Heart 3 A Flashcards Preview

Applied Nursing 4 > Heart 3 A > Flashcards

Flashcards in Heart 3 A Deck (24)
Loading flashcards...
1
Q

Electrical conduction system of the heart composed

A
Sino atrial node
Internodal conduction tracts and interact rial conduction tracts
Atrioventricular junction
Right bundle branch
Left bundle branch
Purkinje network
2
Q

Cardiac cells

A

Myocardial cells

Pacemaker cells

3
Q

Myocardial cells function

A

Primary function contraction and relaxation

4
Q

Myocardium consist of

A

Interlacing bundles of cardiac muscles fibres arranged spirally around the circumference of the heart

5
Q

Contractility

A

Myocardial cells shorten and return to their original length when stimulated by an electrical impulse

6
Q

Conductivity

A

The ability for cardiac cells to conduct electrical impulses

7
Q

Myocardial cells are

A

Working cells of the heart

8
Q

Function of pcemaker cells

A

Generation and conduction of electrical impulses

9
Q

Pacemaker cells

A

Cannot contract

Contain more gap junctions that allows them to conduct electrical impulses rapidly

10
Q

Automacity

A

They are capable of generating impulses spontaneously

11
Q

Autonomic nervous system

A

Heart is under the constant control

12
Q

Regulation occurs

A

In medulla oblongata

13
Q

Ecg

A

Is a graphic record of the changes in magnitude and direction of electrical activity of the heart
It records depolarisation and repolarisation of the atrial and ventricular myocardial cells

14
Q

The ecg paper

A

Grid allows measurement of time in seconds ( along the horizontal axis) and voltage (amplitude) in mm along the vertical axis

15
Q

Lead placement

A

12 lead ecg lead placement

Electrodes need to be placed in the correct position to ensure accurate ECG recording

16
Q

Limb leads

A

L ( left)
R (right)
F (foot)
N (neutral)

17
Q

Chest leads

A
V1,
V2
V3
V4
V5
V6
18
Q

P wave onset and end

A

Onset is first abrupt or gradual deviation from the baseline. The end is marked were the wave flattens out to return to the baseline

19
Q

P wave direction

A

Upright in lead 11 (upright in most lead)

20
Q

P wave duration

A

Between 0.08 and .10 seconds

21
Q

P wave amplitude
Shape
P wave - qrs relationship

A

0.5 -2.5 mm
Smooth and rounded
1:1

22
Q

Pr interval
Onset and end
Pr interval - qrs relationship

A

Begins with the onset of the p wave and ends with the onset of qrs complex

  1. 12 -.20 seconds
    1: 1
23
Q
Qrs complex
Onset and end
Components 
Direction 
Duration
Amplitude 
Shape
A

At the point where the first wave of the complex just begins to deviate, abruptly or gradually from the baseline
Consist of one or more of the ff: upright deflection ( r wave) and inverted deflection (q, s waves)
May be predominantly upright, inverted or equiphasic
0.06-0.12 or 0.08 seconds
Vary from 1-15 mm in lead 11 for r and s wave. Q wave is less than 25% of the r wave
Narrow and sharply pointed

24
Q

Qt interval
Onset and end
Duration

A

The point where the first wave of the qrs complex begins to deviate

Decks in Applied Nursing 4 Class (74):