4. Action Potentials = Change in membrane
potential occurring in nerve, muscle, heart and
other cells
The ECG is not an action potential but
reflects their cumulative effect at the
level of the skin where the recording
electrodes are located.
14. PARAMETROS ECG NORMAIS
P
<0,25 mV
60-100 ms
QRS
1 mm
0,1 mV S. S I. T - T
- Q
I. P -S. P - R
R
120 ms ms
360 -440
120 -20080 ms
ms
I+II+III<4mV
à O
R AÇ 1 mm (velocidade do papel: 25 mm/s)
B
LI 40 ms
CA
<120 ms
T
<0,50 mV
160 ms
15. INTERPRETAÇÃO BÁSICA DO E.C.G.
P
Calibração da <0,25 mV
voltaxe: 1cm=1mV 60-100 ms
QRS
1 mm: 40 ms
(velocidade do
papel: 25 mm/s) Frequencia: Intervalo R-R: 20 mm (0,8 s) 60 / 0,8 = 75 / min.
I+II+III<4mV
Ritmo: “sinusal normal” ? (identificar marcapaso)
S. P - R Onda P: amplitude, forma, duración
Intervalo e segmento P-R: duración
80 ms
Complexo QRS: duração, amplitude, forma <120 ms
I. P - R Segmento S-T: duração, nivel
Eixo: posição T
120 -200 ms
<0,50 mV
I. Q - T S. S - T
360 -440 ms 120 ms 160 ms
16.
17. PARAMETROS ECG NORMAIS
P
<0,25 mV
60-100 ms
QRS
1 mm
0,1 mV S. S I. T - T
- Q
I. P -S. P - R
R
120 ms ms
360 -440
120 -20080 ms
ms
<4mV
à O
R AÇ 1 mm (velocidade do papel: 25 mm/s)
B
LI 40 ms
CA
<120 ms
T
<0,50 mV
160 ms
18. INTERPRETAÇÃO BÁSICA DO E.C.G.
P
Calibração da <0,25 mV
voltagem: 60-100 ms
1cm=1mV
QRS
1 mm: 40 ms
(velocidade do
papel: 25 mm/s) Frequencia: Intervalo R-R: 20 mm (0,8 s) 60 / 0,8 = 75 / min.
Ritmo: “sinusal normal” ? (identificar marcapaso)
I<4mV
S. P - R Onda P: amplitude, forma, duración
Intervalo e segmento P-R: duração
80 ms
Complexo QRS: duração, amplitude, forma <120 ms
I. P - R Segmento S-T: duração, nivel
Eixo: posição T
120 -200 ms
<0,50 mV
I. Q - T S. S - T
360 -440 ms 120 ms 160 ms
35. Be g inning to
Re c o g nize Rhythms
Step 1: Are there P waves?
Step 2: Are there QRS complexes?
Step 3: Are the P waves and QRS
complexes related?
41. Example 1 Continued
STEP 3
• Are they related, 1:1?
Yes, there is one P wave for every QRS.
This is called a sinus rhythm
42. Example 2
Follow steps 1-3 as demonstrated in Ex. 1.
This is also a sinus rhythm.
43. Example Three
Following the same steps, this one
doesn’t match up!?!?
44. Example 3 continued
Step 1
• Are there P waves?
Yes,
• Note: notice the dotted arrows indicate the
location of P waves buried in the stronger
electrical activity of the QRS complexes.
45. Example 3 Continued
STEP 2
• Are there QRS complexes?
Yes, there are normal, narrow
QRS complexes.
46. Example 3 Continued
STEP 3.
• Are they related?
NO, they are both regular in shape and
rate, but there is no relation between
them.
• This shows a Complete Heart Block, also called
a 3rd degree block.
• Can the Heart effectively pump blood if the
Atria and Ventricles are not working together?