Translations:Calcium channel blocker/30/en
Since blood pressure is in intimate feedback with cardiac output and peripheral resistance, with relatively low blood pressure, the afterload on the heart decreases; this decreases how hard the heart must work to eject blood into the aorta, so the amount of oxygen required by the heart decreases accordingly. This can help ameliorate symptoms of ischaemic heart disease such as angina pectoris.

Reducing the force of contraction of the myocardium is known as the negative inotropic effect of calcium channel blockers.