The original study "Calcium-Channel Blockers and Primary Prevention of Coronary Heart Disease" was conducted from 1991 to 1995 and was designed to determine whether the calcium-channel blockers reduced the incidence of myocardial infarction (MI) in patients with hypertension. Secondary aims included the evaluation of the relative efficacy and safety of other major drug classes, including ACE inhibitors, beta-blockers, and alpha blockers. The study originated to answer questions concerning the 1988 recommendations from the Joint National Committee on Detection, Evaluation, and Treatment of High Blood Pressure (JNC V). The 1988 recommendations from the Joint National Committee revolutionized the step-care approach to the treatment of hypertension: the calcium- channel blockers, a then new class of agents, were included as first-line agents. That they lowered blood pressure was clear. But no randomized trial had yet evaluated their safety and efficacy in terms of the clinical endpoints of stroke and coronary heart disease. Because the results of previous randomized trials suggested that the treatment of hypertension did not reduce the incidence of coronary heart disease, the study was designed to answer that question.