An international consortium of cardiologists is mounting a new push for governments to introduce national screening programs for atrial fibrillation in a bid to cut stroke and stroke-related death rates worldwide.
The move comes as the international collaboration, AF-Screen, including cardiologists, neurologists, GPs, health economists, nurses, pharmacists and patient support organisations from 33 countries, released its final recommendations following a lengthy review of the evidence carried out over two years.
In Australia, the benefits of such a program would be significant argues Professor of Cardiology at Concord Hospital and AF-Screen co-founder, Ben Freedman.
“If we managed to screen 75% of people aged over 65 and got 80% with AF on to medication, we’d prevent more than 250 strokes every year … Imagine seeing that the world over. Such a simple action to see so many lives spared from stroke.”
The white paper just published in Circulation calls for governments worldwide to introduce one-off screening for all older people, at age 65 or possibly older.
The group recommends running programs through GPs, pharmacies or in the community. Detection could be carried out with pulse checking, a blood pressure monitor or, ideally, a handheld ECG device, which they say offers a firm and rapid AF diagnosis and has the advantage of providing a verifiable ECG trace that guidelines require for diagnosis.
Repeated handheld ECG recordings taken with these devices have the diagnostic accuracy equivalent to standard event recorders, superior to 12-lead ECG and 24-hour Holter for paroxysmal AF successfully in large-scale AF screening studies, the group claims.
While it concedes that single-lead ECGs may not always show P-waves, the group argues that the advantages of a routine screening program using these devices outweigh the limitations.
AF-Screen has also called for doctors to adopt a default position of prescribing anticoagulants to all patients with asymptomatic AF unless they are identified as low risk.
Writing in the paper, Professor Freedman argues that screen-detected AF, found at a single time point or by twice-daily ECG recordings over 2 weeks in higher risk people, is not a benign condition.
Combined with additional stroke factors, asymptomatic AF carries enough risk of stroke to justify anticoagulation.
But Director of National Heart Foundation, Professor Garry Jennings said the evidence about who to screen and at which time points remains unclear.
“Nobody questions that AF is an important cause of stroke – and probably more stroke than we previously realised – but screening is not something to be embarked upon lightly.
Unless you’ve got the right systems in place to make sure that the right things happen when something is picked up then you can actually do harm,” he told the limbic referring to one particular recommendation in the white paper, which said there is already a “strong case” for implementing AF screening now while large randomised outcomes studies could run alongside the program to “strengthen the evidence base.”
He also said that the single time-point screen would likely miss a lot of people at risk of AF.
“Clearly we need much better ways of assessing risk of stroke beyond the ECG to know how to target a screening program to get a better pick up rate. We need bigger and better studies looking at how we can refine our approach to picking up AF before we introduce a screening a program.”
In the meantime Professor Jennings said there could be a role for opportunistic screening.
“The case for opportunistic screening is strengthening. The evidence is that people with asymptomatic AF who are picked up opportunistically are just as likely to have a stroke as people who present with clinical symptoms.
“The fact is, we screen for much less likely conditions, prostate cancer for example, with tests that have much less predictive value than an ECG for AF.”