Hypertension News:

Anti-Hypertensive Drugs Cut Cardiac Events in Heart Disease Patients With Normal Blood Pressure

Administration of blood pressure lowering medication to heart disease patients with a normal blood pressure dramatically reduces their risk of adverse cardiac events and slows heart disease progression, according to a new study led by The Cleveland Clinic.

In the study involving 1,991 patients, researchers enrolled patients with coronary heart disease and an average blood pressure of 129/78, which is considered completely normal by current standards. Patients were given one of two types of blood pressure lowering drugs, the calcium channel blocker amlodipine (Norvasc®) or the ACE inhibitor enalapril (Vasotec®), or a placebo.

After two years of treatment with amlodipine, patients had a 31% reduction in major adverse cardiovascular events, including heart attack, stroke, death, hospitalization for chest pain and need for angioplasty or bypass surgery. Although the group receiving enalapril experienced a 15-percent reduction in adverse events, the difference was not statistically significant. In both the amlodipine and enalapril groups, blood pressure was reduced about 5/3 mm Hg to approximately 124/76.

In the group that received a placebo, more plaque had built up in the coronary arteries at the end of 24 months. In the group that received amlodipine, no disease progression occurred. The differences were particularly dramatic in patients with starting blood pressures above the mean of 129/78.

Lead researcher Steven Nissen, M.D., a Cleveland Clinic cardiologist, said the study demonstrates the critical importance of lowering blood pressure in patients with heart disease and suggests that current guidelines do not go far enough in recommendations for blood pressure targets in patients with coronary disease.

“This is the first study to demonstrate that blood pressure reduction can slow or halt the buildup of plaque in the coronary arteries,” Nissen said. “Previously, only cholesterol lowering drugs have been shown to slow disease progression. The current study demonstrates that blood pressure lowering drugs produce similar benefits.”
         
One of the surprises in the study, Nissen said, was the greater effect of the calcium channel blocker, amlodipine, compared with the ACE inhibitor, enalapril. He suspects that the longer duration of action of amlodipine likely explains the difference. “Because enalapril is shorter-acting, it may not have reduced blood pressure for the full 24 hours with once-per-day administration,” he said.

Source: Medical Week staff, week of November 13, 2004