If you or your healthcare team thinks that you may have atrial fibrillation, you will be diagnosed based on your medical and family history, a physical exam, and results from a variety of tests and procedures that your doctor may select. Since atrial fibrillation doesn’t always cause signs and symptoms, your doctor will want to figure out what is causing your condition so that you can be properly diagnosed and properly treated.

Before your appointment

There are a few things that you may want to keep in mind before you go to the doctor’s office for an appointment to test you for atrial fibrillation Contact your doctor’s office to be sure that there are no pre-appointment restrictions to your diet or any other lifestyle aspect. Take note of the symptoms that you are experiencing so you can be sure to give your doctor a full picture of any signs of atrial fibrillation you have. (You may even want to write these down.) You may also want to be prepared with a list of any medications you are taking.

It’s also always a good idea to bring a friend or family member to a doctor’s appointment to help you ask questions and to act as a second set of ears and memory for any instructions that the doctor may give you.

Personal and family medical history

Your doctor will want to know about any symptoms that may be related to atrial fibrillation or another heart condition as well as anything out of the ordinary that you have noticed in your health. Signs and symptoms that you may report should include: palpitations, dizziness, shortness of breath, swollen ankles, chest pain, history of heart disease, high blood pressure, lung disease, diabetes, or thyroid problems. It is also helpful for your doctor to know about any family history with atrial fibrillation, heart disease, or high blood pressure.

Physical exam

A physical cardiac exam will be relatively simple. Your doctor will want to listen to the rate and rhythm of your heartbeat, take your pulse and blood pressure reading, check for signs of heart muscle or valve problems, listen to your lungs, and check for signs of hyperthyroidism (too much thyroid hormone) like swelling in your legs or feet and an enlarged thyroid gland.

Tests and procedures

Although not a comprehensive list of all the tests and procedures that your doctor may suggest to confirm a diagnosis of atrial fibrillation or to look for other heart problems, these are the most common tests for atrial fibrillation:

Electrocardiogram (EKG or ECG)
This is the most common test for atrial fibrillation. A standard EKG records your heartbeat for a few seconds and monitors how fast your heart is beating and the steadiness or irregularities of the rhythm as well as the strength and timing of your heart’s electrical signals.

Holter and Event Monitors
Because a standard EKG only records your heart’s electrical activity for a short amount of time, it won’t be able to detect symptoms of atrial fibrillation that do not occur during the test. You may instead be asked to wear a Holter or event monitor to record your heart’s electrical activity. Both are attached via small patches called electrodes on your chest and connect to a small portable recording device that you can wear clipped to a belt, in your pocket, or hung around your neck. Both are worn during normal daily activities, however a Holter is worn for 24 or 48 hours and monitors you continuously, while an event monitor is wor for a week or until symptoms occur and records your heart’s electrical activity when you activate it (as you feel symptoms) or in some cases when it detects a change in your heart’s rhythm.

Stress test
For some heart conditions, it is easier to detect problems when your heart is working hard and beating quickly. During a stress test, your heart will be monitored while you perform physical activity (usually something like running on a treadmill in a lab) or if you are unable to exercise, you can be given a medicine that will force your heart to work harder.

Echocardiography (echo)
During an echo test, a device is moved back and forth across the chest as special sound waves bounce off the structures of your heart to create a moving picture of your heart on a lab screen. This helps the doctor to see the size and shape of your heart and to see how well your heart chambers and valves are working. Seeing this will allow your doctor to identify areas where there is poor blood flow to the heart or where areas of the heart muscle aren’t contracting normally.

Chest x-ray
A simple chest X-ray will show the your heart and lungs. This is important because with atrial fibrillation, you may have fluid buildup in your lungs, which can be a sign of atrial fibrillation complications.

Blood test
A blood test is done for your doctor to look for thyroid problems or other substances in your blood that may be causing atrial fibrillation. Knowing the cause of your atrial fibrillation helps your doctor to properly diagnose and treat your condition.