Atrial Fibrillation Video Series: Day Five
How Do We Detect AF?
By now, you know why taking atrial fibrillation seriously is important. But how do we actually find out if someone has AF? Many people are diagnosed only after a doctor runs some tests. Let’s demystify how AF is diagnosed and what you might expect during the process.
The most common and straightforward test is an Electrocardiogram (ECG). This is a quick, painless test where small sticky patches (electrodes) are placed on your chest, arms, and legs to record the electrical signals of your heart. It usually takes just a few minutes. On an ECG, AF has a distinctive signature: instead of neat, regular waves, it shows irregular squiggly lines for atrial activity and an irregular pattern of beats. One ECG can confirm AF if it’s happening at that moment.
However, AF can be sneaky – if it comes and goes (remember paroxysmal AF from earlier), it might not show up during a short doctor’s visit. If you have symptoms that suggest AF but a regular ECG doesn’t catch it, doctors may recommend longer monitoring. This could be a Holter monitor, which is basically a portable ECG you wear for 24-48 hours (or even up to a week). It continuously records your heart rhythm as you go about your daily life, increasing the chance of capturing an AF episode. There are also event recorders you can wear for weeks, which you activate when you feel symptoms, and even implantable loop recorders placed under the skin that can monitor for a year or more.
In recent years, technology has given us consumer devices too. Some smartwatches and phone apps can detect irregular pulses and have alerted people to possible AF. While these are not 100% diagnostic, they’re amazingly useful prompts to get a medical check. If your watch flags an irregular rhythm, a formal medical test like an ECG is warranted.
Alongside rhythm monitoring, your doctor will likely do a check-up and some other tests. Expect questions about your symptoms and medical history, and a physical exam (listening to your heart and lungs). You may have blood tests to look for triggers or risk factors (like thyroid function or electrolyte levels). An echocardiogram (an ultrasound of the heart) is also commonly done after an AF diagnosis – not to detect AF itself, but to see your heart’s structure and function. It helps identify any underlying heart disease (for instance, valve issues or enlarged atria) and it’s important for planning treatment.
Bottom line: Diagnosing AF might be as simple as one office ECG if you’re in AF at the time, or it might require some clever sleuthing with devices that track your heart over days or months. If you’re going through this process, hang in there – it’s worth the effort to know exactly what your heart is up to.
In our next email: We’ll discuss the different types of AF (paroxysmal, persistent, permanent) and why knowing which type you have matters for your treatment plan.
