Electrocardiogram

By H.Khorrami Ph.D.

http://khorrami1962.spaces.live.com

khorrami4@yahoo.com

CARDIAC CYCLE

Atr

ial S

ysto

le

Mitral Closes

Iso

volu

mic

co

ntr

act.

Aortic opens

S1

Rap

id E

ject

ion

Red

uce

d E

ject

ion

Iso

volu

mic

Rel

ax.

Aortic closes

Rap

id V

entr

icu

lar

Filli

ng

Mitral opens

S2

Red

uce

d V

entr

icu

lar

Fi

llin

g Atr

ial S

ysto

le

LEFT VENTRICULAR PRESSURE/VOLUME P/V LOOP

LEFT

VEN

TRIC

ULA

R P

RES

SUR

E (m

mH

g)

LEFT VENTRICULAR VOLUME (ml)

A B C

D

E F

100 150 50 0

120

40

80

PRESSURE/VOLUME RELATIONSHIPS UNDER DIFFERENT CONDITIONS

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