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CVT Senior Monitor
CVT Senior Monitor
35
Medical
Professional
06/07/2013

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Term
Given a cardiac pressure, list the normal values
Definition
RA:
Mean: 0-8
a-wave: 2-10
v-wave: 2-10

RV:
Systolic: 15-30
End Diastolic: 0-8

PA:
Systolic: 15-30
Diastolic: 5-14
Mean: 10-22

PCWP:
a-wave: 5-15
v-wave: 5-15
Mean: 4-12

LA:
Mean: 4-12
a-wave: 5-15
v-wave: 5-15

LV:
Systolic: 90-150
End Diastolic: 4-12

AO:
Systolic: 90-150
Diastolic: 60-90
Mean: 70-105
Term
State how a pressure wave is created
Definition
A pressure wave is created by cardiac muscular contraction and is transmitted along a closed, fluid-filled column (catheter) to a pressure transducer, converting the mechanical pressure to an electrical signal that is displayed to a video monitor.
Term
Define mean pressure
Definition
Mean pressure is the time-averaged pressure of the pulse. It can be obtained by means of either planimetric integration or damping of the pressure.
Term
Given a method of determining cardiac output, choose when that method is most appropriate
Definition
-Fick (oxygen consumption method)- the most accurate method of assessing cardiac output, particularly in patients with low cardiac output. Simultaneous reliable measurements of the arteriovenous oxygen content difference and oxygen consumption are crucial for an accurate value. Supplemental oxygen therapy should be discontinued at least 10 to 15 minutes before determination of CO. If oxygen cannot be discontinued safely, an alternative to the Fick technique should be used

-Indicator Dilution Co (Thermodilution Indicator Method)- The thermodilution technique is inaccurate with tricuspid regurgitation or low CO. Shunts further reduce the accuracy of thermodilution

-Indocyanine Green Method- The indocyanine method for shunt studies is no longer used. Indicator dilution curves for shunts.

-Angiographic Cardiac Output- Provides the best estimate of CO through a stenotic valve when any degree of regurgitation is present. Errors in stroke volume computation are increased with enlarged ventricles, especially when single plane cineangiography is employed.
Term
State the cause of each wave and it’s negative descent in the atrial pressure contours
Definition
A wave
–atrial kick
-Succeeds the P wave

X descent
-atrial relaxation (45)

C wave
-AV valve closes (45) Page 2
-Isovolumetric contraction begins
-Ventricular systole begins
-AV valves bulge into the atrium
-Begins at Z point

X’ descent
-at the beginning of the wave, isovolumetric contraction ends
-Aortic valve opens
-Ventricular ejection begins
-Downward pulling of the septum/descent of the AV ring

V wave
-Atrial filling during ventricular systole.
-Takes place at the end of the “T” wave or the TP interval.
-Towards the end of the V wave:
-Ventricular ejection begins
-Isovolumetric relaxation begins
-Aortic Valve closes

Y descent -
-AV valve opens
-Rapid ventricular filling begins
Term
List the indications for a right heart catheterization
Definition
-Patients with a history of dyspnea
-Valvular heart disease
-Intracardiac shunts
Term
List the causes of an elevated PCWP
Definition
-LV Failure
-Mitral stenosis and regurgitation
-Severe AS and AI (late symptom)
-The a-wave of the PAW pressure tracing reflects left atrial systole, and will therefore be elevated in conditions which elevate left atrial systolic pressure.
Term
State the formula for determining mean pressure
Definition
-Mean Pressure = (1 sys + 2 diast)/3
Term
Given statements regarding left and right atrial tracings, choose the correct statement
Definition
-In early LV failure, the LVEDP is elevated which results in an elevated a-wave on the PAW tracing reflecting an increase in pressure, and a decrease in the v-wave reflecting the decrease in LV pressure.
-Tricuspid Insufficiency-The blood regurgitates from the RV into the RA causing an increased v-wave.
-Explain the difference between physiological regurgitation and the regurgitation as a disease state.
-Physiological regurgitation is not usually seen on an atrial waveform. If regurgitation is seen on the atrial waveform, is normally a result of a more severe degree than physiological.
Term
Select or list the complications of a right heart catheterization
Definition
The most common is the stimulation of the RVOT which results in:
•Arrhythmias
•Advanced AV Block
•Rare Right Bundle Branch Block
•Significant but transient arrhythmias in 30% - 60% of patients

Access:
-Major: Pneumothorax, Hemothorax, Tracheal perforation (subclavian route), Sepsis.
-Minor: Hematoma, thrombosis, cellulites

Intracardiac:
-Major: Right ventricular perforation, Heart Block (RBBB), Pulmonary rupture, Pulmonary infarction.
-Minor: Ventricular arrhythmias
Term
Define pressure gradient
Definition
-A pressure gradient is defined as the pressure difference across an area of valvular or vascular obstruction, such as a stenosis or an occlusion or narrowed valve.
Term
Given a ventricular pressure wave, select the components of the systolic phase
Definition
-Isovolumic contraction
-Rapid ejection
-Slow ejection
-Protodiastole (early diastole)
Term
List the leads examined to determine if a patient has a left or right bundle branch block
Definition
-Right Bundle Branch Block can be found in leads V1, V2
-Left Bundle Branch Block can be found in leads V5, V6
Term
Given a ventricular pressure wave, select the components of the diastolic phase
Definition
-Isovolumic relaxation
-Passive filling (rapid filling and slowed filling/diastasis)
-Atrial kick
Term
Given a component of the diastolic phase of the ventricular pressure wave, choose the correct statement regarding that component
Definition
-Diastasis – There is a gradual increase in the ventricular pressures.
-Protodiastole – very early, brief phase of diastole, during which there is reversal of blood flow in the PA and AO as ventricular pressures fall below the pressures within in the roots of the PA and AO. Retrograde blood flow results in distention and closure of the pulmonic and aortic valves. Protodiastole ends when the rapidly declining ventricular pressure falls below that of the corresponding great artery and the semilunar valve closes.
-Isovolumetric relaxation – the ventricular muscle fibers are relaxing and losing tension while the semilunar and the AV valves are closed obviating any changes in ventricular volume. It begins with the closure of the Semilunar valve ..and ends with the opening of the AV valve.
-Passive filling – When the ventricular diastolic pressure falls below the atrial pressure, the AV valve opens, resulting in blood rushing into the ventricle. This is termed rapid filling, where 60% of the filling can occur. In mid to late diastole, filling of the ventricles becomes progressively slower, as atrial and ventricular pressures reach diastasis (period of slow filling)70% - 90% of ventricular filling occurs throughout the combined rapid and slowed filling phases.
-Atrial systole – the atrial contribution to ventricular filling, which adds about 10% - 30% ventricular end-diastolic volume. Augmented end-diastolic filling, in turn, increases the end-myocardial fiber length, the force of the subsequent ventricular contraction, and the stroke volume.
Term
List the artifactual variables that affect accurate measurements of pressure gradients
Definition
Artifactual variables that affect pressure gradients
-Miscalibrated pressure transducers
-Pressure leaks on catheter manifold or connecting tubing
-Pressure tubing type, length, and connectors
-Air in system
-Catheter sizes(especially small diameters)
-Fluid viscosity
-Position of catheter side holes
Term
State the formulas for Fick cardiac output, cardiac index, and SVR
Definition
COMPUTATIONS FOR HEMODYNAMIC MEASUREMENTS
Fick Cardiac Output
- O2 consumption (ml/min)/
AVO2 difference (ml/O2/100ml blood) x10


Cardiac Index
-Cardiac output(L/Min)/BSA (m2)

SVR
-Mean systemic atrial pressure – mean right atrial pressure x80/CO
Term
Given a component of the systolic phase of the ventricular pressure wave, choose the correct statement regarding that component
Definition
-Isovolumetric contraction – increase in pressure as a result of ventricular muscle contraction without any change in ventricular volume. This is because both, the semilunar and AV valves are closed. Begins with the closure of the AV valves.(34)Page 3
-Rapid ejection – Due to a continued increase in ventricular pressure, the semilunar valves are forced open, and the blood is rapidly ejected into the main arteries (PA or AO). 60% of ejection occurs here.
-Reduced ejection – characterized by a drop in ventricular pressure, even though some blood is still being pumped into the main arteries. 40% of ejection occurs here.
-The ejection phase begins with the opening of the semilunar valve and it ends with the beginning of the protodiastole.
Term
Given an area of the heart that has suffered a myocardial infarction, name the leads used to confirm the location
Definition
-Anterior:
Q’s in V1, V2, V3 and V4 (Anterior Descending Coronary Artery)

-Lateral:
Q’s in I and AVL V5 & V6 (Circumflex Coronary Artery)

-Inferior(Diaphragmatic):
Q’s in II, III, and AVF (R. or L. Coronary Artery)

-Posterior:
Large R with ST depression in V1 & V2 (Right Coronary Artery)
Mirror Test
Term
State the formula for a quick, in-lab determination of aortic valve area
Definition
Quick in-lab determination of Aortic valve (Hakki’s formula):

-Quick valve area =

CO L/min / Peak-to-peak gradient mmHg
Term
Given a condition regarding catheter selection for aortic stenosis, select the correct statement
Definition
-Pigtail Ventriculography Catheter
-Amplatz Left
-Amplatz Right
-Judkins Right
-Multipurpose
-Other specially designated catheters.
Term
State the Fick principle for measurement of Cardiac output
Definition
-The Fick Principal states that uptake or release of a substance by any organ is the product of the arteriovenous concentration difference of the substance and the blood flow to that organ.
Term
Select the correct points to remember when using guide wires to cross the aortic valve
Definition
-Adequate Heparin ( 5000 Units Bolus), frequent catheter flushing
-Maximum time of 3 minutes per crossing attempt is required before wire withdrawal, wiping, and flushing of the catheter.
-A 0.035” guidewire may be insufficiently stiff to support the catheter on crossing the severely deformed, calcific aortic valves, and a 0.038” guidewire should be substituted. Large catheters that accept this size of wire should be used.
-Guidewire configurations that lead to the coronary ostia should be avoided to prevent dissection of the coronary arteries, which would complicate this otherwise benign maneuver.
-Manipulation of the wire should be gentle to avoid damaging the valve, lifting atheromas, or causing a perforation of the cusps or aortic root.
Term
Given a condition needed to accurately use the Fick oxygen consumption method, choose the correct procedure
Definition
-CO is calculated as oxygen consumption divided by the arteriovenous oxygen concentration difference. (13)

-Determination of oxygen consumption requires that patients breathe comfortably at a steady state. If a steady state cannot be achieved due to anxiety, dyspnea, or any condition where oxygen is spuriously elevated, an abnormally high cardiac output will be calculated.(31)

-Shallow breathing (alveolar hypoventilation), commonly seen with oversedation, results in falsely low oxygen consumption and, therefore, a low CO determination.

-Mixing the supplemental oxygen with room air, makes determination of the oxygen content of the inspired air, difficult (if not impossible) to calculate. Oxygen should be discontinued, at least 10 – 15 minutes before the determination of CO by Fick technique.

-If Oxygen cannot be safely discontinued, an alternative to the Fick Technique should be used.
Term
List the different division of the autonomic nervous system
Definition
Autonomic Nervous System –
Consist of a sympathetic system and an opposing parasympathetic system.

-SYMPATHETIC:
Terminal Sympathetic nerve ends (synaptic boutons)
Cell receptors called adrenergic receptors

-PARASYMPATHETIC:
Terminal Parasympathetic nerve ends (synaptic boutons)
Cell receptors called cholinergic receptors
Term
Given a principle, in which Fick and or indicator dilution cardiac output method is based on, select the correct one
Definition
FICK PRINCIPAL FOR MEASUREMENT OF CARDIAC OUTPUT:
-Uptake or release of a substance by any organ is the product of the arteriovenous concentration difference of the substance and the blood flow to that organ.

INDICATOR DILUTION CARDIAC OUTPUT PRINCIPLE:
-A single injection of a known amount of an indicator (e.g., cold saline for the thermodilution technique) injected into the central circulation mixes completely with blood and changes concentration as it flows to a more distal location. The change in the indicator concentration (or temperature) is plotted over time; the area under the curve is planimetered to calculate CO.
Term
List three proposed explanations for the c-wave on the left atrial waveform
Definition
-Reflecting closure of the tricuspid valve.
-Corresponds with the RST junction of the EKG.
-Result from upward bulging of the AV valves early in ventricular systole and partially from pressure waves transmitted to the atria from large nearby arteries.
-May result due to closure of the tricuspid valve leaflets.
-At the beginning of “c” wave, AV valve closes, Isovolumetric contraction begins and ventricular systole begins.
Term
Given a list of statements, select the correct one regarding the timing of electrical events on an EKG compared to actual cardiac mechanical events
Definition
-The “a” wave, immediately succeeds electrical atrial depolarization, that is, after the P wave of the EKG. The “a” wave of the atrial pressure is generally seen 80 – 100 msec after the P wave, or at some time during the P-R interval of the EKG.
-The ventricles begin to contract approximately 6 msec following the QRS. The ventricular systole also corresponds with the QT interval of the EKG.
-About three-fourths of the way through the P wave of the ECG (the electrical event) the atria contract (mechanical event).(32)Page 6
-About halfway through the QRS complex (the electrical event), the ventricle begins to contract (the mechanical event)
Term
Given a list of statements, select the correct one regarding the hemodynamic setup used for recording of optimal pressure measurements
Definition
-The zero level is set at mid chest. When the transducer is raised above the zero level, pressure is artificially lower. When the transducer is lower than the zero level, pressure is artificially higher. (14,15)Page 164
-When abnormally low pressures are seen initially, recheck the zero for proper positioning (at midchest) and detection of air bubbles or loose connections.
Term
Given a certain condition, choose the one(s) that might show up as an abnormality in the right atrial, right ventricle, pulmonary artery, or pulmonary arterial capillary wedge waveforms
Definition
Right Atrium
Increased:
-RV failure secondary to left heart dysfunction: mitral stenosis and mitral regurgitation, LV Failure
-RV failure secondary to factors that increase pulmonary vascular resistance (tone): pulmonary embolism, hypoxemia, COPD, ARDS, sepsis and shock.Hypervolemia.
-RV failure due to intrinsic disease: RV infarction, cardiomyopathies. As the RV fails, the mean RA pressure would increase.
-Cardiac tamponade/effusion.
-Intravascular volume overload.
Decreased
-Hypovolemia
Alterations in Waveform
-Large “a” waves: RV failure, Tricuspid stenosis, sporadic appearance in AV dissociation.
-Large “v” waves: tricuspid insufficiency.

Right Ventricle
Systolic pressure:
-Increased: COPD, pulmonary embolism, hypoxemia, ARDS, sepsis, pulmonary vascular volume overload due to left heart dysfunction or left to right shunts as VSD or ASD.
-Decreased: RV failure due to ischemic disease or myopathies.
Diastolic pressure:
-Increased: All factors that increase RA pressures
-Decreased: Hypovolemia
Alterations in Waveform
-Pulse pressure narrow in severe RV failure, hypovolemia giving damped-appearing tracing
-Pulse pressure wide in ASD or VSD
-Initially, in RV failure the pressure tracing would show decreased systolic and an increased end-diastolic pressure.

Pulmonary artery
Systolic pressure
-Increased: pulmonary hypertension(causes elevated PA systolic; diastolic; and mean pressures but a normal PCW), pulmonary embolism, hypoxemia, COPD, ARDS, sepsis, shock.
-Decreased: hypovolemia
Diastolic pressure
-Increased: pulmonary hypertension, pulmonary vascular disease, intravascular volume overload, left heart dysfunction of any type, LV failure, in mitral stenosis, the Pad pressure would be elevated, insufficiency, decreased LV compliance, cardiac tamponade/effusion.
-Decreased: hypovolemia.
Alterations in waveform
-Retrograde “v” waves may distort the PA pressure waveform in acute or severe mitral regurgitation.
-Pulse pressure narrow in tamponade or shock states.
-Pulse pressure wide in VSD or ASD.

Pulmonary Artery Wedge Pressure
Increased:
-Left heart dysfunction: mitral stenosis/insufficiency, LV failure
-decreased LV compliance
-Intravascular volume overload
-Tamponade/effusion
Decreased:
-Hypovolemia
Alterations in waveform
-Large “a” waves: mitral stenosis, LV failure
-Large “v” waves: mitral insufficiency
-Sporadic appearance in atrioventricular dissociation
Term
Select the correct use of the peak to peak and mean pressure gradients when determining the degree of aortic stenosis
Definition
-The mean pressure gradient is measured by planimetry of the superimposed aortic and LV pressure tracings.
-Peak-to-peak pressure gradients are easily seen and are often used as an estimate of the severity of stenosis.
-The peak to peak gradient is not equivalent to mean gradient for mild and moderate stenosis, but it is often close to mean gradient for severe aortic stenosis.
Term
Name the types of leads found on a standard twelve lead EKG
Definition
A standard EKG is composed of six limb leads:
-I, II, III, AVR, AVL, AVF

There are also six chest leads:
-V1, V2, V3, V4, V5, V6
Term
Given a patient with right or left atrial hypertrophy, state or select the correct configuration of the P-wave
Definition
-Right atrial hypertrophy: Large, diphasic P wave with tall initial component.
-Left atrial hypertrophy: Large, diphasic p wave with wide terminal component.
Term
State which leads are unipolar, bipolar, limb, or chest leads
Definition
Unipolar – AVR, AVL, and AVF
Bipolar – I, II, III
Limb – I, II, III, AVR, AVL, AVF
Chest – V1, V2, V3, V4, V5, V6
Term
Select or state the effects of stimulating one of the divisions of the autonomic nervous system
Definition
The effects of stimulating the Parasympathetic system include:
-Decreased rate of SA node pacing
-Decreased rate of conduction
-Decreased force of contraction
-Decreased irritability of atrial and junctional foci
-Dilates arteries
-Decreased BP
-Marked Bradycardia
-Syncope

The effects of stimulating the sympathetic system include:
-Increased rate of SA node pacing
-Increased rate of conduction
-Increased force of contraction
-Increased irritability of foci
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