Elevated heart rate can trigger stroke in patients with severely blocked carotid arteries, researchers find. The research is published in the journal “Physics of Fluids”.

Conversely, for healthy people and those with only mildly clogged arteries, exercise is beneficial for maintaining healthy blood flow. In healthy patients, the increased heart rate increases and stabilizes the resistance force exerted by the blood on the vessel wall, reducing the risk of narrowing. But for patients who already have stenosis, it may not be as beneficial.

The researchers used a specialized computational model to simulate blood flow in the carotid arteries at three stages of stenosis, no occlusion, 30% mild occlusion, and 50% moderate occlusion. They compared the effect of an exercise-induced heart rate of 140 beats per minute, as well as resting heart rates of 67 and 100 beats per minute. For the healthy and mild cases, exercise improved the health of the simulated carotid artery, but the results for moderate occlusion were worrisome.

Many factors contribute to the risk of narrowing and stroke, including age, lifestyle and genes, but the authors recommend regular blood health screening for people who exercise vigorously. They also recommend a carefully prescribed exercise program for people with moderate to severe stenosis or a history of stroke.