Fatty acids cut heart-artery narrowing.

Fatty acids cut heart-artery renarrowing

A new study shows that heavy doses of fish-oil fatty acids may prolong the effectiveness of coronary angioplasty, a procedure in which narrowed heart arteries are enlarged by insertion and inflation of a tiny balloon.

In 25 to 40 percent of US. patients undergoing angioplasty, the opened arteries narrow again, often within three months. Various treatments tried so far have failed to help. But when researchers at two Dallas hospitals gave angioplasty patients a long-term dietary supplement of n-3 fatty acids--also known as omega-3 fatty acids and found in fish oil -- the incidence of arterial renarrowing decreased markedly.

Seven days before undergoing angioplasty, patients in an experimental group began a six-month course of treatment with 5.4 grams daily of n-3 fatty acids, in capsule form, in addition to a standard treatment of aspirin and dipyridamole, a drug used to prevent platelet clumping. A control group received only the standard treatment.

In 82 patients the researchers prformed angioplasty on 103 narrowed arterial passages. The extent of disease and reduction in narrowing were comparable in both groups.

Three to four months later, they found that 19 percent of patients in the treatment group and 46 percent of the control group showed signs of recurrence. They also observed significantly less renarrowing per blockage in the experimental group: 16 percent, compared with 36 percent in the controls. Follow-up for as long as a year showed no new symptoms of renarrowing in the treatment group, the researchers report in the Sept. 22 NEW ENGLAND JOURNAL OF MEDICINE.

Led by Gregory J. Dehmer, who is now at the University of North Carolina in Chapel Hill, the study was performed at the Dallas Veterans Administration Medical Center and the University of Texas Southwestern Medical Center at Dallas. It is significant, the researchers say, that the patients studied -- all of whom were male and most of whom smoke heavily--were at high risk for recurrence.

The role of n-3 fatty acids in preventing heart disease has been a subject at controversy (SN: 11/28/87, p.342; 7/23/88, p.52). Exactly how they discourage renarrowing of the arteries remains unknown. Nonetheless, the researchers say the new results suggest the treatment appears "safe and well tolerated" in a high-risk group and warrants large-scale testing to determine whether other patients will also benefit.