Painful and asymptomatic ischemia has been associated with left ventricular dysfunction, an important variable related to survival in patients with coronary artery disease. The treatment of patients with coronary artery disease with agents such as calcium channel blockers has been directed at reducing ischemia by restoring the balance between myocardial oxygen supply and demand, which ultimately serves to protect against myocardial dysfunction. Once ischemia has occurred, calcium channel blockers may protect myocardial cellular integrity and function. By reducing intracellular calcium overload during ischemia, mitochondrial function is preserved and adenosine triphosphate stores are maintained. Numerous in vitro and isolated heart preparations have shown that ischemia in the presence of calcium blockade is associated with less cellular dysfunction than in the situation of ischemia in the absence of calcium channel blockade.