How is it possible for an elderly person (over age 65) to have a low resting heart rate along with severe coronary artery disease (CAD)?

Before my mother had CABG x 5, her resting heart rate was often in the high 60s, giving her the illusion that she had a healthy heart! After she had the surgery, I learned that her ejection fraction was 35 percent.

So I was thinking, here we have an elderly patient with severe heart disease plus a low ejection fraction—yet a pre-surgical resting heart rate in the high 60s.

I’d think that her conditions would have made her heart beat fast since its “squeeze” was only 35 percent, and the coronary arteries were quite narrowed.

In fact, many very out-of-shape people have slow resting heart rates, or at least pulses in the high 60s (which is very slow for them), while there are younger gym rats with resting pulses in the 80s. What’s going on here?

What a Cardiologist Says

“The heart has one main internal pacemaker that generates the electrical charge that leads to the heartbeat or heart contraction,” says cardiologist and internal medicine specialist Norman E. Lepor, MD, who’s with Cedars Sinai in Beverly Hills, CA.

“As part of aging, this internal, called the sino-atrial node, can fatigue and slow down the electrical discharge.

“If the heartbeat slows to the point that one becomes dizzy or faints, an artificial pacemaker implantation is often performed to resolve this.

“In patients with coronary artery disease, a slow heartbeat can also be caused by medications that are used to treat angina or chest pain symptoms (my mother was not on any cardiac medications prior to surgery, so presumably her sino-atrial node was persistently fatigued).

“Common medicines that are used in these patients that can slow heartbeat include beta blockers (metoprolol, atenolol, carvedilol.) and some calcium channel blockers (verapamil, diltiazem).”

Having performed over 4,000 coronary angiograms and angioplasties, Dr. Lepor has focused on prevention and treatment of coronary heart disease. 
Lorra Garrick has been covering medical, fitness and cybersecurity topics for many years, having written thousands of articles for print magazines and websites, including as a ghostwriter. She’s also a former ACE-certified personal trainer.  

.

Top image: Shutterstock/Alexander Raths