Page 202 - Color Atlas Of Pathophysiology (S Silbernagl Et Al, Thieme 2000)

H. Causes and Consequences of Extrasystoles

Arrival of
stimulus Anoxia, acidosis,
digitalis, etc.
Action potential in
normal myocardium

Stable
Membrane potential Spontaneous
1 decreased depolarization
Heart and Circulation e.g. Bradycardia, hypokalemia, ECG

antiarrhythmic drugs

AP,
fiber
7 Purkinje Myocardium ES
Delayed repolarization

ES

dV
dt t R

4
Early depolarizing
2 afterpotential Extrasystole

Late depolarizing
Stimulus afterpotential
Spontaneous
action potential
Myocardium

Threshold
Resting
3 potential
192

Silbernagl/Lang, Color Atlas of Pathophysiology © 2000 Thieme
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