Assessment of obstruction length and optimal viewing angle from biplane X-ray angiograms

Three-dimensional quantitative coronary angiography (3D QCA) has been encouraged by the increasing need to better assess vessel dimensions and geometry for interventional purposes. A novel 3D QCA system based on biplane X-ray angiograms is presented in this paper. By correcting for the isocenter offset and by improving the epipolar constraint for corresponding two angiographic projections, accurate and robust reconstruction of the vessel centerline is achieved and the reproducibility of its applications, e.g., the assessments of obstruction length and optimal viewing angle, is guaranteed. The accuracy and variability in assessing the obstruction length and optimal bifurcation viewing angle were investigated by using phantom experiments. The segment length assessed by 3D QCA correlated well with the true wire segment length (r ² = 0.999) and the accuracy and precision were 0.04 ± 0.25 mm (P < 0.01). 3D QCA slightly underestimated the rotation angle (difference: −1.5° ± 3.6°, P < 0.01), while no significant difference was observed for the angulation angle (difference: −0.2° ± 2.4°, P = 0.54). In conclusion, the new 3D QCA approach allows highly accurate and precise assessments of obstruction length and optimal viewing angle from X-ray angiography.     

Optimization of acquisition trajectories for 3D rotational coronary venography

Objective  

Rotational coronary X-ray imaging on C-arm systems provides a multitude of diagnostic projections from the vascular tree with a single contrast agent bolus. The acquisition trajectory is typically limited to a circular arc with a fixed caudo-cranial angulation. This may cause sub- optimal projection directions for specific vessel segments for all acquired views, e.g., those segments orthogonal to the axis of rotation. In this paper, a method is presented to calculate a patient-independent acquisition trajectory with respect to vessel foreshortening and overlap for multiple vessel segments of the coronary tree. This method can be applied to artery as well as vein anatomy.     

3D coronary reconstruction from routine single-plane coronary angiograms: Clinical validation and quantitative analysis of the right coronary artery in 100 patients

Background: Current coronary angiographic techniques display complex three-dimensional (3D) coronary structures in two dimensions (2D). We have developed a 3D reconstruction (3DR) algorithm using standard single-plane angiographic images that allows for 3D display of coronary structures. The purpose of this study was to validate our 3DR algorithm and quantify anatomic characteristics of the right coronary artery (RCA) in vivo. Methods: Accuracy and reproducibility studies were performed using 3DRs of a coronary phantom and in vivo following 3DRs in 40 patients. The anatomic features of the RCA were then quantified in 100 patients. Results: Comparison of length and bifurcation angles (BA) from the phantom to the 3DRs revealed good accuracy and correlation for both (r = 0.95 and 0.93 respectively), with diameter error of <7%. In vivo, the average root mean square (RMS) error in the spatial coordinates of the vessel centerlines was 3.12 ± 0.77 and 3.16 ± 0.75 mm in 20 left coronary arteries (LCA) and 20 RCAs respectively. Interobserver average RMS error was 3.47 ± 1.96 mm and intraobserver average RMS error was 3.02 ± 1.07 and 3.44 ± 1.57 mm for two different operators (p = NS). The average RCA length was 10.2 ± 1.7 cm, average radius of curvature (ROC) was 52 ± 9°, and the average 3D bifurcation angle of the posterior descending artery (PDA) from the RCA was 55 ± 22°. Foreshortening (FS) of the segments of the RCA in three 'standard’ projections ranged from 0–60, 0–75, and 0–82% respectively. Conclusions: Using our 3DR algorithm patient-specific anatomic characteristics can be accurately displayed and quantified, expanding the information that can be derived from routine coronary angiography.     

Three-dimensional coronary imaging for the ostium of the left anterior descending artery

Conventional coronary angiography is subject to a significant foreshortening of the proximal left anterior descending artery and overlapping of the left anterior descending artery and the circumflex artery that limits the accurate identification of the ostium of the left anterior descending artery. The aim of this study was to determine whether the three-dimensional (3D) reconstruction of traditional coronary angiography could optimize the projection angle to clearly show the ostium of the left anterior descending artery. The left main bifurcations of 18 consecutive patients were analyzed. A 3D image of the bifurcation was reconstructed from two conventional images and the optimal projection angle was chosen to clearly identify the ostium of the left anterior descending artery. The optimal angle was the right anterior oblique 18.8 ± 20.9°-caudal 26.9 ± 32.3°. The length from the left main trunk to the proximal left anterior descending artery on the optimal views was significantly longer than that on the routine views (25.0 ± 6.1 vs. 22.4 ± 5.3 mm, P = 0.011). The angles of the left main bifurcations were not substantially different between the optimal and the routine views. The optimal views selected using the 3D system provided clearer images of the ostium of the left anterior descending artery with less overlapping and foreshortening. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Non-invasive coronary angiography: the clinical value of multi-slice computed tomography in the assessment of patients with prior coronary bypass surgery

Background Contrast enhanced multi-slice computed tomography (MSCT) is the leading modality in non-invasive coronary angiography (CTA) today. We investigated MSCT based assessment of coronary artery bypass grafts (CABG) by analyzing assets and drawbacks of CTA in order to define demands on latest technology. Methods In a clinical setting 39 CABG patients (69.2 ± 1.4 years; male n = 36) underwent CTA (collimation 16 × 0.75 mm, contrast medium 100 ml; 320 mAs, 120 KV). Ninety-seven CABG (61 venous, 36 arterial grafts) were evaluated. A subgroup of 18 patients underwent additional invasive coronary angiography (CA). Results CTA for CABG assessment resulted in an overall sensitivity (sens.) of 100%, specificity (spec.) of 92.4% and positive and negative predictive values (PPV, NPV) of 60% and 100%, respectively. CABG anastomoses showed slightly inferior diagnostic accuracy than other CABG segments. Limitations in imaging quality caused 21% unevaluable segments of the CABG anastomoses. Evaluation of native vessel segments proximal and distal to the anastomoses resulted in a sens, spec, PPV and NPV of 57.5, 94.6, 92 and 67.3%, respectively. With 28.5% unevaluable segments, the native vessel segments showed serious limitations in imaging quality. Radiation exposure was 9.88 ± 3.20 mSv (9.69 ± 3.25 mSv male; 12.08 ± 1.35 mSv female). Conclusion 16-slice MSCT based CABG assessment offers sufficient diagnostic accuracy. However, focussing on the bypass anastomoses and the native revascularized coronary arteries, clinical value is limited.     

3.0T磁共振全心方法冠状动脉造影的初步评价

目的初步评价三维(3D)全心方法冠状动脉造影在3.0T磁共振应用的可行性及价值。方法采用3D分段k空间快速梯度回波序列(turbofieldecho,TFE),实时呼吸导航门控技术,心电向量(VCG)R波触发门控技术,在3.0T磁共振对12例健康志愿者进行磁共振冠状动脉造影(MRCA)检查。结果左主干和左前降支(LM LAD)、左旋支(LCX)及右冠状动脉(RCA)的血管长度(mm)分别为98±16、56±9、108±29;血管直径(mm)分别为2.6±0.4、2.4±0.3、2.6±0.3;左、右冠状动脉的信噪比(SNR)和强化噪声比(CNR)分别为35±12、19±6和23±5、18±3。结论初步研究显示全心方法MRCA在3.0T磁共振是可行的,能够显示冠状动脉的远段和管径较小的分支血管,显示了增强的信噪比。全心方法使冠状动脉定位采集过程变得简单,易操作。     

冠状动脉造影投照体位与患者体型及心型关系的定量分析

背景:冠脉动脉造影被称为诊断冠心病的"金标准",但由于投照体位的不当,造成病变血管段人为"缩短"及冠状动脉显影影像质量较差等均可引起误诊或漏诊.目的:探讨不同体型、心型患者的冠状动脉主干及各分支的最佳投照体位的特异性关系.设计:对照观察.单位:南昌大学第二附属医院心内科.对象:2001-11/2006在南昌大学第二附属医院行行冠状动脉造影术患者1 369例.所有受试者均签署了冠状动脉造影书面知情同意书,实验方案得到了南昌大学医学院医学伦理委员会的批准.方法:将1 369例患者分为3组:①肥胖组:体质量指数26～31 kg/m2,489例,横位心.②普通体型组:体质量指数23～25 kg/m2,502例,普通心型.③消瘦组:体质量指数17～22 kg/m2,378例,垂位心型.对3组受试者的左冠状动脉主干,前降支近段,前降支中远段、回旋支近段、回旋支中远段、右冠状动脉近中段,远段等血管的Compart分析结果进行归纳.主要观察指标:最佳造影角度.结果:1 369例均进入结果分析.①冠状动脉主干最佳造影角度:左前斜位(45±5)°/足位(25±5)°或右前斜位25°/足位35°,肥胖者其角度大10°左右,消瘦者小10°左右(P均﹤0.05).②前降支近段最佳造影角度:右前斜位(50±8)°/头位(23±8)°,肥胖者其角度大10°左右,消瘦者其角度小10°左右(P均﹤0.05).③前降支中远段最佳造影角度:右前斜位(40±5)°/头位(45±5)°或左前斜位(11±5)°/头位(45±5)°.④回旋支近段最佳造影角度:左前斜位(45±5)°/足位(35±5)°或AP/足位36°.⑤回旋支中远端最佳造影角度:左前斜位(45±5)°/足位(35±5)°或右前斜位(6±4)° 足位(33±5)°.⑥右冠状动脉近中段最佳造影角度:左前斜位(35±5)°/足位(14±5)°或左前斜位(48±5)°/头位(15±5)°,肥胖、消瘦组左前斜位角度都要大15°左右,右前斜位胖者角度小10°左右,瘦者角度大10°左右(P < 0.05).⑦右冠状动脉远段最造影角度:左前斜位(53±5)°/足位(17±5)°.结论:通过这些体位的投照多能清楚了解整个冠脉的情况,最佳造影角度下的血管狭窄百分比测量能显著提高其定量分析的精度.     

Impact of analyzing less image frames per segment for radiofrequency-based volumetric intravascular ultrasound measurements in mild-to-moderate coronary atherosclerosis

Volumetric radiofrequency-based intravascular ultrasound (RF–IVUS) data of coronary segments are increasingly used as endpoints in serial trials of novel anti-atherosclerotic therapies. In a relatively time-consuming process, vessel and lumen contours are defined; these contours are first automatically detected, then visually checked, and finally (in most cases) manually edited to generate reliable volumetric data of vessel geometry and plaque composition. Reduction in number of cross-sectional images for volumetric analysis could save analysis time but may also increase measurement variability of volumetric data. To assess whether a 50% reduction in number of frames per segment (every second frame) alters the reproducibility of volumetric measurements, we performed repeated RF–IVUS analyses of 15 coronary segments with mild-to-moderate atherosclerosis (20.2 ± 0.2 mm-long segments with 46 ± 13% plaque burden). Volumes were calculated based on a total of 731 image frames. Reducing the number of cross-sectional image frames for volumetric measurements saved analysis time (38 ± 9 vs. 68 ± 17 min/segment; P < 0.0001) and resulted for only a few parameters in (borderline) significant but mild differences versus measurements based on all frames (fibrous volume, P < 0.05; necrotic-core volume, P = 0.07). Compared to the intra-observer variability, there was a mild increase in measurement variability for most geometrical and compositional volumetric RF–IVUS parameters. In RF–IVUS studies of mild-to-moderate coronary disease, analyzing less image frames saved analysis time, left most volumetric parameters greatly unaffected, and resulted in a no more than mild increase in measurement variability of volumetric data.     

Three-dimensional, time-resolved motion of the coronary arteries.

BACKGROUND: Coronary artery motion can decrease image quality during coronary magnetic resonance angiography and computed tomography coronary angiography. PURPOSE: To characterize the three-dimensional motion of the coronary arteries along the entire vessel length and to identify the temporal location and duration of periods of relatively low cardiac motion in patients with coronary artery disease. METHODS: Archived digital, biplane x-ray angiography films acquired at 30 frames per second with simultaneous electrocardiogram recording were reviewed for 15 patients with coronary artery disease. The right coronary (RCA), left anterior descending (LAD), and left circumflex (LCX) arteries were divided into proximal, mid, and distal segments. The displacement and velocity of a point in each segment were calculated throughout the heart cycle. Time-dependent, three-dimensional motion of each segment on each vessel was determined. Periods of the heart cycle during which maximal displacement was less than 1 mm or 0.5 mm per frame for each artery were determined. RESULTS: A period lasting an average of 187 msec was seen during mid-diastole (72+/-5% of the cardiac cycle) in which all three coronary arteries studied had relatively little motion. This period of quiescence was consistent along the length of the arteries. Although the amount of motion did vary along the length of the arteries, there was no difference in the timing of rest periods in the proximal, mid, and distal segments using a < 1 mm per frame threshold. The periods of low motion were significantly reduced in length and often altogether eliminated when the 0.5 mm per frame threshold was used.     

Low-dose coronary computed tomography angiography using prospective ECG-triggering compared to invasive coronary angiography

To assess the diagnostic accuracy of prospective ECG-triggering 64-slice multidetector computed tomography (MDCT) coronary angiography for evaluation of coronary artery disease (CAD). Forty-two patients (31 males, 11 females, mean age 64 years) underwent cardiac CT and invasive coronary angiography (ICA). Patients with a heart rate of <65 beats/min with stable heart rhythm were included in the study sample. We used a prospective ECG-triggering protocol. Luminal narrowing over 50% was considered to be significant according to a modified 17-segment AHA model, using invasive coronary angiography (ICA) as the standard of reference. The mean radiation dose was 3.5 mSv ± 0.3 (range, 3.3–4.2 mSv), and 542 of 549 segments (98.7%) in the 42 patients were diagnostic. In contrast, 119 of 542 segments (22%) were diagnosed as significant by ICA. The sensitivity, specificity, accuracy, PPV and NPV were 95.0, 96.2, 96, 85.8 and 98.8%, respectively. False positive results were affected by densely calcified plaques, whereas false negatives were caused by motion artifact with poor vessel attenuation at the distal segments or near the bifurcation area of the coronary arteries. Prospective ECG-triggering MDCT is a useful method for evaluating CAD in patients with a lower heart rate with low radiation dose.     

320-row CT coronary angiography: effect of 100-kV tube voltages on image quality,contrast volume,and radiation dose

To prospectively evaluate image quality parameters, contrast volume and radiation dose at the 100-kilovolt (kV) setting during coronary computed tomographic angiography (CCTA) on a 320-row computed tomography scanner. We enrolled 107 consecutive patients with a heart rate <65 beats per minute (bpm) undergoing prospective electrocardiogram (ECG)-triggered CCTA. Forty patients with a body mass index (BMI) <25 kg/m² were scanned using 100-kV tube voltage settings, while 67 patients were scanned using 120-kV protocols. Image quality was assessed by two readers unaware of patient information and scan parameters. Attenuation in the aorta and perivascular fat tissue and image noise were measured. Contrast-to-noise ratios (CNRs) and contrast material volumes were calculated. The effective radiation doses were estimated using a chest conversion coefficient (0.017). Diagnostic image quality was achieved in 98.2% of coronary segments with 100-kV CCTA and 98.6% of coronary segments with 120-kV CCTA, with no significant differences in image quality scores for each coronary segment. Vessel attenuation, image noise, and CNR were not significantly different between the 100- and 120-kV protocols. Mean contrast injection rate and mean material volume were significantly lower for the 100-kV CCTA (4.35 ± 0.28 ml/s and 53.13 ± 3.77 ml, respectively) than for the 120-kV CCTA (5.16 ± 0.21 ml/s and 62.40 ± 3.66 ml respectively; P < 0.001). The effective radiation dose was 2.12 ± 0.19 mSv for 100-kV CCTA, a reduction of 54% compared to 4.61 ± 0.82 mSv for 120-kV CCTA. A 100-kV CCTA can be implemented in patients with a BMI < 25 kg/m². The 100-kV setting allows significant reductions in contrast material volume and effective radiation dose while maintaining adequate diagnostic image quality.     

Arterial supply of the sinoatrial node: a CT coronary angiographic study

We aimed to investigate the variances in especially the origin, course and termination of the sinoatrial node (SAN) artery in this study, using coronary CT angiography. The coronary CT angiography images of 251 patients (190 men and 61 women; age range, 20–82 years; mean age, 54.4 ± 13.6 years) were retrospectively analyzed. The SAN artery (arteries) in each case was named according to a special nomenclature with regard to their origin, course and termination. The sinoatrial node was being vascularized by a single artery in 241 (96%) cases and by two arteries in 10 (4%) cases. It was arising from RCA in 139 (55.4%) cases, from LCX in 99 (39.4%) cases, from the aorta in 2 (0.8%) cases, and from the bronchial artery in 1 (0.4%) case. The mean diameter of the SAN arteries was 2.3 mm. The mean distance between the origin of the SAN artery from RCA and the RCA ostium was 16.2 mm, from LCX and the origin of LCX was 19.3 mm. Frequency of the atrial branch was 35.9%. S-shaped SAN artery is determined in 51 (20.3%) cases. Coronary CT angiography is considerably effective in depicting the various vascularization types of SAN.     

Signal density of left ventricular myocardial segments and impact of beam hardening artifact: implications for myocardial perfusion assessment by multidetector CT coronary angiography

We sought to explore the normal myocardial signal density (SD) levels during multidetector computed tomography coronary angiography (MDCT-CA) acquisitions and evaluated the impact of beam hardening artifacts. Background: Since myocardial perfusion by MDCT is based on the myocardial signal density (SD), it is pivotal to determine the normal values of myocardial SD and to identify potential mechanisms of misinterpretation of perfusion defects. In routine MDCT acquisitions, we commonly visualize a considerable SD drop at the posterobasal wall resembling perfusion defects, being attributed to beam hardening artifacts. Consecutive asymptomatic patients without history of coronary artery disease (CAD) and low probability of CAD who were referred for MDCT evaluation at our institution due to inconclusive or discordant functional tests constituted the study population. Perfusion defects were defined as a myocardial segment having a SD two standard deviations below the average myocardial SD for the 16 left ventricular American Heart Association (AHA) segments. Thirty six asymptomatic patients constituted the study population. Myocardial SD was evaluated in 576 American Heart Association (AHA) segments and 36 posterobasal segments. The mean myocardial SD at the posterobasal segment was 53.5 ± 35.1 HU, whereas the mean myocardial SD at the basal, mid and apical myocardium was 97.4 ± 17.3, with significant differences (p < 0.001) between posterobasal and all AHA segments. Posterobasal “perfusion defects” were identified in 26 (72%) patients. The only variable associated to the presence of posterobasal SD deficit was the heart rate (61.8 ± 6.2 bpm vs. 56.3 ± 8.1 bpm, p = 0.04), whereas body mass index, blood SD of the left and right ventricles, contrast-to-noise ratio, and the extent of atherosclerosis were not related to the presence of “perfusion defects”. In an asymptomatic population with no history of coronary artery disease, a myocardial signal density deficit mimicking a perfusion defect is a common finding in the posterobasal wall and is not related to body mass index or scan quality.     

Optimizing contrast medium injection protocol individually with body weight for high-pitch prospective ECG-triggering coronary CT angiography

To individually optimize contrast medium protocol for high-pitch prospective ECG-triggering coronary CT angiography using body weight. Ninety patients undergoing high-pitch coronary CT angiography were randomly assigned to 3 contrast medium injection protocols with bolus tracking technique: Group A, 0.7 ml CM per kg patient weight (ml/kg); Group B, 0.6 ml/kg; Group C, 0.5 ml/kg. Each group had 30 patients. The CT values of superior vena cava (SVC), pulmonary artery (PA), ascending aorta (AA), left atrium (LA), left ventricle (LV), left main artery (LM) and proximal segment of right coronary artery (RCA) were measured. The image quality of coronary artery was evaluated on per-segment basis using a 4-point scale (1-excellent, 4-non-diagnosis). The CT value was not significantly different on AA (p = 0.735), LM (p = 0.764), and proximal segment of RCA (p = 0.991). The CT value was significantly different on SVC, PA, LA and LV (all p < 0.05). The mean image quality score was 1.6 ± 0.1, 1.6 ± 0.1 and 1.6 ± 0.1 (p = 0.217). The volume of CM was 47 ± 8, 44 ± 8 and 36 ± 6 ml for 3 groups (p < 0.001). The effective radiation dose was 0.88 ± 0.04, 0.87 ± 0.06, and 0.85 ± 0.07 mSv for 3 groups. Contrast medium could be reduced to 0.5 ml/kg for high-pitch coronary CT angiography without compromising diagnostic image quality, which associated ~50 % reduction of total contrast volume compared with standard contrast protocol with test bolus technique.     

MR冠脉成像靶容积与全心扫描方法的优势探讨

目的探讨自由呼吸导航三维采样磁共振冠脉成像靶容积和全心扫描方法的特点与优势。方法对21例志愿者进行1.5T自由呼吸磁共振冠脉成像扫描,包括右冠状动脉和左旋支的靶容积及全心扫描,两种方法的基本扫描参数相同,扫描完成进行后处理,得到靶容积和全心扫描的右冠状动脉及左旋支图像,对右冠脉及左旋支各节段的图像质量进行评分,测量右冠脉及左旋支的长度,观察右冠脉后降支的显示情况,评价两种方法的特点和优势。结果全心扫描的时间明显长于单次冠脉靶容积扫描的时间,两种方法在显示右冠状动脉和左冠脉旋支的长度上无明显差别,对于右冠状动脉后降支的显示而言,全心扫描较靶容积扫描具有明显的优势,在图像质量方面,靶容积扫描优于全心扫描方法。结论自由呼吸导航三维采样磁共振冠脉成像靶容积和全心扫描方法具有各自的优势,在临床中可根据具体情况进行选择应用或联合应用。     

Prospectively versus retrospectively ECG-gated 256-slice coronary CT angiography: image quality and radiation dose over expanded heart rates

To compare image quality and radiation dose estimates for coronary computed tomography angiography (CCTA) obtained with a prospectively gated transaxial (PGT) CT technique and a retrospectively gated helical (RGH) CT technique using a 256-slice multidetector CT (MDCT) scanner and establish an upper limit of heart rate to achieve reliable diagnostic image quality using PGT. 200 patients (135 males, 65 females) with suspected coronary artery disease (CAD) underwent CCTA on a 256-slice MDCT scanner. The PGT patients were enrolled prospectively from January to June, 2009. For each PGT patient, we found the paired ones in retrospective-gating patients database and randomly selected one patient in these match cases and built up the RGH group. Image quality for all coronary segments was assessed and compared between the two groups using a 4-point scale (1: non-diagnostic; 4: excellent). Effective radiation doses were also compared. The average heart rate ± standard deviation (HR ± SD) between the two groups was not significantly different (PGT: 64.6 ± 12.9 bpm, range 45–97 bpm; RGH: 66.7 ± 10.9 bpm, range 48–97 bpm, P = 0.22). A receiver-operating characteristic (ROC) analysis determined a cutoff HR of 75 bpm up to which diagnostic image quality could be achieved using the PGT technique (P < 0.001). There were no significant differences in assessable coronary segments between the two groups for HR ≤ 75 bpm (PGT: 99.9% [961 of 962 segments]; RGH: 99.8% [1038 of 1040 segments]; P = 1.0). At HR > 75 bpm, the performance of the PGT technique was affected, resulting in a moderate reduction of percentage assessable coronary segments using this approach (PGT: 95.5% [323 of 338 segments]; RGH: 98.5% [261 of 265 segments]; P = 0.04). The mean estimated effective radiation dose for the PGT group was 3.0 ± 0.7 mSv, representing reduction of 73% compared to that of the RGH group (11.1 ± 1.6 mSv) (P < 0.001). Prospectively-gated axial coronary computed tomography using a 256-slice multidetector CT scanner with a 270 ms tube rotation time enables a significant reduction in effective radiation dose while simultaneously providing image quality comparable to the retrospectively gated helical technique. Our experience demonstrates the applicability of this technique over a wider range of heart rates (up to 75 bpm) than previously reported.     

Magnetic resonance imaging of coronary artery occlusions in the navigator technique

Non-invasive assessment of coronary arteries is possible with magnetic resonance imaging (MRI). Respiratory gated MR coronary angiography is a new imaging technique that permits reconstruction of the coronary arteries based on a three-dimensional (3D) data set obtained from the free-breathing patient. In this study, respiratory gated MR angiography (MRA) was performed to assess coronary artery occlusions. MRI was performed in 25 patients who had been referred for conventional coronary angiography because of suspected coronary artery disease. Coronary artery occlusion was evaluated in the proximal and middle vessel segments after multiplanar coronary reconstruction of the MR images. Five patients were excluded from the study; in the remaining 20 patients 120 coronary artery segments were analyzed. Good image quality could be obtained for 85% of the segments. Eighteen of the 24 occlusions were confirmed by MRI, the overall sensitivity was 75% and the specificity was 100%. The best results were found in the proximal left anterior descending (LAD) and descending parts of the right coronary artery (RCA), where all occlusions were confirmed. These results showed that coronary artery occlusions can be detected in the proximal and middle LAD and RCA using 3D respiratory gated MRA. Further technical improvements, especially in spatial resolution, are necessary before MRA can become a reliable diagnostic tool in the non-invasive evaluation of coronary arteries.     

The composition and extent of coronary artery plaque detected by multislice computed tomographic angiography provides incremental prognostic value in patients with suspected coronary artery disease

Multislice computed tomographic coronary angiography (CTCA) provides accurate noninvasive assessment of coronary artery disease (CAD). However, data on the prognostic value of CTCA in patients with suspected CAD are only beginning to emerge. The aim of the study was to assess the prognostic value of CTCA in patients with suspected CAD. Patients (males = 259, females = 235; mean age 58.2 ± 9.8 years) with suspected CAD who underwent 16- or 64-slice CTCA were followed for 1,308 ± 318 days for cardiac death, nonfatal myocaridal infarction (MI) and late (>90 days after CTCA) revascularization. Patient outcomes were related to clinical and CTCA data. Cox proportional-hazards model was applied in stepwise forward fashion to identify outcome predictors. Coronary artery plaque was found in 340 patients. Cardiac events occurred in 40 patients including cardiac death (n = 9), nonfatal MI (n = 8) and late revascularization (n = 23). A multivariable analysis identified the following independent predictors for adverse cardiac events: obstructive plaque in a proximal coronary artery segment (hazard ratio (HR) 2.73; 95% confidence interval (CI): 1.35–5.54; P = 0.005), the number of segments with noncalcified plaque(s) (HR 1.53 per segment; 95%CI: 1.21–1.92; P < 0.001), the number of segments with mixed plaque(s) (HR 1.56 per segment; 95%CI: 1.27–1.92; P < 0.001) and the number of segments with calcified plaque(s) (HR 1.21 per segment; 95%CI: 1.07–1.37; P = 0.002). In patients with suspected CAD, both the extent and composition of atherosclerotic plaque as determined by CTCA are prognostic of subsequent cardiac events.     

Screening for proximal coronary artery anomalies with 3-dimensional MR coronary angiography

Under 35 years of age, 14% of sudden cardiac death in athletes is caused by a coronary artery anomaly (CAA). Free-breathing 3-dimensional magnetic resonance coronary angiography (3D-MRCA) has the potential to screen for CAA in athletes and non-athletes as an addition to a clinical cardiac MRI protocol. A 360 healthy men and women (207 athletes and 153 non-athletes) aged 18–60 years (mean age 31 ± 11 years, 37% women) underwent standard cardiac MRI with an additional 3D-MRCA within a maximum of 10 min scan time. The 3D-MRCA was screened for CAA. A 335 (93%) subjects had a technically satisfactory 3D-MRCA of which 4 (1%) showed a malignant variant of the right coronary artery (RCA) origin running between the aorta and the pulmonary trunk. Additional findings included three subjects with ventral rotation of the RCA with kinking and possible proximal stenosis, one person with additional stenosis and six persons with proximal myocardial bridging of the left anterior descending coronary artery. Coronary CT-angiography (CTA) was offered to persons with CAA (the CAA was confirmed in three, while one person declined CTA) and stenosis (the ventral rotation of the RCA was confirmed in two but without stenosis, while two people declined CTA). Overall 3D MRCA quality was better in athletes due to lower heart rates resulting in longer end-diastolic resting periods. This also enabled faster scan sequences. A 3D-MRCA can be used as part of the standard cardiac MRI protocol to screen young competitive athletes and non-athletes for anomalous proximal coronary arteries.     

Prognostic value of dual-source multidetector computed tomography coronary angiography in patients with stent implantation

We aim to evaluate the prognostic value of dual-source 64-slice multidetector computed tomography (MDCT) in patients with coronary stents. The study included 173 patients [mean age 59.9 ± 10.1 years, 76.7 % male] with previous stent implantation who underwent MDCT for evaluation of CAD and stent patency. Coronary imaging was performed via dual-source MDCT scanner. Stented vessel segment was evaluated as patent without neointimal hyperplasia (NIH), nonobstructive NIH (<50 % luminal narrowing), or obstructive NIH (>50 % luminal narrowing). Patients were evaluated for major cardiovascular events (MACEs) to demonstrate association between stent patency and clinical outcome. MACEs that were originating from non-stented segments were excluded. A total of 213 coronary stents were evaluated in our study. During mean of 21.2 ± 13.6 months’ follow-up, 25 patients experienced MACEs [1 (4.0 %) cardiac death, 5 (20.0 %) nonfatal MI, and 19 (76.0 %) unstable angina pectoris requiring hospitalization and target vessel revascularization] associated with stented segment of coronary arteries. One hundred of 105 patients (95.2 %) with a patent stent without NIH detected by MDCT had no cardiac event associated with stented segments during mean 2 years’ follow-up period. These data indicate that patients with a patent stent without NIH as determined by MDCT have a good prognosis as opposed to an increased rate of events among patients with either nonobstructive or obstructive NIH as determined with MDCT, supporting MDCT as a reliable tool to evaluate patients after coronary stenting.