Clinical 1 Flashcards
1
Q
P wave
A
- atrial depolarization (of both atria)
- upright: 1, 2, V4-6, AVF
- inverted: AVR
- variable: 3, AVL, other chest leads
2
Q
Why does the depolarization go slowly through the AV Node?
A
slow moving Ca2+ ion
3
Q
P-R Interval
A
- beginning of P wave to beginning of QRS complex
- time for SA Node to ventricular muscle fiber (.12-.2 seconds–>3-5 small squares wide)
4
Q
QRS Complex
A
- ventricular depolarization (.05-.1 seconds)
- should NOT be more than .-3 seconds
5
Q
Q Wave
A
- narrow/small
- 1-2mm is normal in 1, AVL, AVF, V5-6
6
Q
What do Purkinje fibers use for fast moving conduction?
A
Na+ ions
7
Q
ST segment
A
- segment between S and T waves
- normally isoelectric
- normally elevated NOT more than 1mm in standard leads, and 2mm in chest leads
- normally NEVER depressed more than .5mm
8
Q
T wave
A
- ventricular repolarization
- upright: 1, 2, V3-6
- inverted: AVR
- variable: 3, AVL, AVF, V1-2
- shape: slightly rounded, asymmetrical
- heigh: no greater than 5mm in standard leads, and 10mm in precordial leads
9
Q
Precordial leads
A
aka chest leads
10
Q
QT Interval duration is…
A
- length of ventricular systole
- changes can be indicative of MI, myocardial injury, and myocardial ischemia
11
Q
A T wave ischemic pattern is associated with…
A
inverted T waves
12
Q
Causes of a prolonged PR interval
A
- In AV block due to coronary disease, RA…
- Hyperthyroidism
- Normal variation
13
Q
Causes of shortened PR interval
A
- AV junctional and low atrial rhythms
- Wolff-Parkinson White Syndrome
- Low-Gangong Levine Syndrome
- Glycogen storage disease
- Hypertension
- Normal Variant
14
Q
Deflection vs. Amplitude
A
- direction
2. magnitude
15
Q
AVF is a combination of what two leads?
A
II and III
