Carotid Ultrasound Scan Research Articles

A comparison of ultrasound measurements to assess carotid atherosclerosis development in subjects with and without type 2 diabetes

BackgroundSubjects with type 2 diabetes are at an increased risk of vascular complications. The use of carotid ultrasound remains an attractive, non-invasive method to monitor atherosclerotic disease progression and/or response to treatment in patients with type 2 diabetes, with intima-media thickness routinely used as the gold standard to detect pathology. However, alternative measurements, such as plaque area or volume, may represent a potentially more powerful approach. Thus, the objective of this study was to compare the traditional intima-media thickness measurement against the novel total plaque volume measurement in analyzing carotid atherosclerosis development in individuals with type 2 diabetes.MethodsThe case-control study included 49 Oji-Cree adults with diabetes or impaired glucose tolerance, aged 21–69, and 49 sex- and age-matched normoglycemic subjects. At baseline, metabolic variables were measured, including body mass index, waist circumference, total cholesterol:high density lipoprotein ratio, plasma triglycerides, plasma glucose, and serum insulin. Carotid ultrasound measurements, 7 years later, assessed carotid arterial intima-media thickness and total plaque volume.ResultsAt baseline, the two groups were well matched for smoking habits, hypertension, body mass index, and waist circumference. Differences were noted in baseline measurements of total cholesterol:high density lipoprotein (P = 0.0006), plasma triglycerides (P < 0.0001) and fasting glucose (P < 0.0001). After seven years, carotid ultrasound scans revealed that total plaque volume measurements (P = 0.037), but not intima-media thickness measurements, were higher in subjects with diabetes/impaired glucose tolerance compared to the normoglycemic controls. Correlation between intima-media thickness and total plaque volume was moderate. Based on our study findings, to achieve power levels >0.70 when comparing intima-media thickness measurements for diabetics versus non-diabetics, thousands of study subjects are required. For comparing total plaque volume measurements, only hundreds of study subjects are required.ConclusionThe development of atherosclerotic plaque is greater in subjects with diabetes/impaired glucose tolerance. Total plaque volume appears to capture the atherosclerotic disease burden more effectively in subjects with type 2 diabetes, and would be an appropriate outcome measure for studies aimed at changing the diabetic milieu.

Cardiac structural and functional changes during long-term antihypertensive treatment with lacidipine and atenolol in the European Lacidipine Study on Atherosclerosis (ELSA)

To evaluate and correlate the effects of long-term antihypertensive treatment on left ventricular (LV) mass and carotid structural changes in a large group of essential hypertensive patients, participating in the European Lacidipine Study on Atherosclerosis (ELSA). In four (Brescia, Glasgow, Naples and Pisa) of 23 centres participating in the ELSA study, an echocardiographic examination was performed at baseline and repeated, until the end of the 4-year study, in essential hypertensive patients, followed-up for carotid quantitative ultrasound examination of intima-media thickness (IMT), after random allocation to treatment with either lacidipine or atenolol (and added hydrochlorothiazide, as required for control of blood pressure). M-mode, two-dimensional guided echocardiography was used to measure left ventricular (LV) wall thickness and dimensions, from which LV mass was calculated, using an anatomically validated formula (Penn Convention) and indexed to body surface area (left ventricular mass index, LVMI). The echocardiographic tracings were blindly evaluated in a single reading centre (Brescia). Bilateral IMT was measured at the site of common carotid and bifurcation far walls (CBMmax). At baseline, cardiac and carotid ultrasound scans were available in 278 patients (mean age 54 +/- 7 years, 57% males, 22% obese). A significant correlation was observed between baseline LVMI and CBMmax (r = 0.22, P < 0.001), independent of age. In multivariate analysis, CBMmax and mean 24-h pulse pressure were most strongly associated with baseline LVMI. A significant reduction in LVMI was observed both during lacidipine (n = 96) (-12.5% reduction) and atenolol (n = 78) (-13.9% reduction) treatments (up to 4 years) (P < 0.001 for both, without significant differences between treatments). Changes in LVMI were not related to changes in carotid wall thickness. In multivariate analysis, baseline LV mass and mean 24-h systolic blood pressure changes were significantly associated with changes in LV mass. In this large, long-term controlled study, antihypertensive treatment with atenolol or lacidipine was accompanied by a similar and significant decrease in LV mass. Treatment-induced changes in LV mass were related to baseline LV mass and changes in 24-h mean systolic blood pressure, without any correlation with changes in carotid structure. In the whole ELSA population, carotid IMT changes have been shown to be unrelated to blood pressure reduction, but significantly influenced by the type of antihypertensive treatment.

Endovascular treatment of an internal carotid artery thrombus using reversal of flow: A case report

A case of a symptomatic free-floating thrombus of the internal carotid artery is described. A 51-year-old woman presented with a transient ischemic attack and was placed on anticoagulation after diagnosis with angiography. After medical therapy failed, she underwent suction embolectomy using reversal of flow with the Parodi Anti-Embolism System. Balloon angioplasty was performed, and a stent was placed. The patient tolerated the procedure well. A follow-up carotid ultrasound scan showed resolution of the thrombus.

Intracranial arterial dolichoectasia is associated with enlarged descending thoracic aorta

Intracranial arterial dolichoectasia (IADE) is defined as an increase in length and diameter of the intracranial arteries and is present in 12% of stroke patients. The pathophysiology is unknown; some data suggest that IADE is not merely a complication of atherosclerosis, but a distinct arteriopathy characterized by loss of elastic tissue in the media. To investigate the relationship between IADE and transesophageal echocardiography (TEE) variables such as ascending and descending thoracic aorta diameters. The sample included 154 patients with brain infarction (BI) and with measurement of the descending thoracic aorta on TEE. IADE was diagnosed by consensus between two neurologists. Information on demographic characteristics and risk factors was collected using a structured questionnaire, and a carotid ultrasound scan was performed. IADE was identified in 23 of the 154 stroke patients (15%). The mean diameter (+/-SD) of the descending thoracic aorta was significantly higher in the IADE(+) than in the 131 IADE(-) stroke patients (mean +/- SD 26.6 +/- 3.6 vs 24.8 +/- 2.7 mm). The proportion of IADE increased regularly with the quartiles of descending thoracic aorta diameter: 5%, 13%, 18%, and 24% (test of linear trend, p = 0.02). The adjusted OR (95% CI) of IADE associated with a 1 mm increase in descending thoracic aorta diameter was 1.22 (95% CI, 1.02 to 1.45). Patients with intracranial arterial dolichoectasia (IADE) have larger descending thoracic aorta diameters than non-IADE patients, suggesting that the underlying process causing IADE also affects the descending thoracic aorta.

Changes in cardiovascular risk factors during the perimenopause and postmenopause and carotid artery atherosclerosis in healthy women.

The objectives of this study were to describe the changes in cardiovascular risk factors during the perimenopausal and early postmenopausal years and correlate those changes in risk factors with carotid intimal-medial thickness (IMT) and plaque index measured 5 to 8 years after menopause. Participants were women (n=372) from Allegheny County, Pennsylvania, enrolled in the Healthy Women Study who had been postmenopausal for at least 5 years. Risk factor changes were measured during the perimenopause, ie, between the premenopausal and first year postmenopausal examinations, and during the early postmenopause, ie, between the first and fifth year postmenopausal examinations. Carotid ultrasound scans measured IMT and plaque at examinations 5 to 8 years after menopause among 314 of the women. Increases in LDL cholesterol and triglycerides and declines in HDL cholesterol were greater during perimenopause than postmenopause, whereas increases in blood pressure and fasting glucose levels were greater during postmenopause. Premenopausal systolic and pulse pressure, LDL and HDL cholesterol, triglycerides, and body mass index predicted IMT and plaque. Only the change in pulse pressure between premenopausal and first year postmenopausal examinations was related to both IMT and plaque. Absolute risk for cardiovascular disease increases substantially in midlife, with a particularly adverse effect on lipid metabolism at the menopause. Premenopausal levels of risk factors are adequate to identify which women should be targeted for intervention.

Carotid Arterial Ultrasound Scan Imaging: A Direct Approach to Stenosis Measurement

Carotid Arterial Ultrasound Scan Imaging: A Direct Approach to Stenosis Measurement

Carotid arterial ultrasound scan imaging: A direct approach to stenosis measurement

Purpose: Management decisions regarding carotid artery disease are critically dependent on stenosis but have been made difficult because of conflicting methods used to determine such stenosis. The increasing use of duplex ultrasound scanning has conventionally depended on Doppler velocity measurement, an indirect method for calculating carotid stenosis. Recent technical advances have improved the quality of B-mode/color-flow ultrasound scan imaging (USI). We tested prospectively whether USI was clinically effective as the primary criterion for estimating carotid stenosis. Methods: Transverse and longitudinal USI, Doppler velocity, and arteriography data were obtained sequentially and independently for 713 carotid bifurcations. The internal carotid artery (ICA) residual lumen, the local outer diameter at the stenotic site, and the diameter distal to the bulb were measured in a representative USI longitudinal section. The peak systolic velocity and the end diastolic velocity (EDV) were measured at the stenosis. Local stenosis as determined with USI was compared with the x-ray arteriographic clinical radiology interpretation (XRI). As the primary method, radiologists compared the residual lumen with the distal ICA diameter, as recommended by the North American Symptomatic Carotid Endarterectomy Trial and the Asymptomatic Carotid Atherosclerosis Study. Analysis was by means of the USI positive predictive value (PPV) and negative predictive value (NPV) of the XRI findings, with the assumption that 80%, 70%, and 60% local stenosis with USI related to 70%, 60%, and 50% stenosis with XRI, respectively. Results: All 56 ICA occlusions as determined with USI were confirmed with XRI. When the USI showed 80% to 99% stenosis, the PPV of the XRI showing 70% to 99% stenosis was 94% (116/123). Two ICAs that were shown to be severely diseased with USI appeared to be occluded with XRI. For <50% stenosis shown with USI, the prediction of <50% stenosis shown with XRI was 94% (253/269). For borderline stenosis in the 50% to 79% range with USI, the addition of velocity criteria to USI data improved both the PPV and the NPV. In the range of 70% to 79% stenosis with USI, the PPV improved from 82% (76/93) to 91% (53/58) for the subgroup with an EDV of more than 80 cm/s. For the range of 60% to 69% stenosis with USI, the PPV improved from 75% (71/95) to 95% (21/22) for the subgroup with an EDV of more than 80 cm/s. In the range of 50% to 59% stenosis with USI, the NPV improved from 69% (53/77) to 93% (14/15) for the subset with a peak systolic velocity of less than 100 cm/s. Conclusion: On the basis of the USI data alone, a prediction of arteriographic findings was possible at the 95% level for occlusion and severe stenosis and for ruling out hemodynamically significant stenosis. The addition of velocity data improved prediction in borderline degrees of stenosis. USI was effective for quantifying clinically significant degrees of stenosis. (J Vasc Surg 1999;29:838-44.)