e.g., amiodarone, beta-blockers, digoxin, disopyramide,
flecainide, mexiletine, tocainide, verapamil.
Sometimes the heart beats too fast, usually because of an abnormal
pattern of conduction across the heart, and often the best treatment is with a
drug.
The heart is its own time-keeper, and each beat is normally signalled
by one specialised portion of the heart, the natural pacemaker. Sometimes
the pacemaker or its pathways become damaged, and the heart rate is
abnormally slow, causing fainting attacks. An artificial “pacemaker” which
contains a tiny battery can be implanted beneath the skin so as to ensure that
the heart continues to beat at a satisfactory rate.