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Cardiac Computed Tomography (cardiac + computed_tomography)
Selected AbstractsFontan Operation and the Single VentricleCONGENITAL HEART DISEASE, Issue 1 2007Jamil A. AboulHosn MD ABSTRACT The Fontan operation has gone through multiple incarnations since Fontan and Baudet's initial description in 1971. Through the medical dossier of a patient with a single ventricle, we plot the history of medical, surgical, and percutaneous interventions over the past 40 years, specifically focusing on the Fontan procedure, its development, indications, sequelae, and complications. Cardiac computed tomography with angiography is highlighted as a noninvasive imaging tool for the evaluation of the complex Fontan circulation. [source] Cardiac computed tomography: Diagnostic utility and integration in clinical practiceCLINICAL CARDIOLOGY, Issue S1 2006Matthew J. Budoff M.D. Abstract Cardiac applications of computed tomography (CT) is a rapidly growing diagnostic area because of the ability to visualize plaque burden (coronary artery calcification [CAC]) and luminal obstruction (computed tomographic angiography [CTA]) noninvasively. Coronary artery calcification has been validated in over 1,000 studies over the last 20 years, primarily with electron beam tomography. Studies demonstrate several indications that could aid physicians in the management of symptomatic and asymptomatic patients. Determining that a symptomatic patient has no CAC is associated with both a lower risk of an abnormal nuclear study and angiographic obstruction. The ability to detect subclinical atherosclerosis (CAC) with minimal radiation and no contrast makes this an attractive method for risk stratification. New studies demonstrate a 10-fold risk of cardiovascular events with increasing amounts of coronary calcification. The invasive nature, expense, and risk resulting from invasive angiography have been instrumental in encouraging the development of new diagnostic methods that allow the coronary arteries to be visualized noninvasively. Multislice CT, with its advanced spatial and temporal resolution, has opened up new possibilities in the imaging of the heart and major vessels of the chest, including the coronary arteries. The last decade has seen great strides in the field of cardiac imaging, particularly in the ability to visualize the coronary lumen with sufficient diagnostic accuracy. Possessing that qualification, CTA is now being used increasingly in clinical practice. As a result of having high spatial and improved temporal resolutions, this imaging modality not only allows branches of the coronary artery to be evaluated, but also allows simultaneous analysis of other cardiac structures, making it extremely useful for other cardiac applications. This paper reviews the diagnostic utility and limitations of cardiac CT and how it could be integrated into clinical practice. [source] Refractory Progression of Coronary Aneurysms, a Case of Delayed Onset Kawasaki Disease as Depicted by Cardiac Computed Tomography AngiographyCONGENITAL HEART DISEASE, Issue 3 2010FACP, Shah Azmoon MD ABSTRACT Background., Kawasaki disease (KD) is an immune-mediated vasculitis of unknown etiology with self-limited clinical course that was first described in 1967 by Dr. Tomisaku Kawasaki. It is a disease of early childhood and rare past late adulthood but one that can have detrimental consequences when there is a delay in diagnosis and treatment. Cardiovascular complications causing increased morbidity and mortality may include coronary artery aneurysms, myocardial infarction, heart failure, arrhythmias, and peripheral artery occlusion. Case Presentation., Here, we present an atypical case of delayed onset KD in a young teenager. DS had visited three different emergency departments during the course of 2 weeks for unrelenting fevers. Despite multiple treatment protocols including immunoglobulin, steroids, and tumor necrosis factor-alpha antagonists, he continued to have progression of cardiovascular complications. While echocardiographic findings were suspicious for cardiac complications, a cardiac computed tomography (CT) angiography was able to clearly distinguish giant coronary aneurysms. Conclusion., Without prompt therapy, fever and manifestations of acute inflammation can last for several weeks to months with increased risk toward complications. The incidence of coronary artery aneurysms has been noted to be 25% in untreated patients with a mortality rate of up to 2%. Using low-dose protocols along with high spatial and temporal resolution of cardiac CT angiography may provide a useful and complimentary imaging modality in accurate diagnosis and follow-up of patients with KD. [source] A comparative study on interpolation methods for controlled cardiac CTINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 2 2007Deepak Bharkhada Abstract Bai et al. recently proposed to acquire random fan-beam/cone-beam projections with a linear/planar detector from a circular scanning locus for controlled cardiac computed tomography (CT). After specifying a uniform acquisition geometry required by FBP (filtration-backprojection), we rebin the random fan-beam/cone-beam data via nearest-neighbor, quadrilateral and triangle-based linear interpolation methods. The fan-beam and parallel-beam FBP algorithms are employed for rebinned fan-beam projections. The FDK (Feldkamp,Davis,Kress) and t-FDK (tent-FDK) methods are employed for rebinned cone-beam data. Also, nonuniform weighting fan-beam/FDK methods are used to reconstruct without rebinning. As a benchmark, the images are reconstructed using uniform weighting fan-beam/FDK method from data collected at the specified uniform grid. To evaluate the different methods, effects of increasing the number of projections and adding Poisson noise are studied. The root mean square error (RMSE) is used to quantify the image quality by numerical tests with the cardiac phantom. Our results show that it is helpful to perform data interpolation for improvements of the image quality in controlled cardiac CT from random projections. Our simulations indicate that triangular interpolation gives the most satisfactory result for improved image quality whereas quadrilateral interpolationgives the best noise performance. © 2007 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 17, 91,98, 2007 [source] Left main coronary artery compression from pulmonary artery enlargement due to pulmonary hypertension: A contemporary review and argument for percutaneous revascularization,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 4 2010Michael S. Lee MD Abstract Extrinsic compression of the left main coronary artery by an enlarged pulmonary artery is an increasingly recognized and potentially reversible cause of angina and left ventricular dysfunction in patients with pulmonary hypertension. The diagnosis of extrinsic left main coronary artery compression requires a high index of suspicion and should be considered in patients with severe pulmonary hypertension who experience angina. Coronary angiography with intravascular ultrasound is the gold standard for diagnosis of this condition, though cardiac computed tomography and magnetic resonance angiography allow for noninvasive means of screening. The optimal treatment is debatable, but percutaneous coronary intervention appears to be a feasible, safe, and effective treatment option for patients with extrinsic compression of the left main coronary artery from pulmonary artery enlargement. Given the high risk of postoperative right ventricular failure and mortality observed with surgical revascularization in these patients, we recommend that physicians recognize percutaneous coronary intervention as the preferred revascularization strategy for selected patients with extrinsic compression of the left main coronary artery due to pulmonary hypertension. © 2010 Wiley-Liss, Inc. [source] |