Dual-source Multidetector Computed Tomography Research Articles

Optimizing Identification of Power Injectable Ports on the Scout Images for Multidetector Computed Tomography Procedures.

The objective of this study was to assess the impact of tube voltage and image display on the identification of power ports features on anterior-posterior scout images to inform optimal workflow for multidetector computed tomography (MDCT) examinations. Four ports, representing variable material composition (titanium/silicone), shapes, and computed tomography (CT) markings, were imaged on an adult anthropomorphic chest phantom using a dual-source MDCT at variable peak tube voltages (80, 100, 120, 150, and Sn150 kVp). Images were reviewed at variable image display setting by 5 blinded readers to assess port features of material composition, shape, and text markings as well as overall preferred image quality. Material composition was correctly identified for all ports by all readers across all kilovoltage-peak settings. The identification by shape was more reliable than CT markers for all but one of the ports. CT marker identification was up to 80% for titanium ports at window level settings optimized for metal (window width, 200; window center, -150) and at a soft tissue setting (window width, 400; window center, 40) for silicone ports. Interreader agreement for best image quality per kilovoltage-peak setting was moderate to substantial for 3 ports (k = 0.5-0.62) but only fair for 1 port (k = 0.27). The highest overall rank for image quality was given unanimously to Sn150 kVp for imaging titanium ports and 100 kVp for silicone ports. Power port identification on MDCT scout images can be optimized with modification of MDCT scout acquisition and display settings based on the main port material.

EFFECT OF DIABETES MELLITUS ON GRAFT DISEASE PATTERN AFTER CORONARY ARTERY BYPASS GRAFT SURGERY IN SYMPTOMATIC PATIENTS DETECTED BY MULTI SLICE CORONARY COMPUTED TOMOGRAPHY ANGIOGRAPHY

ABSTRACT Background: Surgical revascularization of the coronary arteries is one of the most frequent surgical procedures performed worldwide. Although the procedure is one of the major successes of modern medicine, it does not treat the disease underlying the symptoms (atherosclerosis), but only the clinical presentation of coronary artery disease. Multi detector computed tomography (MDCT) accuracy in coronary artery bypass grafting (CABG) patency and stenosis assessment is excellent compared with angiography. Its safety advantages have led to rapidly increasing usage in both native and grafted vessel evaluation. Objective: To evaluate the impact of diabetes mellitus on the patency of arterial and venous grafts after coronary artery bypass surgery assessed by multi slice CT coronary angiography. Patients and methods: One hundred post CABG patients were included, and divided into two groups: Group A (sixty diabetic patients) from which thirty two had NIDDM (53.3% of diabetic patients), twenty eight (46.6% of diabetic patients) had IDDM, and group B (forty non diabetic patients). Patients subjected to our study were symptomatic with recurrent typical chest pain or angina equivalent. All included patients had sinus rhythm, heart rate less than 70 bpm, weight less than 150 kg and serum creatinine <1.5 mg/dl. Patients were investigated by Seimens Somatom Definition Flash 64- dual source MDCT at least 12 months after the surgery. Results: The most common risk factor in our studied population was hypertension affecting 55% of studied population followed by smoking which was prevalent at 54% of studied population. Comparison of the number of diseased grafts in the two study groups according to hypertension showed a statistically significant difference in group A (diabetic group). Comparison of the number of diseased grafts in the two study groups according to dyslipidemia showed a statistically significant difference in group A. Comparison of the number of diseased grafts in the two study groups according to smoking showed a statistically significant difference in group B (non- diabetic group). 101 arterial grafts had been evaluated for patency, 96 LIMA and 5 radial arteries. There were 59 LIMA in diabetic patients and 37 LIMA in non-diabetic patients evaluated. There was no statistically significant LIMA occlusion in group A and group B. In our study, 141 venous grafts were evaluated for patency: 83 venous grafts in diabetic patients, and 58 venous grafts in non-diabetic patients. Comparison of the two study groups as regards patency of venous grafts showed a statistically significant in group A , and revealed also more occluded grafts at diabetic group. There was a statistically significant graft occlusion with longer duration of diabetes mellitus and higher glycosylated hemoglobin HbA1c. Conclusion: Multi-slice CT coronary angiography has an important role in evaluation patency of coronary grafts after coronary artery bypass surgery. Graft occlusions were more common among diabetics compared with non-diabetics. Diabetes was associated with lower vein graft patency but similar arterial graft patency in comparison to non-diabetics. Uncontrolled diabetes mellitus and long duration of disease was found to be a significant predictor for graft occlusion.

Whole Body Low Dose Computed Tomography Using Third-Generation Dual-Source Multidetector With Spectral Shaping: Protocol Optimization and Literature Review.

For decades, the main imaging tool for multiple myeloma (MM) patient’s management has been the conventional skeleton survey. In 2014 international myeloma working group defined the advantages of the whole-body low dose computed tomography (WBLDCT) as a gold standard, among imaging modalities, for bone disease assessment and subsequently implemented this technique in the MM diagnostic workflow. The aim of this study is to investigate, in a group of 30 patients with a new diagnosis of MM, the radiation dose (CT dose index, dose-length product, effective dose), the subjective image quality score and osseous/extra-osseous findings rate with a modified WBLDCT protocol. Spectral shaping and third-generation dual-source multidetector CT scanner was used for the assessment of osteolytic lesions due to MM, and the dose exposure was compared with the literature findings reported until 2020. Mean radiation dose parameters were reported as follows: CT dose index 0.3 ± 0.1 mGy, Dose-Length Product 52.0 ± 22.5 mGy*cm, effective dose 0.44 ± 0.19 mSv. Subjective image quality was good/excellent in all subjects. 11/30 patients showed osteolytic lesions, with a percentage of extra-osseous findings detected in 9/30 patients. Our data confirmed the advantages of WBLDCT in the diagnosis of patients with MM, reporting an effective dose for our protocol as the lowest among previous literature findings.

P3734Feasibility of percutaneous pulmonary valve implantation in the native right ventricle outflow tract from in vivo dynamic regional strain analysis

Abstract Background Patients surgically treated for congenital heart disease (e.g., Tetralogy of Fallot) frequently report long-term dysfunctions (i.e., pulmonary stenosis and/or incompetence) of the native right ventricle outflow tract (RVOT). The efficacy of percutaneous pulmonary valve implantation (PPVI) is recognized worldwide; however, the procedure is only feasible in RVOTs with appropriate size and functional substrate. Accordingly, a three-dimensional (3D) and dynamic assessment of the native RVOT function can be crucial to identify patients who can effectively benefit from PPVI, thus avoiding the risk of device embolization or fracture. Purpose We herein exploited an optical flow-based approach to develop a novel 3D framework for the quantitative in vivo assessment of dimension and dynamic changes of the native RVOT throughout the cardiac cycle. PPVI candidates (n=15) with previous surgery of the native RVOT were enrolled to demonstrate the additional contribution of our 3D patient-tailored analysis to the decision-making process. Methods Contrast-enhanced computed tomography (CT) was performed on a 64-slice dual-source multidetector CT system with retrospective ECG-gating. Multi-phase images of the RVOT were acquired at each 10% increment of the cardiac cycle (slice thickness = 1.5mm, increment = 1mm, pixel spacing = 0.35mm). We implemented a dedicated in-house framework, based on the optical flow tracking algorithm, to dynamically follow three anatomical cross-sections (i.e., proximal, mid and distal) of the native RVOT. The time course of area, perimeter and other relevant parameters (e.g., equivalent radius, elliptical ratio) were extracted and both areal (εA) and longitudinal strain (εlong) were computed on each the RVOT tracked cross-section. Maximum regional strain were calculated between the maximum and minimum value over the cardiac cycle. Dynamic changes in CT-derived variables were assessed using analysis of variance (p&lt;0.05, statistically significant). Results All the enrolled anatomies were successfully analysed, locally pinpointing the in vivo pattern of deformation within each 3D RVOT anatomy (a). Anatomical regional RVOT dimensions (p&lt;0.0001) and changes proved to be significantly different (p≤0.0002) throughout the cardiac cycle. In addition, the dysfunctional RVOT anatomy exhibited an irregular pattern of contraction and dilation: maximum regional strains markedly differed between RVOT regions, e.g., comparing the εA between RVOT mid (22.6%) and distal (46.0%) regions. In vivo tracking of RVOT dynamic changes Conclusions The combination of patient-specific in vivo imaging and bioengineering strategies can improve our understanding of RVOT dysfunctions in congenital patients referred to PPVI. Our optical flow-based and clinically-oriented framework can support the patient selection process and the planning of the percutaneous procedure in order to enhance its efficacy and shorten the operating time while improving the patient safety. Acknowledgement/Funding IRCCS Policlinico San Donato is a clinical research hospital partially funded by the Italian Ministry of Health

Image Quality on Dual-energy CTPA Virtual Monoenergetic Images: Quantitative and Qualitative Assessment

This study aims to determine the optimal photon energy for image quality of the pulmonary arteries (PAs) on dual-energy computed tomography (CT) pulmonary angiography (CTPA) utilizing low volumes of iodinated contrast. The study received institutional review board exemption and was Health Insurance Portability and Accountability Act compliant. Adults (n = 56) who underwent dual-energy CTPA with 50-60 cc of iodinated contrast on a third-generation dual-source multidetector CT were retrospectively and consecutively identified. Twelve virtual monoenergetic kiloelectron volt (keV) image data sets (40-150 keV, 10-keV increments) were generated with a second-generation noise-reducing algorithm. Standard regions of interest were placed on main, right, left, and right interlobar pulmonary arteries; pectoralis muscle; and extrathoracic air. Attenuation [mean CT number (Hounsfield unit, HU)], noise [standard deviation (HU)], signal to noise (SNR), and contrast to noise ratio were evaluated. Three blinded chest radiologists rated (from 1 to 5, with 5 being the best) randomized monoenergetic and weighted-average images for attenuation and noise. P <.05 was considered significant. Region of interest mean CT number increased as keV decreased, with 40 keV having the highest value (P < .001). Mean SNR was highest for 40-60 keV (P <.05) (14.5-14.7) and was higher (P <.05) than all remaining energies (90-150 keV) for all vessel regions combined. Contrast to noise ratio was highest for 40 keV (P <.001) and decreased as keV increased. SNR was highest at 60 and 70 keV, only slightly higher than 40-50 keV (P <.05). Reader scores for 40-50 keV were greater than other energies and weighted-average images (P <.05). Kiloelectron volt images of 40-50 keV from the second-generation algorithm optimize attenuation on dual-energy CTPA and can potentially aid in interpretation and avoiding nondiagnostic examinations.

Prevalence and spectrum of coronary artery anomalies in 8021 patients: A single center study in South India

ObjectiveTo identify the prevalence of coronary artery anomalies (CAAs) and their subtypes based on Angelini et al. classification in symptomatic yet stable population of South India using 64- slice dual source multi detector CT coronary angiography (MDCT-CA). MethodsWe retrospectively reviewed reports of 8021 symptomatic patients predominantly South Indians who were referred for CT coronary angiography (CT-CA) to our tertiary cardiac care center in Hyderabad, India from January 2011 to March 2017. ResultsWe identified a total of 838 coronary artery anomalies in 812 patients with a prevalence of 10.09%. 96.9% of patients were older than 30 years of age with a M:F ratio of 1.39:1. Coronary artery disease (CAD) was seen in 61.5% of these patients. Among these anomalies, myocardial bridging (MB) was the most common anomaly followed by anomalous location of coronary ostium at improper sinus (ACOIS). ConclusionThere is no significant difference in prevalence of CAAs (including and excluding MB) in Indian and World population. CAAs were more common in males than females and most of these patients remain asymptomatic during first three decades of their life. Myocardial bridging is the most common anomaly detected by MDCT-CA followed by ACOIS. Right coronary artery (RCA) arising from left coronary sinus (LCS) is the most commonly encountered ACOIS.

Segmentations of the cartilaginous skeletons of chondrichthyan fishes by the use of state-of-the-art computed tomography.

AIMTo apply dual-source multidetector computed tomography (DSCT) scanning technology in conjunction with computationally assisted segmentation in order to explore and document skeletal variation that has occurred over the course of evolution.METHODSWe examined 4 divergent species of elasmobranchs with high-resolution 3rd generation DSCT. The formalin prepared species examined were: Aptychotrema vincentiana, Mitsukurina owstoni, Negaprion brevirostris and Dactylobatus armatus.RESULTSAll three structures of the hyoid arch (hyomandibular, ceratohyal, and basihyal) were clearly visible whereas in the two batoids, the hyomandibular was the prominent feature, the ceratohyal was not visible and the basihyal was more reduced and closer to the gill arches. The general shape of the puboischiadic bar, or pelvic girdle, illustrated a closer relationship between the two sharks and the two batoids than between the two groups.CONCLUSIONIn exquisite detail, DSCT imaging revealed important morphological variations in various common structures in the four elasmobranch specimens studied, providing insights into their evolutionary diversification.

Coronary lesion complexity assessed by SYNTAX score in 256-slice dual-source MDCT angiography

The SYNTAX Score (SS) has an important role in grading the complexity of coronary artery disease (CAD) in patients undergoing revascularization. Noninvasive determination of SS prior to invasive coronary angiography (ICA) might optimize patient management. We aimed to evaluate the agreement between ICA and multidetector computed tomography (MDCT) while testing the diagnostic effectiveness of SS-MDCT. Our study included 108 consecutive patients who underwent both MDCT angiography with a 256-slice dual-source MDCT system and ICA within 14±3 days. SS was calculated for both ICA and MDCT coronary angiography. Spearman's rank correlation coefficient was used to evaluate the association of SS-MDCT with SS-ICA, and Bland-Altman analysis was performed. The degree of agreement between SS-ICA and SS-MDCT was moderate. The mean SS-MDCT was 14.5, whereas the mean SS-ICA was 15.9. After dividing SS into three groups (high [≥33], intermediate [23-32], and low [≤22] subgroups), agreement analysis was repeated. There was a significant correlation between SS-MDCT and SS-ICA in the low SS group (r=0.63, P = 0.043) but no significant correlation in the high SS group (r=0.036, P = 0.677). The inter-test agreement analysis showed at least moderate agreement, whereas thrombotic lesions and the type of bifurcation lesion showed fair agreement. The calculation of SS-MDCT by adapting SS-ICA parameters achieved nearly the same degree of precision as SS-ICA and was better than SS-ICA, especially in the low SS group.

Virtual Monochromatic Images from Dual-Energy Multidetector CT: Variance in CT Numbers from the Same Lesion between Single-Source Projection-based and Dual-Source Image-based Implementations.

To determine the variance in virtual monochromatic computed tomography (CT) numbers from the same lesion, comparing the two clinically available dual-energy multidetector CT hardware implementations (single-source projection-based and dual-source image-based), in a phantom-based simulated abdominal environment. This phantom-based study was exempt from institutional review board oversight. Polyethylene terephthalate spheres (15 and 18 mm) with two iodine-to-saline dilutions (0.8 and 1.2 mg of iodine per millilliter) were serially suspended in a cylindrical polypropylene bottle filled with diluted iodinated contrast material. The bottle was placed into a 36-cm-wide torso-shaped water phantom simulating the abdomen of a medium-sized patient. Dual-energy (80/140 kVp) and single-energy (100 and 120 kVp) scans were obtained with single-source and dual-source multidetector CT implementations. Virtual monochromatic images were reconstructed at energy levels of 40-140 keV (in 10-keV increments) in either the projection-space or image-space domain. A multivariate regression analysis approach was used to investigate the effect of energy level, lesion size, lesion iodine content, and implementation type on measured CT numbers. There were significant differences in the attenuation values measured in the simulated lesions with the single-source projection-based platform and the dual-source image-based implementation (P < .001 for all comparisons). The magnitude of these differences was greatest at lower monochromatic energy levels and at lower iodine concentrations (average difference at 40 keV: 25.7 HU; average difference at 140 keV: 7 HU). The monochromatic energy level and the lesion iodine concentration had a significant effect on the difference in the measured attenuation values between the two implementations, which indicates that the two imaging platforms respond differently to changes in investigated variables (P < .001 for all comparisons). There is a statistically significant variance in virtual monochromatic CT numbers from the same lesion examined with single-source projection-based and dual-source image-based implementations. The magnitude of the variance is a function of the selected energy level and the lesion iodine content.

Total Effective Radiation Dose Attributable to Medical Imaging in Patients With Acute Chest Pain: A Single-Center Comparison Study Between Dual-Source Coronary CT Angiography and Usual Care

Introduction: Coronary CT angiography (CCTA) can safely disposition low to intermediate risk chest pain (CP); however, there is conflicting data with respect to cumulative radiation exposure when compared with usual care over short follow-up intervals. Objectives: We report the effective radiation dose from index and downstream testing in low to intermediate risk symptomatic patients evaluated for chest pain in the ED with either CCTA or usual care to define various sources of patient radiation dose and quantify effective dose over a year and a half of follow-up. Patients and Methods: We evaluated radiation exposure from initial and downstream testing in a prospectively collected, matched cohort evaluated for CP in the emergency department (ED) with either CCTA compared with usual care over a median follow-up of 19.6 months. Effective radiation dose was calculated using published conversion factors. Results: Prospective, ECG-triggered acquisition using a 128-slice dual-source multidetector computed tomography (DSCT) scanner was performed in 92.9% of scans with a median effective dose from CCTA of 6.8 mSv (IQR 5.2, 9.1 mSv). CCTA cohort patients were more likely to undergo cardiac testing with exposure to radiation (P < 0.001); however, the median effective dose in patients exposed to radiation from cardiac testing was significantly lower in the CCTA cohort (7.1 mSv vs. 11.8 mSv, P < 0.001). Fewer patients in the CCTA cohort had additional non-cardiac thoracic imaging radiation exposure (40.8%) compared with usual care (92.8%). Total radiation exposure from any source was similar between the CCTA and usual care groups (100% vs 98.4%, P = 0.087), as was median total effective radiation dose (P = 0.105). Upfront CCTA was not associated with higher rates of incidental non-cardiac findings. Conclusions: Initial evaluation of acute chest pain in the ED with CCTA was not associated with an increase in total radiation exposure over a follow-up period of 19 months. CCTA offers a more comprehensive evaluation of multiple thoracic organ systems leading to reduced radiation exposure from non-cardiac thoracic testing and no increase in incidental imaging findings. This may represent an added benefit in this population of patients presenting acutely.

Diagnostic Performance of an Advanced Modeled Iterative Reconstruction Algorithm for Low-Contrast Detectability with a Third-Generation Dual-Source Multidetector CT Scanner: Potential for Radiation Dose Reduction in a Multireader Study.

To assess the effect of radiation dose reduction on low-contrast detectability by using an advanced modeled iterative reconstruction (ADMIRE; Siemens Healthcare, Forchheim, Germany) algorithm in a contrast-detail phantom with a third-generation dual-source multidetector computed tomography (CT) scanner. A proprietary phantom with a range of low-contrast cylindrical objects, representing five contrast levels (range, 5-20 HU) and three sizes (range, 2-6 mm) was fabricated with a three-dimensional printer and imaged with a third-generation dual-source CT scanner at various radiation dose index levels (range, 0.74-5.8 mGy). Image data sets were reconstructed by using different section thicknesses (range, 0.6-5.0 mm) and reconstruction algorithms (filtered back projection [FBP] and ADMIRE with a strength range of three to five). Eleven independent readers blinded to technique and reconstruction method assessed all data sets in two reading sessions by measuring detection accuracy with a two-alternative forced choice approach (first session) and by scoring the total number of visible object groups (second session). Dose reduction potentials based on both reading sessions were estimated. Results between FBP and ADMIRE were compared by using both paired t tests and analysis of variance tests at the 95% significance level. During the first session, detection accuracy increased with increasing contrast, size, and dose index (diagnostic accuracy range, 50%-87%; interobserver variability, ±7%). When compared with FBP, ADMIRE improved detection accuracy by 5.2% on average across the investigated variables (P < .001). During the second session, a significantly increased number of visible objects was noted with increasing radiation dose index, section thickness, and ADMIRE strength over FBP (up to 80% more visible objects, P < .001). Radiation dose reduction potential ranged from 56% to 60% and from 4% to 80% during the two sessions, respectively. Low-contrast detectability performance increased with increasing object size, object contrast, dose index, section thickness, and ADMIRE strength. Compared with FBP, ADMIRE allows a substantial radiation dose reduction while preserving low-contrast detectability. Online supplemental material is available for this article.

Effect of age and plaque morphology on diagnostic accuracy of dual source multidetector computed tomography coronary angiography.

BackgroundMultidetector computed tomography (MDCT) coronary 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. The purpose of this study is to investigate the effect of age and coronary plaque calcification on diagnostic accuracy of MDCT.MethodsThe patients were examined by using dual-source MDCT and conventional coronary angiography. MDCT results were analyzed with regard to the severity (> 50% stenosis) and morphology (non-calcified, mixed, or calcified) of coronary atherosclerotic plaques evaluated in a 16-segment model.ResultsIn total, 181 patients (94 men and 87 women) with 2,687 coronary artery segments were examined with MDCT. Ninety three patients were older than 65 years of age (group A, 42 men) and 88 were younger (group B, 52 men). Two-hundred nine coronary artery segments (7.2%) were excluded because of small distal coronary vessel segments and/or motion artifacts. The overall number of segments with non-diagnostic image quality was similar in both groups of patients. Of the 2,687 evaluated segments, 157 (5.8%) were significantly diseased, and 144 of them were correctly detected by MDCT. Diagnostic evaluation showed that the sensitivity, positive predictive value, specificity, and negative predictive value were 89.5%, 62.5%, 96.0%, and 99.2%, respectively in group A, and 95.2%, 64.8%, 97.5%, and 99.8% in group B, respectively. In addition, detailed segment-based analyses in coronary segments with non-calcified, mixed and calcified plaques in both groups were similar diagnostic accuracy.ConclusionsVery high diagnostic accuracy observed in this study suggests that MDCT coronary angiography could be a suitable diagnostic tool for not only younger patients but also for older patients.

Experience of a single-center in coronary computed tomography angiography

Cardiologia CROATICA Purpose: Coronary computed tomography angiography with calcium scoring measured with Agatston score index provides a diagnosis of coronary atherosclerosis in the patients with subclinical coronary plaque. To evaluate the diagnostic accuracy of Agatston score in comparison with the conventionally used Framingham risk score (FRS) and blood biomarkers in predicting existence of coronary artery disease (CAD) and significant coronary stenosis >50%. Patients and Methods: This retrospective single-center study is evaluating the role of Agatstone score in the prognosis of CAD in patients with previously unknown CAD. 2,597 patients underwent coronary multidetector computed tomography (MDCT) and obtained Agatston score in our Center from June 2012 to April 2014. Scanning was done with dualsource MDCT equipped with two 128-detector row units using the ECG-gating protocol. The mean amount of radiation that was obtained was 6.8 ± 4.5 mSv. The exclusion criteria included Agatston score above 800, atrial fibrillation, pre-existing kidney failure (eGFR 50% or less than 50%. The frequency of demographic and clinical characteristics, blood biomarkers and risk factors were tested between the groups by using chi-squared test and Student T-test as appropriate. To test for factors associated with predicting coronary artery stenosis, likelihood ratio, and receiver operating characteristics analyses were used. Relative risk was calculated in the context of developing coronary artery stenosis greater than 50% in the participants with Agatston score above 100. Results: Out of 2,597 patients participating, 361 patients (mean age 63 ± 8; 227 (63%) of females) with complete data were included in this study. Significant coronary artery stenosis was recorded in 84 (23%) of patients. Mean FRS values were 20 ± 13. Agatstone score (Se 85%, Sp 95%, NPV 95%, PPV 85%, AUC 0.99, 95% CI 0.968 to 1.000, p<0.0001). Conclusion: Among all considered demographic and clinical characteristics, Agatstone score was the most accurate predictor for developing of CAD and significant coronary stenosis.

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.

Diagnostic Accuracy of Dual-Source 64-Slice Multidetector Computed Tomography in Evaluation of Coronary Artery Bypass Grafts

BackgroundThe aim of this study was to compare the diagnostic accuracy of 64-slice multidetector computed tomography (MDCT) with conventional coronary angiography to detect graft patency and stenosis.MethodsIn this retrospective analysis,...

Dual source multidetector computed tomography coronary angiography in the surgical planning regarding the major coronary artery anomalies in children

Background: This study aims to demonstrate major coronary artery anomalies such as anomalous origin and coronary artery fistulas on dual-source multi detector computed tomography (MDCT) coronary angiography in children before surgical treatment. Methods: Six children (3 boys, 3 girls; mean age 6 years; range 2 days to 15 years) referred for a MDCT coronary angiography for evaluation of coronary anomaly between January 2010 and June 2011 were included in this study. Electrocardiography (ECG)-gated dual-source MDCT coronary angiography was performed on all patients. No beta-blockers were given prior to the procedure. The mean heart rate was 98±20 bpm (range 128 to 75 bpm). In all patients, ostium, course, and end-distal portion of coronary artery were inspected for anomalies. Exact opening point was carefully assessed in patients with fistulas. Dual-source MDCT examination was performed with low kilovolt dose reduction algorithm (80 kV, range 150-350 mA) compatible with ALARA principles. Results: Three anomalous origin (one ALCAPA, two anomalous left main coronary artery originated from right sinus of Valsalva) and three fistulas (two coronary-cameral fistula, one left main coronary artery -coronary sinus fistula) were clearly identified with dual-source MDCT angiography. Conclusion: Dual source MDCT angiography is a noninvasive and effective method as an alternative to conventional coronary angiography for the preoperative assessment of major anomalous origin of coronary artery or coronary artery fistulas.

Assessment of the morphological features of degenerative mitral valve disease using 64-slice multi detector computed tomography

Patients with severe mitral regurgitation may be screened for coronary artery disease with the use of cardiac computed tomography before valve surgery. We hypothesized that dual-source multidetector computed tomography (DSCT) could effectively predict the culprit mitral valve scallop identified during surgery among patients with degenerative mitral valve disease undergoing surgical mitral valve repair. Twenty-six patients (7 women) with known severe mitral regurgitation underwent elective mitral valve repair from September 2006 through December 2009 at our institution. An additional 10 patients underwent aortic valve replacement and had no documented history of mitral valve disease. All patients underwent transthoracic echocardiography and had retrospectively gated DSCT performed to evaluate the coronary arteries before surgery. Each mitral scallop was identified as either normal, prolapsed, or flail. CT findings were compared with operative findings, which were guided by intraoperative transesophageal echocardiography (TEE). In the 26 patients examined, DSCT identified flail in 23 scallops and prolapse in 48. DSCT agreed with operative findings on identification of the culprit scallop in 25 of 26 patients. On a per-patient and per-scallop basis, the observed κ statistic for agreement between DSCT and operative findings was 0.82. Of the 60 scallops in the aortic valve group, all were judged to be normal by both DSCT and TEE. In patients with degenerative mitral valve disease undergoing cardiac surgery, DSCT demonstrates excellent agreement with intraoperative findings. DSCT can be used to identify the affected mitral valve scallop and its structure in patients who are candidates for mitral valve repair.

Association of type 2 diabetes mellitus with coronary atherosclerotic plaque burden and morphology measured by multidetector computed tomography coronary angiography

Aims Diabetes mellitus (DM) is strongly associated with increased risk of coronary artery disease (CAD). The aim of this study was to determine differences in presence, extent and morphology of coronary atherosclerotic plaques (CAP) detected by multidetector computed tomography (MDCT) between symptomatic patients with and without diabetes.Methods The CAPs (calcified, non-calcified, mixed) were compared between patients with/without diabetes (104/257 DM; mean age 58.6 ± 11 y; 46.3% male) who underwent dual-source 64-slice MDCT for evaluation of CAD. Severity, extent and morphology of CAPs were determined per each segment.Results Critical coronary stenosis was higher in patients with diabetes (33.7% vs 19.6%) after adjustment for all risk factors (P=0.022). Patients with DM had a higher prevalence and extent of CAP compared to non-diabetic subjects (87.5% vs 43.8%, 4.8 ± 3.5 vs 1.9 ± 2.7, respectively; P < 0.001). Non-calcified and mixed CAP were more prevalent in patients with diabetes as compared to those without diabetes (2.61 ± 2.63 vs 0.86 ± 1.69, 0.81 ± 1.6 vs 0.35 ± 0.96, respectively, P < 0.001). Patients with DM tended to have higher prevalence of significant 1-, 2- and 3-vessel disease (P=0.006).Conclusions Among individuals referred for the evaluation of CAD, those with DM had a higher risk of coronary stenosis and overall increased CAP burden independent from other cardiovascular risk factors shown by MDCT. Further studies are needed to evaluate the prognostic value of different plaque compositions observed in patients with diabetes.

Association between family history of premature coronary artery disease and coronary atherosclerotic plaques shown by multidetector computed tomography coronary angiography

BackgroundThere is controversy regarding the role of family history (FH) of premature coronary artery disease (CAD) as an independent risk factor for CAD. Herein, we aimed to assess the role of FH of premature CAD in prediction of coronary atherosclerosis shown by multidetector computed tomography (MDCT) coronary angiography. MethodsWe analyzed consecutive subset of 349 patients in whom MDCT coronary angiography was performed for suspected CAD. All patients underwent coronary MDCT imaging using dual-source MDCT scanner. Coronary arteries were evaluated on 16-segment basis, critical CAP was described as luminal narrowing >50%, whereas plaque morphology was assessed on per segment basis. ResultsStudy population consisted of 202 (57.9%) male and 147 (42.1%) female patients with mean age of 57.8±10.8years. The presence of CAP was higher in patients with FH of premature CAD in LAD and Cx compared to patients without FH of premature CAD (70.8% vs 58.0%, p=0.013 for LAD; 42.3% vs 30.4%, p=0.021 for Cx; 34.5% vs 29.8%, p=0.348 for RCA).In multinominal logistic regression analysis age, male gender, dyslipidemia and FH of premature CAD seemed significant predictors of primarily noncalcified CAP(OR:1.17, 95% CI:1.07–1.15, p<0.001; OR:0.19, 95% CI:0.09–0.38, p<0.001; OR:2.26, 95% CI:1.21–4.24, p=0.01; OR:3.32, 95% CI:1.74–6.34, p<0.001 respectively) after adjustment for other risk factors. ConclusionOur study results indicate that FH of premature CAD is associated with severity, extent and noncalcified CAP shown by MDCT. Further investigation is needed to clarify the exact diagnostic and prognostic role of MDCT coronary angiography in subjects with positive FH and suspected CAD.

Effectiveness Best R-R Reconstruction Interval Determination Software for the Evaluation of Dual-Source Coronary CT Angiography Examinations

The purpose of this study was to investigate the effectiveness of automated best R-R interval determination software for the evaluation of dual-source coronary multidetector computed tomography (MDCT) angiography. One hundred and nine consecutive patients who underwent dual-source coronary MDCT angiography are included in the study. The indications were chest pain syndrome of low-intermediate risk and/or nonspecific electrocardiographic changes (n = 91), stenting (n = 9), and bypass grafts (n = 9). Imaging was performed using dual-source MDCT. Temporal resolution was 0.83 milliseconds and slice thickness was 0.6 mm. None of the patients received β-blockers. Best R-R interval software has determined the best intervals in diastole and systole. The visibility of coronary arteries was evaluated using 15-segment (total 1635 segments) AHA classification by 2 radiologists in consensus. The mean patient age was 55 years. The mean heart rate was 73 beats per minute (range, 47-110 beats per minute). The mean (SD) best diastole R-R interval was determined as 73 (5) (95% CI, 63-83), and the mean (SD) best systole interval as 38 (5) (95% CI, 28-48). When only best diastole, only best systole, and both best systole and diastole reconstructions were evaluated, all coronary artery segments were visualized in 65 (60%), 61 (56%), and 93 (85%) patients, respectively. In 12 patients' evaluation of additional 1(n = 11) or 2(n = 1), R-R reconstruction intervals allowed visualization of all coronary artery segments. In 4 patients with arrhythmia, all segments cannot be visualized, but after electrocardiographic editing, all segments were visible in 3 of 4 patients. Automatic determination of best R-R reconstruction interval allows evaluation of all coronary artery segments in most patients (85%) without additional reconstructions. By means of this software, coronary CT angiography studies can be evaluated faster and easier. The most significant limitation of the software is patients with arrhythmia.