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Undersampled cine 3D tagging for rapid assessment of cardiac motion.

Stoeck CT, Manka R, Boesiger P, Kozerke S - J Cardiovasc Magn Reson (2012)

Bottom Line: Comparison of results from fully sampled in-vivo data acquired with prospectively undersampled acquisitions showed a mean difference in circumferential shortening of -0.14 ± 5.18% and 0.71 ± 6.16% for R = 3 and 4.In patients peak, circumferential shortening was significantly reduced (p < 0.002 for all patients) in regions with late gadolinium enhancement.Undersampled cine 3D tagging enables significant reduction in scan time of whole-heart tagging and facilitates quantification of shortening, rotation and torsion of the left ventricle without adding significant errors compared to previous 3D tagging approaches.

View Article: PubMed Central - PubMed

Affiliation: Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse 35, 8092, Zurich, Switzerland.

ABSTRACT

Background: CMR allows investigating cardiac contraction, rotation and torsion non-invasively by the use of tagging sequences. Three-dimensional tagging has been proposed to cover the whole-heart but data acquisition requires three consecutive breath holds and hence demands considerable patient cooperation. In this study we have implemented and studied k-t undersampled cine 3D tagging in conjunction with k-t PCA reconstruction to potentially permit for single breath-hold acquisitions.

Methods: The performance of undersampled cine 3D tagging was investigated using computer simulations and in-vivo measurements in 8 healthy subjects and 5 patients with myocardial infarction. Fully sampled data was obtained and compared to retrospectively and prospectively undersampled acquisitions. Fully sampled data was acquired in three consecutive breath holds. Prospectively undersampled data was obtained within a single breath hold. Based on harmonic phase (HARP) analysis, circumferential shortening, rotation and torsion were compared between fully sampled and undersampled data using Bland-Altman and linear regression analysis.

Results: In computer simulations, the error for circumferential shortening was 2.8 ± 2.3% and 2.7 ± 2.1% for undersampling rates of R = 3 and 4 respectively. Errors in ventricular rotation were 2.5 ± 1.9% and 3.0 ± 2.2% for R = 3 and 4. Comparison of results from fully sampled in-vivo data acquired with prospectively undersampled acquisitions showed a mean difference in circumferential shortening of -0.14 ± 5.18% and 0.71 ± 6.16% for R = 3 and 4. The mean differences in rotation were 0.44 ± 1.8° and 0.73 ± 1.67° for R = 3 and 4, respectively. In patients peak, circumferential shortening was significantly reduced (p < 0.002 for all patients) in regions with late gadolinium enhancement.

Conclusion: Undersampled cine 3D tagging enables significant reduction in scan time of whole-heart tagging and facilitates quantification of shortening, rotation and torsion of the left ventricle without adding significant errors compared to previous 3D tagging approaches.

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Related in: MedlinePlus

Comparison of peak circumferential shortening from undersampled (R = 3) and fully sampled simulated data. Myocardium was divided into three groups: infarction (I), which covers a sector of 80° (22% of myocardium), healthy tissue (H) and infarct adjacent (A) tissue “attaching” infarcted to healthy tissue over a sector of 40° (11% of myocardium). For infarcted tissue, different degrees of immobilized tissue ranging from 0% to 100% were simulated. The dashed line indicates the reference diagonal with slope 1.
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Figure 3: Comparison of peak circumferential shortening from undersampled (R = 3) and fully sampled simulated data. Myocardium was divided into three groups: infarction (I), which covers a sector of 80° (22% of myocardium), healthy tissue (H) and infarct adjacent (A) tissue “attaching” infarcted to healthy tissue over a sector of 40° (11% of myocardium). For infarcted tissue, different degrees of immobilized tissue ranging from 0% to 100% were simulated. The dashed line indicates the reference diagonal with slope 1.

Mentions: In order to study regional wall motion abnormalities, myocardial infarctions of different severity were simulated. To this end, radial shortening in the lateral sector was changed from 100% (no infarction) to 0% (completely static) in steps of 10% (Figure 3). The reduction of myocardial motion in the infarcted zone was applied transmurally along the entire long axis of the left ventricle. Reduction of radial shortening directly reduced the circumferential contraction. In order to assure a smooth transition between infarcted and healthy tissue, the infarcted tissue was continuously “attached” to the adjacent healthy tissue, by reducing the motion damping factor continuously over a sector of 40° on both ends of the infarcted region.


Undersampled cine 3D tagging for rapid assessment of cardiac motion.

Stoeck CT, Manka R, Boesiger P, Kozerke S - J Cardiovasc Magn Reson (2012)

Comparison of peak circumferential shortening from undersampled (R = 3) and fully sampled simulated data. Myocardium was divided into three groups: infarction (I), which covers a sector of 80° (22% of myocardium), healthy tissue (H) and infarct adjacent (A) tissue “attaching” infarcted to healthy tissue over a sector of 40° (11% of myocardium). For infarcted tissue, different degrees of immobilized tissue ranging from 0% to 100% were simulated. The dashed line indicates the reference diagonal with slope 1.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3472184&req=5

Figure 3: Comparison of peak circumferential shortening from undersampled (R = 3) and fully sampled simulated data. Myocardium was divided into three groups: infarction (I), which covers a sector of 80° (22% of myocardium), healthy tissue (H) and infarct adjacent (A) tissue “attaching” infarcted to healthy tissue over a sector of 40° (11% of myocardium). For infarcted tissue, different degrees of immobilized tissue ranging from 0% to 100% were simulated. The dashed line indicates the reference diagonal with slope 1.
Mentions: In order to study regional wall motion abnormalities, myocardial infarctions of different severity were simulated. To this end, radial shortening in the lateral sector was changed from 100% (no infarction) to 0% (completely static) in steps of 10% (Figure 3). The reduction of myocardial motion in the infarcted zone was applied transmurally along the entire long axis of the left ventricle. Reduction of radial shortening directly reduced the circumferential contraction. In order to assure a smooth transition between infarcted and healthy tissue, the infarcted tissue was continuously “attached” to the adjacent healthy tissue, by reducing the motion damping factor continuously over a sector of 40° on both ends of the infarcted region.

Bottom Line: Comparison of results from fully sampled in-vivo data acquired with prospectively undersampled acquisitions showed a mean difference in circumferential shortening of -0.14 ± 5.18% and 0.71 ± 6.16% for R = 3 and 4.In patients peak, circumferential shortening was significantly reduced (p < 0.002 for all patients) in regions with late gadolinium enhancement.Undersampled cine 3D tagging enables significant reduction in scan time of whole-heart tagging and facilitates quantification of shortening, rotation and torsion of the left ventricle without adding significant errors compared to previous 3D tagging approaches.

View Article: PubMed Central - PubMed

Affiliation: Institute for Biomedical Engineering, University and ETH Zurich, Gloriastrasse 35, 8092, Zurich, Switzerland.

ABSTRACT

Background: CMR allows investigating cardiac contraction, rotation and torsion non-invasively by the use of tagging sequences. Three-dimensional tagging has been proposed to cover the whole-heart but data acquisition requires three consecutive breath holds and hence demands considerable patient cooperation. In this study we have implemented and studied k-t undersampled cine 3D tagging in conjunction with k-t PCA reconstruction to potentially permit for single breath-hold acquisitions.

Methods: The performance of undersampled cine 3D tagging was investigated using computer simulations and in-vivo measurements in 8 healthy subjects and 5 patients with myocardial infarction. Fully sampled data was obtained and compared to retrospectively and prospectively undersampled acquisitions. Fully sampled data was acquired in three consecutive breath holds. Prospectively undersampled data was obtained within a single breath hold. Based on harmonic phase (HARP) analysis, circumferential shortening, rotation and torsion were compared between fully sampled and undersampled data using Bland-Altman and linear regression analysis.

Results: In computer simulations, the error for circumferential shortening was 2.8 ± 2.3% and 2.7 ± 2.1% for undersampling rates of R = 3 and 4 respectively. Errors in ventricular rotation were 2.5 ± 1.9% and 3.0 ± 2.2% for R = 3 and 4. Comparison of results from fully sampled in-vivo data acquired with prospectively undersampled acquisitions showed a mean difference in circumferential shortening of -0.14 ± 5.18% and 0.71 ± 6.16% for R = 3 and 4. The mean differences in rotation were 0.44 ± 1.8° and 0.73 ± 1.67° for R = 3 and 4, respectively. In patients peak, circumferential shortening was significantly reduced (p < 0.002 for all patients) in regions with late gadolinium enhancement.

Conclusion: Undersampled cine 3D tagging enables significant reduction in scan time of whole-heart tagging and facilitates quantification of shortening, rotation and torsion of the left ventricle without adding significant errors compared to previous 3D tagging approaches.

Show MeSH
Related in: MedlinePlus