Many people are familiar with fast heart rates, otherwise known as tachycardia. Typical diagnoses are atrial fibrillation, SVT, or sinus tachycardia.
But I have seen many hundreds of people over the years with a slow heart rate, otherwise known as bradycardia (brad-e-KAHR-dee-uh).
What is the normal heart rate?
The typical definition of normal is a heart rate between 60 to 100 beats per minute. Any number of beats below 60 is bradycardia. Heart rate above 100 is tachycardia. These numbers apply to a person at rest.
But the above definition is not a very good one. Healthy people who are physically active have heart rates in the 50's while at rest. Athletes often have resting heart rates in the 40's and some even the 30's!
When we sleep, our heart rate usually dips into the 30's and 40's. Our body demand for blood flow is minimal while we sleep.
How low is too low?
My mantra has always been that we are only “given” so many heart beats in a lifetime, so the less we use the better. In other words, don't worry about a number. Focus on symptoms. If you don't have any symptoms, there is typically nothing to worry about.
Symptoms are what matter here. If you have fatigue, lightheadedness, or shortness of breath with activity, that could be a sign that your heart rate is too low. Then we need to figure out why.
For example, if you are working in the yard doing chores and your heart rate is only 50 beats per minute, you may be short of breath. Yard work may require a heart rate of 80 to 100 beats per minute. If your heart cannot keep up with the demands your muscles and body are making, you will be short of breath or fatigue easily. Heart rate determines our cardiac output. If our heart cannot make the output, symptoms arise.
What causes low heart rate?
As we said above, a low heart rate is usually normal, especially in active and athletic people. But if the slow heart rate is causing symptoms, we need to figure out why.
Thyroid dysfunction is a common cause of slow heart rate. The thyroid and its hormone thyroxine stimulate the sinus node of the heart to fire an electrical impulse leading to a contraction of the heart muscle. Think of this hormone like a spark plug in your car. If someone is hypothyroid, they may have bradycardia. Fixing the thyroid or using hormone replacement usually is the fix.
Pharmaceuticals are the most common cause of bradycardia. Beta-blockers, calcium channel blockers and other cardiac drugs are the common offenders. Even beta-blocker eye drops can slow heart rate. I have seen several patients with symptomatic bradycardia have resolution of their issues with stopping eye drops.
Electrolyte imbalances of potassium, magnesium and calcium can lead to slow heart rate, so we need to check those levels.
Other causes include previous heart surgery and congenital (since birth) issues.
A Deep Dive on Cause
After we look at basic labs like thyroid and electrolytes, we need to go further. Something is interfering with the ability of the heart to meet the demands of the body. Here are some possibilities that need to be checked:
Mold mycotoxins- we use the Vibrant urine test that you can get here.
Nutrient deficiency or excess- we use the Vibrant micronutrient here.
It just makes common sense that those who lead the healthiest lifestyle would have the lowest risk of bradycardia. Improving your lifestyle can also improve your heart rate. Here are my suggestions:
Eat organic, Paleo foods. Give your body the nutrition it needs while avoiding what it doesn't. Head over to com/Paleo.
Sleep with the sundown and awake before the sunrise.
Get sunshine morning, noon and afternoon. Smart sun. Sunburn bad. Sunshine good.
Get active out doors.
Get away from chemicals.
Mental wellness. Reduce stress, anxiety, depression and anger.
There are not any pharmaceuticals to raise heart rate safely and effectively. There are some intravenous options for emergencies, but no long term solutions.
The only long term solution for bradycardia and slow heart rates is a permanent pacemaker. I have installed 100's of pacemakers in my career and this remains an effective and safe option for many.
But again, if given the time, I want to find the CAUSE of the slow heart rate and hopefully by reversing the cause, have improvement in heart rate and therefore not need a pacemaker.
How Can We Help?
If you have been told that your heart rate is too slow and we have time to discuss the situation, let's do it. Either in person or by phone, I can help you. Even if you have a pacemaker, the doctors never fixed the CAUSE. Let's work together because fixing the cause may prevent another health issue.
The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. It is intended as a sharing of knowledge and information from the research and experience of Dr. Zajackowski and her functional medicine community. Dr. Zajackowski encourages you to make your own health care decisions based upon your research and in partnership with a qualified health care professional.
Article Written By: Jack Wolfson DO, FACC - The Paleo Cardiologist