• Posted April 19, 2024

A-Fib Is Strong Precursor to Heart Failure

The dangerous heart rhythm disorder known as atrial fibrillation is mainly known for increasing people's risk of stroke.

But people with A-Fib actually have a much higher risk of developing heart failure than suffering a stroke, a new study shows.

In fact, the risk of heart failure associated with A-Fib is "twice as large as the lifetime risk of stroke,"concluded the research team led by Dr. Nicklas Vinter, a postdoctoral researcher with the Danish Center for Health Services Research at Aalborg University in Denmark.

Two out of five A-Fib patients (42%) will develop heart failure, compared to one in five (20%) who will suffer a stroke and one in 10 (10%) who will have a heart attack, according to results published April 17 in the BMJ.

"Although atrial fibrillation guidelines principally focus on stroke prevention, our findings indicate that heart failure was the major complication,"the researchers concluded in a journal news release.

The study also found that a growing number of people are developing A-Fib, increasing their risk of heart failure and stroke.

It used to be that one in four people would develop A-Fib at some point in their lives, researchers said.

That number has now gone up to one in three people, an increase in lifetime A-Fib risk from 25% to 31% between the 2000s and the 2010s.

A-Fib is known to increase stroke risk because the quivering, irregular heartbeat allows blood to pool and clot in the upper chambers of the heart, the American Heart Association (AHA) says.

But A-Fib can also contribute to heart failure, which occurs when the heart can't pump out enough blood to meet the body's needs, the AHA says.

A-Fib can cause the heart to beat so fast it never properly fills up with blood to pump out to the body, according to the AHA.

Nearly 16 million Americans are expected to have A-Fib by 2050, researchers said in background notes.

For the new study, they analyzed health data for 3.5 million Danish adults who started with no history of A-Fib. These folks were tracked over a 23-year period, 2000 to 2022, to see whether they wound up with the heart rhythm disorder.

More than 360,000 people wound up with A-Fib, and researchers then followed them to see if they were later diagnosed with heart failure, stroke or heart attack.

Overall, men diagnosed with A-Fib had a higher risk of heart failure than women, 44% versus 33%. Men also had a higher risk of heart attack, 12% versus 10%.

But women with A-Fib had a higher risk of stroke, 23% versus 21%.

Doctors currently focus on stroke risk following a diagnosis of A-Fib, prescribing blood thinners to prevent clotting. More than 85% of patients in Denmark diagnosed with A-Fib are prescribed these drugs, researchers said.

"Our findings encourage greater attention to secondary prevention of heart failure after atrial fibrillation,"the researchers said.

These could include encouraging patients to exercise and lose weight, developing effective therapies for A-Fib and heart failure and designing cardiac rehabilitation programs to improve heart strength, the researchers said.

More information

The American Heart Association has more about the consequences of atrial fibrillation.

SOURCE: BMJ, news release, April 17, 2024