Hello. Thank you for your question and welcome to HCM. I understand your concern.
An established diagnosis of chronic, persistent atrial
fibrillation, mandates rate control and anticoagulation. During atrial fibrillation, the reason people have strokes, are the thrombi (clots) formed in a fibrillating, non-functional atrium. But this problem is solved with a proper anticoagulation and keeping the international standardized ratio (INR) between 2.0 - 3.0. On the other side, rate control can be achieved with various drugs that exert this effect. First, the
heart rate should be kept under 90 beats per minute. It is not the risk of strokes when the heart rate goes up, but the risk that every atrial fibrillation beat (which goes up to 400-600 beats per minute) may be transmitted to the ventricle and such a rate for the ventricle produces life threatening
ventricular arrhythmia. That is why drugs that inhibit this effect, due to their effect on the atrio-ventricular node, are used for rate control (
digoxin, most beta blockers, and
verapamil and
diltiazem from the calcium channel blockers). If these drugs do not work, there is also the class of antiarrhythmics that work with the aim of rate control in atrial fibrillation. I recommend you to discuss these options with her attending doctor.
I hope I helped with my answer. Take care.
Best regards,
Dr. Meriton