8/3- How to Msr Cardiac Fct at the Bedside Flashcards Preview

_MS2 Cardio > 8/3- How to Msr Cardiac Fct at the Bedside > Flashcards

Flashcards in 8/3- How to Msr Cardiac Fct at the Bedside Deck (41):
1

Pulmonary artery pressure? (mmHg)

15-30/3-12

2

Right ventricular pressure? (mmHg)

15-30/0-8

3

Aortic pressure? (mmHg)

100-140/60-90

4

Left ventricular pressure? (mmHg)

100-140/5-12

5

Pulmonary capillary wedge pressure? (mmHg)

5-`1

6

The right atrial pressure waveform has:

- _(#)_ positive waves (examples)

- _(#)_ negative deflations (examples)

Three positive waves:

- a wave: atrial systole (follows ECG "P" wave)

- c wave: TV closure

- v wave: atrial filling (followed by TV opening)

Two negative deflations:

- x-descent: atrial relaxation

- y-descent: rapid atrial emptying

7

Right ventricular pressure has:

- ______ peak pressure

- ______ pressure phases (examples)

Systolic Peak Pressure

Diastolic Pressure Phases

- Rapid filling phase

- Slow filling phase

- Atrial contraction

8

What is this? Label?

Q image thumb

a wave- atrial kick

c wave- closure of AV valve

x descent- atrial relaxation

v wave- atrial filling from jugular vein (peaks when AV valve closes)

y descent- rapid early emptying of atrium (atrial counterpart of rapid early filling phase of ventricle) Which descent(s) is/are clinically useful?

**Change in y descent is very important sign of abnormality!! Critical!

** x descent abnormality (steeper/shallower) has no specificity for cardiac disease

A image thumb
9

Measurements of systolic function (4)?

- Hemodynamic measurements (4)

- Regional ventricular function

- Left ventricular mass

- Ventricular response to stress

10

What are hemodynamic measurements of cardiac function?

- Ventricular volume

- Ejection fraction

- Cardiac output

- Vascular resistance

11

How do we measure ventricular volumes?

Systolic and diastolic volumes can be measured by echocardiography or angiography (nuclear or contrast dye)

12

What is typical LV end-diastolic volume?

(don't need to memorize)

79 +/- 11 mL/m2

13

What is typical LV end-systolic volume?

(don't need to memorize)

28 +/- 6 mL/m2

14

Equation for stroke volume?

EDV - ESV

(Typically LV: 79 - 28 ~ 51 mL/m2)

15

What is left ventricular ejection fraction?

What does it indicate?

What increases/decreases it?

Ratio of stroke volume to end-diastolic volume: SV/EDV

- Measure of cardiac performance

- Increases with increase in preload and contractility or decrease in afterload

16

What is normal LVEF?

67 +/- 7% (> 50%)

17

What is cardiac output?

Blood flow to systemic circulation in every minute

CO = SV x HR

(SV: blood ejected per beat)

18

What is cardiac index?

Cardiac output/body surface area

CI = CO/BSA

19

How can we measure CO? (2 main methods)

Which is used more often?

- Thermodilution method using a Swan Ganz catheter** more common

- Doppler echocardiography (complicated)

20

Method behind measuring CO by Swan Ganz catheterization?

Thermodilution method using a Swan Ganz catheter:

- Balloon-tipped catheter floated into the pulmonary artery from a systemic vein

- 10 mL saline injected into the RA and resultant change in PA blood temperature (detected by a thermal sensor) is used to compute the cardiac output

- Then we infer left side CO from right side (they are equal!!!) 

A image thumb
21

T/F: Left sided cardiac output can be estimated from the right side (via Swan Ganz catheterization)?

True

Right side cardiac output approximates the left

22

What can we measure by Swan Ganz catheterization?

- Cardiac output

- Pulmonary capillary wedge pressure

As the balloon is occluded, the P measured at the catheter tip is the pulmonary cap wedge P which reflects the left atrial pressure transmitted through the pulmonary circulation into the pulmonary caps

23

What is vascular resistance? Types?

Ratio of pressure gradient to blood flow

- Systemic vascular resistance

- Pulmonary vascular resistance

24

Equations for:

- Systemic vascular resistance

- Pulmonary vascular resistance

Relative relationship?

Systemic vascular resistance: SVR = (AO-RA)/CO Pulmonary vascular resistance: PVR = (PA-LA)/CO

SVR is ~10x higher than PVR

25

What is regional ventricular function?

Extent of myocardial thickening and wall motion of various myocardial segments

26

How is regional ventricular function measured?

- Echocardiography

- Radionuclide angiography

- Cardiac catheterization with contrast dye angiography

27

How may wall motion be described?

- Normal

- Hypokinetic

- Akinetic

- Dyskinetic

28

How is left ventricular mass most commonly measured?

Echocardiography

29

What can increase LVM (left ventricular mass)?

HYPERTROPHY

- Either concentric or eccentric due to pressure or volume load

30

Left ventricular hypertrophy predicts what?

Left ventricular hypertrophy predicts a worse clinical prognosis in patients with hypertension and various cardiac diseases

31

Why do we measure ventricular response to stress?

- To assess overall ventricular reserve

- To determine functional significance of coronary stenosis in pts with CAD

32

Types of stress tests (3)? Examples?

- Isotonic exercise: treadmill and bike

- Isometric exercise: handgrip

- Pharmacologic: dobutamine, adenosine, or dipyridamole

33

What is a key predictor of significant coronary artery disease?

- Development of a regional wall motion abnormality INDUCED during any stress test is a HALLMARK of ischemia due to coronary artery disease (CAD)

- This is a major reason for using stress tests to assess regional ventricular function response to stress

34

What are measurements of diastolic function?

- Measure end-diastolic pressures in LV and RV during cardiac catheterization

- Diastolic filling parameters by Doppler echocradiography

35

Key points of measurements of cardiac function:

- Atrial waveforms:

- Ventricular waveforms:

- Ventricular Diastolic Pressure = ____

- RAP= __; RVP= __

- LAP= __; LVP= __

- Cardiac performance vs. contractility

- Systolic function: _____________

- Cardiac performance: measured by _________ & influenced by _______

- Contractility: ___________- conditions=inotropic state

- Systolic function: _______

- LVEDV= ___ ;LVESV=____; SV= ___

- EF= ___(%); EF= ______ 

- CO= ___; CI= ___

- SVR= _______ 

- Resistance= _____

Key points of measurements of cardiac function:

- Atrial waveforms: a, c & v (+); x & y (-)

- Ventricular waveforms: early/late filling

- Ventricular Diastolic Pressure = Atrial Pressure

- RAP=0-8; RVP=15-30/0-8 mm Hg

- LAP=3-12; LVP=100-140/3-12 mm Hg

- Cardiac performance vs. contractility

- Systolic function: volumes, EF, CO, SVR

- Cardiac performance: measured by EF, SV & CO & influenced by contractility

- Contractility: inherent ability to generate power independently of loading conditions=inotropic state

- Systolic function: volume, EF, CO, SVR

- LVEDV=79+11;  LVESV=28+6;  SV=D-S

- EF= SV/EDV (%); EF= 67+7 (>50%) 

- CO= SV x HR (volume ejected/beat x number of heart beats); CI= CO/BSA

- SVR= pressure drop (AP-RAP)/flow (CO) 

- Resistance = pressure/flow

 

36

All of the following are associated with pressure overload concentric LVH except:

A. Systemic hypertension

B. Aortic stenosis

C. Mitral regurgitation

D. Pulmonary hypertension

All of the following are associated with pressure overload concentric LVH except:

A. Systemic hypertension

B. Aortic stenosis

C. Mitral regurgitation

D. Pulmonary hypertension

37

Which of the following has the highest wall stress?

A. HTN with concentric LVH

B. Aortic stenosis with concentric LVH

C.

D.

Which of the following has the highest wall stress?

A. HTN with concentric LVH

B. Aortic stenosis with concentric LVH

C.

D. ***

38

which of the following is the correct way of calculating cardiac output?

A. SV x VR

B. HR x EDV

C. SV x HR

D. HR x CI

which of the following is the correct way of calculating cardiac output?

A. SV x VR

B. HR x EDV

C. SV x HR

D. HR x CI

39

All of the following affect wall stress except:

A. IVP

B. HR

C. Ventricular size

D. Wall thickness

All of the following affect wall stress except:

A. IVP

B. HR

C. Ventricular size

D. Wall thickness

40

Which of the following phases of diastole occurs first?

A. Atrial kick

Which of the following phases of diastole occurs first?

A. Atrial kick

41

True/False questions

?