(RxWiki News) Non-obstructive coronary artery disease may show little or no signs of artery blockage, but it can still prove deadly. Blood pressure medication may lower the mortality risk for these patients.
When a patient has obstructive heart disease with clear signs of artery blockage, the health risk is obvious. The risks of non-obstructive heart disease can seem less apparent, but the condition increases the chances of dying if left untreated.
A new study has found that individuals with non-obstructive coronary artery disease (CAD) may reduce the risk of dying by taking angiotensin-converting enzyme (ACE) inhibitors — a common high blood pressure medication. These patients, however, are less likely to receive ACE inhibitors compared to those with obstructive CAD.
"Ask a doctor about treating non-obstructive heart disease with ACE inhibitors."
Raffaele Bugiardini, MD, in the Department of Experimental, Diagnostic and Specialty Medicine at the University of Bologna in Italy, led research on 1,602 patients who had acute coronary syndrome (ACS) — a term used for situations where blood to the heart muscle is suddenly blocked, such as a heart attack.
A total of 1,252 had obstructive CAD with blockage in the diameter of blood vessels greater than 50 percent, and 350 had non-obstructive CAD, where there was narrowing in the diameter of the blood vessels of 50 percent or less.
At discharge from the hospital, about 78 percent of individuals with non-obstructive CAD were taking beta-blockers compared with about 63 percent of obstructive CAD patients. A lower percentage of non-obstructive CAD patients (57.7 percent), however, were taking ACE-inhibitors prescriptions compared with 66.4 percent in the obstructive CAD group.
ACE inhibitors decrease the production of angiotensin, a hormone that causes the blood vessels to contract and raise blood pressure. Beta blockers block the effects of the hormone adrenaline, causing the heart to beat slower and less force.
Following up with patients at six months after discharge from the hospital, investigators discovered that far fewer non-obstructive CAD patients (3.1 percent) had died compared with obstructive CAD patients (20.6 percent).
Scientists noted that ACE inhibitors were clearly connected to a lower six-month mortality rate among those with non-obstructive CAD group, dropping the risk of dying by about 31 percent compared to those not taking ACE inhibitors. Researchers, however, found no link between beta-blockers and death in this group.
In the obstructive CAD group, both ACE inhibitors and beta-blockers were tied to lowering the risk of dying at the six-month mark. The risk of dying was lowered by almost half.
“ACE-inhibitor therapy seems to be an effective first-line treatment for preventing the occurrence of mortality in patients with non-obstructive CAD,” concluded the authors.
The study was published in March in The American Journal of Cardiology.