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H Mayr

Publications and source records attributed to H Mayr.

61 records · Page 4Linked to original sources
PubMedDate not supplied

Quantification of regurgitant lesions by MRI.

We examined 46 patients with angiographically documented regurgitant lesions (26 patients with mitral regurgitation, 20 patients with aortic regurgitation) using an 0.5 Tesla magnet. In each patient a multislice-multiphase spinecho sequence in sagittal-coronal double angulated plane was performed to assess left and right ventricular volumes, ejection fraction and regurgitant fraction. Additionally a blood flow sensitive gradient echo technique was done to visualize direction and extension of the regurgitant jet. MRI data were compared with quantitative and qualitative assessment of regurgitation by angiography and echocardiography. Using the gradient echo technique MRI could demonstrate the regurgitant jet in all patients. A linear correlation for volume parameters by MRI and angio was found with best correlation for the left ventricular stroke volume (r = 0.82, p less than 0.0001). Furthermore MRI regurgitant fraction correlated with angiographically determined regurgitant fraction in patients with aortic regurgitation (r = 0.91, p less than 0.0001) and mitral regurgitation (r = 0.67, p less than 0.001), respectively. Semiquantitative assessment of regurgitation by gradient echo technique showed an agreement with angiographic grading by Sellers in 70% of mitral and 75% of aortic regurgitation, respectively. The comparison of MRI and color Doppler sonography showed only moderate correlation of r = 0.72 (p less than 0.01).

Aortic Valve Insufficiency↗
PubMedDate not supplied

Assessment of mitral regurgitation by magnetic resonance imaging.

To evaluate the potential of magnetic resonance imaging (MRI) in detection and quantification of mitral regurgitation, 26 pts. with echocardiographically or angiographically documented mitral regurgitation were examined using a 0.5 Tesla superconducting magnet. In each patient a multislice-multiphase study in a sagittal-coronal double angulated projection (four-chamber view equivalent) was performed to assess left and right ventricular volumes, ejection fraction and regurgitant fraction. Additionally a blood flow sensitive cine-study (fast field echo: FFE) was done to visualize direction and area of regurgitant jet. MRI data were compared with quantitative and quantitative assessment of mitral regurgitation by angiography, 2D echocardiography, Doppler sonography and color flow mapping. Using the FFE mode MRI was able to detect the regurgitant jet as a typical signal loss within the left atrium in all patients. The ratio of regurgitant jet area/left atrium area as determined by MRI showed a correlation with a comparable ratio from color Doppler sonography of R = 0.87 (p less than 0.001). There was also good agreement in semiquantitative grading of mitral regurgitation between MRI and angiography (R = 0.77, p less than 0.001). The determination of left and right ventricular stroke volume allowed the calculation of the regurgitant fraction, which showed a correlation with invasively determined regurgitation fraction of R = 0.84 (p less than 0.001). These data provide additional information that MRI may be useful as a noninvasive technique to detect and quantify mitral regurgitation.

Adult↗
PubMedDate not supplied

[Menkes' disease: heterozygosity testing by quantitative real-time PCR and the dilemma of therapeutic support].

Menkes' disease is a rare X-linked multisystemic lethal disorder of copper transport metabolism. Failure of synthesis of several copper enzymes explains most of the clinical features, which were characterised by neurodegenerative symptoms and connective tissue manifestations. Most cases are still prone to rapidly progressive cerebral degeneration and early death in the first few years. Since CNS-dysfunction usually preceeds development of the pathognomonic "steely" hair, delay of clinical diagnosis and onset of therapeutic intervention precludes longlasting neurological benefit. This is particularly true for patients with large deletions or severe truncations of the responsible ATP7A gene. We report on our own experience with a patient, who was diagnosed to be affected by Menkes' syndrome at the age of one year, due to the specific hair texture and biochemical abnormalities. Molecular investigation revealed a total deletion of exon 15 of the ATP7A gene. Heterozygosity was confirmed by means of real-time PCR in the child's mother, but could be excluded in the grandmother and other female relatives at risk. Therapeutic support with subcutaneous injection of copper-histidinate normalised diminished copper and coeruloplasmin serum levels, but was unable to influence the clinical course and to prevent the fatal outcome at the age of two years. This observation is in line with the experience of the literature claiming that currently available medication will hardly be able to normalise brain copper levels. However, observations of clinical variants of Menkes' disease with quite a different outcome and, more importantly, emerging of alternative copper transport pathways might still justify this time-limited therapeutic intervention.

Adenosine Triphosphatases↗
PubMedDate not supplied

[MR-based 3D-analysis of the pathomechanics of traumatic and atraumatic shoulder instability].

AIM: Until now it is unknown to what extent malpositioning of the scapula is a relevant factor in shoulder instability that should be considered in therapy. The objective was to analyse 3D-scapular kinematics and humeral head (de-)centering in patients with atraumatic and/or traumatic shoulder instability and to investigate the correlation between the two factors. METHOD: The shoulders of 28 healthy volunteers and of 14 patients each with atraumatic or traumatic instability were examined in various arm positions - with and without muscle activity - using open MR imaging. After 3D reconstruction, analyses of scapular kinematics and glenohumeral translation were performed. RESULTS: In atraumatic unstable shoulders, the scapular position [30 degrees of abduction: scapulo-humeral rhythm: 3.5 +/- 2.6 : 1 vs. healthy 2.4 +/- 1.3 : 1; internal rotation: 59 +/- 9 degrees vs. healthy 49 +/- 3 degrees (p < 0.05)] and humeral head position was significantly decentered in both planes (p < 0.05). While the correlation between the two factors was high during passive elevation (r = 0.60-0.87), it was low during muscular activity (r = 0.25-0.62). In patients with traumatic instability no alterations of the scapula kinematics were observed. Significant humeral head decentering (p < 0.05) occurred only during abduction and external rotation. CONCLUSIONS: Patients with atraumatic instability demonstrated significant alterations of scapular kinematics and decentering of the humeral head. In traumatic instability a decentering occurred only in specific arm positions with no changes in scapula position. Because of the high correlation between the two factors, physiotherapeutic strategies for the scapula-stabilising muscles should be adapted to the direction of instability.

Adolescent↗