Impact of supervised exercise on skeletal muscle blood flow and vascular function measured with MRI in patients with peripheral artery disease.

Supervised exercise is a common therapeutic intervention for patients with peripheral artery disease (PAD), however, the mechanism underlying the improvement in claudication symptomatology is not completely understood. The hypothesis that exercise improves microvascular blood flow is herein tested via temporally resolved magnetic resonance imaging (MRI) measurement of blood flow and oxygenation dynamics during reactive hyperemia in the leg with the lower ankle-brachial index. One hundred and forty-eight subjects with PAD were prospectively assigned to standard medical care or 3 mo of supervised exercise therapy.

Multiparametric assessment of vascular function in peripheral artery disease: dynamic measurement of skeletal muscle perfusion, blood-oxygen-level dependent signal, and venous oxygen saturation.

Background: Endothelial dysfunction present in patients with peripheral artery disease may be better understood by measuring the temporal dynamics of blood flow and oxygen saturation during reactive hyperemia than by conventional static measurements.

Methods And Results: Perfusion, Intravascular Venous Oxygen saturation, and T2* (PIVOT), a recently developed MRI technique, was used to measure the response to an ischemia-reperfusion paradigm in 96 patients with peripheral artery disease of varying severity and 10 healthy controls. Perfusion, venous oxygen saturation SvO2, and T2* were each quantified in the calf at 2-s temporal resolution, yielding a dynamic time course for each variable.

Commissions and omissions are dissociable aspects of everyday action impairment in schizophrenia.

Prior research using performance-based assessment of functional impairment has informed a novel neuropsychological model of everyday action impairment in dementia in which omission errors (i.e., failure to complete task steps) dissociate from commission errors (i.