Cardiac stimulant

Cardiac stimulants are a class of pharmacological agents that increase the output force of the heart and its rate of contractions by acting on the electrical conductivity of the heart, the cells of the heart or the overall health of the heart.

Mechanism of Action

Cardiac stimulants work by increasing the strength of the heart's contractions and the heart rate. This is achieved by enhancing the influx of calcium ions into the cardiomyocytes during the plateau phase of the action potential. The increased calcium influx results in more forceful contractions and a faster heart rate.

Types of Cardiac Stimulants

There are several types of cardiac stimulants, including:

• Digitalis: This is a type of cardiac stimulant derived from the foxglove plant. It works by inhibiting the sodium-potassium ATPase pump, which increases intracellular calcium levels and strengthens the force of heart contractions.

• Dopamine: This is a neurotransmitter that, when used as a cardiac stimulant, acts on beta-1 adrenergic receptors in the heart to increase heart rate and contractility.

• Dobutamine: This is a synthetic drug that acts on beta-1 adrenergic receptors in the heart to increase heart rate and contractility.

Uses

Cardiac stimulants are used in the treatment of various heart conditions, including heart failure, cardiogenic shock, and certain types of arrhythmia. They are also used during cardiac stress testing to increase the heart rate and force of contractions.

Side Effects

Like all medications, cardiac stimulants can have side effects. These may include arrhythmia, hypertension, angina, and in severe cases, cardiac arrest.

See Also

• Cardiology
• Pharmacology
• Heart failure
• Arrhythmia