Approved Research

Nutrition, physical activity, atrial fibrillation: how good are the benefits and what are the underlying cardiovascular mechanisms ?

Lay summary

A key characteristic of the heart is its regular rhythm. When the heart is exposed to irregular electric impulses, such as with atrial fibrillation (AF), detrimental effects can occur affecting the ability of the heart to pump blood. AF affects more than 33 million individuals worldwide, and places individuals at increased risk for stroke, heart failure and death. Of note, being fit seems to protect the long-term severity of AF, and individuals with AF who improved their aerobic fitness seem to decrease their severity of atrial fibrillation. Although physical activity is known to stay far from cardiovascular events, there are limited data investigating the benefits of physical acitivity on the reduction of AF burden.

Once AF is present, regular exercise in these patients reduces the risk for developing cardiovascular events. Moreover, an vigorous physical activity/high intensity exercise training seems to bring greater adaptations in cardiac patients. This effect may be related to improvements in vessels and heart functions and structures. No previous study has explored this possibility in patients with AF. Therefore, the cardiovascular mechanisms to explain how physical activity benefits on AF reduction are unknown. Better insight into how intensity of exercise training could affect the heart and the blood vessels can lead to better exercise recommendations in this population.

Diet is another approach to reduce AF incidence/recurrence. Yet, robust evidence exists for weight loss, for both reduction of AF risk and optimisation of AF management outcomes. Using a personalised approach to improve weight loss has been raised because of the individual response to diet. This concept has never been investigated on recurrence of AF.

Several benefits can be raised from our studies. First, our study will help to clearly understand the relation between physical activity, cognition, and AF. Second, it will help to understand what are the cardiovascular and cerebral physiological adaptation to physical activity that contribute to a lower recurrence of AF or cognitive dysfunction. Third, our study will gain insights into biological mechanisms which would otherwise be impossible to determine using established risk markers alone. Fourth we will be able to explore the relationship between diet and recurrence of AF. This project will contribute to improved clinical care for patients with AF, specifically related to the prescription of the optimal dose and type of exercise. This may result in fewer complications, improved quality of life, and lower socio-economic/healthcare costs.