Keywords:
MR, Cardiac, MR-Diffusion/Perfusion, Computer Applications-Detection, diagnosis, Contrast agent-intravenous, Diagnostic procedure, Inflammation, Hyperplasia / Hypertrophy, Haematologic diseases
Authors:
C. Cholet1, J. Mayer1, F. Legou1, F. Ridouani2, T. Damy2, A. Luciani1, H. Kobeiter1, A. Rahmouni1, J. F. Deux1; 1Créteil/FR, 2Paris/FR
Conclusion
Myocardial SI measured on SSFP sequences exhibited significant differences between control patients,
patients with SA and patients with CA.
Before injection,
myocardial SI of patients with SA was significantly higher than control subjects and patients with CA:
- The signal of SSFP images depends on the T2/T1 tissue relaxation time ratio) and we think that this difference was probably due to a lengthening of myocardial T2,
and not a shortening of myocardial T1.
- To the best of our knowledge this data has never been reported and the reason of this difference remains unclear: reaction of myocardial tissue towards abnormal circulating proteins present within microvessels of the heart ?
- The difference of myocardial SI noticed between patients with SA and patients with CA was also difficult to explain: the deposit of amyloid proteins within myocardium in patients with CA induce probably new modifications of myocardial signal.
After injection,
we noticed that both patients with SA and patients with CA exhibited a higher myocardial SI in comparison to control subjects:
- If the higher myocardial signal of patients with CA in comparison with control subjects was not surprising,
the high signal encountered in patients with SA (higher than normal subjects) was unexpected.
- To the best of our knowledge,
such data has never been reported.
- At this stage,
only hypothesis may be propose to explain this result: early deposition of amyloid proteins before LGE abnormalities ? T2 effet ?
- Despite the lack of difference of SI between patients with SA and CA after injection,
we reported that the percentage of myocardial enhancement was significantly higher in patients with CA than patients with SA.
This measurement could be of interest to detect patients with CA using SSFP sequences
This is the first study to evaluate variations of myocardial signal in patients with and without CA using SSFP sequences.
As suspected,
we reported significant variations of myocardial signal between patients with CA and control subjects after gadolinium injection using SSFP sequences.
More surprisingly,
we noticed also significant differences of signal between patients with SA and patients with CA and control subjects before and after gadolinium administration whose reasons remain unclear.
These modifications of signal may suggest that myocardial changes may exist more precociously than expected in patients with SA.
Additional studies and follow-up of these patients are required to better understand our results.