients using a rapid extended coverage turbo spin echo sequence. CMR measures of plaque burden were obtained by tracing lumen and outer vessel wall contours. Patients with prior MACE had significantly higher MR plaque burden (wall thickness, wall area and normalized wall index) in carotids and thoracic aorta compared to those without prior MACE (Wall thickness carotids: 1.03 ± 0.03 vs. 0.93± 0.03, p = 0.001; SD wall thickness carotids: 0.137 ± 0.0008 vs. 0.102 ± 0.0004, p < 0.001; wall thickness aorta: 1.63 ± 0.10 vs. 1.50 ± 0.04, p = 0.009; SD wall thickness aorta: 0.186 ± 0.035 vs. 0.139 ± 0.012, p = 0.009 respectively). Plaque burden (wall thickness) and plaque eccentricity (standard deviation of wall thickness) of carotid arteries were associated with prior MACE after adjustment for age, sex, and traditional risk factors. Area under ROC curve (AUC) for discriminating prior MACE improved by adding plaque eccentricity to models incorporating age, sex, and traditional CVD risk factors as model inputs (AUC = 0.79, p = 0.05).</p> <p>Conclusion</p> <p>A greater plaque burden and plaque eccentricity is prevalent among patients with prior MACE.</p
LIFETIME RISK ALGORITHM IDENTIFIES MORE PATIENTS WITH CAROTID AND FEMORAL PLAQUES THAN 10 YR OR 30 YR FRAMINGHAM RISK ALGORITHMS
Carotid Plaque Characterization, Stenosis, and Intima-Media Thickness According to Age and Gender in a Large Registry Cohort.
Carotid intima-media thickness (CIMT) is a well-established predictor of cardiovascular disease events. Not well described, however, is the prevalence of plaque and stenosis severity and how this varies according to extent of CIMT, age, and gender. We evaluated the extent of carotid plaque and stenosis severity according to CIMT, age, and gender in a large CIMT screening registry. We studied 9,347 women and 12,676 men (n = 22,023) who received carotid ultrasound scans. The presence and severity of both carotid plaque and stenosis was compared according to extent of CIMT (≥1 mm vs <1 mm), age, and gender using the chi-square test of proportions. Among those aged <45 to ≥80 years, the prevalence of CIMT ≥1 mm ranged from 0.13% to 29.3% in women and 0.6% to 40.1% in men, stenosis ≥50% from 0.1% to 14.9% in women and 0.1% to 13.2% in men, and mixed and/or soft plaque from 7.1% to 66.5% in women, and 9.2% to 65.8% in men (all p <0.001 across age groups). Even when CIMT levels were <1 mm, >30% of patients demonstrated mixed or soft plaque potentially prone to rupture. Of those with CIMT ≥1 mm, more than 70% had such mixed or soft plaque and more than 40% demonstrated stenoses of 30% or greater. In conclusion, we describe in a large CIMT registry study a substantial age-related increase in both men and women of increased CIMT, plaque presence, and severity, and stenosis. Even in those with normal CIMT, mixed or soft plaque was common, further demonstrating the value in assessing for plaque when doing carotid ultrasound
Variations in atherosclerosis and remodeling patterns in aorta and carotids
Abstract Background Atherosclerosis is a progressive disease that causes vascular remodeling that can be positive or negative. The evolution of arterial wall thickening and changes in lumen size under current "standard of care" in different arterial beds is unclear. The purpose of this study was to examine arterial remodeling and progression/regression of atherosclerosis in aorta and carotid arteries of individuals at risk for atherosclerosis normalized over a 1-year period. Methods In this study, 28 patients underwent at least 2 black-blood in vivo cardiovascular magnetic resonance (CMR) scans of aorta and carotids over a one-year period (Mean 17.8 ± 7.5 months). Clinical risk profiles for atherosclerosis and medications were documented and patients were followed by their referring physicians under current "standard of care" guidelines. Carotid and aortic wall lumen areas were matched across the time-points from cross-sectional images. Results The wall area increased by 8.67%, 10.64%, and 13.24% per year (carotid artery, thoracic aorta and abdominal aorta respectively, p Conclusions Results of this study of multiple vascular beds indicated that different vascular locations exhibited varying progression of atherosclerosis and remodeling as monitored by CMR.</p
Carotid Plaque Characterization, Stenosis, and Intima-Media Thickness According to Age and Gender in a Large Registry Cohort
Carotid intima-media thickness (CIMT) is a well-established predictor of cardiovascular disease events. Not well described, however, is the prevalence of plaque and stenosis severity and how this varies according to extent of CIMT, age, and gender. We evaluated the extent of carotid plaque and stenosis severity according to CIMT, age, and gender in a large CIMT screening registry. We studied 9,347 women and 12,676 men (n = 22,023) who received carotid ultrasound scans. The presence and severity of both carotid plaque and stenosis was compared according to extent of CIMT (≥1 mm vs <1 mm), age, and gender using the chi-square test of proportions. Among those aged <45 to ≥80 years, the prevalence of CIMT ≥1 mm ranged from 0.13% to 29.3% in women and 0.6% to 40.1% in men, stenosis ≥50% from 0.1% to 14.9% in women and 0.1% to 13.2% in men, and mixed and/or soft plaque from 7.1% to 66.5% in women, and 9.2% to 65.8% in men (all p <0.001 across age groups). Even when CIMT levels were <1 mm, >30% of patients demonstrated mixed or soft plaque potentially prone to rupture. Of those with CIMT ≥1 mm, more than 70% had such mixed or soft plaque and more than 40% demonstrated stenoses of 30% or greater. In conclusion, we describe in a large CIMT registry study a substantial age-related increase in both men and women of increased CIMT, plaque presence, and severity, and stenosis. Even in those with normal CIMT, mixed or soft plaque was common, further demonstrating the value in assessing for plaque when doing carotid ultrasound