Doctors & patients are saying about 'A-Fib.com'...

"A-Fib.com is a great web site for patients, that is unequaled by anything else out there."

Dr. Douglas L. Packer, MD, FHRS, Mayo Clinic, Rochester, MN

"Jill and I put you and your work in our prayers every night. What you do to help people through this [A-Fib] process is really incredible."

Jill and Steve Douglas, East Troy, WI

“I really appreciate all the information on your website as it allows me to be a better informed patient and to know what questions to ask my EP.

Faye Spencer, Boise, ID, April 2017

“I think your site has helped a lot of patients.”

Dr. Hugh G. Calkins, MD Johns Hopkins,
Baltimore, MD

Doctors & patients are saying about 'Beat Your A-Fib'...

"If I had [your book] 10 years ago, it would have saved me 8 years of hell.”

Roy Salmon, Patient, A-Fib Free,
Adelaide, Australia

"This book is incredibly complete and easy-to-understand for anybody. I certainly recommend it for patients who want to know more about atrial fibrillation than what they will learn from doctors...."

Pierre Jaïs, M.D. Professor of Cardiology, Haut-Lévêque Hospital, Bordeaux, France

"Dear Steve, I saw a patient this morning with your book [in hand] and highlights throughout. She loves it and finds it very useful to help her in dealing with atrial fibrillation."

Dr. Wilber Su,
Cavanaugh Heart Center, Phoenix, AZ

"...masterful. You managed to combine an encyclopedic compilation of information with the simplicity of presentation that enhances the delivery of the information to the reader. This is not an easy thing to do, but you have been very, very successful at it."

Ira David Levin, heart patient,
Rome, Italy

"Within the pages of Beat Your A-Fib, Dr. Steve Ryan, PhD, provides a comprehensive guide for persons seeking to find a cure for their Atrial Fibrillation."

Walter Kerwin, MD, Cedars-Sinai Medical Center, Los Angeles, CA

Learn the Basics: Understanding the ECG/EKG Signal

Published March 28, 2025

One of our most popular pages on A-Fib.com is Understanding the ECG/EKG Signal. The post last week about the Vektor Medical vMap system that uses the common ECG to locate non-PV A-Fib triggers made me think it may be time to review the ECG.

Every patient with Atrial Fibrillation is familiar with a electrocardiogram, ECG. But most don’t know how to read their ECG signal strip. First, what is an electrocardiogram?

Schematic diagram of normal sinus rhythm for a human heart as seen on ECG; From Wikimedia; By Created by Agateller (Anthony Atkielski), converted to svg by atom. http://commons.wikimedia.org/wiki/File%3ASinusRhythmLabels.svg [Public domain], via Wikimedia Commons

Schematic diagram of normal sinus rhythm as seen on ECG

An electrocardiogram, ECG (EKG), is a test used to measure the rate and regularity of heartbeats, as well as the size and position of the chambers, the presence of any damage to the heart, and the effects of drugs or devices used to regulate the heart.

The ECG signal strip is a graphic tracing of the electrical activity of the heart. It measures the length of time it takes for the initial impulse to fire at the Sinus Node and then ends in the contracting of the Ventricles. ->Continue reading about the electrocardiogram->