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Muscle Metaboreflex Control Of Coronary Blood Flow And Ventricular Contractility During Dynamic Exercise In Normal And Heart Failure Conditions, Matthew Coutsos

Wayne State University Dissertations

Muscle metaboreflex activation during dynamic exercise induces a substantial increase in cardiac work and oxygen demand via a significant increase in heart rate, ventricular contractility and afterload. This increase in cardiac work should cause coronary metabolic vasodilation. However, little if any coronary vasodilation is observed due to concomitant sympathetically induced coronary vasoconstriction. In heart failure, cardiac output does not increase with MMA presumably due to impaired left ventricular contractility, and large decreases in coronary vascular conductance are observed. The purpose of this dissertation is to determine whether the muscle metaboreflex-induced restraint of coronary vasodilation functionally limits coronary blood flow and …