Cardiac

Question 1

Action potentials with plateau phases

Answer 1

Found in atrial and ventricular muscle cells

Question 2

Biphasic action potentials

Answer 2

Arising in the SA and AV node

Question 3

Inotropy

Answer 3

CA impacting squeeze of the heart

Question 4

Chronotropy

Answer 4

HR

Question 5

Dromotropy

Answer 5

Speed to the AP down the pathway

Question 6

Lusitropy

Answer 6

Relaxation of the heart (diastolic heart failure)

Question 7

Cardiac conduction pathway

Answer 7

1. Sa node
2. Intermodal tracts (controversial)
3. AV node
4. AV bundle of HIS
5. Bundle branches
6. Purkinje fibers
7. Ventricular muscle

Question 8

Spontaneous depolarization

Answer 8

1. Potassium efflux progressively slowing
2. Sodium influx progressively increasing
3. Calcium influx

Question 9

Resting membrane potential of ventricular cell

Answer 9

All striated muscle

-90 mV

Question 10

Resting membrane potential of SA node

Answer 10

-70 mV

Question 11

SA node rate with no influences

Answer 11

108-115

Question 12

Calcium influence of K channel

Answer 12

Hypocalcemia- duration of plateau is prolonged

Hypercalcemia- duration of plateau is shortened

Question 13

PR interval

Answer 13

Beginning of P wave to beginning of QRS

Normal 0.12-0.2 seconds

Question 14

QRS interval

Answer 14

Normally 0.12 or less

Question 15

HR method

Answer 15

From R-R

1. Divide 1500 by number of mm between 2 consecutive R waves
2. Count R waves occurring in 6 seconds and multiply by 10

Question 16

Each mm on EKG strip

Answer 16

40 ms (0.04 seconds)

Question 17

1st degree heart block

Answer 17

PR greater than 0.2 and is constant

Question 18

2nd degree AV block type 1

Answer 18

Wenckebach
Mobitz I
Progressive PR increase until QRS beat is dropped
Progressive shortening of R-R

Question 19

2nd degree AV block

Answer 19

Mobitz II
Sudden appearance of nonconducted P wave
PR and RR intervals constant

Question 20

3rd Degree heart block

Answer 20

Complete heart block
Independent atrial and ventricular activity
No relationship between P and QRS

Question 21

Bain bridge reflex

Answer 21

Increase in HR during inspiration due to right atrium stretch
Thoracic pressure falls—>inferior vena cava widens—>venous BP falls—>increased venous return to RA—>right atrium stretch

Question 22

Subendocradial ischemia and injury

Answer 22

ST segment depression greater than 1mm

Question 23

Transmural ischemia

Answer 23

Inverted T waves

ST segments elevation greater than 1 mm

Question 24

QRS complex

Answer 24

Comes from ventricular depolarization (phase 0)

Question 25

T wave

Answer 25

Comes from ventricular repolarization (phase 3)

Question 26

QT interval

Answer 26

From duration of plateau phase (phase 2) Shortened=hypercalcemia Prolonged=hypocalcemia

Question 27

U waves

Answer 27

Come from hypokalemia

Question 28

Wolff Parkinson’s white syndrome

Answer 28

Less than 100 beats/min Accessory track called bundle of Kent P wave normal, short PR interval, delta wave leading into QRS Avoid dig and verapamil- increases conduction through accessory tract

Question 29

V1-V2

Answer 29

Posterior | Left circumflex

Question 30

II, III, aVF

Answer 30

Inferior wall | RCA

Question 31

I, aVL, V1-4

Answer 31

Septum, anterior wall | LAD

Question 32

I, aVL, V5-6

Answer 32

Lateral wall | Left circumflex

Question 33

Best lads for ST segment depression or elevation

Answer 33

V3-5, III, aVF

Question 34

Lead for assessment of narrow QRS rhythms

Answer 34

Lead II

Question 35

Ohms law

Answer 35

Q=change P/R Q= flow rate P=pressure R=resistance

Question 36

MAP

Answer 36

[(CO x SVR)/80] + CVP

Question 37

SV

Answer 37

EDV-ESV CO/HR 60-90mL

Question 38

EF

Answer 38

SV/EDV (EDV-ESV)/EDV

Question 39

Adrenal gland pneumonic

Answer 39

GFR—> ACT Glomerulosa—>Aldosterone (salt) Fasciculaa—>Mineralacorticoids (sugar) Reticularis—> Androgen (testosterone) (sex)

Question 40

CO

Answer 40

HR x SV

Question 41

Stroke volume determined by interplay

Answer 41

Preload Afterload Contractility

Question 42

Preload determined by

Answer 42

Intravascular volume Venous tone Ventricular compliance

Question 43

Atrial kick % of contraction

Answer 43

25-30%

Question 44

SI

Answer 44

SV/BSA | 40-60 mL/m2

Question 45

SVR

Answer 45

(80)(MAP-CVP)/CO | 900-1500 dynes.sec.cm-5

Question 46

PVR

Answer 46

(80)(PAP-PCWP)/CO | 50-150 dynes.sec.cm-5