Magnetic Resonance Imaging of Myocardial Deformation and Scarring in Coronary Artery Disease.

Released on by Johan Kihlberg
preview-18

  • Magnetic Resonance Imaging of Myocardial Deformation and Scarring in Coronary Artery Disease. Book Detail

  • Author : Johan Kihlberg
  • Release Date : 2017-11-15
  • Publisher : Linköping University Electronic Press
  • Genre :
  • Pages : 70
  • ISBN 13 : 9176854310
  • File Size : 11,11 MB
DOWNLOAD BOOK

Magnetic Resonance Imaging of Myocardial Deformation and Scarring in Coronary Artery Disease. by Johan Kihlberg PDF Summary

Book Description: Although improved treatments have reduced the rates of acute complications from myocardial infarction, sequelae such as heart failure and sudden death threaten the future wellbeing of those patients. Secondary prevention after myocardial infarction is related to cardiovascular risk factors and the effect of the infarct on left ventricular function. Cardiovascular magnetic resonance imaging (CMR) is necessary to determine the size of the infarct scar and can with great precision determine left ventricular volumes, left ventricular ejection fraction, and deformation (strain and torsion). The purpose of this thesis was to improve on CMR methods to facilitate image acquisition and post processing in patients with high risk of coronary artery disease (CAD). In Paper 1, a three-dimensional phase-sensitive inversion-recovery (3D PSIR) sequence was modified to measure T1 during a single breath hold. The measured T1 values were used to extrapolate a map of T1 relaxation, which avoided the time-consuming manual determination of the inversion time. The data collection consisted of phantom experiments, Monte Carlo simulations of the effect of various heart rates, and clinical investigation of 18 patients with myocardial infarction. Scar images created with the modified sequence were compared to those created with the standard sequence. The 3D PSIR sequence was able to measure T1 relaxation with a high accuracy up to 800 ms, which is in the suitable range for scar imaging. Simulated arrhythmias showed that the method was robust and able to tolerate some variation in heart rate. The modified sequence provides measurements of inversion time that can be used to facilitate standard scar imaging or to reconstruct synthetic scar images. Images of infarct scar obtained with the 3D PSIR sequence bore striking similarity to images obtained with the standard sequence. In Paper 2, 125 patients with high risk of CAD were investigated using the displacement encoding with stimulated echoes (DENSE) sequence. Image segments with infarct scar area >50% (transmurality) could be identified with a sensitivity of 95% and a specificity of 80% based on circumferential strain calculated from the DENSE measurements. The DENSE sequence was also applied in other directions, but its sensitivity and specificity to detect scar was lower than when used for circumferential strain. In Paper 3, 90 patients with high risk of CAD were examined by DENSE, tagging with harmonic phase (HARP) imaging and cine imaging with feature tracking (FT), to detect cardiac abnormalities as manifested in end-systolic circumferential strain. Circumferential strain calculated with DENSE had higher sensitivity and specificity than the competing methods to detect infarction with transmurality >50%. Global circumferential strain measured by DENSE correlated better with global parameters such as left ventricular ejection fraction, myocardial wall mass, left ventricular end-diastolic and end-systolic volume; than strain measured by FT or HARP. In Paper 4, myocardial torsion was investigated using DENSE, HARP, and FT in 48 patients with high risk of CAD. Torsion measured by each of the three methods was correlated with other global measures such as left ventricular ejection fraction, left ventricular mass, and left ventricular end-diastolic and end-systolic volumes. The torsion measurements obtained with DENSE had a stronger relationship with left ventricular ejection fraction, left ventricular mass, and volumes than those obtained with HARP or FT. DENSE was superior to the other methods for strain and torsion measurement and can be used to describe myocardial deformation quantitatively and objectively.

Disclaimer: www.yourbookbest.com does not own Magnetic Resonance Imaging of Myocardial Deformation and Scarring in Coronary Artery Disease. books pdf, neither created or scanned. We just provide the link that is already available on the internet, public domain and in Google Drive. If any way it violates the law or has any issues, then kindly mail us via contact us page to request the removal of the link.

Dilated Cardiomyopathy

Dilated Cardiomyopathy

File Size : 5,5 MB
Total View : 7674 Views
DOWNLOAD

This open access book presents a comprehensive overview of dilated cardiomyopathy, providing readers with practical guidelines for its clinical management. The

Heart Mechanics

Heart Mechanics

File Size : 80,80 MB
Total View : 9290 Views
DOWNLOAD

Based on research and clinical trials, this book details the latest research in magnetic resonance imaging (MRI) tagging technology related to heart mechanics.