Page 193 - Color Atlas Of Pathophysiology (S Silbernagl Et Al, Thieme 2000)

C. Spread of Excitation in the Heart
II
Heart
Excited
Non AV node
excited
P PQ QRS Excitation in the
+
(mV) 0
– ECG (lead II)
of
Origin and Spread

QRS QRS ST

Plate 7.4
Sinus node

AV node T
His bundle
Bundle
branches
Purkinje fibers
Conduction Inherent
Normal sequence Time ECG velocity rate
of activation (ms) (m·s ) (min )
–1
–1
Sinus node
Impulse formation 0 P wave 0.05 60–100
Impulse arrival at right atrium 50 0.8–1.0
distant parts of atrium left atrium 85 in atrium
AV node PQ segment
Impuls arrival 50 (excitation 0.05 40–55
Impuls transmission 125 delayed)
His bundle activated 130 1.0–1.5
Distal bundle activated 145 1.0–1.5 25–40
Purkinje fibers activated 150 3.0–3.5
Subendocardial
myocardium right ventricle 175
completely activated left ventricle 190 QRS 1.0
Subepicardial right ventricle 205 complex in myo- None
myocardium left ventricle 225 cardium
completely activated 183

Silbernagl/Lang, Color Atlas of Pathophysiology © 2000 Thieme
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