I was taking seloken xl 25 mg as prophylaxis for supra ventricular tachycardia. Last year in august I stopped taking it as I was abroad (tablet not available) and started taking atenol 25 mg as alternative on advice from cardiologist. But now for past one month I was getting frequent ectopic beats and now I am again taking seloken xl. Dosage increased from 25 mg to 50 mg gradually by cardiologist. I measure the retina using a mobile app and sometimes it show afib. However doctor says it needs to be documented. Dr. your advice is highly recommended.