When most people think of heart tests, they think of the ECG. ECG stands for electrocardiogram. It's also called an EKG, from the German elektrokardiogram. Although it may look like an ECG is recording heartbeats, it's not. In fact, it records the electrical activity (the electrical triggers, if you will) that presage the actual heartbeat. The mechanical beats follow the electrical triggers by about a tenth of a second -- unless, of course, there's a problem. Or to state it in "medicalese," electrical systole and diastole precede mechanical systole and diastole (contraction and relaxation) of the heart by about a tenth of a second.
The ECG is an important tool for your doctor, but is hardly complete and comes with several limitations. …show more content…
- An abnormal reading doesn't necessarily mean that there is.
- It's merely a piece of the puzzle that can help point the doctor in a direction.
That said, an ECG provides four primary pieces of information for your doctor.
First, an ECG can show how fast your heart is beating -- or more accurately, how fast the electrical activity is moving through your heart. By measuring the intervals between beats, your doctor can determine if the electrical signal is moving through your heart too slow or too fast.
It also shows the strength and timing of the beat. By measuring the amount of electrical activity passing through your heart muscle, your doctor can get an indication as to which parts of your heart are too large or are overworked or if it's not pumping forcefully enough.
It can provide evidence of damage to various parts of the heart muscle caused by:
- Previous heart attacks.
- Congenital heart abnormalities.
- Diseases such as thyroid problems, rheumatic fever, diabetes, and high blood pressure.
- Inflammation to either the heart muscle or its lining (inside and …show more content…
In our ECG snippet (two graphics above), we can find such a point in the middle of the graph. A quick count to the right shows 5 large boxes, or approximately 60 beats per minute. Is that cool or what? You can now read a good chunk of an ECG -- and without going to medical school.
Seeing the Heart
Listening to your heart and monitoring its electrical activity, may not be enough. Your doctor may also want to see the heart, and there are several ways to do that.
The most basic heart picture is the chest X-ray. Skilled doctors can actually interpret a great deal from an X-ray, but that's also the problem with the technology -- it requires a great deal of interpretation. That means its accuracy, at times, can be less than desirable.
You can think of the arteriogram (AKA angiogram, angiograph, etc.) as an X-ray on steroids. It's a procedure that uses a special dye (contrast material) and X-rays to see how blood flows through your