Lab-dub

Question 1

Amount of stretch on the ventricular myocardium prior to contractions

Answer 1

Preload

Question 2

Afterload

Answer 2

Arterial pressure that a ventricle must overcome whole it contracts during the ejaction

Impedance of the ventricular ejection

Question 3

Myocardiums intrinsic ability to effeciently contract and empty the ventricle

Answer 3

Contractility

Question 4

Sinus mode pacemaker membrane potential

Answer 4

-55 to -60mV

Muscle : -85 to -90mV

Question 5

Inactivated at a normal resting membrane potential

Answer 5

Fast sodium Channel

Question 6

Slow cardiac rhythm and conducting

Answer 6

Parasymphathetic STImulatio

Question 7

Stimulation of parasymphathetic nerve to the heart releases what neurotransmitter

Answer 7

Acetylcholine

Causes :
> rate of SA mode discharge decreases
> the excitability of the fibers be tweet the atrial muscle and the A-V node decreases

Question 8

What neurotransmitter is released whenever there is symphathetic stimulation

Answer 8

Norepinephrine

Question 9

The P wave is Missing due to superimposition of QRS wave

Answer 9

A- V nodal or AV bundle premature contractions

Question 10

The ectopic Foci originated from the ventricle,& the QRS Complex is often prolonged Bec the impulses must pass thru the cardiac muscle which conducts at a much lower rate than the purkinje fibers

Answer 10

Premature ventricular contractions

Question 11

Whenever the origin of the tachycardia is in the atrium but is not close to SA node,an inverted P wave appears that is caused by atrial depolarization in the direction opposite from normal.

Answer 11

Atrial paroxysmal tachycardia

Question 12

When the abnormal rhythm originated in the AV node ,p waves is obscured or inverted

Answer 12

Supraventricular tachycardia

Question 13

THIS type of tachycardia usually does not occur unless significant ischemic damage is present in the ventricles. THIS abnormality initiates lethal fibrillation.

Answer 13

Ventricular paroxysmal tachycardia

Question 14

Most serious of all cardiac arrythmias. Occurs when an impulsestimulates first one Portia n of the ventricular muscles and then Another and Finally stipulates itself. THIS stimulation causes Many Portions of the ventricle to contract at the same time whole other portions relax,therefore the impulses travel around the heart muscle.
Circus movement

Answer 14

Ventricular fibrillation

Question 15

Single large wave front travels around & around the atria.
Atria contracts 250-300 Times per minuto bec. One side of atria contracts while the other relaxes.
The strength of contractions is weak.

Answer 15

Atrial FL utter

Question 16

2 most important factors that can increase pulse pressure

Answer 16

1. Inc. SV

2. Dec. Arterial compliance