Comparison of lumens of intermediate coronary stenosis using 16-slice computed tomography versus intravascular ultrasound

We aimed to quantify ambiguous coronary stenosis using the minimal lumen area with 16-slice computed tomography compared with intravascular ultrasound. The sensitivity, specificity, and accuracy for significant lesion classification was 68%, 86%, and 78%, respectively. The correlation between intravascular ultrasound and CT minimal lumen area was r = 0.73 (p <0.001), and the 95% confidence interval for CT measurement was -72% to +56%.     

Evaluation of coronary atheroma by 64-slice multidetector computed tomography: Comparison with intravascular ultrasound and angiography

BACKGROUND:

Recent improvements in multidetector computed tomography (MDCT) with 64-slice scanners have allowed acquisition of a coronary study in 5 s to 6 s, with good temporal and spatial resolution. Previous studies have reported an underestimation of plaque burden by MDCT. Whether shorter scan times can allow correct assessment of plaque volume requires comparison with intravascular ultrasound (IVUS).

METHODS:

Patients (n=30) scheduled for coronary angiography also underwent MDCT and IVUS examinations within 96 h. MDCT examination was performed with a 64-slice scanner. Nitroglycerin was administered before all imaging procedures. MDCT, quantitative coronary angiography (QCA) and IVUS analyses were performed by observers blinded to other results. Plaque volumes were determined by MDCT and IVUS in one vessel, and maximum percentage diameter stenosis was identified in each coronary segment by MDCT and QCA.

RESULTS:

The mean (± SD) plaque volume was determined to be 179.1±78.9 mm³ by MDCT and 176.1±87.9 mm³ by IVUS. There was a strong positive correlation for plaque volume between MDCT and IVUS (r=0.84, P<0.0001). Percentage diameter stenosis assessed by MDCT and QCA also correlated well (r=0.88 per patient and r=0.87 per vessel, P<0.0001 for both). The maximum percentage diameter stenosis per vessel was 38.1±30.2% with MDCT and 34.1±27.6% with QCA. The sensitivity and specificity of MDCT in detecting stenoses above 50% per vessel were 100% and 91.0%, respectively.

CONCLUSIONS:

Plaque volumes measured by 64-slice MDCT and IVUS correlate well, without systematic underestimation. The sensitivity and specificity of MDCT to detect stenoses greater than 50% by QCA are excellent with the administration of nitroglycerin before imaging.     

Characterization of vulnerable nonstenotic plaque with 16-slice computed tomography compared with intravascular ultrasound

We compared 16-slice computed tomography with intravascular ultrasound in the detection of unstable component characteristics of nonstenotic plaque responsible for acute coronary syndrome. Computed tomography accurately assessed plaque eccentricity, calcification, and remodeling, and intraplaque hypodensity correlated with intravascular ultrasound echolucent area.     

Non-invasive assessment of plaque rupture by 64-slice multidetector computed tomography--comparison with intravascular ultrasound

BACKGROUND: Plaque rupture and secondary thrombus formation play key roles in the onset of acute coronary syndrome (ACS). Multidetector computed tomography (MDCT) allows the non-invasive assessment of coronary artery stenosis and plaque properties. In this study, we investigated whether 64-slice MDCT could non-invasively detect a plaque rupture in patients with de novo angina. METHODS AND RESULTS: The study population comprised 67 patients with de novo angina. All patients underwent contrast-enhanced 64-slice MDCT and intravascular ultrasound (IVUS). Patients were divided into a plaque rupture group (n=27) and a non-rupture group (n=40) based on the IVUS. The 64-slice MDCT revealed that the prevalence of an ulcer-like enhancement space (37% vs 5%, p<0.01), a ring-like sign (41% vs 18%, p=0.04), in the plaque rupture group was higher than those in the non-rupture group. Maximum plaque thickness (2.1+/-0.9 mm vs 1.6+/-1.0 mm, p=0.04), outer vessel area (17.6+/-4.9 mm2 vs 13.4+/-5.0 mm2, p<0.01), percentage plaque area (82.3+/-9.1% vs 73.4+/-15.7%, p=0.01), and remodeling index (1.11+/-0.18 vs 1.01+/-0.15, p=0.04) of the plaque rupture group were all significantly larger than those of the non-rupture group. CONCLUSIONS: The 64-slice MDCT can identify differences in lesion morphologies between ruptured plaques and non-ruptured plaques. From our results, the 64-slice MDCT might provide a useful tool for the non-invasive detection of plaque rupture.     

Characterization of coronary atherosclerotic plaques by multidetector computed tomography

Multidetector computed tomography (MDCT) provides 3-dimensional noninvasive visualization of the coronary arterial tree. We compared MDCT with intravascular ultrasound (IVUS) for assessment of severity of coronary artery stenosis and composition of atherosclerotic plaques in 40 patients (32 men; mean age 52 years, range 33 to 86) with documented coronary artery disease. Cross-sectional images obtained at 10-mm increments were assessed for percent decrease in luminal area. Atherosclerotic plaques were classified by IVUS as soft, fibrous, or calcified. On the matched multidetector computed tomograms, regions of interest of 1 to 3 mm in diameter were placed inside each plaque, and tissue contrast was measured in Hounsfield units. Obstructive coronary artery disease was found in 50 segments by IVUS and 57 segments by MDCT. Sensitivity for detecting obstruction >50% was 86.0% (95% confidence interval 72.6 to 93.7) and specificity was 90.2% (95% confidence interval 83.9 to 94.4). In total, 276 plaques were examined by IVUS and MDCT. There were 188 soft plaques (68.2%), 45 fibrous plaques (16.2%), and 43 calcified plaques (15.5%). Multidetector computed tomographic tissue contrast of soft, fibrous, and calcified plaques were 71.5 +/- 32.1, 116.3 +/- 35.7, and 383.3 +/- 186.1, respectively (p <0.001). Using a cut-off value of 185 HU, 273 of 276 plaques (99%) were correctly classified as calcified or noncalcified plaques. Using a cut-off value of 88 HU, 192 of 233 noncalcified plaques (82%) were correctly classified as fibrous or soft plaques. In conclusion, our data indicate that MDCT can provide important information concerning the composition of atherosclerotic plaques in addition to detecting luminal obstruction.     

Non-invasive assessment of plaque morphology and remodeling in mildly stenotic coronary segments: comparison of 16-slice computed tomography and intravascular ultrasound

BACKGROUND: Non-invasive identification and characterization of mildly stenotic atherosclerotic lesions is an increasingly important focus of coronary imaging. DESIGN: We examined the accuracy of multi (16)-slice computed tomography (MSCT) for imaging of these lesions in comparison with intravascular ultrasound (IVUS). MATERIALS: Mildly stenotic segments of the left coronary artery were identified by coronary angiography and analyzed using IVUS and contrast-enhanced MSCT. Independent reviewers evaluated the accuracy of MSCT for presence, composition and distribution of atherosclerotic plaque and remodeling response in comparison to IVUS using receiver operating characteristic (ROC) data analysis. RESULTS: Of 46 segments in 14 patients, diagnostic characterization by MSCT was possible in 37 (80.4%) segments. In these segments the accuracy of MSCT for identifying plaque presence, calcification, distribution and positive remodeling was consistently greater than 0.90 (reader 1) and 0.87 (reader 2). CONCLUSION: State-of-the-art MSCT can accurately identify mildly stenotic coronary atherosclerosis and provide an assessment of morphology and remodeling response.     

Comparison of 64-slice multidetector computed tomography with spectral analysis of intravascular ultrasound backscatter signals for characterizations of noncalcified coronary arterial plaques

In vivo identification of plaque composition may allow the detection of vulnerable plaques before rupture. However, the clinical relevance of multidetector computed tomography (MDCT) in characterizing coronary plaques is currently a subject of debate. We compared 64-slice MDCT with virtual histology to investigate the potential role of 64-slice MDCT in the differentiation of composition of noncalcified coronary plaques. Fifty-nine consecutive patients (stable/unstable angina 34/21) were enrolled. Mean computed tomographic (CT) density (Hounsfield units) of noncalcified coronary plaques (n = 80) was compared with a relative volume of each plaque component (fibrous, fibrofatty, calcium, and necrotic core) analyzed by virtual histology. Mean heart rate during MDCT was 58 +/- 9 beats/min. There was a negative correlation between mean CT density and the necrotic core (r = -0.539, p <0.001) and a positive correlation between mean CT density and the fibrotic tissue component (r = 0.571, p <0.001). Mean CT density of the plaques with a <10% necrotic core was significantly higher than that of a >or=10% necrotic core (93.1 +/- 37.5 vs 41.3 +/- 26.4 HU, p <0.001). However, overlapping of mean CT densities between plaques with a <10% necrotic core and those with a >or=10% necrotic core was found. In conclusion, mean CT density of noncalcified coronary plaques measured by 64-slice MDCT may depend on the relative volumes of the necrotic core and fibrotic component. Sixty-four-slice MDCT may have the potential for determining composition of noncalcified coronary plaques, which needs further studies for clinical application.     

Noninvasive tissue characterization of coronary arterial plaque by 16-slice computed tomography in acute coronary syndrome

Noninvasive characterization of coronary plaques is challenging for cardiologists. The authors' goal was to explore the clinical feasibility of newly developed 16-slice computed tomography (CT) in tissue characterization of coronary arterial plaques in patients with acute coronary syndrome. Sixteen patients with acute coronary syndrome underwent 16-slice CT (Aquillion, Toshiba) and coronary arteriography with intravascular ultrasound (IVUS) within 7 days. Twenty-three plaques were classified by IVUS according to plaque echogenicity: 6 soft plaques, 11 intermediate plaques, and 6 calcified plaques. Mean (+/- SD) CT numbers (Hounsfield units [HU]) of these 3 types of plaques were 50.6 +/-14.8 HU, 131 +/-21.0 HU, and 721 +/-231 HU, respectively. Sixteen-slice CT facilitates noninvasive tissue characterization of coronary arterial plaques.     

Relation of coronary plaque composition determined by 64-slice multidetector computed tomography in patients with suspected coronary heart disease

Sixty-four-slice multidetector row computed tomography is a noninvasive method of assessing coronary artery stenosis and plaque composition. The aim of this study was to clarify the relation between plaque composition and coronary heart disease. Three hundred sixty consecutive patients and 1,085 plaques were evaluated using 64-slice multidetector row computed tomography. On axial or cross-sectional multiplanar reconstruction images, 3 regions of interest were randomly selected within each plaque. Soft plaques and calcified plaques were defined as having computed tomographic densities <50 and >130 Hounsfield units, respectively. The association between coronary risk factors and plaque composition was analyzed. The number of plaques and the mean computed tomographic density of plaques were significantly higher in men than in women (p = 0.002 and p = 0.04, respectively). Coronary plaques were more frequent in patients with stroke, diabetes, hypertension, and dyslipidemia than in patients without these conditions (all p values <0.001). Calcified plaques were more frequent in patients with hypertension (p = 0.02), and patients with calcified plaques also had significantly lower low-density lipoprotein cholesterol levels (p <0.001). Soft plaques were more frequent in patients with dyslipidemia (p <0.001). Patients with soft plaques had significantly higher low-density lipoprotein cholesterol levels (p = 0.02) and lower high-density lipoprotein cholesterol levels (p <0.001) than those without soft plaques. In conclusion, 64-slice multidetector row computed tomography is a useful noninvasive method for quantifying coronary plaques.     

Detection of plaque rupture using 64-slice multidetector row computed tomography

The present case report describes a 37-year-old man who presented to the emergency room with symptoms of a myocardial infarction but no high-grade stenosis on conventional catheter angiography. Consecutive multidetector row computed tomography of the coronary arteries showed an intimal flap along a fibrous plaque formation in the left anterior descending artery. This finding was found to represent a plaque rupture, and the lesion was treated with an 18 mm stent. Multidetector row computed tomography helped to correctly position the stent by identifying the exact location of the rupture along the long plaque formation.     

Comparison of coronary minimal lumen area quantification by sixty-four-slice computed tomography versus intravascular ultrasound for intermediate stenosis

The present study assessed 64-slice computed tomographic accuracy to quantify minimal lumen area (MLA) and determine lesion severity in intermediate stenosis by angiography compared with intravascular ultrasound (IVUS). Sixty-four-slice computed tomography (CT) has been shown to be effective in coronary stenotic assessment by visual estimation compared with angiography. However, angiography is not an accurate gold standard for intermediate stenotic quantification compared with IVUS. Forty patients (54 lesions) with 30% to 70% coronary stenosis by angiography in a major coronary branch were included. All patients underwent quantitative angiography, retrospective electrocardiographically gated 64-slice CT (Siemens), and IVUS (40-MHz Atlantis; Boston Scientific). MLA was manually traced by 2 blinded and independent operators on 64-slice computed tomographic cross-sectional reconstruction and compared with IVUS MLA. A lesion was considered significant if the MLA was 相似文献   

Comparison of the degree of coronary stenoses by multidetector computed tomography versus by quantitative coronary angiography

Sixteen-slice multidetector computed tomography (MDCT) and quantitative coronary angiography (QCA) were performed in 29 patients. Quantification of the degree of luminal narrowing and lesion length measurements were performed independently on MDCT and QCA at 42 sites with sufficient computed tomographic image quality. The correlation between MDCT and QCA for quantifying the degree of stenosis was excellent (r2 = 0.93), although a systematic overestimation was observed by MDCT (bias 4% +/- 8%). The correlation between MDCT and QCA was moderate with respect to lesion length (r2 = 0.54). In the absence of severe calcifications or motion artifacts, MDCT permits noninvasive quantification of coronary stenosis.     

Comparison of eight- versus 16-slice multidetector-row computed tomography for visibility and image quality of coronary segments

Ten patients who underwent conventional coronary angiography (CA) were examined with both 8- and 16-slice multidetector-row computed tomography (MDCT) angiography within 6 months, and visibility and image quality of 16-slice MDCT-CA were compared with those of 8-slice MDCT-CA directly. In 136 segments determined by conventional CA, 101 (74.3%) and 126 (92.6%) segments were judged assessable by 8- and 16-slice MDCT-CA, respectively. Segment visibility in the right coronary and left circumflex arteries, as well as distal segments and small segments with diameters of <3.0 mm, was higher using 16-slice MDCT-CA than that of 8-slice MDCT-CA. As causes for invisibility in segments considered to be invisible, adjacent structures, as well as small diameters, were reduced by 16-slice MDCT-CA, suggesting that high spatial resolution contributes to higher visibility; however, nonassessable segments due to extensive calcium by 8-slice MDCT-CA were also judged nonassessable by 16-slice MDCT-CA.     

Serum cystatin C is associated with early stage coronary atherosclerotic plaque morphology on multidetector computed tomography

Objective

Cystatin C, a novel marker of kidney function, has been reported to be a predictor of adverse cardiovascular outcomes in patients without established chronic kidney disease. However, the relationship between serum cystatin C concentrations and early stage coronary atherosclerotic plaque morphology among patients with preserved kidney function has not been fully evaluated.

Methods and results

405 outpatients with early coronary artery disease with estimated glomerular filtration rate (eGFR) ≥60 ml/min/1.73 m² and <50% stenosis on 64-slice CT coronary angiography were enrolled. Subjects were categorized into quartiles by serum cystatin C (quartile I: ≤0.88 mg/L – quartile IV: ≥1.16 mg/L). Plaques in coronary segments were categorized as calcified or noncalcified. Multiple linear regression analysis revealed that lower eGFR, higher age, increasing numbers of noncalcified and calcified plaques, lower high-density lipoprotein cholesterol, and female gender were statistically significant predictors of increased cystatin C concentrations. The risk for presence of noncalcified plaques increased significantly with increasing quartiles of cystatin C. Compared with those in the lowest quartile, patients in each subsequent quartile were at steadily increased risk of having noncalcified plaque (quartile IV: OR 5.6; 95% CI 2.3–13.9, p-value <0.001). Both number of segments with calcified plaque and Agatston score were highly correlated with cystatin C concentrations (both p < 0.001), but when adjusted for segments with noncalcified plaque and other risk factors, calcified plaque segments were no longer independently predictive.

Conclusion

Higher serum cystatin C concentrations were correlated with early stage coronary atherosclerotic plaques among patients without established chronic kidney dysfunction. Noncalcified plaques increased with serum cystatin C concentrations, an association independent of eGFR and other cardiovascular risk factors.