Arrhythmias Support Group
Cardiac arrhythmia is a group of conditions in which the muscle contraction of the heart is irregular or is faster or slower than normal. Some arrhythmias are life-threatening medical emergencies that can cause cardiac arrest and sudden death. Others cause aggravating symptoms, such as an awareness of a different heart beat, or palpitation, which can be annoying.
Medications such as betablockers will decrease heart rate so the doctors will either decrease dose or take the patient off all together then they repeat ECG .
If your dad is feeling ok, no need to worry too much.