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Accuracy of MSCT Coronary Angiography with 64 Row CT Scanner—Facing the Facts
M. Wehrschuetz, E. Wehrschuetz, H. Schuchlenz and G. Schaffler
Clinical Medicine Insights: Cardiology , 2012, DOI: 10.4137/CMC.S3864
Abstract: Improvements in multislice computed tomography (MSCT) angiography of the coronary vessels have enabled the minimally invasive detection of coronary artery stenoses, while quantitative coronary angiography (QCA) is the accepted reference standard for evaluation thereof. Sixteen-slice MSCT showed promising diagnostic accuracy in detecting coronary artery stenoses haemodynamically and the subsequent introduction of 64-slice scanners promised excellent and fast results for coronary artery studies. This prompted us to evaluate the diagnostic accuracy, sensitivity, specificity, and the negative und positive predictive value of 64-slice MSCT in the detection of haemodynamically significant coronary artery stenoses. Thirty-seven consecutive subjects with suspected coronary artery disease were evaluated with MSCT angiography and the results compared with QCA. All vessels were considered for the assessment of significant coronary artery stenosis (diameter reduction ≥ 50%). Thirteen patients (35%) were identified as having significant coronary artery stenoses on QCA with 6.3% (35/555) affected segments. None of the coronary segments were excluded from analysis. Overall sensitivity for classifying stenoses of 64-slice MSCT was 69%, specificity was 92%, positive predictive value was 38% and negative predictive value was 98%. The interobserver variability for detection of significant lesions had a -value of 0.43. Sixty-four-slice MSCT offers the diagnostic potential to detect coronary artery disease, to quantify haemodynamically significant coronary artery stenoses and to avoid unnecessary invasive coronary artery examinations.
Accuracy of MSCT Coronary Angiography with 64 Row CT Scanner—Facing the Facts
M. Wehrschuetz,E. Wehrschuetz,H. Schuchlenz,G. Schaffler
Clinical Medicine Insights: Cardiology , 2010,
Abstract: Improvements in multislice computed tomography (MSCT) angiography of the coronary vessels have enabled the minimally invasive detection of coronary artery stenoses, while quantitative coronary angiography (QCA) is the accepted reference standard for evaluation thereof. Sixteen-slice MSCT showed promising diagnostic accuracy in detecting coronary artery stenoses haemodynamically and the subsequent introduction of 64-slice scanners promised excellent and fast results for coronary artery studies. This prompted us to evaluate the diagnostic accuracy, sensitivity, specificity, and the negative und positive predictive value of 64-slice MSCT in the detection of haemodynamically significant coronary artery stenoses. Thirty-seven consecutive subjects with suspected coronary artery disease were evaluated with MSCT angiography and the results compared with QCA. All vessels were considered for the assessment of significant coronary artery stenosis (diameter reduction ≥ 50%). Thirteen patients (35%) were identified as having significant coronary artery stenoses on QCA with 6.3% (35/555) affected segments. None of the coronary segments were excluded from analysis. Overall sensitivity for classifying stenoses of 64-slice MSCT was 69%, specificity was 92%, positive predictive value was 38% and negative predictive value was 98%. The interobserver variability for detection of significant lesions had a -value of 0.43. Sixty-four-slice MSCT offers the diagnostic potential to detect coronary artery disease, to quantify haemodynamically significant coronary artery stenoses and to avoid unnecessary invasive coronary artery examinations.
Comparative Analysis between SPECT Myocardial Perfusion Imaging and CT Coronary Angiography for Diagnosis of Coronary Artery Disease  [PDF]
Jian-ming Li,Ting Li,Rong-fang Shi,Li-ren Zhang
International Journal of Molecular Imaging , 2012, DOI: 10.1155/2012/253475
Abstract: The study aims to discuss the relationship and difference between myocardial perfusion imaging (MPI) using SPECT and CT coronary angiography (CTCA) for diagnosis of coronary artery disease (CAD). Five hundred and four cases undergoing MPI and CTCA were comparatively analyzed, including fifty six patients undergoing invasive coronary angiography in the same period. Among patients with negative MPI results, negative or positive CTCA occupied 84.7% or 15.3%, respectively. Among patients with positive MPI, positive or negative CTCA occupied 67.2% or 32.8%, respectively. Among patients with negative CTCA, negative or positive MPI occupied 94.4% or 5.6%, respectively. Among patients with positive CTCA, positive or negative MPI occupied 40.2% or 59.8%, respectively. Negative predictive value was relatively higher than the positive predictive value for positive CTCA eliminating or predicting abnormal haemodynamics. And there was no significant difference for sensitivity, specificity, and accuracy of MPI or CTCA in diagnosing CAD. Both MPI and CTCA have good diagnostic performance for CAD. They provide different and complementary information for diagnosis and evaluation of CAD, namely, detection of ischemia versus detection of atherosclerosis, which are quite different but have a definite internal link for each other. 1. Introduction Myocardial perfusion imaging (MPI) with single-photon emission computer tomography (SPECT) is the most commonly used and well-documented noninvasive method for diagnosis and risk stratification of coronary artery disease (CAD) [1]. The location and extent of ischemia can be reliably and semiquantitatively obtained using MPI, which plays an important role for patient management. The latest advancements for computed tomography (CT), such as faster gantry, multidetector array, and even dual-source detectors, make it possible to noninvasively and intuitively obtain anatomic morphology of coronary arteries, especially contributing to identifying the magnitude, distribution, and composition of coronary atherosclerosis. It has been documented that CT coronary angiography (CTCA) has high accuracy in detection of obstructive CAD comparing with invasive coronary angiography (ICA) [2]. As noninvasive diagnostic methods of CAD for both MPI and CTCA, how to correctly recognize the respective role and relationship between them in diagnosing and evaluating CAD is a very important question concerned by clinicians. This study aims to discuss and evaluate the relationship and difference between SPECT MPI and CTCA through comparative analysis. 2.
Preliminary Reports on the Accuracy of Coronary CT-Angiography Using 64-slice Multi-slice Spiral CT (MSCT) in Iran
"A. Arjmand Shabestari,M. Mozaffari,M. Tehrai,H. Baharjoo
Iranian Journal of Radiology , 2005,
Abstract: Introduction & Background: Coronary artery disease (CAD) is the leading cause of death in many western countries. Its prevalence and incidence among Irani-ans particularly in the urban areas are increasing. Ac-cording to the newest Tehran annual mortality re-port, the most common cause of death in Tehran is cardiovascular disease. Diagnostic gold standard in CAD is fluoroscopic coronary angiography (FCA) us-ing catheterization. Nevertheless, it is an invasive method and in recent years, some non-invasive or less-invasive imaging modalities such as MRI and CT scans have been used to investigate CAD. One of the most attractive new methods in this regard is Coro-nary CT-Angiography (CCTA), which has gained considerable attention. Multi-slice spiral CT (MSCT) scanners with simultaneous acquisition of multiple (up to 64) slices in less than half a second of gantry rotation time (in our study, 0.33 second), have be-come available, resulting in minimally-invasive coro-nary artery imaging. The purpose of this study is to determine the diagnostic accuracy of a new 64-slice MSCT scanner in the diagnosis of coronary artery and/or bypass grafts occlusion or hemodynamically significant stenosis. Parients & Methods: This investigation is underway in patients undergoing elective FCA. A 64-channel per rotation MSCT scanner (Somatom Sensation 64, Siemens Medical Systems, Forchheim, Germany), with 0.6 mm collimation, 0.33 second gantry rotation time and 120 KVp was used to perform CCTA. Ap-proximately 70-90 mL of a nonionic contrast medium was injected intravenously. All coronary artery seg-ments, according to American Heart Association (AHA) classification & nomenclature system were analyzed. Patients who had undergone previous coronary artery bypass grafts (CABGs), or used coro-nary stents were enrolled in the study, as well. MSCT scans were carried out within 10 days of catheteriza-tion, and the most dramatically stenotic lesions were analyzed in CCTA by a semi-quantitative scale (0= no lesion, I= non-significant lesions with less than 50% diameter reduction stenosis, II= significant lesions with more than 50% diameter reduction stenosis, and N/A= non-assessable lesions). Results: The results of CCTA are being compared with quantitative FCA findings of native coronary arteries as well as bypass grafts (arterial and/or ve-nous) or stents. Here the preliminary results of this comparison, as well as the CCTA accuracy as com-pared with FCA are demonstrated. Conclusion: We are hoping that this modality of di-agnosis would find its way in the field of coronary artery diseas
CT Angiography of the Coronary Arteries
H.Ghanaati,S. Markarian
Iranian Journal of Radiology , 2005,
Abstract: Introduction & Background: Cardiac imaging is currently one the most rapidly advancing fields in clinical cardiology. Continuing technical innovations are expanding the applicability and usefulness of non-invasive imaging modalities such as ultrasound, nuclear imaging, positron emis-sion tomography Magnetic Resonance Imaging and most recently computed tomography (CT). In 1998, the 4-slice spiral CT scanners were introduced with a rotation time of 500ms a collimated detector width varying from 0.5 to 1.25mm. In 2002, the 16-slice spiral CT scanners were first used for coronary imag-ing. The rotation time and some of these scanners is now less than 400ms, the slice thickness varies be-tween 0.5 and 0.75mm, and a complete cardiac scan can be performed in less than 20s. In 2004, 64-slice spiral CT released into the market. Imaging of the heart requires acquisition or image reconstruction that is synchronized to the motion of the heart. Nie-man et al, irrespectively of the image quality, evalu-ated all branches with a minimal luminal diameter of 2.0mm and sensitivity and specificity of 95% and 86% respectively in comparison to angiography.
CT coronary angiography vs. invasive coronary angiography in CHD  [cached]
Vitali Gorenoi,Matthias P. Sch?nermark,Anja Hagen
GMS Health Technology Assessment , 2012,
Abstract: Scientific background: Various diagnostic tests including conventional invasive coronary angiography and non-invasive computed tomography (CT) coronary angiography are used in the diagnosis of coronary heart disease (CHD). Research questions: The present report aims to evaluate the clinical efficacy, diagnostic accuracy, prognostic value cost-effectiveness as well as the ethical, social and legal implications of CT coronary angiography versus invasive coronary angiography in the diagnosis of CHD. Methods: A systematic literature search was conducted in electronic data bases (MEDLINE, EMBASE etc.) in October 2010 and was completed with a manual search. The literature search was restricted to articles published from 2006 in German or English. Two independent reviewers were involved in the selection of the relevant publications. The medical evaluation was based on systematic reviews of diagnostic studies with invasive coronary angiography as the reference standard and on diagnostic studies with intracoronary pressure measurement as the reference standard. Study results were combined in a meta-analysis with 95 % confidence intervals (CI). Additionally, data on radiation doses from current non-systematic reviews were taken into account. A health economic evaluation was performed by modelling from the social perspective with clinical assumptions derived from the meta-analysis and economic assumptions derived from contemporary German sources. Data on special indications (bypass or in-stent-restenosis) were not included in the evaluation. Only data obtained using CT scanners with at least 64 slices were considered. Results: No studies were found regarding the clinical efficacy or prognostic value of CT coronary angiography versus conventional invasive coronary angiography in the diagnosis of CHD. Overall, 15 systematic reviews with data from 44 diagnostic studies using invasive coronary angiography as the reference standard (identification of obstructive stenoses) and two diagnostic studies using intracoronary pressure measurement as the reference standard (identification of functionally relevant stenoses) were included in the medical evaluation. Meta-analysis of the nine studies of higher methodological quality showed that, CT coronary angiography with invasive coronary angiography as the reference standard, had a sensitivity of 96 % (95 % CI: 93 % to 98 %), specificity of 86 % (95 % CI: 83 % to 89 %), positive likelihood ratio of 6.38 (95 % CI: 5.18 to 7.87) and negative likelihood ratio of 0.06 (95 % CI: 0.03 to 0.10). However, due to non-diagnostic CT images
Radiation Dose Estimates in CT Coronary Angiography
Peyman Moghadam shad,Abbas Arjmand Shabestari,Shahram Akhlaghpoor,Mohammadreza Alinaghizadeh
Iranian Journal of Radiology , 2009,
Abstract: "nThe coronary artery disease is a common and major cause of death. Invasive coronary angiography is currently the "gold standard" investigation to detect obstructive coronary artery lesions but carries a small risk of serious complications. "nThe mortality risk of invasive coronary angiography (ICA) is about 0.13% which is approximately twice the risk of multi-detector CT (MDCT) angiography (0.07%). MDCT angiography has enabled the detection of coronary artery disease noninvasively. The measured mean effective dose has been measured to be significantly higher in past studies. MDCT angiography radiation dose was clearly more than that of ICA, which has led to a concern about the increasing use of MDCT angiography. Since there was not any study about the radiation dose in patients doing MDCT angiography in Iran and according to the importance of this subject, we performed a study in 134 patients referred for MDCT angiography of the coronary arteries in one of the biggest MDCT angiography centers, using 64-slice MDCT (SIEMENS SOMATOM Sensation 64). The patients were divided into two groups, with or without a previous history of CABG. Total mean effective dose and CTDI were 15.24 mSv and 51.80 mSv, respectively that were similar to previous studies in other parts of the world. Measured quantities were higher in patients who had a history of CABG (20.92 mSv and 13.99 mSv). Our study shows that if the scanning parameters are adjusted for the patient, the radiation dose could be reduced down to 50%.
Use of low-dose adaptive sequence scan of dual-source CT in coronary angiography for arrhythmia: An preliminary study  [cached]
Yue FENG,Guo-long CAI,Wei LI,Lang HE
Medical Journal of Chinese People's Liberation Army , 2013,
Abstract: Objective  To investigate the application of low-dose adaptive sequence scan of dual-source CT in coronary angiography of patients with arrhythmia, and evaluate its diagnostic accuracy. Methods  One hundred and thirty-four patients with arrhythmia undergoing dual-source CT coronary angiography (CTA) were divided into 2 groups according to the scan mode: patients in group A underwent retrospective ECG-gating helical scanning (n=78); patients in group B received adaptive sequence scanning (n=56). The sensitivity, specificity, and positive and negative predictive values of dual-source CTA were determined by using conventional coronary angiography as the reference standard. The significance of difference between the two groups was analyzed, and the respective radiation dose was also compared. Results  The overall sensitivity, specificity, and positive and negative predictive values was 97.0%, 98.5%, 87.4% and 99.7%, respectively in group A, and 97.0%, 98.8%, 88.9% and 99.7%, respectively, in group B. No statistical difference was found between two groups (P>0.05). The average effective radiation dose was 12.0±3.6mSv in group A, which was significantly higher than that in group B (3.1±0.7mSv, Z=-9.826, P=0.00). Conclusion  Adaptive sequence scan combined with the absolute phase reconstruction in dual-source CT coronary angiography is feasible in patients with arrhythmia in providing good image quality and diagnostic accuracy at a low effective radiation dose.
Extracardiac Findings of Coronary CT Angiography by 64 Slice CT
Mahmood Tehrai,Abbas Arjmand Shabestari,Mansoor Fatehi,Hamidreza Baharjoo
Iranian Journal of Radiology , 2009,
Abstract: "nIntroduction: Although coronary CT angiography is primarily performed to evaluate cardiac vasculature and anatomy, due to the inherent potential of MSCT datasets, it is possible to find extra-cardiac alterations which may be influential in the management of the patient. The purpose of this study is to highlight the role of radiologists in the detection of important extra-cardiac disorders. "nMaterials and Methods: All coronary CT angiographic studies (No. 7437) that have been performed between September 2005 and August 2008 in our department are routinely supplemented by reconstructions aimed for the assessment of thoracic (extra-cardiac) structures and interpretation of these findings is a part of our CCTA reports. Coronary CTA studies were retrospectively reviewed to find the list and frequency of extra-cardiac findings. "nResults: A total number of 649 (8.7%) extra-cardiac findings were detected in CCTA. The findings include infiltration (225), effusion (91), lymphadenopathy (86), mass (66), hernia (65) and emboli (39) and many others such as hepatic or splenic mass lesions, gallstones, adrenal masses, aortic abnormalities, aneurysms, thyroid pathologies and spinal changes. "nConclusion: Extra-cardiac findings are not uncommon in CCTA studies. The radiologists can play a major role in finding important extracardiac alterations in those cases referred mainly for cardiac signs and symptoms and in this way they may improve the management of these patients.
Ditection of coronary artery disease: accuracy of 64- slice computed tomography versus converntional invasive angiography
Kazemi Khaledi A,Taghizadeh M
Tehran University Medical Journal , 2008,
Abstract: "nBackground: Multislice computed tomography (MSCT) is a noninvasive method of detecting coronary artery disease (CAD). The purpose of the present study was to investigate the accuracy of 64-slice MSCT (64-MSCT) in daily practice, without patient selection. "nMethods: Sixty-four consecutive suspected CAD patients underwent both 64-MSCT and quantitative coronary angiography (QCA). The CT system The mean time span between MSCT and QCA was 7.2±3.9 days. For the 64-MSCT, detection or exclusion of CAD, defined as one or more areas of >50% stenosis within major epicardial coronary arteries, the sensitivity, specificity, diagnostic accuracy, positive predictive value (PPV), and negative predictive value (NPV) were evaluated both per patient and per segment. "nResults: Sixty-one of the 64 coronary CT angiograms (95%) were of diagnostic image quality. QCA showed significant CAD in 64% (39/61) of the patients, with the other 36% (22/61) showing nonsignificant disease or no disease. Sensitivity, specificity, accuracy, PPV, and NPV of 64-MSCT per patient were 92%, 86%, 90%, 92% and 96%, respectively. By the per-segment analysis, 695 of 791 coronary artery segments were assessable (88%). Of these, 64-MSCT showed a sensitivity of 80%, specificity of 92%, accuracy of 90%, PPV of 65%, and NPV of 96%, respectively, in detecting CAD. "nConclusions: Both per patient and per segment analyses for coronary 64-MSCT showed a higher diagnostic accuracy than QCA. This suggests 64-MSCT should primarily be used for risk stratification on a per patient basis as a noninvasive gate-keeper diagnostic method.
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