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Phase contrast Magnetic aortic

Pouya Youssefi, Alberto Gomez, Taigang He, Lisa Anderson, Nick Bunce, Rajan Sharma, C Alberto Figueroa, Marjan Jahangiri
OBJECTIVES: The complexity of aortic disease is not fully exposed by aortic dimensions alone, and morbidity or mortality can occur before intervention thresholds are met. Patient-specific computational fluid dynamics (CFD) were used to assess the effect of different aortic valve morphologies on velocity profiles, flow patterns, helicity, wall shear stress (WSS), and oscillatory shear index (OSI) in the thoracic aorta. METHODS: A total of 45 subjects were divided into 5 groups: volunteers, aortic regurgitation-tricuspid aortic valve (AR-TAV), aortic stenosis-tricuspid aortic valve (AS-TAV), aortic stenosis-bicuspid aortic valve right-left cusp fusion (BAV[RL]), and aortic stenosis-right-non cusp fusion (AS-BAV[RN])...
September 23, 2016: Journal of Thoracic and Cardiovascular Surgery
Litten Bertelsen, Jesper Hastrup Svendsen, Lars Køber, Ketil Haugan, Søren Højberg, Carsten Thomsen, Niels Vejlstrup
BACKGROUND: Cardiovascular magnetic resonance (CMR) is considered the gold standard of cardiac volumetric measurements. Flow in the aortic root is often measured at the sinotubular junction, even though placing the slice just above valve level may be more precise. It is unknown how much flow measurements vary at different levels in the aortic root and which level corresponds best to left ventricle volumetry. METHODS: All patients were older than 70 years presenting with at least one of the following diagnoses: diabetes, hypertension, prior stroke and/or heart failure...
September 7, 2016: Journal of Cardiovascular Magnetic Resonance
Hojin Ha, Guk Bae Kim, Jihoon Kweon, Sang Joon Lee, Young-Hak Kim, Namkug Kim, Dong Hyun Yang
Since the first observation of a helical flow pattern in aortic blood flow, the existence of helical blood flow has been found to be associated with various pathological conditions such as bicuspid aortic valve, aortic stenosis, and aortic dilatation. However, an understanding of the development of helical blood flow and its clinical implications are still lacking. In our present study, we hypothesized that the direction and angle of aortic inflow can influence helical flow patterns and related hemodynamic features in the thoracic aorta...
2016: Scientific Reports
Jehill D Parikh, Kieren G Hollingsworth, Dorothy Wallace, Andrew M Blamire, Guy A MacGowan
BACKGROUND: In normal ageing, both vascular and ventricular properties change, and how these affect left ventricular function is not clear. METHODS: 96 subjects (ages 20-79) without cardiovascular disease underwent cardiac magnetic resonance (MR) imaging for measurement of global function, diastolic function (E/A ratio), MR tagging for measurement of torsion to shortening ratio (TSR, ratio of epicardial torsion to endocardial circumferential shortening, with increase in TSR suggesting subendocardial dysfunction relative to the subepicardium), and phase contrast MR imaging measurement of central aortic pulse wave velocity (PWV)...
November 15, 2016: International Journal of Cardiology
M Cecelja, T Hussain, M Silva Vieira, A Phinikaridou, G Greil, T Spector, P Chowienczyk
OBJECTIVE: Vascular aging is characterised by structural changes: wall thickening and change in lumen diameter, together with functional changes in aortic stiffness. We investigated the longitudinal structural and functional changes that occur in the aortic wall over a 4 year follow-up period. DESIGN AND METHOD: Magnetic resonance imaging (MRI) was performed in 38 asymptomatic women aged between 53-73 years at baseline and 4 years later over from the aortic arch to aortic bifurcation...
September 2016: Journal of Hypertension
Henrique B Ribeiro, Stefan Orwat, Salim S Hayek, Éric Larose, Vasilis Babaliaros, Abdellaziz Dahou, Florent Le Ven, Sergio Pasian, Rishi Puri, Omar Abdul-Jawad Altisent, Francisco Campelo-Parada, Marie-Annick Clavel, Philippe Pibarot, Stamatios Lerakis, Helmut Baumgartner, Josep Rodés-Cabau
BACKGROUND: Residual aortic regurgitation (AR) following transcatheter aortic valve replacement (TAVR) is associated with greater mortality; yet, determining AR severity post-TAVR using Doppler echocardiography remains challenging. Cardiovascular magnetic resonance (CMR) is purported as a more accurate means of quantifying AR; however, no data exist regarding the prognostic value of AR as assessed by CMR post-TAVR. OBJECTIVES: This study sought to evaluate the effect of AR assessed with CMR on clinical outcomes post-TAVR...
August 9, 2016: Journal of the American College of Cardiology
Thekla H Oechtering, Carl F Hons, Malte Sieren, Peter Hunold, Anja Hennemuth, Markus Huellebrand, Johann Drexl, Michael Scharfschwerdt, Doreen Richardt, Hans-Hinrich Sievers, Jörg Barkhausen, Alex Frydrychowicz
OBJECTIVE: The anatomically shaped sinus prosthesis (Uni-Graft W SINUS; Braun, Melsungen, Germany) used in valve-sparing aortic root replacement promises physiological hemodynamics believed to grant physiologic valve function. Using time-resolved 3-dimensional magnetic resonance phase contrast imaging (4D Flow MRI), we analyzed sinus vortex formation and transvalvular pressure gradients in patients with sinus prosthesis compared with age-matched and young healthy volunteers. METHODS: Twelve patients with sinus prosthesis (55 ± 15 years), 12 age-matched and 6 young healthy volunteers (55 ± 6 years, 25 ± 3 years, respectively) were examined at 3T with a 4D flow magnetic resonance imaging sequence...
August 2016: Journal of Thoracic and Cardiovascular Surgery
Karolina Dorniak, Einar Heiberg, Marcin Hellmann, Dorota Rawicz-Zegrzda, Maria Wesierska, Rafal Galaska, Agnieszka Sabisz, Edyta Szurowska, Maria Dudziak, Erik Hedström
BACKGROUND: Pulse wave velocity (PWV) is a biomarker for arterial stiffness, clinically assessed by applanation tonometry (AT). Increased use of phase-contrast cardiac magnetic resonance (CMR) imaging allows for PWV assessment with minor routine protocol additions. The aims were to investigate the acquired temporal resolution needed for accurate and precise measurements of CMR-PWV, and develop a tool for CMR-PWV measurements. METHODS: Computer phantoms were generated for PWV = 2-20 m/s based on human CMR-PWV data...
2016: BMC Cardiovascular Disorders
Hans-Josef Feistritzer, Gert Klug, Sebastian J Reinstadler, Martin Reindl, Agnes Mayr, Michael Schocke, Bernhard Metzler
OBJECTIVES: Measurement of aortic pulse wave velocity (PWV) is the gold standard for assessment of aortic stiffness. In patients with ST-segment elevation myocardial infarction (STEMI), high aortic PWV has deleterious effects on the myocardium. In the present study, we compared a novel oscillometric device with cardiac magnetic resonance (CMR) imaging for the assessment of aortic PWV in STEMI patients. METHODS: We measured aortic PWV in 60 reperfused STEMI patients using two different methods...
September 2016: Journal of Hypertension
Yoshiaki Ohyama, Bharath Ambale-Venkatesh, Chikara Noda, Atul R Chugh, Gisela Teixido-Tura, Jang-Young Kim, Sirisha Donekal, Kihei Yoneyama, Ola Gjesdal, Alban Redheuil, Chia-Ying Liu, Tetsuya Nakamura, Colin O Wu, W Gregory Hundley, David A Bluemke, Joao A C Lima
BACKGROUND: This study sought to assess cross-sectional associations of aortic stiffness assessed by magnetic resonance imaging with left ventricular (LV) remodeling and myocardial deformation in the Multi-Ethnic Study of Atherosclerosis (MESA). METHODS AND RESULTS: Aortic arch pulse wave velocity (PWV) was measured with phase contrast cine magnetic resonance imaging. LV circumferential strain (Ecc), torsion, and early diastolic strain rate were determined by tagged magnetic resonance imaging...
July 2016: Circulation. Cardiovascular Imaging
Ali Ayaon-Albarran, Rodrigo Fernandez-Jimenez, Jacobo Silva-Guisasola, Jaume Agüero, Javier Sanchez-Gonzalez, Carlos Galan-Arriola, Fernando Reguillo-Lacruz, Luis C Maroto Castellanos, Borja Ibanez
OBJECTIVES: The impact of systolic flow displacement on the development and progression of ascending aorta dilatation in aortic valve disease is a matter of controversy. Our objective was to study the association between rheological stimuli and development of aortic dilatation in a large animal model of supravalvular aortic stenosis and eccentric flow. METHODS: Twenty-four pigs weighing 10-14 kg were randomly allocated (ratio 2:1) to either restrictive ascending aortic banding or sham operation...
October 2016: European Journal of Cardio-thoracic Surgery
Michael J Rose, Kelly Jarvis, Varun Chowdhary, Alex J Barker, Bradley D Allen, Joshua D Robinson, Michael Markl, Cynthia K Rigsby, Susanne Schnell
PURPOSE: To test the feasibility and effectiveness of using maximum intensity plots (MIPs) based on 4D flow magnetic resonance imaging (MRI) velocity data to assess systolic peak velocities in a cohort of bicuspid aortic valve (BAV) patients. MATERIALS AND METHODS: 4D flow MRI at 1.5T was performed on 51 BAV patients. MIPs were generated from the 4D flow MRI velocity data and used by two users to determine peak velocities in three regions of interest (ROIs): ascending aorta (AAo), aortic arch, and descending aorta...
December 2016: Journal of Magnetic Resonance Imaging: JMRI
Dimitrios Maragiannis, Matthew S Jackson, Jose H Flores-Arredondo, Kyle Autry, Robert C Schutt, Paulino A Alvarez, William A Zoghbi, Dipan J Shah, Stephen H Little
OBJECTIVES: The aim of this study was to evaluate cardiac magnetic resonance (CMR) phase-contrast (PC) measures of a bioprosthetic aortic valve velocity time integral (PC-VTI) to derive the effective orifice area (PC-EOA) and to compare these findings with the clinical standard of Doppler echocardiography. BACKGROUND: Bioprosthetic aortic valve function can be assessed with CMR planimetry of the anatomic orifice area and PC measurement of peak transvalvular systolic velocity...
July 2016: JACC. Cardiovascular Imaging
Fabian Kording, Jin Yamamura, Gunnar Lund, Friedrich Ueberle, Caroline Jung, Gerhard Adam, Bjoern Philip Schoennagel
PURPOSE: Electrocardiogram (ECG) triggering for cardiac magnetic resonance (CMR) may be influenced by electromagnetic interferences with increasing magnetic field strength. The aim of this study was to evaluate the performance of Doppler ultrasound (DUS) as an alternative trigger technique for CMR in comparison to ECG and pulse oximetry (POX) at 3T and using different sequence types. METHODS: Balanced turbo field echo two-dimensional (2D) short axis cine CMR and 2D phase-contrast angiography of the ascending aorta was performed in 11 healthy volunteers at 3T using ECG, DUS, and POX for cardiac triggering...
March 21, 2016: Magnetic Resonance in Medical Sciences: MRMS
Hojin Ha, Guk Bae Kim, Jihoon Kweon, Hyung Kyu Huh, Sang Joon Lee, Hyun Jung Koo, Joon-Won Kang, Tae-Hwan Lim, Dae-Hee Kim, Young-Hak Kim, Namkug Kim, Dong Hyun Yang
BACKGROUND: Although the measurement of turbulence kinetic energy (TKE) by using magnetic resonance imaging (MRI) has been introduced as an alternative index for quantifying energy loss through the cardiac valve, experimental verification and clinical application of this parameter are still required. OBJECTIVES: The goal of this study is to verify MRI measurements of TKE by using a phantom stenosis with particle image velocimetry (PIV) as the reference standard...
2016: PloS One
Jesús Urbina, Julio A Sotelo, Daniel Springmüller, Cristian Montalba, Karis Letelier, Cristián Tejos, Pablo Irarrázaval, Marcelo E Andia, Reza Razavi, Israel Valverde, Sergio A Uribe
PURPOSE: To design and characterize a magnetic resonance imaging (MRI)-compatible aortic phantom simulating normal and aortic coarctation (AoCo) conditions and to compare its hemodynamics with healthy volunteers and AoCo patients. MATERIALS AND METHODS: The phantom is composed of an MRI-compatible pump, control unit, aortic model, compliance chamber, nonreturn, and shutoff valves. The phantom without and with AoCo (13, 11, and 9 mm) was studied using 2D and 3D phase-contrast data and with a catheterization unit to measure pressures...
September 2016: Journal of Magnetic Resonance Imaging: JMRI
Kristine Skårdal, Emil K S Espe, Lili Zhang, Jan Magnus Aronsen, Ivar Sjaastad
PURPOSE: Determination of mitral flow is an important aspect in assessment of cardiac function. Traditionally, mitral flow is measured by Doppler echocardiography which suffers from several challenges, particularly related to the direction and the spatial inhomogeneity of flow. These challenges are especially prominent in rodents. The purpose of this study was to establish a cardiovascular magnetic resonance (CMR) protocol for evaluation of three-directional mitral flow in a rodent model of cardiac disease...
2016: PloS One
Carsten Rickers, Arash Kheradvar, Hans-Hinrich Sievers, Ahmad Falahatpisheh, Philip Wegner, Dominik Gabbert, Michael Jerosch-Herold, Chris Hart, Inga Voges, Léon M Putman, Ines Kristo, Gunther Fischer, Jens Scheewe, Hans-Heiner Kramer
OBJECTIVES: To compare the Lecompte technique and the spiral anastomosis (complete anatomic correction) two decades after arterial switch operation (ASO). METHODS: Nine patients after primary ASO with Lecompte and 6 selected patients after spiral anastomosis were evaluated 20.8 ± 2.1 years after ASO versus matched controls. Blood flow dynamics and flow profiles (e.g. vorticity, helicity) in the great arteries were quantified from time-resolved 3D magnetic resonance imaging (MRI) phase contrast flow measurements (4D flow MR) in addition to a comprehensive anatomical and functional cardiovascular MRI analysis...
June 2016: Interactive Cardiovascular and Thoracic Surgery
Zhenglun Wei, Kevin K Whitehead, Reza H Khiabani, Michael Tree, Elaine Tang, Stephen M Paridon, Mark A Fogel, Ajit P Yoganathan
BACKGROUND: It is known that respiration modulates cavopulmonary flows, but little data compare mean flows under breath-holding and free-breathing conditions to isolate the respiratory effects and effects of exercise on the respiratory modulation. METHODS: Real-time phase-contrast magnetic resonance combined with a novel method to track respiration on the same image acquisition was used to investigate respiratory effects on Fontan caval and aortic flows under breath-holding, free-breathing, and exercise conditions...
May 2016: Annals of Thoracic Surgery
Laleh Zarrinkoob, Khalid Ambarki, Anders Wåhlin, Richard Birgander, Bo Carlberg, Anders Eklund, Jan Malm
Excessive pulsatile flow caused by aortic stiffness is thought to be a contributing factor for several cerebrovascular diseases. The main purpose of this study was to describe the dampening of the pulsatile flow from the proximal to the distal cerebral arteries, the effect of aging and sex, and its correlation to aortic stiffness. Forty-five healthy elderly (mean age 71 years) and 49 healthy young (mean age 25 years) were included. Phase-contrast magnetic resonance imaging was used for measuring blood flow pulsatility index and dampening factor (proximal artery pulsatility index/distal artery pulsatility index) in 21 cerebral and extra-cerebral arteries...
September 2016: Journal of Cerebral Blood Flow and Metabolism
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