Yes, there are a few key differences between a resting ECG and an exercise ECG. An ECG (electrocardiogram) records the electrical activity of the heart and can help detect heart abnormalities.
What is a Resting ECG?
A resting ECG is performed while the patient is at rest, usually lying down. Electrodes are placed on the chest, arms, and legs to record the heart’s electrical signals. A resting ECG gives your doctor a snapshot of your heart health during normal day-to-day activity.
When is a Resting ECG Done?
A resting ECG may be ordered if you have symptoms like:
- Chest pain or discomfort
- Shortness of breath
- Dizziness or fainting
- Palpitations or irregular heartbeat
- Family history of heart disease
It can help detect issues like:
- Previous heart attack
- Enlarged heart chambers
- Abnormal heart rhythms (arrhythmias)
- Damage from a previous heart attack
- Congenital heart defects
What is an Exercise ECG?
An exercise ECG, also called a stress test, is performed while the patient is walking on a treadmill or cycling on a stationary bike. The test monitors the heart’s electrical activity during exertion or stress.
When is an Exercise ECG Done?
An exercise ECG may be ordered if you have symptoms like:
- Chest pain or tightness during activity
- Shortness of breath when active
- Risk factors for coronary artery disease
It can help:
- Diagnose coronary artery disease
- Assess the severity of coronary blockages
- Evaluate treatment like bypass surgery or angioplasty
- Determine safe levels of exercise after a heart attack
- Identify exercise-induced arrhythmias
Differences Between Resting and Exercise ECGs
Some key differences between resting and exercise ECGs include:
| Resting ECG | Exercise ECG |
|---|---|
| Performed at rest | Performed during exercise |
| Checks heart function at rest | Checks heart function during physical stress |
| Can detect arrhythmias at rest | Better at detecting exercise-induced arrhythmias |
| May miss signs of coronary artery disease | Better at detecting coronary artery blockages |
| Shorter test time (5-10 minutes) | Longer test time (10-20 minutes of exercise) |
Resting ECG Procedure
During a resting ECG, electrodes are placed on your chest, arms, and legs. These electrodes detect the tiny electrical signals produced when your heart beats. The signals are transmitted to the ECG machine, which prints out a graph of your heartbeat.
You will lie flat on an exam table, relax, and breathe normally during the test. The technician will clean certain areas with alcohol wipes and apply electrode stickers. For a 12-lead ECG, 10 electrodes are placed across your torso in specific spots.
You’ll be asked to remain still during the recording, which typically lasts 5-10 minutes. The technician may need to reposition electrodes to get a clearer reading. Some occasional deep breathing may be required.
Resting ECG Results
The ECG graph, with its series of spike-and-dome patterns, provides information about:
- Heart rate and rhythm
- Size of heart chambers
- Presence of any damage to the heart
Your doctor will look for signs of abnormal heart rhythms like atrial fibrillation, heart block, or ventricular tachycardia. Other findings can include enlarged heart, previous heart attack, electrolyte imbalances, and more.
Exercise ECG Procedure
An exercise stress test monitors the heart’s electrical activity while you engage in increasingly strenuous physical exercise. This allows the heart to be assessed under the type of exertion encountered during daily activities and exercise.
Preparation may involve not eating or drinking caffeinated beverages for a few hours prior. You’ll wear comfortable clothes and shoes suitable for exercise.
Electrodes are placed on your chest to monitor heart signals, as with a resting ECG. Your blood pressure will also be checked periodically. You’ll then walk on a treadmill or pedal a stationary bike.
The test begins with an easy workload, but the intensity slowly increases every few minutes. You’ll be monitored for any chest pain, fatigue, lightheadedness, or shortness of breath. The test continues until you reach your target heart rate.
If concerning symptoms appear, the test will be stopped. Otherwise, it typically lasts around 10-20 minutes. The cooldown period involves walking slowly for a few minutes as your heart rate returns to normal.
Exercise ECG Results
The ECG tracings during exercise will be compared to the resting ECG. Significant changes could indicate:
- Reduced blood flow through coronary arteries (ischemia)
- Heart rhythm abnormalities
- Problems with heart valve function
Ischemia often causes ST segment changes on the ECG. Your doctor will analyze at what level of exercise the changes occurred along with any symptoms reported.
Conclusion
While both resting and exercise ECGs are useful for evaluating heart health, each test provides unique information. A resting ECG gives a snapshot at rest, while an exercise ECG assesses how the heart responds to physical exertion.
An exercise stress test is better at detecting issues like coronary artery blockages that may not always appear at rest. However, a resting ECG can identify some arrhythmias and other abnormalities not connected to physical activity.
In many cases, healthcare providers will order both a resting ECG to screen for problems and follow up with an exercise ECG if concerns warrant a closer look during physical activity. The two tests can provide complementary information to help diagnose heart issues.