Complex sentence: Today, the most common indications for digoxin are atrial fibrillation and atrial flutter with rapid ventricular response, though beta blockers and/or calcium channel blockers are a better first choice.
Split into simpler sentences: Today, the most common indications for digoxin are atrial fibrillation and atrial flutter with rapid ventricular response. Beta blockers and/or calcium channel blockers should be the first choice.