We chat with Hong Kong cardiologist DR CHAN PAK HEI about a very common heart complaint, atrial fibrillation (AF); plus we look at AF treatment options – and some interesting new mobile phone technology that can help detect it.
What is atrial fibrillation, or AF, and how common is it?
Atrial fibrillation is a kind of cardiac arrhythmia; among all the different types of arrhythmia, it’s the most common.
Are certain age groups, genders or ethnicities at particular risk?
There are many risk factors associated with trial fibrillation; among these, advanced age is a very important one. We commonly observe elderly people to have a higher percentage of cases of atrial fibrillation. Also, men tend to develop atrial fibrillation more easily than women. As for the different ethnic groups, AF is more prevalent among Caucasians.
What are the symptoms?
Atrial fibrillation can be asymptomatic; in fact, studies suggest that as many as 30 to 40 percent of people diagnosed with AF are asymptomatic. Those who do have symptoms might find that they easily develop fatigue and tiredness; or that when they exercise or exert themselves, they easily develop a shortness of breath or chest discomfort. Sometimes, they’ll have feelings of irregularities in their heartbeat; we refer to these as palpitations.
Can you have a regular heart rhythm and still have AF?
There are different forms of atrial fibrillation; it can come and go – we label that as paroxysmal atrial fibrillation (as opposed to persistent atrial fibrillation). During the period when the patient is not having atrial fibrillation, their heart rhythm is regular. Then, when they develop an attack, they’ll have feelings of irregularities in their rhythm.
Why is it important to diagnose and treat AF?
Atrial fibrillation is associated with an increased risk of stroke. Compared to those who have similar risk factors but don’t have AF, people with atrial fibrillation actually have a five-fold risk of ischemic stroke.
Who should be screened for the condition?
The purpose of screening and detecting atrial fibrillation is to implement preventive strategies. Since people with risk factors such as diabetes, hypertension and advanced age tend to have a high risk of suffering a stroke when they develop atrial fibrillation, these are the groups we should initially consider for screening.
How is screening carried out? Tell us about any technological advances in this area
When a patient’s atrial fibrillation is active, we can easily detect the rhythm of the AF by checking the pulse of the patient, or via a simple 12-lead ECG. As I mentioned, atrial fibrillation can come and go. This is why making a diagnosis can sometimes be difficult. Strategies such as getting the patient to wear a Holter monitor for a duration of 24 or 48 hours, or even longer, can help us to detect attacks of AF.
Of course, most people will have limited access to these types of screening or detection strategies. Thanks to technological developments, however, they can now take advantage of handheld devices for doing what’s known as a “single-lead ECG”. These gadgets and devices include the Kardia, the Apple Watch and others. Patients can check themselves for atrial fibrillation when they have palpitations by doing a single-lead ECG by connecting to these devices. The latest blood pressure machines that you can buy in shops will also often incorporate pulse-checking algorithms; these can help us screen for AF and make a diagnosis.
What does “PPG” refer to in terms of AF detection?
As we know, atrial fibrillation generates a variability in the pulse and the pulse volume. During attacks of AF, what’s known as photoplethysmography or PPG technology can actually detect the variation in the pulse by employing the reflection of light. By using a mobile phone app and the phone’s backlight and camera, we can see reflections and different variabilities to calculate if you have underlying atrial fibrillation. Since these apps are very easily accessible, it means you don’t even need an additional device like a blood pressure cuff or an Apple Watch to pick up AF or other cardiac arrhythmia easily.
What treatment is there for AF?
Early diagnosis of atrial fibrillation is very important, so we can implement preventive strategies – treatment depends on whether the patient is symptomatic. If they’re not symptomatic, we don’t actually have to consider any rate or rhythm control strategies. For patients who are symptomatic, we have to see whether the symptoms are brought on by the irregularities of the rhythm or just on account of the rate of the atrial fibrillation; this allows us to implement different medicines, or even consider atrial fibrillation ablations to ameliorate their symptoms.
The other very important aspect of atrial fibrillation treatment is stroke prevention. In particular, the early use of anticoagulants in AF treatment can prevent patients from suffering from ischaemic stroke.
What are some things we can do from a health perspective to prevent AF?
As I’ve mentioned, atrial fibrillation has various risk factors; these include advanced age, diabetes, hypertension, obstructive sleep apnea, other cardiac diseases, cigarette smoking and also alcohol consumption. Some of these factors are largely preventable by implementing a healthy lifestyle. For example, by keeping our body weight at the normal level and doing regular exercise, we can help prevent some of the common risk factors and reduce the chance of developing AF.
Dr Chan Pak Hei is Honorary Consultant in Cardiology and Honorary Clinical Assistant Professor at the Department of Medicine, The University of Hong Kong.
This article first appeared in the Summer 2022 issue of Expat Living magazine. Subscribe now so you never miss an issue.