Atheroma Thickness Research Articles

A comparison of thoracoabdominal aortic aneurysms open repair in patients with or without “shaggy aorta”

ObjectiveIn the field of thoracoabdominal aortic aneurysm (TAAA) open surgical repair (OSR), some preoperative characteristics are established risk factors for adverse outcomes, whereas others are supposed to be relevant, but their role still need to be defined; among them, the presence of “shaggy aorta” (SA), an extensive and irregular atheroma within the aorta. The aim of this study is to report the results of a single-center large cohort of patients treated with OSR for TAAA with SA, comparing the outcomes with patients affected by TAAA without SA, and analyzing the impact of the scores for SA on the outcomes. MethodsAll consecutive patients receiving OSR for TAAA between 2012 and 2021 were retrospectively analyzed. Clinical data from patients with degenerative TAAA were included and analyzed for preoperative characteristics and postoperative outcomes; patients with ruptured TAAA, and patients with aortic dissection were excluded from the analysis. Patients with degenerative aortic aneurysm, thrombus measurement in non-aneurysmal aortic segments (≤40 mm), atheroma thickness ≥5 mm, and finger-like thrombus projection were included in the SA group, whereas the others were included in the non-shaggy aorta group (NSA group). The SA group and NSA group were compared using a propensity-matched comparison. Preoperative computed tomography scans of patients in the SA group were also stratified according to SA grading scores. ResultsA total of 58 patients with SA were identified (male, n = 43 [74.1%], mean age 70.1 ± 7.8 years) among 497 patients with TAAA treated with open surgical repair. After propensity matching, there were 57 patients in the SA group and 57 in the NSA group with correction of all differences in baseline characteristics. Patients in the SA group presented significantly higher in-hospital mortality (SA group, 14.0% vs NSA group, 3.5%; P = .047), postoperative acute renal failure (Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease [RIFLE], 3-5) (SA group, 21.1% vs NSA group, 5.3%; P = .013), and postoperative embolization (SA group, 28.1% vs NSA group, 8.8%; P = .008). Spinal cord ischemia and stroke rate were not significantly influenced by the presence of SA. In the SA group, 16 patients (27.6%) with end-organ embolization were compared with 42 patients (72.4%) without a documented embolization considering the grade of aortic “shagginess” and no significant difference was identified (P = .546). ConclusionsDespite a better knowledge of the SA disease, new classifications, and intraoperative adjuncts, TAAA patients with SA treated with OSR have worse postoperative outcomes if compared with patients without SA. The presence of SA is a risk factor itself, whereas the grade of “shagginess” seems not to impact on postoperative outcomes.

Relationship between tissue characteristics and mechanical properties of coronary plaques: a comparison between integrated backscatter intravascular ultrasound (IVUS) and speckle-tracking IVUS.

High-risk coronary plaques have certain morphological characteristics. Thus, comprehensive assessment is needed for the risk stratification of plaques in patients with coronary artery disease. Integrated backscatter intravascular ultrasound (IB-IVUS) has been used successfully used to evaluate the tissue characteristics of coronary plaques; however, the mechanical properties of plaques have been rarely assessed. Therefore, we developed Speckle-tracking IVUS (ST-IVUS) to evaluate the mechanical properties of coronary plaque. This study aimed to evaluate the relation between the tissue characteristics of coronary plaques using IB-IVUS and their mechanical properties using ST-IVUS. We evaluated 95 non-targeted plaques in 95 patients undergoing elective percutaneous coronary intervention to the left anterior descending artery. We set regions of interest (ROIs) in the cross-sectional images of coronary plaques where we divided 120 degree plaques into four quadrants (every 30 degrees), with the center at the area of maximum atheroma thickness. We measured relative calcification area (%CA, relative fibrous area (%FI) and relative lipid pool area (%LP) in a total of 380 ROIs. In ST-IVUS analysis, we measured strain in the circumferential direction of the lumen area (LA strain: %), the external elastic membrane area strain (EEM strain: %), and strain in the radial direction (radial strain: %). On global cross-sectional area IB-IVUS analysis, the %CA was 1.2 ± 1.2%; the %FI was 49.0 ± 15.9%, and the %LP was 49.7 ± 16.5%. In ST-IVUS analysis, the LA strain was 0.67 ± 0.43%; the EEM strain was 0.49 ± 0.33%, and the radial strain was 2.02 ± 1.66%. On regional analysis, the %LP was not associated with the LA strain (r = - 0.002 p = 0.97), the EEM strain (r = - 0.05 p = 0.35), or with the radial strain (r = - 0.04 p = 0.45). These trends were seen between the %FI and the LA strain (r = 0.02 p = 0.74), the %FI and the EEM strain (r = 0.05 p = 0.35), and the %FI and the radial strain (r = 0.04 p = 0.50). A significant correlation was only observed between the %CA and the LA strain (r = - 0.15 p = 0.0038). Our findings indicate that the associations between mechanical properties and tissue characteristics lacked statistical significance, more often than not, and that it is necessary to evaluate the mechanical properties as well as plaque characteristics for risk stratification of coronary plaques.

A Comparison of Thoracoabdominal Aortic Aneurysms Open Repair in Patients With or Without “Shaggy Aorta”

Shaggy aorta (SA) syndrome is an independent risk factor for mortality, spinal cord ischemia, and acute renal failure in patients submitted to open thoracoabdominal aortic aneurysm (TAAA) repair. The aim of this paper is to report the results of a single-center large cohort of patients treated with open surgical repair (OSR) for TAAA with SA, comparing the outcomes with patients affected by TAAA without SA, and analyzing the impact of the actual scores for SA on the outcomes. All consecutive patients receiving OSR for TAAA between 2012 and 2021 were retrospectively analyzed. Clinical data from patients with degenerative TAAA were included and analyzed for preoperative characteristics and postoperative outcomes; patients with ruptured TAAA and patients with aortic dissection were excluded from the analysis. Patients with degenerative aortic aneurysm, thrombus measurement in nonaneurysmal aortic segments (≤40 mm), atheroma thickness ≥5 mm, and finger-like thrombus projection were included in the “SA group,” whereas the others were included in the “non-shaggy aorta group” (NSA group). The SA group and NSA group were compared using a propensity-matched comparison. Preoperative computed tomography scans of patients in the SA group were also classified according to the actual SA grading scores. A total of 58 patients with SA were identified (male 43 [74.1%], mean age 70.1 ± 7.8 years). After propensity matching, there were 48 patients in the SA group and 48 in the NSA group with correction of all differences in baseline characteristics. Patients in the SA group presented significantly higher in-hospital mortality (SA group: 10.4% vs NSA group: 2.1%, P < .001), postoperative acute renal failure (RIFLE 4-5) (SA group: 16.7% vs NSA group: 0%, P < .002), and embolization rate (SA group: 25.0% vs NSA group: 8.3%, P < .02). Spinal cord ischemia and stroke rate were not significantly influenced by the presence of SA. In the SA group, 16 (27.6%) patients with end-organ embolization were compared with 42 (72.4%) patients without a documented embolization considering the grade of aortic “shagginess,” and no significant difference was identified (P = .0546). Despite several intraoperative adjuncts, TAAA patients with SA treated with OSR still have worse postoperative outcomes if compared with “non-shaggy” patients. The presence of SA is a risk factor itself, whereas the grade of “shagginess” seems not to impact on postoperative outcomes.

Relationship between carotid atheroma thickness and albuminuria in diabetic patients

&nbsp; Our aim in this study to assess the efficacy of albuminuria in type 2 diabetes mellitus to be as predictor and independent marker of atherosclerosis by measurement of carotid intimal-medial thickness (CIMT)&nbsp; by high frequency ultrasonography. One hundred twenty participants in this study, 45 as a control healthy person and the others 75 patients with type 2 diabetes mellitus were included in this study. We divided into three groups: group 1 which is the control group, and group 2 those patients who are the diabetic without albuminuria, and group 3 are the diabetic patients with albuminuria. The intimal-medial thickness (IMT) was measured by high frequency ultrasonography. Other laboratory investigations were measured like HbA1c, fasting blood sugar, lipid profile. The intimal-medial thickness (IMT) was found higher in group 3 than group 1 and group 2 (P value &lt; 0.05). In conclusion, there is a significant association between micro- albuminuria and IMT as a marker of atherosclerosis in type 2 diabetes mellitus.

Impact of shaggy aorta on outcomes of open thoracoabdominal aortic aneurysm repair

BackgroundThe aim of this study was to evaluate the impact of diffuse aortic atherosclerosis–related thrombosis, or “shaggy aorta” on the outcomes of open thoracoabdominal aortic aneurysm repair (TAAA). MethodsFrom October 1999 to March 2018, 251 patients underwent open TAAA repair using segmental-staged aortic clamping. Twenty-eight patients (11.2%) received emergent or urgent operations. Patients were classified into 3 groups: dissection aneurysm (139 patients, 55.4%), degenerative aneurysm without shaggy aorta (76 patients, 30.3%), and degenerative aneurysm with shaggy aorta (36 patients, 14.3%). Shaggy aorta was assessed using enhanced computed tomography and defined as patients with atheroma thickness ≥5 mm with irregular atheroma surface. Mean follow-up was 4.3 ± 4.1 years. ResultsOperative mortality was 8% (20 patients) and spinal cord injury occurred in 25 patients (10.0%), 16 of whom (6.4%) had permanent neurologic dysfunction. Operative mortality was significantly worse in patients with shaggy aorta (dissection: 2.2%, non-shaggy: 6.6%, and shaggy: 33.3%, P < .001) and shaggy aorta was a significant risk factor for spinal cord injury (dissection: 7.2%, non-shaggy: 6.6%, and shaggy: 27.8%, P < .003). Multivariable analysis demonstrated that shaggy aorta was a significant risk factor for composite outcome consisted of operative mortality, spinal cord injury, and acute renal failure (odds ratio, 4.78; 95% confidence interval, 1.91-12.3, P < .001). ConclusionsPreoperative enhanced computed tomography assessment of shaggy aorta could predict high-risk patients for open TAAA repair.

Abstract WP216: Stroke Recurrence in Patients With Cryptogenic Stroke

Background &amp; Purpose: In cryptogenic stroke or transient ischemic attack (TIA) patients, aortic arch atheroma or patent foramen ovale (PFO) evaluated by using transesophageal echocardiography (TEE) is well known as possible embolic source. These findings were sometimes associated with stroke recurrence. We investigated predictive factors for stroke recurrence in patients with cryptogenic stroke. Methods: From February 2008 to December 2013, among 1832 consecutive stroke or TIA patients, 315 patients (male, 57.8%; age, 73.3±10.9) who were admitted within 7 days after the symptom onset without both atrial fibrillation and significant stenosis (50% or more in diameter) in the cerebral arteries underwent TEE for evaluating embolic sources; embolism was the probable etiological mechanism for their event. Patients with malignancy, cerebral arterial dissection, or infarcts in the perforating artery territory were excluded. We observed stroke recurrence during one year and investigated predictive factors for stroke recurrence. Results: In TEE, spontaneous echo contrast in the left atrium, aortic arch atheroma of 4.0 mm or more in thickness (mean, 4.65±2.06 mm), PFO, and pulmonary arteriovenous fistula were observed in 24 (7.6%), 223 (70.3%), 26 (8.2%), and 20 (6.3%) patients, respectively. Stroke recurrence was observed in 39 (12.4%) patients. Aortic arch atheroma of 4.0 mm or more, male, and prior hemorrhagic stroke were more frequent, and the initial diastolic blood pressure (DBP) and HbA1c were higher in patients with than without stroke recurrence. On the multivariate analysis using those factors and age, aortic arch atheroma (OR 3.73, 95%CI 1.46–11.7) and the initial DBP (OR 1.03, 95%CI 1.00–1.05) were positive predictors for a stroke recurrence. With regard to the operating characteristic curve analysis, the most accurate cut off values for a stroke recurrence were 4.1mm (AUC 0.59) in aortic arch atheroma thickness and 91mmHg in DBP (AUC 0.58). Conclusions: In acute cryptogenic stroke, aortic arch atheroma was observed frequently. Aortic arch atheroma and DBP were significantly associated with one-year stroke recurrence. TEE was required for evaluating aortic arch atheroma in patients with cryptogenic stroke

Contrast Ultrasound Imaging of the Aorta Does Not Affect Progression of Atherosclerosis or Cardiovascular Biomarkers in ApoE-/- Mice.

Ultrasound contrast agents (UCAs) enhance cardiovascular ultrasound imaging. Adverse biological effects have occurred after administration of UCAs, and more research is needed for a comprehensive understanding of the risks involved. We used the ApoE(-/-) mouse model of atherosclerosis to characterize the effects of ultrasound and UCAs on atherosclerosis and plasma biomarkers. Male ApoE(-/-) mice (8 weeks old; n = 24) were intravenously infused with a UCA (2 × 10(10) Definity microbubbles per hour; Lantheus Medical Imaging, North Billerica, MA) and exposed to 2.8-MHz center frequency ultrasound (10 Hz pulse repetition frequency, 1.4 microseconds pulse duration, 2 minutes exposure duration, and 2 sites) at 1 of 3 derated peak rarefactional pressure amplitudes (0, 1.9, or 3.8 MPa), and then consumed either a chow or Western diet for 4 weeks (n = 4 per group). Blood plasma samples were collected before ultrasound exposure and at 2 and 4 weeks after exposure and assayed for total cholesterol and von Willebrand Factor (vWF). A pathologist measured atheroma thickness in formalin-fixed, hematoxylin-eosin-stained transverse aorta sections and scored them for severity of atherosclerosis. Plasma total cholesterol initially averaged 286 mg/dL in the Western diet group and increased to 861 mg/dL after 4 weeks on the diet (P < .0001). Total cholesterol did not increase significantly in the chow diet group. Plasma vWF increased after 2 weeks on the Western diet (P < .0001). Atheroma thickness was greater in animals consuming the Western diet than in chow-fed animals (P < .05). Ultrasound had no significant effect on plasma total cholesterol, plasma vWF, or atheroma thickness. Contrast ultrasound did not increase the severity of atherosclerosis or alter cardiovascular biomarkers in the ApoE(-/-) mouse model.

Contrast ultrasound imaging of the aorta does not affect progression of atherosclerosis in ApoE−/− mice

Ultrasound Contrast Agents (UCAs) are used clinically to enhance ultrasound imaging of the cardiovascular system. Adverse biological effects have been noted after administration of UCAs, and more research is needed for an understanding of the biological effects of UCAs. Male ApoE−/− mice (8 weeks old, n=38) were intravenously infused with the Definity® UCA (2×1010 UCA/hr) and either exposed to 2.8‐MHz 10‐Hz PRF 1.4‐μs PD 2‐min ED 1.4‐MPa PRPA ultrasound or sham exposed, and then consumed either a chow or Western diet for either 4 or 8 weeks after ultrasound exposure (n=4–5 per group). Plasma total cholesterol was greater in the Western diet group than the chow group for all timepoints after baseline (p&lt;0.0001). Plasma von Willebrand Factor (vWF), a biomarker of endothelial function, was elevated in Western diet animals compared to chow animals (p&lt;0.05). Atheroma thickness was greater in animals consuming the Western diet than in chow‐fed animals (p&lt;0.001), and in animals euthanized after 8 weeks than after 4 weeks (p&lt;0.005). Ultrasound did not affect plasma total cholesterol levels, plasma vWF or atheroma thickness. [Supported by NIH R37EB002641]

Optimization of a Low Magnesium, Cholesterol-Containing Diet for the Development of Atherosclerosis in Rabbits

The cholesterol-fed rabbit is useful for atherosclerosis research. We describe development of a low-magnesium (Mg) cholesterol-containing diet to accelerate atherosclerosis in this model. Male New Zealand White rabbits were fed either chow or one of four atherogenic diets: 1% cholesterol 10% fat 0.11% Mg, 1% cholesterol 10% fat 0.40% Mg, 2% cholesterol 20% fat 0.11% Mg, or 2% cholesterol 20% fat 0.40% Mg. While feed intake decreased in cholesterol-fed rabbits, they were able to maintain their body weights. Rabbits consuming cholesterol experienced profound hypercholesterolemia and tissue lipid accumulation, with plasma cholesterol levels above 1500 mg/dl for all groups at the completion of the study. Liver and spleen lipid content and liver cholesterol content also increased. Aortic arch atheroma thickness was greatest in 1% cholesterol 10% fat 0.11% Mg animals. Tissue Mg levels decreased in cholesterol-fed animals compared to chow-fed controls, despite equal or greater serum Mg levels. Our results indicate that the 1% cholesterol 10% fat 0.11% Mg diet was optimal at promoting hypercholesterolemia and atherosclerosis while minimizing health complications for the animals. The low Mg cholesterol diet will be useful to other biomedical researchers interested in utilizing the rabbit for cardiovascular disease research.

Contrast Ultrasound Imaging of the Aorta Alters Vascular Morphology and Circulating von Willebrand Factor in Hypercholesterolemic Rabbits

Ultrasound contrast agents (UCAs) are intravenously infused microbubbles that add definition to ultrasonic images. Ultrasound contrast agents continue to show clinical promise in cardiovascular imaging, but their biological effects are not known with confidence. We used a cholesterol-fed rabbit model to evaluate these effects when used in conjunction with ultrasound (US) to image the descending aorta. Male New Zealand White rabbits (n = 41) were weaned onto an atherogenic diet containing 1% cholesterol, 10% fat, and 0.11% magnesium. At 21 days, rabbits were exposed to contrast US at 1 of 4 pressure levels using either the UCA Definity (Lantheus Medical Imaging, Inc, North Billerica, MA) or a saline control (n = 5 per group). Blood samples were collected and analyzed for lipids and von Willebrand factor (vWF), a marker of endothelial function. Animals were euthanized at 42 days, and tissues were collected for histologic analysis. After adjustment for pre-exposure vWF, high-level US (in situ [at the aorta] peak rarefactional pressure of 1.4 or 2.1 MPa) resulted in significantly lower vWF 1 hour post exposure (P = .0127; P(adj) < .0762). This difference disappeared within 24 hours. Atheroma thickness in the descending aorta was lower in animals receiving the UCA compared to animals receiving saline. Contrast US affected the descending aorta, as evidenced by two separate outcome measures. These results may be a first step in elucidating a previously unknown biological effect of UCAs. Further research is warranted to characterize the effects of this procedure.

Contrast ultrasound imaging of the aorta alters vascular morphology and circulating von Willebrand Factor in hypercholesterolemic rabbits

Ultrasound contrast agents (UCAs) are intravenously infused microbubbles that add definition to ultrasonic images. UCAs hold clinical promise in diagnostic imaging of cardiovascular disease, but their biological effects are not known with confidence. We utilized a cholesterol‐fed rabbit model to evaluate these effects when used in conjunction with ultrasound to image the descending aorta. Male New Zealand White rabbits (n=41) were weaned onto an atherogenic diet containing 1% cholesterol, 10% fat and 0.11% magnesium. After 21 days, rabbits were exposed to contrast ultrasound at one of four pressure levels using either the UCA Definity or saline control (n=5 per group). Blood samples were collected and analyzed for lipids and von Willebrand Factor (vWF), a marker of endothelial function. Animals were euthanized at 42 days and tissues were collected for analysis. After adjustment for pre‐exposure vWF, high‐level ultrasound (2.3 or 3.5 MPa) resulted in significantly lower vWF one hour post‐exposure (p=0.017). This difference disappeared within 24 hours. Animals receiving UCA displayed reduced atheroma thickness in the descending aorta as compared to animals receiving saline, possibly due to ultrasonic disruption of the atheroma. Plaque disruption can lead to thrombosis and myocardial infarction. Further research is warranted to characterize the effects of this procedure. [Supported by NIH R37EB002641]

Common Carotid Artery Intima-media Thickness is not Increased but Distensibility is Reduced in Normotensive Patients with Type 2 Diabetes compared with Control Subjects

This study evaluated carotid artery parameters in normotensive patients with type 2 diabetes compared with non-diabetic control subjects. Using a high-resolution B-mode ultrasound scanner, common carotid artery intima-media thickness (IMT) and carotid tree atheroma thickness were measured in 82 patients with type 2 diabetes and 41 controls. The distensibility of the common carotid artery was calculated using the Reneman equation. Distensibility was significantly decreased and atheroma thickness was significantly increased in the diabetes group. There was no significant difference in IMT between the two groups. Stepwise linear regression analysis revealed an association between common carotid artery distensibility and post-ischaemic dilatation of the brachial artery (a measure of endothelial function), body mass index and diabetes duration in patients with type 2 diabetes. In conclusion, common carotid artery IMT in normotensive patients with type 2 diabetes is comparable to that of control subjects, whereas atheroma thickness is higher and arterial stiffness more pronounced in those with type 2 diabetes, indicating the existence of atherosclerotic changes in normotensive type 2 diabetes patients.

Comparing Multislice Electrocardiogram-gated Spiral Computerized Tomography and Transesophageal Echocardiography in Evaluating Aortic Atheroma in Patients with Acute Ischemic Stroke

The aim of this study was to compare transesophageal echocardiography (TEE) and cardiac-gated computerized tomography (CGCT) in detecting aortic atherosclerosis (AA). There is evidence that AA can be a source of embolic material causing ischemic stroke. TEE is a well-established tool for detecting cardiac sources of emboli in patients with stroke, but it has distinct limitations in the detection of AA. This was a prospective study of patients admitted with the diagnosis of ischemic stroke between February and November of 2000. Among this cohort are patients who underwent both TEE and CGCT for the evaluation of stroke cause. The CGCT studies were retrieved and interpreted by a radiologist with special expertise in chest tomography, and TEE studies were read by an echocardiographer with special expertise in reading and performing TEE. The interpreters were unaware of the results obtained by the other. The AA was estimated by measuring atheroma thickness in millimeters. The relations between the two tests were analyzed graphically using Bland-Altman, and Pollock plots. Results from Pearson (r), Spearman (r(s)), and intraclass correlation tests were also estimated. The aortic atheroma thickness in millimeters was compared between CGCT and TEE in 32 patients, who underwent both studies. The intraclass correlation was 0.93, with high correlation (r = 082, r(s) = 0.83). CGCT detected smaller AA more often, and provided more information about the shape of atheromatous plaques. CGCT is similar to TEE in detecting AA. CGCT may detect smaller atheromas and be better in defining atheroma morphology.

Intravascular Ultrasound in Cardiovascular Medicine

Case presentation: A 38-year-old man underwent angiography 2 weeks after a non–ST-segment myocardial infarction. He was overweight and prehypertensive, with a blood pressure of 134/86 mm Hg. His biochemical parameters included low-density lipoprotein cholesterol (LDL-C) 127 mg/dL, high-density lipoprotein cholesterol (HDL-C) 38 mg/dL, and C-reactive protein (CRP) 3.2 mg/L. Angiography revealed mild disease throughout the coronary arteries and a hazy appearance that involved the proximal left anterior descending coronary artery. Intravascular ultrasound (IVUS) imaging revealed diffuse and extensive atherosclerosis with evidence of plaque rupture at multiple sites (Figure 1). In the presence of no significant luminal stenoses, the patient was treated medically with aspirin and low-dose statin therapy. Figure 1. Illustrative example of coronary angiography of the left anterior descending artery that appears to be free of irregularities, apart from a hazy appearance in the proximal segment. A representative cross-sectional tomographic image obtained by IVUS examination (top right) within the proximal segment (white arrow on angiogram) revealed substantial atheroma within the arterial wall. The bottom right segment illustrates a tomographic image of atheroma containing significant ulceration (5 o’clock) at the site of the gold arrow on the angiogram. The application of IVUS in this case highlights a number of important points with regard to the natural history of atherosclerosis and its modification by use of established medical therapies. The ability to image the entire arterial wall represents a significant advantage over coronary angiography. In the presence of minimal luminal stenoses, IVUS imaging in patients with coronary symptoms typically reveals extensive and diffuse atherosclerosis.1 Application of serial IVUS imaging in prospective clinical trials has enabled a greater understanding of the impact of antiatherosclerotic interventions on patients with established coronary artery disease (CAD). Ultrasonic coronary imaging has revealed essential details about the natural history of atherosclerosis. Atheroma formation begins at a …

Reproducibility of Transesophageal Echocardiography in Evaluating Aortic Atheroma in Stroke Patients

Although transesophageal echocardiography (TEE) is a well-established tool in delineating the cardiac and aortic sources of emboli in stroke patients, its reproducibility in detecting aortic atherosclerosis (AA) that may lead to stroke is not well documented. The aim of this study is to demonstrate the inter- and intra-observer agreement in diagnosing AA based on the TEE study. During the study period, 2 echocardiographers read 32 TEE studies performed on a group of stroke patients. The AA was estimated by measuring the largest atheroma thickness in millimeters (mm). The intra-observers and intraclass correlation coefficients (ICC) were 0.97 and 0.85, respectively, for the 2 TEE observers. The inter-rater ICC coefficient between TEE readers was 0.91. In conclusion, TEE detected AA and defined high proportions of the morphological characteristics of atheroma with good reproducibility among inter and intra-observers.

Atherosclerotic plaque distribution in the left anterior descending coronary artery as assessed by intravascular ultrasound

N studies have demonstrated asymmetric longitudinal and circumferential atherosclerotic plaque distribution along coronary arteries.1,2 In vivo data are limited and have primarily examined the left main artery bifurcation.3,4 In the proximal left anterior descending (LAD) artery, the wall opposite to the circumflex origin is a preferred site of plaque accumulation and is likely secondary to fluid dynamics near the bifurcation.5,6 It has been described that abnormally low or oscillatory shear forces at these sites contribute to atherogenesis.7 Assessment of plaque distribution in the proximal and mid-LAD artery has not been systematically described. Intravascular ultrasound (IVUS) is ideally suited to study distribution patterns of atherosclerotic plaque burden.8 Using a motorized pullback device that withdraws the IVUS catheter at a precisely controlled rate allows accurate mapping of the longitudinal and circumferential plaque patterns. In the present report, in vivo IVUS imaging was employed to examine plaque distribution in the LAD artery in relation to the first septal perforator in patients with mild coronary artery disease (CAD). • • • We analyzed IVUS studies in 50 patients with minimally obstructive CAD ( 50% angiographic diameter stenosis) of the native LAD artery. IVUS imaging was performed in standard fashion using either a 30-MHz, 3.2 or 2.9Fr catheter, or a 40MHz, 2.6Fr device (Cardiovascular Imaging Systems, Sunnyvale, California).9 The IVUS catheter was advanced over a guidewire to a position in the midto distal portion of the LAD artery after the administration of intracoronary nitroglycerin and anticoagulation with intravenous heparin. Motorized pullback at a rate of 0.5 mm/s was performed to the left main ostium with ultrasound images recorded on Super-VHS videotape. A long segment of the LAD artery pullback (20 to 60 seconds) was digitized from videotape into a 640 480-pixel image matrix with an 8-bit gray scale for each patient. The midpoint of the first septal perforator was identified on IVUS and angiographic images, and 7 serial cross-sectional slices were selected (midpoint of septal, 1, 2, and 3 mm proximally and distally) for a total of 350 cross sections (Figure 1). In each cross section, the vessel was divided into two 180° semicircles ipsilateral (septal) and contralateral (antiseptal) to the septal branch. In each semicircle, the external elastic membrane and lumen area were planimetered. Atheroma area (external elastic membrane lumen area) and maximum and minimum intimal thickness were calculated. All results are expressed as mean SD. Comparison of atheroma area and intimal thickness between the septal and antiseptal sides was performed using the paired, 2-tailed Student’s t test. A p value 0.05 was considered statistically significant. Fifty patients with mild coronary atherosclerotic disease of the LAD artery were included in the analysis. In the LAD artery segment adjacent to the first septal branch, mean atheroma area was substantially greater on the septal side than on the antiseptal side (3.44 1.6 vs 2.5 1.5 mm, p 0.0001). Mean intimal thickness on the septal side was also greater than the antiseptal side (1.03 0.48 vs 0.81 0.42 mm, p 0.0001; Table 1). This relation was evident for each of the 7 individual cross sections, and it was remarkably consistent throughout the cohort with 255 of 350 cross sections (73%; Figure 2). A distinctive pattern of longitudinal atheroma distribution was evident. At 3 mm proximal to the septal side, the plaque area on the septal side was much larger than that on the antiseptal side (3.69 1.8 vs 2.36 1.7 mm, p 0.0001). From a more distal position, the differences between septal plaque and the antiseptal side decreased progressively. At 3 mm distal to the septal side, the differences between the septal and antiseptal sides were the smallest (3.00 1.9 vs 2.45 1.5 mm, p 0.0086). Similar findings were noted for maximum atheroma thickness. At 3 mm proximal to the septal artery, the difference in plaque thickness between the septal and antiseptal sides was large (1.10 0.5 vs 0.76 0.4 mm, p 0.0001). The difference was smaller at a site 3 mm distal to the septal artery (0.93 0.5 vs 0.78 0.5 mm, p 0.0051). Figure 3 shows the plaque distribution (mean SD) adjacent to the first septal branch for the overall group. From The Cleveland Clinic Foundation, Cleveland, Ohio; and Yale University School of Medicine, New Haven, Connecticut. Dr. Nissen’s address is: The Cleveland Clinic Foundation, F 15, 9500 Euclid Avenue, Cleveland, Ohio 44195. E-mail: nissens@ccf.org. Manuscript received June 25, 2002; revised manuscript received and accepted October 11, 2002.

Palmaz Stent Deployment for Subclavian and Brachiocephalic Arterial Occlusive Disease

Palmaz stent deployment is a useful method for subclavian and brachiocephalic arterial occlusive disease. We evaluated restenosis or intimal thickening after Palmaz stent deployment for nine lesions of subclavian or brachiocephalic arterial occlusive disease focusing on stent diameter, atheroma thickness near the stent, and degree of coverage for the lesion. Follow up DSA and IVUS at 5-14 months (mean 9) after therapy showed no significant changes in the size or shape of the stent itself There were two lesions of thin in-stent intimal hyperplasia and five lesions of thick hyperplasia. There was no close relationship between intimal hyperplasia and stent diameter or atheroma size (relative thickness). There was some relationship between the degree of coverage of the lesion by the stent and degree of intimal hyperplasia, but to determine statistical significance, accumulation of a greater number of cases is necessary.