Skip to Main content Skip to Navigation
Theses

Apport de l'imagerie fonctionnelle à l'étude des couplages entre la perfusion, le métabolisme glucidique et la fonction contractile dans l'ischémie myocardique

Abstract : The study of the myocardial viability is a critical factor in guiding medical decisions regarding coronary artery disease (CAD) patients. The knowledge of the relationship between perfusion, metabolism and myocardial contractile function is essential in distinguishing the pathophysiological consequences of the ischemic injury and so, to determine myocardial viability. We evaluated in CAD patients (n=43), the relationship between perfusion (by positron emission tomography –PET- and 18FDG), glucose metabolism (by PET and H215O) and intramyocardial contractile function (by tagged magnetic resonance imaging –MRI-).
Firstly, we studied the relationship between regional values of perfusion and glucose metabolism. Perfusion was evaluated at rest and after Dipyridamole stimulation for coronary reserve estimations. Glucose metabolism measurements were carried out under hyperinsulinemic euglycemic clamp for standardization of metabolic conditions. For each patient, the distribution of regional perfusion and glucose metabolism was analyzed and it showed large inter-individual differences. Such differences allowed to determining that myocardial hibernation (classically defined as viable) associated to reversible stress defects is specific of patients with preserved perfusion and glucose uptake.
Next, we added the quantitative evaluation of the intramyocardial contractile function to the coupling between regional perfusion and glucose metabolism. Contractile function was assessed at rest and after Dobutamine for evaluating inotropic reserve. Our results showed that resting contractile function relates to perfusion and glucose metabolism, but the presence of inotropic reserve does not.
Finally, we included in the Appendix a work aiming to provide a useful clinical tool for perfusion evaluations with MRI. In this pilot study in humans (13 patients, 5 normal volunteers) we showed the value of FAMIS applied to first-pass MR imaging series in detecting perfusion defects.
Complete list of metadatas

Cited literature [143 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-00004470
Contributor : Alejandro N. Mazzadi <>
Submitted on : Wednesday, February 4, 2004 - 11:51:23 AM
Last modification on : Friday, November 6, 2020 - 4:13:23 AM
Long-term archiving on: : Wednesday, September 12, 2012 - 1:05:26 PM

Identifiers

  • HAL Id : tel-00004470, version 1

Citation

Alejandro N. Mazzadi. Apport de l'imagerie fonctionnelle à l'étude des couplages entre la perfusion, le métabolisme glucidique et la fonction contractile dans l'ischémie myocardique. Physiologie [q-bio.TO]. Université Claude Bernard - Lyon I, 2003. Français. ⟨tel-00004470⟩

Share

Metrics

Record views

794

Files downloads

639