Journal of cardiovascular magnetic resonance : official journal of the Society for Cardiovascular Magnetic Resonance
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J Cardiovasc Magn Reson · Jan 2005
Case ReportsFunctional and metabolic recovery of the right ventricle during Bosentan therapy in idiopathic pulmonary arterial hypertension.
An impaired high-energy phosphate metabolism might play a critical role in the pathogenesis of right ventricular (RV) failure due to chronic pulmonary arterial hypertension (PAH). 31P-NMR spectroscopy is well established for measurements of high-energy phosphate metabolites in various left ventricular heart diseases, however, mainly for technical and sensitivity reasons, its successful transfer for measurements in the RV is currently missing. In the present study, the usefulness of this non-invasive approach is not only shown in RV failure due to PAH but also tested during subsequent therapy.
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J Cardiovasc Magn Reson · Jan 2004
Early regression of left ventricular hypertrophy after aortic valve replacement by the Ross procedure detected by cine MRI.
The primary objective of our study was to assess the time course of left ventricular remodeling after the Ross procedure with the use of cine magnetic resonance imaging (MRI). ⋯ Cine MRI allows accurate assessment of left ventricular structure and geometry before and after aortic valve replacement with pulmonary autograft and is very sensitive in detecting relatively small changes of left ventricular myocardial mass and volumes early after hemodynamic relief as well as during serial assessment.
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J Cardiovasc Magn Reson · Jan 2001
Prosthetic heart valves and annuloplasty rings: assessment of magnetic field interactions, heating, and artifacts at 1.5 Tesla.
The purpose of this study was to determine the magnetic resonance (MR) safety aspects and artifacts for three different heart valve prostheses and two different annuloplasty rings that have not been evaluated previously in association with the 1.5-T MR environment. Ex vivo testing was performed using previously described techniques for the evaluation of magnetic field interactions (deflection angle and torque), heating (gel-filled phantom and fluoroptic thermometry; 15 min of MR imaging at a whole body-averaged specific absorption rate of 1.2 W/kg), and artifacts (using T1-weighted, spin echo, and gradient echo pulse sequences). One heart valve prosthesis and one annuloplasty ring showed no magnetic field interactions. ⋯ Artifacts varied depending on the amount and type of metal used to make the implants. For the three heart valve prostheses and two annuloplasty rings, the lack of substantial magnetic field interactions and relatively minor hearing indicated that MR procedures may be conducted safetly in patients with these implants using MR systems operating with static magneticfields of 1.5 T or less. Notably, these findings essentially apply to 54 different heart valve prostheses and 37 different annuloplasty rings (i.e., based on the various models and sizes available for these implants).