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Flashcards in 1 Electrical Activity Of The Heart Deck (17)
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1
Q

Which side of the heart is involved in pulmonary circulation?

How many chambers?

A

RIGHT

Left is SYSTEMIC

4 2 atria and 2 ventricles

2
Q

What are the names of the two atrioventricular valves and which side are they on?

What about the 2 semilunar valves?

A

Bicuspid (mitral)- LEFT
Tricuspid- RIGHT

Aortic valve-LEFT
Pulmonary valve- RIGHT

3
Q

What’s a period of contraction, force generation, and blood expulsion?

What’s a period of relaxation, filling with blood, readying for next systole?

A

Systole

Diastole

4
Q

(TP) Left atrial fibrillation (improper excitation and contraction) would most greatly affect filling of which other heart chamber?

A. Left ventricle
B. Right ventricle
C. Right atrial
D. Left atria

A

Left ventricle

5
Q

The ___ node is the pacemaker of the heart because it’s the fastest. Fires while others are still slowly depolarizing

A

SA

6
Q

The _______ pacemaker can override SA node if:

__ node slows

_______ is faster

Pathology introduces a conduction block

A

Ectopic

SA

Ectopic

7
Q

List the steps of flow for depolarization

A

SA node fires

Atria depolarize (right first from base to apex)

Septum and inner ventricular muscle

Ventricles (all at once)

Coordination allows for maximal blood ejection

8
Q

Heart rate is modulated by altering the __ node firing rate. Altering conduction through the __ node as well.

A

SA

AV

9
Q

Sympathetic control of the SA node is positive _______ stimulation that ______ HR.

Has _1 receptors. Increases funny current and Ca current

A

Chronotrope. INCREASE

B1

10
Q

Parasympathetic autonomic control of SA node is a _______ chronotrope which _______ HR.

_2 receptors.
______ Ca current and funny current

______ K current

A

Negative. Decreases

M2
Decreases
Increases

11
Q

The sympathetic autonomic control of the AV node is a _______ dromotrope that _______ conduction velocity.

B1 receptors
______ Ca current during upstroke
______ ERP

A

Positive. Increases

Increases
Shortens

12
Q

Parasympathetic control of AV node is a ________ dromotrope that _______ conduction velocity.

M2 receptors
_______ Ca current during upstroke
______ K current to hyperpolarize
_______ ERP

A

Negative. Reduces

Decreases
Increases
Lengthens

13
Q

What is the time from initiation of atrial depolarization to initiation of ventricular depolarization? Usually between .12-.2 seconds

A

PR interval

14
Q

What’s the time from first ventricular depolarization to last?

A

QT interval

15
Q

What’s the time from last depolarization to initiation of repolarization?

A

ST segment

16
Q

What effect would increasing parasympathetic tone have on the ECG?

A. Increase the PR interval
B. Increase the ST segment
C. Increase the QT Interval
D. Shorten the P wave

A

A. Increase the PR interval

17
Q

(TP) What effect would a sodium channel (NaV) blocker have on the ECG?

A. Decrease the PR interval
B. Increase the T wave
C. Increase the QT Interval
D. Shorten the P wave

A

C. Increase the QT interval