Multislice spiral computed tomography angiography of mesenteric arteries

The introduction of multislice technology has improved and expanded the clinical applications of computed tomography angiography (CTA), and it is now possible to detect subtle vascular abnormalities. We optimised a high resolution CTA protocol to study the anatomy of mesenteric arteries with a multislice spiral CT scanner. We showed that multislice CTA produces images of high quality, with excellent anatomical visualisation of the main mesenteric trunks, and small collateral vessels. CTA may facilitate the diagnosis of vascular diseases, such as chronic mesenteric ischaemia, as well as acute disorders such as gastrointestinal bleeding.     

64排多层螺旋CT冠状动脉成像比较稳定性与不稳定性心绞痛患者冠状动脉粥样硬化斑块特征

目的 探讨64排多层螺旋CT冠状动脉成像比较稳定性心绞痛（SAP）与不稳定性心绞痛（UAP）患者粥样硬化斑块的特征.方法 对40例SAP患者、40例UAP患者进行64排多层螺旋CT冠状动脉成像,比较两组患者冠脉斑块的数量及斑块类型.对其中50例患者（26例UAP,24例SAP）罪犯斑块特征进行比较.结果 SAP组患者与UAP组患者斑块数量比较无显著性差异.UAP组患者非钙化性斑块、混合性斑块发生率较高.在对两组患者罪犯斑块特征进行比较的亚组分析中,UAP患者罪犯斑块非钙化性斑块、血管正性重构发生率以及血管重构指数明显高于SAP患者,在校正了年龄、性别、高血压病、糖尿病、高脂血症、吸烟等危险因素后,非钙化性斑块、血管正性重构与UAP显著相关.结论 64排多层螺旋CT冠状动脉成像显示：与SAP患者比较,UAP患者非钙化性斑块与混合性斑块发生率较高,罪犯斑块具有较高的非钙化性斑块及正性重构发生率.     

Multislice computed tomography coronary angiography: clinical applications

Cardiac and coronary computed tomography (CT) is becoming increasingly common in clinical practice. Even if there is no well-established evidence, this diagnostic modality is so strong and effective and, in skilled hand, it can be readily used in clinical practice. After learning its potential and the technical limits, this tool could be used for risk stratification as well as for revascularization evaluation. In this review, we will describe the results of present literature, clinical applications at present considered suitable to CT technology (i.e. 64-slice and dual-source scanners) and future applications and innovations.     

Regression of an atherosclerotic coronary artery plaque demonstrated by multislice spiral computed tomography in a patient with stable angina pectoris

Multislice spiral computed tomography (MSCT) permits direct visualization of not only coronary artery stenosis but also atherosclerotic plaques in patients with coronary artery disease. In this report, we describe a patient with stable angina in whom the regression of the plaque was documented by serial MSCT examinations. In the patient, a 46-year-old man with stable angina, MSCT revealed a stenotic lesion at the proximal portion of the left anterior descending artery. Axial, curved multiplanar reconstruction and cross-sectional images consistently depicted a protruding computed tomography low-signal mass suggesting an atherosclerotic plaque. Intracoronary ultrasound (ICUS) also documented an eccentric soft plaque with an echo-lucent mass suggesting a lipid core. Lipid-lowering therapy with pravastatin was started. Follow-up MSCT performed 7 months later documented an increase in the luminal area while the external vessel area remained unchanged. The regression of the plaque was also confirmed by a follow-up ICUS study. MSCT was thought to be feasible for serial evaluation of the plaque size and texture.     

Coronary computed tomography angiography in patients with stable coronary artery disease

The treatment of coronary artery disease (CAD), which is defined by stable anatomical atherosclerotic and functional alterations of epicardial vessels or microcirculation, focuses on managing intermittent angina symptoms and preventing major adverse cardiovascular events with optimal medical therapy. When patients with known CAD present with angina and no acute coronary syndrome, they have historically been evaluated with a variety of noninvasive stress tests that utilize electrocardiography, radionuclide scintigraphy, echocardiography, or magnetic resonance imaging for determining the presence and extent of inducible myocardial ischemia. Patient event-free survival, however, is largely driven by the coronary atherosclerotic disease burden, which is not directly assessed by functional testing. Direct evaluation of coronary atherosclerotic disease by coronary computed tomography angiography (coronary CTA) has emerged as the first line noninvasive imaging modality as it improves diagnostic accuracy and positively influences clinical management. Compared to functional assessment of CAD, coronary CTA-guided management results in improved patient outcomes by facilitating prevention of myocardial infarction. Other strengths of coronary CTA include detailed atherosclerotic plaque characterization and the ability to assess functional significance of specific lesions, which may further improve risk assessment and prognosis and lead to more appropriate referrals for additional testing, such as invasive coronary angiography.     

Influence of coronary computed tomographic angiography on patient treatment and prognosis in patients with suspected stable angina pectoris

We evaluated the influence of coronary computed tomographic angiography (CTA) as a first-line diagnostic test on patient treatment and prognosis. A total of 1,055 consecutive patients with suspected stable angina pectoris (mean age 55 ± 10 years, 56% women) and a low to intermediate pretest likelihood of coronary artery disease (CAD) were included in the present study. The patients were followed for a median of 18 months. The use of downstream diagnostic testing and medical therapy after CTA were recorded. The CTA result was normal in 49%, and nonobstructive and obstructive CAD (≥50% stenosis) was demonstrated in 31% and 15% of the patients, respectively. Coronary CTA was inconclusive in 5% of the patients. The use of antiplatelet therapy decreased with normal findings from CTA, and the use of antiplatelet and lipid-lowering agents increased in patients with CAD. Additional testing was performed in 2% of patients with normal CTA findings and in 7% and 82% of patients with nonobstructive or obstructive CAD, respectively. No patients without CAD, 0.9% of patients with nonobstructive CAD, and 1.9% of patients with obstructive CAD met the primary end point (cardiovascular death and myocardial infarction, p = 0.008). No patients without CAD, 1.5% of patients with nonobstructive CAD, and 30% patients with obstructive CAD met the secondary end point (cardiovascular death, myocardial infarction, and coronary revascularization, p <0.0001). In conclusion, in patients suspected of having angina, the findings from CTA influence patient treatment without resulting in excessive additional testing. Coronary CTA provides important prognostic information, with excellent intermediate-term outcomes in patients with normal CTA findings.     

Multidetector computed tomography evaluation of coronary plaque morphology in patients with stable angina

The purpose of this study was to evaluate the morphology and composition of atherosclerotic coronary plaques in patients with stable coronary artery disease by 64-row multidetector computed tomography (CT) angiography. A total of 56 patients were divided into an ischemia-related (n = 31) and a nonischemia-related lesion group (n = 25) based on myocardial perfusion scintigraphy, invasive angiography, and 1-year clinical follow-up. The 56 lesions detected by CT imaging were analyzed; the severity of stenosis, the lesion length, CT attenuation value, and calcium deposition of the plaques were evaluated. Clinical characteristics and CT findings were compared using univariate and multivariate logistic regression analyses. Ischemia-related lesions exhibited a greater severity of coronary stenosis, were longer (17.8 ± 8.5 vs 9.1 ± 3.9 mm), and had a higher CT attenuation value (101.7 ± 36.7 vs 81.6 ± 32.6 HU) and larger calcium deposition. By univariate logistic analysis, severity of stenosis, lesion length, CT attenuation value, and calcium deposition were significantly associated with ischemia-related plaques. The odds ratio (OR) of these parameters was 6.874 (P = 0.007), 1.371 (P = 0.001), 1.018 (P = 0.044), and 5.400 (P = 0.004), respectively. By multivariate logistic analysis, the severity of stenosis and lesion length were significantly associated with ischemia-related plaques (OR 7.588, P = 0.036 and OR 1.365, P = 0.003, respectively). In conclusion, coronary CT angiography is useful for the identification of morphological differences between ischemia-related and nonischemia-related plaques in patients with stable coronary artery disease.     

Multislice computed tomography angiography in the diagnosis of coronary artery disease

Multislice CT angiography represents one of the most exciting technological revolutions in cardiac imaging and it has been increasingly used in the diagnosis of coronary artery disease. Rapid improvements in multislice CT scanners over the last decade have allowed this technique to become a potentially effective alternative to invasive coronary angiography in patients with suspected coronary artery disease. High diagnostic value has been achieved with multislice CT angiography with use of 64- and more slice CT scanners. In addition, multislice CT angiography shows accurate detection and analysis of coronary calcium, characterization of coronary plaques, as well as prediction of the disease progression and major cardiac events. Thus, patients can benefit from multislice CT angiography that provides a rapid and accurate diagnosis while avoiding unnecessary invasive coronary angiography procedures. The aim of this article is present an overview of the clinical applications of multislice CT angiography in coronary artery disease with a focus on the diagnostic accuracy of coronary artery disease; prognostic value of coronary artery disease with regard to the prediction of major cardiac events; detection and quantification of coronary calcium and characterization of coronary plaques. Limitations of multislice CT angiography in coronary artery disease are also briefly discussed, and future directions are highlighted.     

多层面螺旋CT冠状动脉成像在冠心病中的应用

目的　评价多层面螺旋CT(MSCT)行冠状动脉血管造影和三维重建在冠心病中的应用价值。方法　对 30例冠心病患者进行了心电门控MSCT增强扫描 ,在工作站对图像资料进行了最大密度投影法 (MIP)三维重建 ,并与冠状动脉造影结果相对照。结果　 30例患者中对 12 0支冠状动脉血管 (左主干、左前降支、回旋支、右冠状动脉 )进行了MSCT三维重建 ,图像质量良好者为 84支 (70 % ) ,影响图像质量的主要因素是心脏搏动造成的伪影 ;9例冠状动脉支架和 5例冠状动脉搭桥术后均可清晰显示支架和血管桥的位置及远端血流情况 ,对于显示近中端高度 (>75 % )或完全梗阻性病有一定的准确性 (敏感性 80 % ,特异性 79.8% )。而不能显示轻度狭窄病变、远端或细小分支病变。结论　MSCT血管造影和三维重建在冠心病诊断和对病变血管的评价 ,以及血运重建术后复查等方面有一定的应用价值。     

Comparison of diagnostic accuracy of 64-slice computed tomography coronary angiography in women versus men with angina pectoris

We compared the diagnostic accuracy of 64-slice computed tomographic (CT) coronary angiography to detect significant coronary artery disease (CAD) in women and men. The 64-slice CT coronary angiography was performed in 402 symptomatic patients, 123 women and 279 men, with CAD prevalence of 51% and 68%, respectively. Significant CAD, defined as > or =50% coronary stenosis on quantitative coronary angiography, was evaluated on a patient, vessel, and segment level. The sensitivity and negative predictive value to detect significant CAD was very good, both for women and men (100% vs 99%, p = NS; 100% vs 98%, p = NS), whereas diagnostic accuracy (88% vs 96%; p <0.01), specificity (75% vs 90%, p <0.05), and positive predictive value (81% vs 95%, p <0.001) were lower in women. The per-segment analysis demonstrated lower sensitivity in women compared with men (82% vs 93%, p <0.001). The sensitivity in women did not show a difference in proximal and midsegments, but was significantly lower in distal segments (56% vs 85%, p <0.05) and side branches (54% vs 89%, p <0.001). In conclusion, CT coronary angiography reliably rules out the presence of obstructive CAD in both men and women. Specificity and positive predictive value of CT coronary angiography were lower in women. The sensitivity to detect stenosis in small coronary branches was lower in women compared with men.     

Differential coronary artery calcification detected by electron beam computed tomography as an indicator of coronary stenosis among patients with stable angina pectoris.

BACKGROUND: The detection of coronary artery calcification by electron beam computed tomography (EBCT) has been suggested as an indicator of atherosclerosis and coronary artery disease (CAD). There is no consensus on the correlation between coronary calcification and angiographically significant stenosis on an artery-by-artery basis. OBJECTIVE: To examine the relationship between coronary calcification score (CCS) and the presence of significant CAD on an artery-by-artery basis in patients with stable angina pectoris. METHODS AND RESULTS: EBCT and coronary angiogram (CAG) were evaluated in 71 patients with stable angina and in nine control subjects. The CCSs of each of the four major coronary arteries were highest in patients with significant CAD (n=43), followed by patients with insignificant CAD (n=5), patients with syndrome X (n=23) and control subjects, respectively. Calcification scores of the four major coronary arteries appeared to have different predictive power for significant stenosis on the same vessel. For left main (LM) and left anterior descending (LAD) coronary arteries, CCSs of vessels with significant stenoses were not different from those without significant stenoses (values expressed as medians: LM 0 versus 1; LAD 98.5 versus 70; not significant). Calcification scores of left circumflex (LCX) and right coronary arteries (RCA) were significantly higher in vessels with significant stenosis (LCX 49.5 versus 0; RCA 53 versus 1; P<0.05). CCSs appeared to be moderately useful to predict significant stenoses in these two vessels (areas under receiver operating characteristic curves: LCX 0.68+/-0.08, 95% CI 0.52 to 0.81; RCA 0.71+/-0.08, 95% CI 0.55 to 0.84). CONCLUSIONS: The CCSs of RCA and LCX arteries, but not those of LM and LAD arteries, may predict significant angiographic stenosis on an artery-by-artery basis among patients with stable angina pectoris.     

Non-invasive coronary angiography with 16 multidetector-row spiral computed tomography: a comparative study with invasive coronary angiography

INTRODUCTION AND OBJECTIVES: Non-invasive coronary artery angiography by 16 multidetector-row spiral computed tomography is a novel diagnostic tool whose reliability is still unclear. The aim of our study was to compare this technique with invasive coronary angiography. PATIENTS AND METHOD: A total of 31 selected patients were examined with both angiographic methods. Non-invasive studies were performed with a helical computer tomography system (Toshiba Aquilion 16-slices). A contrast agent was injected into a peripheral vein, and cross-sectional images were reconstructed with a slice thickness of 0.5 mm or 1.0 mm. Findings from both techniques were analyzed according to a predetermined segmented anatomical model of the coronary artery. The detection and relevance of coronary artery lesions were evaluated, and lesions with a reduction in diameter of more than 50% were considered significant. RESULTS: Non-invasive coronary angiography yielded an appropriate assessment in 88.4% of the coronary artery segments. The reasons that prevented correct segment evaluation were extensive coronary calcifications, inappropriate breath-hold, motion artefacts and small vessel size. Sensitivity and specificity for the detection of significant coronary lesions with the non-invasive method were 75% and 91%, respectively. Sensitivity and specificity for individual coronary artery segments were as follows: proximal, 89% and 93%; medial, 87% and 90%; distal, 50% and 90%; and secondary branches, 62% and 92%. CONCLUSIONS: Non-invasive coronary artery angiography with 16 multidetector-row computed tomography is a powerful diagnostic tool, especially for the evaluation of the proximal and medial segments of the major coronary arteries.     

Preconditioning effect during coronary angioplasty in patients with stable angina pectoris

OBJECTIVE: To determine whether collateral recruitment is involved in the preconditioning effect on the electrocardiogram, chest symptoms, and lactate metabolism during coronary angioplasty in patients with stable angina pectoris. METHODS AND PATIENTS: Sixteen patients with stable angina pectoris underwent three consecutive 2-min balloon inflations 5-min apart. The greatest ST elevation (deltaSTmax), the sum of ST elevations in all leads (sum(ST)), and QT dispersion (QTd) were measured at the end of each balloon inflation. Chest pain score was evaluated on a scale ranging from no pain (0) to the most severe pain (10). Lactate extraction ratio (LER) was determined by simultaneous blood sampling from the aorta and the coronary sinus. Collateral flow index (CFI) was derived from simultaneous measurements of mean aortic pressure and coronary wedge pressure obtained from a pressure guidewire during balloon inflation. RESULTS: Significant decreases were noted in deltaSTmax (3.3+/-2.1 vs. 3.0+/-1.9 vs. 2.6+/-1.8 mm, p<0.01), sum(ST) (9.7+/-7.2 vs. 8.5+/-6.1 vs. 6.9+/-5.3 mm, p<0.01), QTd (55.3+/-13.8 vs. 46.9+/-9.0 vs. 42.5+/-10.0 ms, p<0.01), and chest pain score (4.3+/-3.1 vs. 2.8+/-2.6 vs. 1.4+/-1.5, p<0.01) during the three sequential balloon inflations. LER significantly increased (-55.5+/-47.8 vs. -36.7+/-34.3 vs. -19.6+/-26.2%, p<0.01), indicating decreased lactate production. No significant difference was observed in CFI (0.16+/-0.10 vs. 0.15+/-0.10 vs. 0.15+/-0.10). CONCLUSION: Repeated balloon inflations during coronary angioplasty elicited a preconditioning effect on ST-segment shift, QT dispersion, chest pain, and lactate production that does not involve collateral recruitment.     

光学相干断层扫描比较不稳定性和稳定性心绞痛患者粥样硬化斑块特征

Objective To compare the characterization of coronary atherosclerotic plaques in patients with unstable angina pectoris (UAP) and stable angina pectoris (SAP) by optical coherence tomography (OCT). Methods OCT was performed in 47 patients (23 UAP and 24 SAP) undergoing coronary angiography. Lipid-rich plaque (defined by ≥ 2 quandrants of the cross-section area), thin cap fibroatheroma (TCFA), thickness of fibrous cap, plaque rupture, calcification and thrombus visualized by OCT were compared between UAP and SAP patients. Results OCT imaging was successfully in 44 out of 47 patients (22 UAP, 22 SAP). Proportion of lipid-rich plaques was similar between UAP and SAP groups [91% (20/22) vs, 73% (16/22),P =0. 741]. The minimum thickness of fibrous cap in the UAP group was significantly thinner than that in SAP group [(69.5±34.7) μm vs. (141.1±68.5) μm, P = 0.000] and the rate of fibrous cap erosion in the UAP group was significantly higher than that in the SAP group [59% (13/22) vs. 9% (2/22), P=0.000]. Percents of TCFA [73% (16/22) vs. 14% (3/22) ,P = 0.000] and plaque rupture [50% (11/22) vs.9% (2/22) , P = 0.003] were significantly higher in UAP group compared those in SAP group. Incidence of thrombus and calcification were similar between two groups. Conclusions OCT imaging can clearly define plaque characterization of coronary atherosclerosis. UAP patients have thinner fibrous cap, higher incidences of fibrous cap erosion, plaque rupture and TCFA compared patients with SAP.     

光学相干断层扫描比较不稳定性和稳定性心绞痛患者粥样硬化斑块特征

Objective To compare the characterization of coronary atherosclerotic plaques in patients with unstable angina pectoris (UAP) and stable angina pectoris (SAP) by optical coherence tomography (OCT). Methods OCT was performed in 47 patients (23 UAP and 24 SAP) undergoing coronary angiography. Lipid-rich plaque (defined by ≥ 2 quandrants of the cross-section area), thin cap fibroatheroma (TCFA), thickness of fibrous cap, plaque rupture, calcification and thrombus visualized by OCT were compared between UAP and SAP patients. Results OCT imaging was successfully in 44 out of 47 patients (22 UAP, 22 SAP). Proportion of lipid-rich plaques was similar between UAP and SAP groups [91% (20/22) vs, 73% (16/22),P =0. 741]. The minimum thickness of fibrous cap in the UAP group was significantly thinner than that in SAP group [(69.5±34.7) μm vs. (141.1±68.5) μm, P = 0.000] and the rate of fibrous cap erosion in the UAP group was significantly higher than that in the SAP group [59% (13/22) vs. 9% (2/22), P=0.000]. Percents of TCFA [73% (16/22) vs. 14% (3/22) ,P = 0.000] and plaque rupture [50% (11/22) vs.9% (2/22) , P = 0.003] were significantly higher in UAP group compared those in SAP group. Incidence of thrombus and calcification were similar between two groups. Conclusions OCT imaging can clearly define plaque characterization of coronary atherosclerosis. UAP patients have thinner fibrous cap, higher incidences of fibrous cap erosion, plaque rupture and TCFA compared patients with SAP.