A study published in the European Heart Journal says the heart drug digoxin, a treatment for the common irregular heart rhythm disorder known as atrial fibrillation, has been tied to a 41 percent increase in death. But researchers say the deaths my not entirely be the fault of digoxin.
The study, conducted by researchers at the University of Kentucky, involved 4,060 atrial fibrillation patients. Half were prescribed digoxin while others were given different heart medications or treatments. During the course of the study 666 patients died and 375 of them had been on digoxin at their last follow-up visit.
Researchers took into account conditions such as general health and other medications taken. They found that digoxin was also independently linked with a 41 percent increase in deaths from any cause, a 31 percent increase in deaths from cardiovascular causes, and 61 percent increase in deaths from irregular heart rhythm or arrhythmia other than atrial fibrillation. Researchers say that while digoxin appears to be a culprit in the deaths, it may not be entirely to blame. Other factors may be involved.
During atrial fibrillation, the heart’s two upper chamber (the atria) beat chaotically and irregularly – out of coordination with the lower two chambers (the ventricles) of the heart. This can cause the blood to pool in the chambers of the heart, which can create blood clots. If these blood clots break loose and travel to the brain, they can cause a stroke. Atrial fibrillation patients are up to seven times more like to suffer a stroke than patients without the heart condition.
Atrial fibrillation may be treated with medications, like digoxin, to either slow the heart rate to a normal range or revert it back to normal. Synchronized electrical cardioversion can be used to convert atrial fibrillation to a normal heart rhythm. Surgical and catheter-based therapies may also be used to prevent recurrence in certain individuals.
Often patients with the heart condition take blood thinners to protect them against stroke. However, blood thinners can increase the risk for major bleeding events. Warfarin has long been the anticoagulant used for atrial fibrillation patients, but in 2010, the Food and Drug Administration (FDA) approved Pradaxa, a new type of blood thinner for the same indication.
Pradaxa quickly became a blockbuster medication, bringing in more than $1 billion in revenues in just one year. However, in the first 14 months of its approval, Pradaxa was linked to more than 900 gastrointestinal bleeds and more than 500 bleeding deaths.