"It's possible that certain very small particles, or chemicals that travel with them, may reach the circulation and cause direct harm," Brook said. "The lung nerve-fiber irritation can also disrupt the balance of the nervous system throughout the body. These responses can increase blood clotting and thrombosis, impair vascular function and blood flow, elevate blood pressure, and disrupt proper cardiac electrical activity which may ultimately provoke heart attacks, strokes, or even death.

"These studies also indicate that there is no 'safe' level of PM2.5 exposure," he said.

Recommendations include:

Physicians should emphasize treatment of traditional cardiovascular risk factors, which may lessen patients' susceptibility to air pollution.All patients with cardiovascular disease should be educated about the risks of air pollution.Healthcare professionals should consider educating patients without cardiovascular disease but who are at high risk, such as the elderly, individuals with metabolic syndrome or multiple risk factors and those with diabetes.Based on air pollution levels, as forecasted by the Air Quality Index available in many media sources, recommendations for methods to reduce exposure and limit activity should be followed depending on the patient's level of risk.

Reducing exposure to air pollution takes effort at the population level by implementing national policies as well as at the individual level, Brook said. "People can limit their exposure as much as possible by decreasing their time outside when particle levels are high and reducing time spent in traffic “ a common source of exposure in today's world."

The American Heart Association and the Environmental Protection Agency are co-sponsoring a Congressional briefing on Capitol Hill to educate lawmakers about the link between air pollution and cardiovascular disease. The association plans to monitor opportunities at the state and federal level to decrease the amount of particulate matter air pollution.

SOURCE American Heart Association