deCODE AF™

A DNA-based test enabling stroke prevention through more effective screening for atrial fibrillation. Targets outpatient Holter monitoring towards those stroke patients most likely to have intermittent AF. Treating AF patients with warfarin reduces their risk of stroke by 70%.

Screening and prevention

How deCODE AF™ can help.

Diagnosing a larger proportion of AF

Between 15 and 20 percent of all strokes are cardiogenic, the subtype with the highest morbidity and mortality. Atrial fibrillation is the leading cause of cardiogenic stroke, but because it is often intermittent it is under diagnosed and undertreated in those who receive only in-patient cardiac monitoring following a stroke.

Targeted screening

Monitoring all ischemic stroke patients in an ambulatory setting may be considered impractical or too expensive. deCODE AF™ addresses this problem by identifying those stroke patients who are more likely to have AF. These patients may therefore benefit most from outpatient cardiac monitoring.

Better prevention

Two studies have shown that an extra week of ambulatory cardiac monitoring using an automated digital event recorder following a stroke may identify AF in another 5.6-14.3% of stroke survivors. For those in whom AF is detected, treatment with warfarin can reduce the risk of a secondary AF-related stroke by 70%.

AF is the leading cause of cardiogenic stroke.

Between 15-20% of all strokes are cardiogenic, the subtype with the highest morbidity and mortality

By providing information on an individual’s risk of having AF, deCODE AF™ may enable doctors to identify those patients who may benefit from outpatient cardiac monitoring for AF after a negative post-stoke in-hospital work-up . Published research and best clinical practice suggest that individuals with a history of stroke or with other risk factors, can significantly reduce their risk of stroke through treatment with the anticoagulant drug, warfarin.

Some stroke patients have intermittent AF and may no longer be in AF when they arrive at an emergency room. Many of these may not be diagnosed during the standard 24 to 48 hours of inpatient cardiac monitoring. As a result, these patients may be placed on an antiplatelet agent rather than much more effective warfarin treatment for secondary prevention of AF-related stroke.

More extensive outpatient cardiac monitoring is not routinely done due to the expense involved. deCODE AF™ offers a novel means of meeting this challenge – of identifying those who may benefit from outpatient cardiac monitoring after leaving the hospital, and thereby detecting a greater proportion of AF cases .

With the widespread current use of statins, the incidence of myocardial infarction is slowly decreasing. By contrast, the rate of stroke is increasing as a higher proportion of the population survives to the age of higher risk of stroke. It is also clear that statins have only about half the effect on stroke prevention as they do on MI prevention. Part of this may be because much of AF is not related to atherosclerosis. Therefore, we may expect the proportion of stroke due to diagnosed and undiagnosed AF to continue to increase as the atherosclerosis-related strokes are decreased by statins and anti-platelet agents. In order to effectively address AF-related strokes, a test such as deCODE AF™ may improve AF detection which can enable physicians to personalize the treatment of those with AF, delivering the benefits of warfarin to those who need it.

A test such as deCODE AF™ may improve AF detection and assist physicians in personalizing the treatment of those with AF, delivering the preventive benefits of warfarin to those who need it. It has been shown that treatment with warfarin can reduce the risk of stroke in those with AF by about 70%⁽¹⁾. In fact, ACC and AHA guidelines recommend lifelong treatment for AF patients with at least one additional risk factor for stroke including history of stroke or TIA⁽²⁾. However, because AF may be intermittent rather than continuous and because patients are often asymptomatic during the arrhythmia, it may go undiagnosed even following a stroke or transient ischemic attack (TIA).

By detecting a greater proportion of AF cases, i.e. especially those who have intermittent AF, deCODE AF™ may help prevent recurrent strokes. Warfarin treatment of these cases with decrease of future costs of morbidity and mortality may more than outweigh the extra cost of testing and monitoring

Because deCODE believes this test is useful for informing, monitoring and treatment strategies for those who have suffered either ischemic stroke or transient ischemic attack, we recommend that physicians familiarize themselves with the impact the test can have. They should share this information with their patients, explaining to them what atrial fibrillation is and why the information yielded by the risk test may, together with analysis of other risk factors, be useful for providing the best possible prevention strategy for future stroke.

This content was last reviewed on March 16, 2011.