I have been diagnosed with an Incomplete Right Bundle Branch Block but I am frequently having around 30 mins to an hour of irregular heart beats. It slows down, skips a beat, goes faster then repeats. I have had an echo done which was normal, bloods were normal and ecg was borderline. The first ECG showed an abnormal sinus rhythm however, the last 2 have only showed up as IRBBB with a normal sinus rhythm. Can anyone give me a reason as to what the problem could be. I have no stress or anxiety.