PTE 744 Heart Sounds & EKG's

what occurs during systole?

ventricular contraction

what valves are OPEN during systole?

semilunar

aortic and pulmonary

what valves are CLOSED during systole?

AV

bicuspid and tricuspid

what occurs during diastole?

ventricular relaxation

what valves are OPEN during diastole?

AV

bicuspid and tricuspid

what valves are CLOSED during diastole?

semilunar

aortic and pulmonic

what is heart valve stenosis?

narrowing of the diameter of valve

what does a heat valve stenosis sound like?

louder, harsher, longer

what is heart valve regurgitation?

something block valve from fully closing

causing a backward movement of blood

what does a heart valve regurgitation sound like?

softer, longer

what heart sounds are normal?

S1 and S2

what sounds do S1 and S2 make?

S1: Lub

S2: Dub

when is S3 normal?

children, pregnancy, high level athletes

when do you heart S3?

early diastole

Lub Dub Dub

Is S4 heart sound ever normal?

no, always abnormal

what does S4 heart sound like? why does it occur?

Ta Lub Dub

decreased compliance of ventricles

How is a normal heart sound described?

short and soft

how is a stenotic heart sound described?

loud, long, harsh

When does a stenotic heart sound occur?

Sound is created when the valve is OPEN

If a pulmonic valve has stenosis, when will you hear the sound?

S1 / Systole

Semilunar valves are open

If a bicuspid valve has stenosis, when will you hear the sound?

S2 / Diastole

AV valves are open

how is a regurgitation heart sound described?

soft and longer

when does a regurgitation heart sound occur?

when the valves are closed

how is a ductus arteriosus heart sound decribed?

continuous through S1 and S2

Heart Sound Example:
a louder, longer first heart sound is present, then followed by a short, soft second sound. what condition is present

S1: abnormal → stenosis → SL Open

S2: normal

Aortic or pulmonic stenosis present

Heart Sound Example:

A short and soft first heart sound is present, then followed by a longer, softer heart sound. What condition is present

S1: Normal

S2: Abnormal → Regurgitation → SL Closed

Aortic or pulmonic regurgitation

Heart Sound Example:

A longer, softer first heart sound is present, then followed by a short and soft second heart sound. What condition is present?

S1: Abnormal → regurgitation → AV closed

S2: Normal

Bicuspid or tricuspid regurgitation

what rate does the SA node keep the heart pumping at?

60-100 bpm

what rate will the AV node keep the heart pumping at if the SA node is damaged?

40-60 bpm

what rate will the heart pump at if the SA and AV nodes are damages and via what mechanism?

<40 bpm

ventricular pacemaker rate AKA Hail Mary

Give an example of a mechanism that could “knock out” or inhibit the SA node from firing?

dilation or stretching of the right atrium

SA node is a nerve, and nerves do not like to be stretched or compressed!

an electrocardiography (ECG or EKG) assess what?

the electrical conductivity of the heart

what is a limitation to an ECG or EKG?

it only assess what is going on in the moment the test is ran, it does not predict future events

What is happening during the P wave

Atrial depolarization (contraction)

what occurs during the PR segment

slows down to get last of atrial blood into ventricle

allows for more ventricular filling and stretch for optimal contraction

what occurs during the PR interval?

combination of P wave and PR segment

“atrial kick” occurs

increased ventricular filling

how does the “atrial kick” during the PR interval affect ventricular output?

increased it by 20%

allowing for maximal filling and pre-stretch to ventricle for optimal contraction

what occurs during the QRS complex?

systole → ventricular depolarization (contraction)

Atrial repolarization

why cannot you not see atrial repolarization on a ECG or EKG?

it is hidden in the QRS complex due to the significant electrical activity caused by ventricular depolarization

What occurs during the ST segment?

happening after ventricular depolarization but before repolarization

relaxation?

what occurs during the T wave

Ventricular repolarization

What occurs during the QT interval?

total time ventricles are electrically active between depolarization and repolarization

what is the time duration for a small square on a EKG paper?

0.04 seconds

what is the time duration for a big square on a EKG paper?

0.20 seconds

how long is a normal time duration for a PR interval

0.12 - 0.2 seconds

within one big box

how long is a normal time duration for a QRS complex?

0.08 - 0.10 seconds

2-3 small boxes

what is the normal time duration for a QT interval?

less than 0.45 seconds

less than 2 big boxes

What is the R-R interval

Space between “R” point to “R” point

R point = peak of QRS complex

What does R-R interval Assess?

Heart Rhythm and Rate using EKG strip

how do you assess R-R interval using a note card?

Ensure even spacing between R points

When assessing R-R interval, what is considered regular?

may very 2-3 small boxes

breathing during test will cause slight variation

When assessing R-R interval, what is considered irregular?

more than 3 small boxes is consdiered irregular heart rate

Describe how to calculate heart rate using the 6 second strip method

Count R points and multiply by 10 for estimated HR

Can you assume all strips are 6 seconds?

NO BAD BAD BAD

it must specifically say 6 second strip

what is the “counting backwards” method to estimate HR?

Count number of big boxes in R-R interval then count backward using assigned numerical order for each box

what is the “counting backward” numerical order you have to follow exactly?

300, 150, 100, 75, 60, 50

describe the counting large boxes method for HR estimation

Count how many big boxes are in an R-R interval

then divide 300 by number of big boxes

describe the counting small boxes method for HR estimation

count how many small boxes are in a R-R interval

then divid 1500 by number of small boxes

when analyzing a EKG strip, what are the main/big categories you check?

P waves

QRS complexs

T wave

PR interval

R-R interval

when anazlying a EKG strip’s P waves, what are you looking for?

Present

symmetrical

upright

single p wave before every QRS complex

when analyzing a EKG strip’s QRS complexes, what are you looking for?

present

time duration: 0.08 - 0.10 (<2.5 small boxes)

when analyzing a EKG strip’s T wave, what are you looking for?

Present

symmetrical

upright

when analyzing a EKG strip’s PR interval, what are you looking for?

interval time duration: 0.12 - 0.20 (3-5 small boxes)

when analyzing a EKG strip’s R-R interval, what are you looking for?

if its regular or irregular

determine using note card

If the QRS complex is more than 2.5 small boxes, what does that potentially mean?

bundle branch block

what is a normal rhythem called?

Sinus Rhythm

What is a rhythm called that has less than 60 bpm?

Sinus Bradycardia

what is a rhythem called that has more than 100 bpm?

sinus tachycardia

Define Ectopic Focus

a singular area of tissue in the heart that will randomly fire outside of normal conduction system

its trying to preserve contraction

Define Ectopic Foci

Multiple area’s of tissue in the heart that will randomly fire outside of normal conduction system

its trying to preserve contraction

When you see Multiple P-waves before QRS complexes, what rhythm is it?

Artrial Flutter

looks like saw blade

Ectopic Focus or Foci: Atrial Flutter

Ectopic Focus

When you see no P-waves before a QRS complex, what rhythm is it?

Atrial fibrillation

chicken scratch

Ectopic Focus or Foci: Atrial Fibrillaiton

Ectopic Foci

what did Dr Himes call atrial fibrillation that caused a frenzy?

irregularly irregular rate

What are patients at a higher risk for during Atrial Fibrillations?

blood clots due to the muscles “quaking”

When you see inconsistent QRS complex durations, what rhythm is that?

Pre-mature Ventricular Contractions (PVC’s)

wide and bizarre QRS complexes

>0.10 time duration

What causes PVC’s?

irritation coming from outside the conduction system

what is the result of a PVC?

lower cardiac output

When are PVC’s no concerning? when are they concerning?

Not concerning: Occasional, not consistent

Concerning: the more they occur, the more concerning, decrease in CO every time they occur

what can cause an occasional PVC?

Caffeine

What are PVC’s called when they look the same on a EKG strip?

Unifocal PVC

What is it called when you have PVC’s, but they all look different?

Multifocal PVC

What is it called when every other beat is a PVC?

Bigeminy

What is trigeminy rhythm?

normal QRS, normal QRS, PVC, repeat

What does it mean when you see a upside down QRS complex?

heart damage

bad bad bad

What can cause Ventricular Tachycardia?

3-4 PVCs in a row that all look the same

unifocal PVCs

Ectopic Focus or Foci: Ventricular tachycardia?

Ectopic foci ventricles

what makes Torsades de pointes different from tachycardia?

undulating waveform from 1 big box to 3 big boxes

amplitude of waveforms are all inconsistent

what does Ventricular fibrillation look like

inconsistent QRS complex, shape and form

what does ventricular fibrillation lead to?

asystole or flat line

what is this heart rhythm?

Atrial Flutter

mutiple P waves

saw blade

what is this heart rhythm?

Atrial Fibrillation

no P waves

chicken scratch

what is this heart rhythm?

pre-mature ventricular contraction PVC

what is this heart rhythm?

Pre-mature ventricular contraction - Bigeminy

what is this heart rhythm?

pre mature ventricular contraction - Trigeminy

what is this heart rhythm?

ventricular tachycardia

what is this heart rhythm?

Ventricular tachycardia

Torsades de pointes

What is this heart rhythm?

Ventricular fibrillation