Related Experiment Video
Updated: Jul 3, 2026

Evaluation of Coronary Flow Reserve After Myocardial Ischemia Reperfusion in Rats
Published on: June 28, 2019
Metabolic reserve of the heart: the forgotten link between contraction and coronary flow
Christos Kassiotis1, Mitra Rajabi, Heinrich Taegtmeyer
1Department of Internal Medicine, Division of Cardiology, The University of Texas Houston Medical School, Houston, TX 77030, USA.
Abstract:
Myocardial energy substrate metabolism entails a complex system of enzyme catalyzed reactions, in which the heart efficiently converts chemical to mechanical energy. The system is highly regulated and responsive to changes in workload as well as in substrate and hormone supply to the heart. Akin to the terms "contractile reserve" and "coronary flow reserve" we propose the term "metabolic reserve" to reflect the heart's capacity to respond to increases in workload. The heart's metabolic response to inotropic stimulation involves the ability to increase oxidative metabolism over a wide range, by activating the oxidation of glycogen and carbohydrate substrates. Here we review the known biochemical mechanisms responsible for those changes. Specifically, we explore the notion that disturbances in the metabolic reserve result in contractile dysfunction of the stressed heart.
Related Concept Videos
Pathophysiology of Cardiac Performance
Cardiac Output I:Effect of Heart Rate on Cardiac Output
Cardiac output (CO) refers to the total amount of blood ejected by one of the ventricles in liters per minute (L/min). In a resting adult, CO ranges from 5 to 6 L/min, adjusting according to the body's metabolic requirements.
Effect of Heart Rate on Cardiac Output
Cardiac output adapts to metabolic demands during stress, physical activity, or illness. The autonomic nervous system regulates heart rate via the sinoatrial node. The parasympathetic nervous system decreases heart rate...
Cardiac Output and Stroke Volume
In an average resting adult male, the typical cardiac output averages...
Cardiac Output II: Effect of Stroke Volume on Cardiac Output
Preload
Preload refers to the initial elongation of the cardiac myocytes before contraction and is related to the volume of blood filling the heart at the end of diastole, or end-diastolic volume. The...
Exercise and Cardiac Output
Sustained exercise increases the muscles' oxygen demand, which can be met...
Exercise and Cardiovascular Response
Light to moderate physical activity initiates a series of interconnected responses in the body. The heart rate modestly increases in anticipation of the workout, followed by widespread vasodilation as oxygen consumption by skeletal muscles increases. This results in decreased peripheral resistance, increased capillary blood flow, and accelerated...
