Blood Flow Redistribution During Exercise Contributes to Exercise Tolerance in Patients With Chronic Heart Failure

Background It is widely known that blood flow redistribution is impaired in patients with chronic heart failure (CHF). However, the relationship between exercise tolerance and the degree of blood flow redistribution is not fully understood. Whole-body thallium-201 chloride (201Tl) scintigraphy can estimate blood flow distribution. This study will evaluate the relationship between exercise tolerance and blood flow redistribution using whole-body scintigraphy in patients with CHF. Methods and Results Exercise stress whole-body thallium scintigraphy was performed in 19 patients with CHF (mean ejection fraction: 33.0%; peak oxygen uptake: 15.5 ml · min-1 · kg-1). Blood flow redistribution was quantified by comparing the regional thallium count (count/pixel) in the thigh and arm. We then assessed the relationship between these parameters and parameters obtained from cardiopulmonary exercise testing. 201Thallium-chloride uptake in the thigh increased during exercise compared to rest (p