A cardiac stimulant is a drug which acts as a stimulant of the heart – e.g., via positive chronotropic action (increased heart rate) and/or inotropic action (increased myocardial contractility).
They increase cardiac output (the amount of blood pumped by the heart over time).
Exercise is also a cardiac stimulant by increasing levels of the sympathomimetic catecholamines epinephrine and norepinephrine.
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