| 1. |
- Fyrdahl, A., et al.
(författare)
-
Sector-wise golden-angle phase contrast with high temporal resolution for evaluation of left ventricular diastolic dysfunction
- 2020
-
Ingår i: Magnetic Resonance in Medicine. - : Wiley. - 0740-3194 .- 1522-2594. ; 83:4, s. 1310-1321
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose To develop a high temporal resolution phase‐contrast pulse sequence for evaluation of diastolic filling patterns, and to evaluate it in comparison to transthoracic echocardiography. Methods A phase‐contrast velocity‐encoded gradient‐echo pulse sequence was implemented with a sector‐wise golden‐angle radial ordering. Acquisitions were optimized for myocardial tissue (TE/TR: 4.4/6.8 ms, flip angle: 8º, velocity encoding: 30 cm/s) and transmitral flow (TE/TR: 4.0/6.6 ms, flip angle: 20º, velocity encoding: 150 cm/s). Shared velocity encoding was combined with a sliding‐window reconstruction that enabled up to 250 frames per cardiac cycle. Transmitral and myocardial velocities were measured in 35 patients. Echocardiographic velocities were obtained with pulsed‐wave Doppler using standard methods. Results Myocardial velocity showed a low difference and good correlation between MRI and Doppler (mean ± 95% limits of agreement 0.9 ± 3.7 cm/s, R2 = 0.63). Transmitral velocity was underestimated by MRI (P < .05) with a difference of −11 ± 28 cm/s (R2 = 0.45). The early‐to‐late ratio correlated well (R2 = 0.66) with a minimal difference (0.03 ± 0.6). Analysis of interobserver and intra‐observer variability showed excellent agreement for all measurements. Conclusions The proposed method enables the acquisition of phase‐contrast images during a single breath‐hold with a sufficiently high temporal resolution to match transthoracic echocardiography, which opens the possibility for many clinically relevant variables to be assessed by MRI.
|
|
| 2. |
- Lundin, M., et al.
(författare)
-
Diffusely Increased Myocardial Extracellular Volume with or without Focal Late Gadolinium Enhancement: Prevalence and Associations with Left Ventricular Size and Function
- 2022
-
Ingår i: Journal of Thoracic Imaging. - 0883-5993 .- 1536-0237. ; 37:1, s. 17-25
-
Tidskriftsartikel (refereegranskat)abstract
- Purpose: Myocardial extracellular volume fraction (ECV) using cardiovascular magnetic resonance (CMR) can identify diffuse lesions not detected by late gadolinium enhancement (LGE). We aimed to determine the prevalence of increased ECV and its relation to other CMR findings. Materials and Methods: Consecutive patients (n=609, age median [interquartile range] 53 [39 to 66] y, 62% male) underwent CMR at 1.5 T. Focal lesions on LGE images were noted. ECV in regions without focal LGE findings defined diffuse changes. Pronounced increases in left ventricular (LV) end-diastolic volume index and LV mass index, and pronounced decreases in LV ejection fraction were defined as >3 SD from the sex-specific mean in healthy volunteers. Results: Of 609 patients without amyloidosis or hypertrophic cardiomyopathy, 8% had diffusely increased ECV and 5% of all patients had diffusely increased ECV without any focal LGE findings. Multivariate analysis showed that a pronounced increase in the LV end-diastolic volume index was associated with increased ECV (P=0.001), but not LGE (P=0.52). A pronounced decrease in LV ejection fraction was associated with the presence of LGE (P<0.001), but not with increased ECV (P=0.41). Conclusions: Eight percent of patients in this clinical cohort with known or suspected heart disease had diffusely increased ECV and 60% of these lacked focal LGE findings. LV size is independently associated with increased ECV, whereas systolic dysfunction is independently associated with LGE. This image-based clinical study demonstrates that ECV-CMR provides additional information negligibly related to the results of LGE imaging, and thereby increases the diagnostic yield of CMR. © 2020 Lippincott Williams and Wilkins. All rights reserved.
|
|
| 3. |
|
|
| 4. |
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
|
|
| 8. |
- Nickander, J, et al.
(författare)
-
Females have higher myocardial perfusion, blood volume and extracellular volume compared to males - an adenosine stress cardiovascular magnetic resonance study
- 2020
-
Ingår i: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 10:1, s. 10380-
-
Tidskriftsartikel (refereegranskat)abstract
- Knowledge on sex differences in myocardial perfusion, blood volume (MBV), and extracellular volume (ECV) in healthy individuals is scarce and conflicting. Therefore, this was investigated quantitatively by cardiovascular magnetic resonance (CMR). Healthy volunteers (n = 41, 51% female) underwent CMR at 1.5 T. Quantitative MBV [%] and perfusion [ml/min/g] maps were acquired during adenosine stress and at rest following an intravenous contrast bolus (0.05 mmol/kg, gadobutrol). Native T1 maps were acquired before and during adenosine stress, and after contrast (0.2 mmol/kg) at rest and during adenosine stress, rendering rest and stress ECV maps. Compared to males, females had higher perfusion, ECV, and MBV at stress, and perfusion and ECV at rest (p < 0.01 for all). Multivariate linear regression revealed that sex and MBV were associated with perfusion (sex beta −0.31, p = 0.03; MBV beta −0.37, p = 0.01, model R2 = 0.29, p < 0.01) while sex and hematocrit were associated with ECV (sex beta −0.33, p = 0.03; hematocrit beta −0.48, p < 0.01, model R2 = 0.54, p < 0.001). Myocardial perfusion, MBV, and ECV are higher in female healthy volunteers compared to males. Sex is an independent contributor to perfusion and ECV, beyond other physiological factors that differ between the sexes. These findings provide mechanistic insight into sex differences in myocardial physiology.
|
|
| 9. |
- Ramos, J. G., et al.
(författare)
-
Comprehensive Cardiovascular Magnetic Resonance Diastolic Dysfunction Grading Shows Very Good Agreement Compared With Echocardiography
- 2020
-
Ingår i: Jacc-Cardiovascular Imaging. - : Elsevier BV. - 1936-878X .- 1876-7591. ; 13:12, s. 2530-2542
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES The aims of this study were to develop a comprehensive cardiovascular magnetic resonance (CMR) approach to diastolic dysfunction (DD) grading and to evaluate the accuracy of CMR in the diagnosis of DD compared with echocardiography. BACKGROUND Left ventricular DD is routinely assessed using echocardiography. METHODS Consecutive clinically referred patients (n = 46; median age 59 years; interquartile range: 46 to 68 years; 33% women) underwent both conventional echocardiography and CMR. CMR diastolic transmitral velocities (E and A) and myocardial tissue velocity (e0) were measured during breath-hold using a validated high-temporal resolution radial sector-wise golden-angle velocity-encoded sequence. CMR pulmonary artery pressure was estimated from 4-dimensional flow analysis of blood flow vortex duration in the pulmonary artery. CMR left atrial volume was measured using the biplane long-axis area-length method. Both CMR and echocardiographic data were used to perform blinded grading of DD according to the 2016 joint American and European recommendations. RESULTS Grading of DD by CMR agreed with that by echocardiography in 43 of 46 cases (93%), of which 9% were normal, 2% indeterminate, 63% grade 1 DD, 4% grade 2 DD, and 15% grade 3 DD. There was a very good categorical agreement, with a weighted Cohen kappa coefficient of 0.857 (95% confidence interval: 0.73 to 1.00; p < 0.001). CONCLUSIONS A comprehensive CMR protocol for grading DD encompassing diastolic blood and myocardial velocities, estimated pulmonary artery pressure, and left atrial volume showed very good agreement with echocardiography. (C) 2020 by the American College of Cardiology Foundation.
|
|
