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Valvular Heart Disease and Heart Failure
Published in Andreas P. Kalogeropoulos, Hal A. Skopicki, Javed Butler, Heart Failure, 2023
Kali Polytarchou, Constantina Aggeli
Low-dose dobutamine stress echocardiography (DSE) is an important diagnostic and prognostic tool for the evaluation of patients with low-flow, low-gradient AS and reduced LVEF (Figure 14.2). Aortic valve area projected (AVAproj) can be calculated in cases with disagreement between changes in AVA and mean PG or when SV index does not adequately increase. True severe is the AS with AVAproj <1 cm2. Little evidence exists regarding patients with low-flow, low-gradient AS and preserved LVEF. These patients are elderly, mostly women with small left ventricular chamber size and left ventricular hypertrophy or arterial hypertension.13 Multidetector computed tomography and exercise SE may be useful tools for these patients. Considering the clinical and imaging characteristics in combination with the information derived from exercise SE and calcium score, one can give an accurate answer about the severity of valvulopathy (Table 14.1).
Ménière's Disease
Published in John C Watkinson, Raymond W Clarke, Christopher P Aldren, Doris-Eva Bamiou, Raymond W Clarke, Richard M Irving, Haytham Kubba, Shakeel R Saeed, Paediatrics, The Ear, Skull Base, 2018
To exclude these Ménière-like diseases any diagnostic technique available to the clinician should be used: for example, full clinical examination of the head and neck region (including vestibular examination), liminal and speech audiometry, tympanometry, multidetector computed tomography (CT scan) of the temporal bone (with or without intravenous injection of iodine-containing contrast), MRI of the posterior fossa (with intravenous injection of gadolinium), blood analysis (haematology, thyroid, biochemical and genetic testing). The posterior fossa MRI with intravenous administration of gadolinium is the most sensitive examination to exclude cerebellopontine angle and inner ear pathology (in the absence of any contraindications to MRI).
Imaging of the adrenal glands
Published in Demetrius Pertsemlidis, William B. Inabnet III, Michel Gagner, Endocrine Surgery, 2017
Technological improvements in cross-sectional imaging continue to better define adrenal anatomy and improve characterization of adrenal lesions. Multidetector computed tomography (CT) scanners can produce submillimeter axial slice thickness, and these data are then used to generate a volumetric data set. Images can then be reconstructed in any orientation with isotropic resolution, where resolution is equal in all three dimensions. As the number of CT detectors has increased and the rotation time of the X-ray tube has decreased, scan times have been dramatically diminished to a few seconds. At the same time, newer scanners can accomplish this with a reduced radiation dose by utilizing a technique termed iterative reconstruction. When CT images are acquired using a lower radiation dose, there is a greater amount of image noise present. Iterative reconstruction is an algorithm used to reconstruct two-dimensional (2D) and three-dimensional (3D) images that are relatively insensitive to noise compared with traditional reconstruction techniques. It produces an optimal image, even when the acquired data are incomplete, as occurs in the setting of metal artifact.
Multidetector computed tomography in transcatheter aortic valve replacement: an update on technological developments and clinical applications
Published in Expert Review of Cardiovascular Therapy, 2020
Moshrik Abd Alamir, Salik Nazir, Anas Alani, Ilana Golub, Ian C Gilchrist, Faisal Aslam, Puneet Dhawan, Khalid Changal, Carson Ostra, Ronak Soni, Ahmad Elzanaty, Matthew Budoff
Aortic stenosis is a major health problem that primarily affects the elderly. In North America and Europe, aortic stenosis is primarily due to calcific disease of a native trileaflet valve or a congenitally bicuspid valve. Transcatheter aortic valve replacement (TAVR) has become an important treatment option for patients with severe symptomatic trileaflet aortic stenosis with high and intermediate surgical risk [1,2]. Recent data suggests that it may be considered a treatment option for all subsets of patients with appropriate anatomy and vascular access independent of surgical risk [3,4]. Technical advances and improved learning curves have resulted in superior procedural and mid-term outcomes allowing this therapy to be extended to bicuspid aortic valve, degenerated surgical bioprosthesis (valve-in-valve), and native aortic regurgitation [5–7]. The role of multidetector computed tomography (MDCT) in TAVR has been extensively studied [8–11]. In this review, we discuss an update on the technological developments and clinical applications of MDCT including the procedural protocol, and specific issues related to annulus sizing, coronary obstruction, bicuspid aortic valves and post-TAVR applications.
Technical Considerations and Pitfalls of BASILICA: Bioprosthetic or Native Aortic Scallop Intentional Laceration to Prevent Iatrogenic Coronary Artery Obstruction
Published in Structural Heart, 2020
Ikki Komatsu, Harindra Wijeysandera, Sam Radharkrisnan, Brian Whisenant, Matheus Simonato, Albert Chen, G. Burkhard Mackensen, Mark Reisman, Christian Spies, Kashish Goel, Mohamed Abdel-Wahab, Danny Dvir
Multidetector computed tomography is the primary imaging modality to evaluate the relationship between the aortic valve and the coronary ostia to determine the risk of coronary obstruction. Anatomical characteristics associated with higher risk include low-lying coronary ostia, narrow sinus of Valsalva, and a narrow low sinotubular junction (STJ). A short virtual transcatheter valve to coronary (VTC) distance can predict the risk for coronary obstruction, with some inherent limitations.1,2 Although data from the VIVID registry reveal that VTC<4 mm is associated with high risk of coronary obstruction with high sensitivity and specificity (85% and 89%, respectively), the actual threshold that will put coronary flow at risk also depends on the bulkiness of the deflected leaflet, the magnitude of coronary flow, presence of bypass vessels, and the actual lateral leaflet deflection.1 These parameters are occasionally challenging to predict.2,11
Appropriate endoscopic treatment selection and surveillance for superficial non-ampullary duodenal epithelial tumors
Published in Scandinavian Journal of Gastroenterology, 2021
Kingo Hirasawa, Yuichiro Ozeki, Atsushi Sawada, Chiko Sato, Ryosuke Ikeda, Masafumi Nishio, Takehide Fukuchi, Ryosuke Kobayashi, Makomo Makazu, Masataka Taguri, Shin Maeda
Regardless of complete or incomplete resections, patients without submucosal and/or lymphovascular invasive carcinomas were scheduled for endoscopic follow-up at 2 months after initial treatment, followed by annual tumor marker (carcinoembryonic antigen; CEA and carbohydrate antigen 19-9; CA19-9) checks and endoscopic examinations. If a residual mucosal recurrence was recognized in the scar after initial treatment, a repeat endoscopic treatment was performed. For patients who were histologically diagnosed as having submucosal and/or lymphovascular invasive carcinomas, an additional surgery such as pancreaticoduodenectomy was recommended. Patients who refused an additional surgery underwent multidetector computed tomography every 6 months.