Doctors are warning New Yorkers with heart conditions to take extra precautions as smoke from Canadian wildfires impacts the air in New York City.

Health officials advise patients with a history of heart disease to avoid strenuous activities outdoors until the air quality returns to normal. They say it's safer to spend time inside places with air conditioning and clean air circulation. They also strongly recommend wearing an N95- or KN95-grade mask when going outside since the polluted air can exacerbate underlying cardiac problems.

"The pulmonary system of the lungs really ties hand in hand with the cardiac system and the heart. The delivery of oxygen is really required for all organs, more specifically the heart and the lungs. If any of those are compromised in any fashion, one affects the other," says Dr. Elias Youssef, NYC Health + Hospitals .

During the hazy conditions, doctors say anyone with underlying respiratory and heart conditions should monitor their symptoms closely as well as seek medical attention earlier than they normally would.