Patients with atrial fibrillation, which can leave them at a higher risk of stroke, still need treatment even after their heart rhythm seems to have returned to normal, warn UK researchers.
Patients with the condition, which affects around 1.6 million people in the UK, may be aware of noticeable heart palpitations, noted the researchers.
“We can conclude that people with resolved atrial fibrillation continue to be at high risk of stroke”
But they also highlighted that sometimes atrial fibrillation did not cause any symptoms and a patient who has it can be completely unaware that their heart rate is irregular.
They highlighted that people with atrial fibrillation are much more likely to develop blood clots and experience strokes, and it was important for them to take drugs to prevent blood clotting.
In addition, they noted that sometimes atrial fibrillation appeared to go away and the heart goes back to its normal rhythm – the condition may then be deemed to have “resolved”.
The researchers said that in 2016 one in 10 people with atrial fibrillation – around 160,000 people in the UK – were classed to have had their condition resolved.
“Guidelines should be updated to advocate continued use of anticoagulants2
Up until now it had been unclear whether the clot-prevention drugs could be safely stopped when the condition was resolved in this way, said the study authors from the University of Birmingham.
They said their study had now found that patients whose heart rhythm returned to normal continued to be at high risk of stroke and should, as a result, continue to be treated.
Researchers looked at patient records from 640 general practices throughout the UK and compared the frequency of strokes in three groups of patients.
The study involved 11,159 patients with resolved atrial fibrillation, 15,059 controls with atrial fibrillation, and 22,266 controls without atrial fibrillation.
The study authors said: “Patients with resolved atrial fibrillation remain at higher risk of stroke or transient ischemic attack than patients without atrial fibrillation.
“The risk is increased even in those in whom recurrent atrial fibrillation is not documented,” they said in the British Medical Journal.
“Guidelines should be updated to advocate continued use of anticoagulants in patients with resolved atrial fibrillation,” they added.
“An increasing number of people are recorded as having atrial fibrillation as resolved”
Lead study author Dr Nicola Adderley said: “What we found was that strokes were least common in people who never had atrial fibrillation, and much more common in people whose records said their atrial fibrillation had been resolved.
“Significantly, in recent years, we found that strokes were nearly as common in people whose atrial fibrillation had resolved as in those with ongoing atrial fibrillation,” she said.
“Therefore, we can conclude that people with resolved atrial fibrillation continue to be at high risk of stroke,” she added.
The researchers also looked at patient treatment, specifically prescriptions for anticoagulants.
While most people deemed to have atrial fibrillation as an ongoing condition continued to get clot-prevention drugs, the vast majority of those whose atrial fibrillation had resolved did not, they said.
They found the proportion of patients coded as atrial fibrillation resolved with a current record of an anticoagulant prescription at the index date was just 8.3%.
Study author Dr Krish Nirantharakumar said: “Our research demonstrates that, although people with resolved atrial fibrillation continue to be at high risk of stroke, they are not getting their prevention drugs.
“Worryingly, we found that the problem seems to be becoming more common, with our research showing an increasing number of people are recorded as having atrial fibrillation as resolved and are highly unlikely to be given medication to prevent stroke,” he said.
“We cannot ever safely consider atrial fibrillation to have resolved”
Fellow study author Professor Tom Marshall added: “One possibility as to why people whose atrial fibrillation has resolved continue to be at high risk of stroke is that it had not really resolved in the first instance.
“Atrial fibrillation can be present one day and absent the next, so giving someone the all-clear may be a mistake. Another possibility is that it can come back,” he said. “Many people don’t know when they have this condition and it can come back without them or their doctor realising.
“GPs keep a register of people with atrial fibrillation, this means they are reviewed regularly and are prescribed clot-preventing drugs,” said Professor Marshall.
“But if the atrial fibrillation seems to have resolved they are taken off the register and rarely continue their treatment. It is as if they fall off the radar,” he added.
“We have shown they are still at high risk of stroke and should still be treated. We cannot ever safely consider atrial fibrillation to have resolved,” he warned.