Irregular heartbeat? It could be a heart condition that greatly increases the risk of stroke

SINGAPORE – In 2003, Mr Tan Check Wan woke up to a tightness in his chest. His wife, who was a trained nurse, checked his pulse and, finding it irregular, decided that he needed to be taken to hospital immediately for treatment.

But his heart rhythm returned to normal, and the doctors could not find any irregularities with an electrocardiogram (ECG) – or even after monitoring his condition with a wearable device he wore for a week after discharge.

Later in the year, Mr Tan, now a 76-year-old retiree, felt his heart beating irregularly again after exercising.

He went to the hospital on his cardiologist’s advice and was diagnosed with atrial fibrillation through ECG tests.

Atrial fibrillation is a heart condition in which specialised heart muscles in the right atrium – the upper right chamber of the heart – which normally regulate the heartbeat by sending electrical signals to the other heart muscles, start firing erratically.

This causes the left and right atria to quiver instead of contract, so the heartbeat becomes irregular, and blood is not pumped into the heart’s lower chambers and subsequently out to the rest of the body efficiently.

Blood can pool in the lower left atrium, forming clots.

Patients with atrial fibrillation must have the condition properly managed, as it leads to a fivefold risk of stroke, the Singapore Heart Foundation (SHF) said.

Clinical Associate Professor Ching Chi Keong, SHF’s honorary secretary, said this is because the clots may dislodge and circulate around the body, including to the brain. If this subsequently leads to blockage of a blood vessel carrying blood to the brain, it may trigger a stroke.

Some patients persistently suffer from symptoms, such as palpitations, breathlessness, chest pain, dizzy spells or fatigue.

But atrial fibrillation can also be hard to detect, especially in those who do not have symptoms, unless the condition is detected during regular screenings that include an ECG.

In addition, some patients could experience brief and intermittent episodes of abnormal heart rhythm, which return to normal on their own, sometimes without intervention.

But such patients can experience unpleasant symptoms during episodes of abnormal rhythm, as in the case of Mr Tan.

Patients with atrial fibrillation may be prescribed medication such as beta-blockers or calcium channel blockers to slow the heartbeat and help the heart pump more efficiently.

Blood thinners may also be prescribed to prevent blood clots and lower the risk of stroke.

Some patients may also be suitable for a non-surgical procedure known as catheter ablation, which uses radiofrequency energy to destroy the abnormal site in the heart causing the arrhythmia, or abnormal heart rhythm, Prof Ching said.

Atrial fibrillation is more likely to affect people with certain medical conditions, including high blood pressure and hyperthyroidism caused by an overactive thyroid gland.

Lifestyle changes such as regular exercise, a healthy diet and stopping smoking will also help in managing the condition, according to the SHF.

On this front, Mr Tan has been regularly attending the weekly exercise sessions at SHF’s Heart Wellness Centre in Bishan since 2010, which have helped keep his blood pressure in check and make new friends.

Cardiac patients and those at risk of cardiac conditions can join the SHF programme with a doctor’s assessment. SHF currently charges $50 for 10 sessions, subsidised by donations from the public.

Prof Ching said international studies showed that the incidence rate of atrial fibrillation increases with age, where it affects about one in 1,000 individuals aged 50 years and younger, but one in 10 for those aged 80 and above.

A study of 40,602 patients diagnosed with atrial fibrillation in Singapore from 2008 to 2015 found that the condition affects 0.6 per cent of adults aged between 45 and 64 years here.

Among those aged over 65 years, the rate is more than 10 times higher, at 7 per cent.

Anecdotally, there are also more younger patients diagnosed with atrial fibrillation, some as young as their late 30s, said Prof Ching, who is also a senior consultant at the cardiology department at the National Heart Centre Singapore.

But this does not mean that more people are developing the condition, but rather that more are getting diagnosed owing to better awareness of heart health in general, he said.

In addition, more people are wearing smartwatches, which can detect irregular heart rhythms.

There are also more blood pressure monitors available that can detect irregular heartbeats when measuring blood pressure.

Besides the age factor, Prof Ching said epidemiological studies also showed that men are at least 1.5 times more likely to develop atrial fibrillation.

The local study, published in September 2022 in The Annals – the medical journal of the Academy of Medicine, Singapore – similarly showed higher rates of atrial fibrillation in men.

In addition, it found that Malays had the highest age-standardised atrial fibrillation incidence rate, followed by Chinese and Indians. The research team said rates among Malay women were even higher than among Indian men.

Prof Ching said at-risk individuals can use smartwatches with an ECG feature to measure the heart’s electrical activity and watch out for irregular heart rhythm or possible symptoms.

“Those diagnosed with atrial fibrillation have to be prepared for long-term medication, but it is not a death sentence. There are ways to mitigate, control and reduce complications, and to live well even with atrial fibrillation,” he said.