By STEVE STERNBERG
Gannett News Service

Car and truck exhaust fumes — specifically the particles spewing from millions of tailpipes — pose a serious risk to people with heart disease, a new study says.

The preliminary study is the first to link highway pollution with exercise-induced oxygen starvation, which can bring on a heart attack in people with heart disease.

About 12.4 million people in the United States have coronary heart disease, the nation’s leading killer. The disease claims about a half-million lives annually, according to American Heart Association statistics.

The results provide the first “biological link” between exhaust particles and sickness and death from coronary heart disease, lead researcher Juha Pekkanen, of the National Public Health Institute in Kuopio, Finland, and his colleagues say.

Their study appeared in an online version of the journal “Circulation.”

Previous studies have explored the relationship between car and truck pollution with heart disease.

“It’s a novel exploration, and it has opened new avenues for thinking about air pollution and heart disease,” says George Sopko, a cardiologist at the National Heart, Lung and Blood Institute.

“The problem of particulate air pollution is pervasive and growing,” add Richard Verrier, Murray Mittleman and Peter Stone of Harvard Medical School in an editorial in the medical journal.

The Harvard team predicts a greater impact from “this insidious contributor to heart disease” as traffic worsens and more baby boomers get heart disease.

The study was small, involving just 45 Finnish heart patients. The patients kept symptom diaries and visited their doctors twice a week. During each visit, the patients were given an electrocardiogram (ECG) during a six-minute bicycle exercise test. The ECG results, which detect electrical abnormalities linked to oxygen deprivation, were correlated with an analysis of the air near each patient’s home.

The analyses linked “significant” oxygen deprivation with the ultrafine and fine particles from car and truck exhaust pipes. “You can detect these particles in the bloodstream, that’s the fascinating part,” Sopko says. Researchers found no link to pollens or “soil-derived” particles.

Drugs called beta-blockers, which boost the heart’s blood supply, provide some protection. But doctors say many questions remain to be resolved. Among them: Which particles are the worst offenders? How do particles affect the heart? Are healthy people also at risk?