[en] We compared two different magnetic resonance (MR) sequences [steady-state free precession (SSFP) and gradient echo fast low-angle shot (FLASH)] for the assessment of aortic valve areas in aortic stenosis using transesophageal echocardiography (TEE) as the standard of reference. Thirty-two patients with known aortic stenosis underwent MR (1.5 T) using a cine SSFP sequence and a cine FLASH sequence. Planimetry was performed in cross-sectional images and compared to the results of the TEE. In seven patients the grade of stenosis was additionally assessed by invasive cardiac catheterization (ICC). The mean aortic valve area measured by TEE was 0.97±0.19 mm², 1.00±0.25 mm² for SSFP and 1.25±0.23 mm² based on FLASH images. The mean difference between the valve areas assessed based on SSFP and TEE images was 0.15±0.13 cm² (FLASH vs TEE: 0.29±0.17 cm²). Bland-Altman analysis demonstrated that measurements using FLASH images overestimated the aortic valve area compared to TEE. Comparing ICC with MRI and TEE, only a weak to moderate correlation was found (ICC vs TEE: R=0.52, p=0.22; ICC vs SSFP: R=0.20, p=0.65; ICC vs FLASH: R=0.16, p=0.70). Measurements of the aortic valve area based on SSFP images correlate better with TEE compared to FLASH images. (orig.)

[en] The purpose of the study was to estimate T₁ values of blood and myocardium after a single injection of Vasovist trademark and to assess Vasovist trademark for magnetic resonance coronary angiography (MRCA). For all exams 0.05 mmol/kg of Vasovist trademark was injected. T₁ values of blood and myocardium were estimated over 30 min after injection. Twelve volunteers were examined on a 1.5-T Siemens system using a SSFP sequence with incrementally increasing inversion times for T₁-estimation and a breath-hold 3D IR-FLASH sequence for MRCA. Eleven examinations were performed on 1.5-T Philips system using the Look-Locker approach for T₁ estimation and a whole-heart inversion-prepared, 3D SSFP sequence for MRCA. SNR, CNR and image quality were assessed. T₁ values of blood (5 min: 230 ms vs. 30 min: 275 ms) and myocardium (5 min: 99 ms vs. 30 min: 130 ms) increased over time. Whereas the blood SNR (1 min: 23.6 vs. 30 min: 21.2) showed no significant differences, the blood-to-myocardium CNR (1 min: 18.1 vs. 30 min: 13.8) and the image quality (1 min: 2.9 vs. 30 min: 3.8) degraded over time. Due to long plasma half-time the T1-shortening effect of Vasovist trademark remains effective over 30 min, which allows for multiple breath-hold or high-resolution MRCA. (orig.)