I'm 24. Had them my entire life. Started to increase in frequency. Went to the doc had multiple holter monitors and stress tests. All is normal! I still drink coffee, and accept them as benign. Still can get freaky when I get them on the bench after an intense hockey shift.
The technical term for mine is...
AV Block: 2nd degree, Mobitz I (Wenckebach Phenomenon)
Try not to worry about them
