A Matter of the Heart: EKGs
Pamela Tronetti. D.O., AGSF, director of the Senior Consultation Center, specializes in geriatric medicine at Parrish Medical Center, is a member of Parrish Medical Group, and a contributing columnist for Florida Today Newspaper.
A version of this article appeared in print by Florida Today newspaper.
“So when did you have this heart attack?” I asked, looking up from the EKG.
I knew by the look on her face that the next words out of her mouth were going to be. “What heart attack?” Oh my. I wondered if the EKG tracing was mapping out the scars from a silent heart attack, or if it was a falsely positive result because she was a buxom woman. I would have to figure this out.
The EKG (from the German Elektrokardiogramm) represents the best technology of the 80s—the 1880s that is. It was actually pretty ingenious. Scientists realized that each heartbeat creates a tiny electrical charge, which can be detected by electrodes on the skin.
Although the result looks like a seismograph, the size and shape of each peak and valley tell a story. By looking at an EKG, we can tell if the heartbeat is regular, or if there are dangerous extra beats or pauses. We can estimate the size of the heart based on the height of the peaks. And of course, an EKG can disclose an impending or recent heart attack.
The Latin word for heart muscle is myocardium. Infarction means that a blood vessel is obstructed and the tissue it is feeding is damaged. A myocardial infarction (MI) means that an artery feeding an area of the heart has become obstructed and the heart muscle has been damaged—a heart attack. An EKG can also show evidence of scar tissue from a previous MI. But it can’t tell us when it happened.
Why does the EKG pattern change when there has been a previous heart attack? The normal electrical impulse travels from the heart muscle to the surface of the body at a certain pattern and speed. The impulse moves more slowly through scarred or damaged heart muscle, so it leaves a telltale pattern that indicates that a heart attack has occurred.
Guess what else slows down the electrical impulse? Breast tissue. So, many women have an abnormal EKG that appears to show a previous heart attack. On the other hand, diabetics are prone to silent heart attacks. They can have extensive damage and not feel it.
Elderly people don’t always have the classic left-sided crushing chest pain radiating down to the left arm that is typical of a heart attack. They may feel short of breath, weak, or nauseated. Yes, nausea can be the only sign of a serious heart attack.
Now, point to the tip of your breastbone. Above your hand is your heart. Below your hand is your stomach. A heart attack is a muscle cramp. If the attack is on the inferior wall (doctors say superior and inferior to mean top and bottom) then the pain radiates downwards and causes nausea and vomiting.
One of my pet peeves is that many people who should be getting routine EKGs are not. I meet people who had open-heart surgery 10 years ago and haven’t had an EKG since. I also meet people who are in their 70s and 80s who don’t remember ever having an EKG.
If you have a history of heart disease, shortness of breath, palpitations, diabetes, high blood pressure, high cholesterol, or other risk factors, you should ask your doctor about an EKG. I am very happy that part of the Medicare Welcome Physical for new members includes an EKG.
So, did my lady have a heart attack? A nuclear stress test disclosed that she had suffered a small heart attack, as the EKG said, and was at risk for another. Within a week she had a cardiac catheterization, a stent, and a new appreciation for the fragility of life.