In the heart, a ventricle is a chamber which collects blood from an atrium (another heart chamber) and pumps it out of the heart.

In a four-chambered heart, such as that in humans, there are two ventricles: the right ventricle pumps blood into the pulmonary circulation for the lungs, and the left ventricle pumps blood into the systemic circulation for the rest of the body. (See Double circulatory system for details.)

Ventricles have thicker walls than the atria, and thus can withstand the higher blood pressure.

See also:

• Cardiology
• Ventricular action potential
• Arrhythmogenic right ventricular dysplasia
• Premature ventricular contraction
• Ejection fraction
• Ventricular tachycardia
• Ventricular fibrillation
• Ventricular septal defect
• Ventricular assist device (VAD), a temporary 'blood-pumping' device for patient use while the heart is 'healing' or 'being fixed'
• Pulmonary hypertension, which often leads to hypertrophy of the right ventricle (Ventricular hypertrophy)