- Poster presentation
- Open Access
Exercise induced changes in T1, T2 relaxation times and blood flow in the lower extremities in healthy subjects
© Varghese et al; licensee BioMed Central Ltd. 2013
- Published: 30 January 2013
- Peripheral Arterial Disease
- Superficial Femoral Artery
- Calf Muscle
- Magnetic Resonance Imaging System
- Post Exercise
Current approaches to evaluate peripheral arterial disease (PAD) overwhelmingly rely on quantification of stenosis severity or flow across stenosis at rest. Although exercise-induced functional alterations in metabolism have been proposed, there is a need to integrate approaches that provide additional risk measures in PAD that can be translated into clinical practice . Recently, quantitative T1/T2 mapping have allowed their usage as risk indicators in the coronary circulation.
To develop analogous risk-markers in PAD, we initially designed experiments to assess the feasibility of an approach combining quantitative magnetic resonance imaging (MRI) relaxometry of skeletal muscle with treadmill exercise testing. We investigated exercise-induced shifts in quantitative skeletal muscle relaxometry measures [2, 3] in lower extremity muscle beds in conjunction with quantitative arterial flow to the inflow vessel as an index of conduit vessel flow-reserve in healthy volunteers [4, 5].
We have demonstrated the feasibility of assessing exercise induced changes in MRI relaxometric measures and compared these with changes in exercise induced flow in the lower extremities. The changes in T1 and T2 were generally coupled to changes in flow except in older age group some of whom had higher baseline T2 and abnormal post-exercise T2 recovery. We hypothesize that patients at risk for PAD related complications may demonstrate abnormal kinetics of T1 and T2 recovery with exercise due to ischemia induced loss of microvascular integrity and tissue edema.
Funding: 10CRP3610010 - American Heart Association
- Kramer C: . Top Magn Reson Imaging. 2007, 18 (5): 357-369. 10.1097/rmr.0b013e31815d064c.PubMed CentralView ArticlePubMedGoogle Scholar
- Yoshioka H, Anno I, Kuramoto K, et al: . Magn. Reson. Imaging. 1995, 13 (5): 651-659. 10.1016/0730-725X(95)00018-C.View ArticlePubMedGoogle Scholar
- Fleckenstein J, Canby R, Parkey R, et al: . AJR. 1988, 151: 231-237.View ArticlePubMedGoogle Scholar
- Nagaraj H, Pednekar A, Corros C, et al: . J. Magn. Reson. Imaging. 2008, 27: 1096-1102. 10.1002/jmri.21336.View ArticlePubMedGoogle Scholar
- Klein W, Bartels L, Bax L, et al: . J. Vasc. Surg. 2003, 38 (5): 1060-1066. 10.1016/S0741-5214(03)00706-7.View ArticlePubMedGoogle Scholar
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.