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[[Image:Rhythm_premature.png|thumb| An [[ | [[Image:Rhythm_premature.png|thumb| An [[atrial premature beat|atrial]] with a noncompensatory pause.]] | ||
[[Image:Rhythm_ventricular_premature.png|thumb|A [[ | [[Image:Rhythm_ventricular_premature.png|thumb|A [[Premature ventricular beats(PVB) / Venticular extrasystoles (VES)|ventricular extrasystole]] with a compensatory pause]] | ||
[[Image:pacemaker_rates.png|thumb|Mycoardial cells with pacemaker activity]] | [[Image:pacemaker_rates.png|thumb|Mycoardial cells with pacemaker activity]] | ||
The pacemaker cells in the sinus node are not the only cells in the heart that can depolarize spontaneously. Actually all cardiomyoctyes have this capacity. The only reason why the sinusnode 'rules' is that it is the fastest pacemaker of the heart. From sinusnode to ventricle all healthy cardiomyocytes can function as a ectopic pacemaker. Ectopic pacemaker activity can originate from the atria (60-80 bpm), AV-node (40-60 bpm) and the ventricles (20-40 bpm). So, as the sinus rate drops (e.g. during atrial infarction), other cells can take over. The configuration of ectopic beats or extrasystoles, as seen on the ECG, reveals its origin, whether they are [[ | The pacemaker cells in the sinus node are not the only cells in the heart that can depolarize spontaneously. Actually all cardiomyoctyes have this capacity. The only reason why the sinusnode 'rules' is that it is the fastest pacemaker of the heart. From sinusnode to ventricle all healthy cardiomyocytes can function as a ectopic pacemaker. Ectopic pacemaker activity can originate from the atria (60-80 bpm), AV-node (40-60 bpm) and the ventricles (20-40 bpm). So, as the sinus rate drops (e.g. during atrial infarction), other cells can take over. The configuration of ectopic beats or extrasystoles, as seen on the ECG, reveals its origin, whether they are [[atrial premature beat|atrial]], nodal or [[ves|ventrical]]. | ||
===Ectopic pacemakers=== | ===Ectopic pacemakers=== |