Areas of Focus

Atrial Fibrillation with Rapid Ventricular Rate (AF-RVR) 

Atrial fibrillation is the most common arrhythmia, presenting with an irregular and often rapid heart rate that may increase the risk of stroke, heart failure, and other heart-related complications. 

During atrial fibrillation, the heart’s two upper chambers, or atria, beat chaotically, irregularly, and out of coordination with the two lower chambers, or ventricles. Atrial fibrillation symptoms often include heart palpitations, shortness of breath, and weakness.

Episodes of atrial fibrillation may come and go during periods of life, or patients may have permanent atrial fibrillation. Although atrial fibrillation itself is not usually life-threatening, it is a serious medical condition. It may require emergency medical treatment and is associated with a significant increase in the risk of stroke and sudden cardiac death.


Prevalence estimates range from three to six million patients suffering from atrial fibrillation in the United States. Approximately 25 percent of these patients have paroxysmal atrial fibrillation, another 25 percent have persistent atrial fibrillation, and 50 percent have chronic or permanent atrial fibrillation.

The Current Standard of Care

There are two pharmacological approaches to managing atrial fibrillation: rate control to lower a rapid heart rate, and rhythm control to restore and maintain a regular rhythm. Unfortunately, “breakthrough” episodes—where atrial fibrillation recurs —are common regardless of which approach is used. When this happens, rate or rhythm control drugs do not provide immediate ventricular rate control due to the delayed 30 to 90-minute onset of action. Patients living with breakthrough episodes often require visits to the emergency department for urgent administration of IV calcium channel blockers or beta blockers to acutely slow their heart rate.