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Cardiovascular magnetic resonance assessment of the aortic valve stenosis: an in vivo and ex vivo study.

Buchner S, Debl K, Schmid FX, Luchner A, Djavidani B - BMC Med Imaging (2015)

Bottom Line: The mean AVA determined in vivo by CMR was 0.75 ± 0.09 cm(2) and ex vivo by CMR was 0.65 ± 0.09 cm(2) and was closely correlated (r = 0.91, p < 0.001).The mean absolute difference between AVA derived by CMR ex vivo and in vivo was -0.10 ± 0.04 cm(2).The mean AVA using TTE was 0.69 ± 0.07 with a significant correlation between CMR ex vivo (r = 0.85, p < 0.007) and CMR in vivo (r = 0.86, p < 0.008).

View Article: PubMed Central - PubMed

Affiliation: Klinik und Poliklinik für Innere Medizin II, Universitätsklinikum Regensburg, Franz-Josef-Strauss-Allee 11, 93042, Regensburg, Germany. stefan.buchner@ukr.de.

ABSTRACT

Background: Aortic valve area (AVA) estimation in patients with aortic stenosis may be obtained using several methods. This study was undertaken to verify the cardiovascular magnetic resonance (CMR) planimetry of aortic stenosis by comparing the findings with invasive catheterization, transthoracic (TTE) as well as tranesophageal echocardiography (TEE) and anatomic CMR examination of autopsy specimens.

Methods: Our study was performed in eight patients with aortic valve stenosis. Aortic stenosis was determined by TTE and TEE as well as catheterization and CMR. Especially, after aortic valve replacement, the explanted aortic valves were examined again with CMR ex vivo model.

Results: The mean AVA determined in vivo by CMR was 0.75 ± 0.09 cm(2) and ex vivo by CMR was 0.65 ± 0.09 cm(2) and was closely correlated (r = 0.91, p < 0.001). The mean absolute difference between AVA derived by CMR ex vivo and in vivo was -0.10 ± 0.04 cm(2). The mean AVA using TTE was 0.69 ± 0.07 with a significant correlation between CMR ex vivo (r = 0.85, p < 0.007) and CMR in vivo (r = 0.86, p < 0.008). CMR ex vivo and in vivo had no significant correlation with AVA using Gorlin formula by invasive catheterization or using planimetry by TEE.

Conclusion: In this small study using an ex vivo aortic valve stenosis model, the aortic valve area can be reliably planimetered by CMR in vivo and ex vivo with a well correlation between geometric AVA by CMR and the effective AVA calculated by TTE.

No MeSH data available.


Related in: MedlinePlus

To avoid assessing the aortic valve area beyond or above the leaflet tips, the imaging plane was moved shift wise in one mm steps in an orthograd direction. Planimetry was chosen on the slice where the smallest orifice was surrounded totally by the edge of the valve
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Fig2: To avoid assessing the aortic valve area beyond or above the leaflet tips, the imaging plane was moved shift wise in one mm steps in an orthograd direction. Planimetry was chosen on the slice where the smallest orifice was surrounded totally by the edge of the valve

Mentions: All specimens were examined on a 1.5 T scanner (Magnetom Sonata, Siemens Medical Solutions, Erlangen, Germany). The CMR imaging protocol included a 3D-CISS protocol (TR/TE/flip angle 17/8.08 ms/70° ms, band width 130 Hz/pixel, effective slice thickness 1 mm pixel size 0.6 × 0.45 mm). The aortic valve was placed on a rack into a water container. Then the container with the aortic valve was placed in the gantry. Slices in the orthogonal planes (transverse, coronal and sagittal) were obtained (Fig. 1). Serial angulated-axis views from the base to tip of the valve were acquired with 3D sequence (Fig. 2). Planimetry of the smallest orifice was performed by two independent observers, who were unaware of the echocardiographic, catheterization and in vivo results. We placed our traces at the edge of the bright pixels. Three measurements were performed and average for calculating the AVA. Intraobserver and interobserver variabilities were 1 % and 4 % for ex vivo CMR, respectively.Fig. 1


Cardiovascular magnetic resonance assessment of the aortic valve stenosis: an in vivo and ex vivo study.

Buchner S, Debl K, Schmid FX, Luchner A, Djavidani B - BMC Med Imaging (2015)

To avoid assessing the aortic valve area beyond or above the leaflet tips, the imaging plane was moved shift wise in one mm steps in an orthograd direction. Planimetry was chosen on the slice where the smallest orifice was surrounded totally by the edge of the valve
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4548454&req=5

Fig2: To avoid assessing the aortic valve area beyond or above the leaflet tips, the imaging plane was moved shift wise in one mm steps in an orthograd direction. Planimetry was chosen on the slice where the smallest orifice was surrounded totally by the edge of the valve
Mentions: All specimens were examined on a 1.5 T scanner (Magnetom Sonata, Siemens Medical Solutions, Erlangen, Germany). The CMR imaging protocol included a 3D-CISS protocol (TR/TE/flip angle 17/8.08 ms/70° ms, band width 130 Hz/pixel, effective slice thickness 1 mm pixel size 0.6 × 0.45 mm). The aortic valve was placed on a rack into a water container. Then the container with the aortic valve was placed in the gantry. Slices in the orthogonal planes (transverse, coronal and sagittal) were obtained (Fig. 1). Serial angulated-axis views from the base to tip of the valve were acquired with 3D sequence (Fig. 2). Planimetry of the smallest orifice was performed by two independent observers, who were unaware of the echocardiographic, catheterization and in vivo results. We placed our traces at the edge of the bright pixels. Three measurements were performed and average for calculating the AVA. Intraobserver and interobserver variabilities were 1 % and 4 % for ex vivo CMR, respectively.Fig. 1

Bottom Line: The mean AVA determined in vivo by CMR was 0.75 ± 0.09 cm(2) and ex vivo by CMR was 0.65 ± 0.09 cm(2) and was closely correlated (r = 0.91, p < 0.001).The mean absolute difference between AVA derived by CMR ex vivo and in vivo was -0.10 ± 0.04 cm(2).The mean AVA using TTE was 0.69 ± 0.07 with a significant correlation between CMR ex vivo (r = 0.85, p < 0.007) and CMR in vivo (r = 0.86, p < 0.008).

View Article: PubMed Central - PubMed

Affiliation: Klinik und Poliklinik für Innere Medizin II, Universitätsklinikum Regensburg, Franz-Josef-Strauss-Allee 11, 93042, Regensburg, Germany. stefan.buchner@ukr.de.

ABSTRACT

Background: Aortic valve area (AVA) estimation in patients with aortic stenosis may be obtained using several methods. This study was undertaken to verify the cardiovascular magnetic resonance (CMR) planimetry of aortic stenosis by comparing the findings with invasive catheterization, transthoracic (TTE) as well as tranesophageal echocardiography (TEE) and anatomic CMR examination of autopsy specimens.

Methods: Our study was performed in eight patients with aortic valve stenosis. Aortic stenosis was determined by TTE and TEE as well as catheterization and CMR. Especially, after aortic valve replacement, the explanted aortic valves were examined again with CMR ex vivo model.

Results: The mean AVA determined in vivo by CMR was 0.75 ± 0.09 cm(2) and ex vivo by CMR was 0.65 ± 0.09 cm(2) and was closely correlated (r = 0.91, p < 0.001). The mean absolute difference between AVA derived by CMR ex vivo and in vivo was -0.10 ± 0.04 cm(2). The mean AVA using TTE was 0.69 ± 0.07 with a significant correlation between CMR ex vivo (r = 0.85, p < 0.007) and CMR in vivo (r = 0.86, p < 0.008). CMR ex vivo and in vivo had no significant correlation with AVA using Gorlin formula by invasive catheterization or using planimetry by TEE.

Conclusion: In this small study using an ex vivo aortic valve stenosis model, the aortic valve area can be reliably planimetered by CMR in vivo and ex vivo with a well correlation between geometric AVA by CMR and the effective AVA calculated by TTE.

No MeSH data available.


Related in: MedlinePlus