I believe I am having SVT since I saw my doctor yesterday and he did an EKG and said Im having an extra heartbeat about every third beat.  I recently took Red Yeast Rice for high cholesterol (Im 50 y.o.) and think this may be a side effect.  Even though my last dose of the herb was over 24 hours ago Im still having the irregular heart beat.  Is this something that I should be concerned about?
Hello, You need to be concerned about it and see the treatment for this. This is likely an atrial fibrillation, in which heart rate can suddenly go up leading to dizziness, fainting or syncope, shortness of breath. Also, it may increase the risk is clot formation in atrium which may be harmful. You will certainly test to evaluate it. In treatment, you'll need medicine to keep heart rate under control and blood thinners. So get back if you have any doubts and if any reports like are available for detailed analysis.