9- Electrical signals of the heart - the Electrocardiogram

Question 1

Site the main components of heart anatomy.

Answer 1

2 atrias
2 ventricles
Valves

Question 2

Name the different type of valves in the heart

Answer 2

Ventricles → arteries
Atria → Ventricles
Tricuspid valve (re.) 
- Mitral-, Bicuspid valve
(li.)

Question 3

Site the two mains function of the heart

Answer 3

• Blood De/Oxygenation
• Transport of nutrients, oxygen, metabolic end
  products

Question 4

What are the two aims of the cardiac pathway ?

Answer 4

1- Controlled excitation and
contraction of heart muscle
2- External modulation
according to physical
activity

Question 5

Site the conduction pathway of the heart.

Answer 5

1-Sinoartrial node
2-Atrioventricular node
3-Atrioventricular bundle
4-bundle branches
5-purkinje fibers

Question 6

What’s the name of the heart msucle ?

Answer 6

Syncytium

Question 7

What’s the aim of the plateau in the AP during cardiac electrical activity ?

Answer 7

It inhibits the reintry of calcium ions and creates a relative refractory period where an increased threshold is necessary for reactivation

Question 8

What’s the primary pacemaker in the heart ?

Answer 8

The sinoatrial node.

Question 9

When was the electrocardiogram discovered ?

Answer 9

1902

Question 10

What defines the P Wave ?

Answer 10

Depolarisation in the atria

Question 11

What is the PQ interval ?

Answer 11

Conduction from atria to ventricles - Baseline voltage: isoelectric line

Question 12

What is the QRS Complex ?

Answer 12

Rapid depolarisation of right and left

ventricles

Question 13

What is the ST interval ?

Answer 13

the Total activation of the ventricles

Question 14

What is the T Wave ?

Answer 14

Repolarisation of the ventricles,
cardiac muscle prepared for next
cycle of ECG

Question 15

What is the U wave ?

Answer 15

• Normally low amplitude, sometimes
  completely absent
• Origin unclear

Question 16

Describe the electrodes used in electrocorticogram.

Answer 16

-Stick on electrodes
-Ag/AgCl
-Single use
-Gel reduces movement
artefacts between skin
and electrode

Question 17

What are the characteristics for the lead placement for einthovens triangle ?

Answer 17

Electrodes/leads places on limbs
Frontal plane
Bipolar
I, II,III

Question 18

what are the characteristics for the lead placement in Goldberger ?

Answer 18

Unipolar
limb leads
frontal plane

Question 19

what are the characteristics for the lead placement in wilson’s method ?

Answer 19

core/chest electrodes : frontal and horizontal plane,

unipolar

Question 20

How and why is made an esophageal ECG

Answer 20

diagnostic of posterior wall of heart
unipolar
Esophageal lead

Question 21

How and why are HIS-Bundle ECG made ?

Answer 21

Intracardiac
Diagnosis of atrial, ventricular or AV nodal
arrhythmias or conduction blocks

Question 22

define Sinoatrial conduction disorders .

Answer 22

P wave can be postponed and ultimately some nbeats can be deleted

Question 23

define atrioventricular conduction disorders

Answer 23

time between p wave and qrs complex can be delayed. if it is more important, we can see p wave and the rest missing till another cycle is repeated.

Question 24

Define left Bundle branch

block

Answer 24

depol slow repol double spike

Question 25

Define right Bundle branch

block

Answer 25

fast depol, normal repol.

Question 26

what is a myocardial infarction ?

Answer 26

A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops to the coronary artery of the heart, causing damage to the heart muscle. It can happen in different areas of the heart and this has an impact on ecg.

Question 27

what are the three zones in myocardial infarction ?

Answer 27

Ischemic zone
Injury zone
Necrotic zone

Question 28

Site different devices for ecg.

Answer 28

clinical ECG sys
for chronic ECG measurement
Flexible ECG device (in dev)
Telemedicine for the future (mobile monitoring)