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heartstimulatory

Heartstimulatory is a term used to describe substances or physiological processes that increase the activity of the heart. In practice, it usually refers to agents or conditions that raise heart rate (positive chronotropy) and/or the force of myocardial contraction (positive inotropy). Heartstimulatory effects can be natural, such as the release of adrenaline during stress, or pharmacological, through drugs designed to activate cardiac receptors or signaling pathways. The term is not a formal clinical category, but it is commonly used to describe positive chronotropic and inotropic actions.

Most clinically significant heartstimulatory effects arise from activation of beta-1 adrenergic receptors in the heart, which

Common heartstimulatory drugs include epinephrine, norepinephrine, dopamine, dobutamine, and isoproterenol, used in settings such as cardiac

Nonpharmacologic heartstimulation occurs with exercise, thyroid hormone effects, and autonomic regulation. While beneficial for performance and

Related topics include positive inotropes, chronotropic agents, inotropy, and pacemakers.

increases
intracellular
cAMP
and
calcium
availability,
speeding
both
rate
and
contractility.
Other
mechanisms
include
phosphodiesterase
inhibition,
which
raises
cAMP
(for
example
milrinone),
or
calcium
sensitization.
Some
agents
also
modify
heart
rhythm
or
conduction,
influencing
how
quickly
the
heart
can
respond
to
increased
demand.
arrest,
shock,
or
acute
heart
failure
under
close
monitoring.
Milrinone
is
used
in
heart
failure
with
reduced
ejection
fraction
to
improve
output.
The
choice
of
agent
depends
on
desired
effect,
blood
pressure,
and
risk
of
tachyarrhythmia
or
myocardial
ischemia.
adaptation,
excessive
stimulation
can
increase
myocardial
oxygen
demand
and
precipitate
arrhythmias
or
ischemia
in
vulnerable
individuals.