AF Symposium 2017
New Insights into the Effects of Obesity on Atrial Fibrillation
Dr. Jose Jalife of the University of Michigan, Ann Arbor, MI, discussed the “Obesity Paradox”. The Paradox is a hypothesis that obesity may be protective and associated with greater survival with certain chronic diseases. Dr. Jalfie showed how and why this is not the case with Atrial Fibrillation.
Under normal conditions, the surface of the heart (epicardium) is covered by fat stored in the tissue (called adipose tissue).
A-Fib is often associated with increased volume of epicardial fat. This increased volume lengthens the duration of A-Fib episodes and results in fibrotic remodeling of the adipose tissue.
In addition, fatty acids both shorten the ‘action potential’ and increase the ‘dominant frequency’ (factors in the initiation and maintenance of AF signals). This leads to fibrosis (fibrofatty infiltration) of the epicardial fat. Altogether, they perpetuate Atrial Fibrillation signals and episodes.
“Obesity Paradox” Doesn’t Apply
Excessive epicardial fat is bad for those with A-Fib. Thanks to Dr. Jalife’s research, we can rule out the “Obesity Paradox” with regards to obesity and A-Fib. Increased epicardial fat:
• Increases the duration of A-Fib
• causes fibrotic remodeling of the adipose tissue
• Increases fatty acids
Thanks to Dr. Jalife we are beginning to understand how and why obesity affects the heart and A-Fib.
Surgery of Obese Patient―My Observations
At a 2016 conference in Zürich, I watched a live A-Fib surgery of an obese patient. It was incredible how many layers of yellow fat bundles the surgeon had to cut through before reaching the heart.
If a video of this surgery were shown to A-Fib patients who are significantly overweight, it could be quite motivating. When you actually see the epicardial fat layers Dr. Jalife talks about, it makes a frightening, ‘come-to-Jesus’ impression.
What Patients Need to Know
Weight Loss and A-Fib: Research has shown that just losing weight and exercising, by themselves, can reduce and even eliminate A-Fib.
Recurrence Rates: In addition, many EPs today won’t perform a catheter ablation on someone who is obese, because their recurrence rates are very high compared to normal patients.
If you have A-Fib and are significantly overweight (not just a few pounds), you can expect to hear a lecture from your EP/doctor that you should lose some weight.