cath Lab Hemoduhynamic

17 DECEMBR 2015
POST GRADUATE CENTRE
MUNADIA MOHAMED

HEMODYNAMIC PRINCIPLES
Every electrical activity is followed normally by a
mechanical function (either contraction or
relaxation) resulting in a pressure wave.
The timing of mechanical events can be obtained by
looking at the ECG and corresponding pressure
tracings.
The amplitude and duration influenced by both
mechanical and physiological parameters (Force of
contraction of a chamber , Heart rate and
respiration).

CARDIAC PRESSURES
 Blood pressure is measured in various parts of the
circulatory system, most notably in the chambers of
the heart.
 Pressure is defined as the force per area hence what is
measured is the pressure exerted on the blood by the
heart and the force of the pumping action of the heart.
 A fluid filled catheter is attached to the pressure
transducer. The wave is transmitted from the catheter
tip to the transducer by fluid column in the catheter.

ELIMINATION OF SOURCES OF ERROR
 Calibrated pressure transducer
 Bubble free
 Low density liquid (e.g. NaCl 0.9%)
 Mid Chest level

MEAN ARTERIAL PRESSURE
 Mean Arterial Pressure (MAP) is defined as the
average arterial blood pressure during a cardiac cycle.
 It reflects the hemodynamic perfusion pressure of all
vital organs.
 MAP = [ ( 2x Diastolic ) + Systolic ] / 3
 A MAP of at least 60 is necessary to perfuse the
coronary arteries, brain and kidneys.
 Normal Range : 70 – 100mmHg

AORTIC PRESSURE
 The Aortic pressure shows the amount of contractile
force under which the blood has entered the systemic
circulation.
 Similar in shape to the pulmonary artery waveform
with a higher amplitude and no respiratory waveform (
normally).
 Normal Values:
 SYSTOLIC: 100 – 140 mmHg
 END DIASTOLIC : 60 – 90mmHg
 MEAN PRESSURE: 70 – 100mmHg

PULMONARY ARTERY
 The pulmonary artery channels blood from the right
heart into the lungs.
 During systole, when the pressure in the right ventricle
exceeds that of the pulmonary artery the pulmonic
valve opens and there is a rapid rise in pressure.
 The systolic peak corresponds to onset of the T wave
on the ECG.
 At end of systole with the onset of ventricular
relaxation, the pulmonic valve closes, reflected in the
dicrotic notch.
 Normal Range:
 SYSTOLIC: 15 -30 mmHg
 END DIASTOLIC : 3 – 12 mmHg
 MEAN PRESSURE: 9 - 16mmHg

Cont…..
 High pulmonary artery pressures seen with:
Pulmonary Emboli
MV Stenosis
COPD
Pulmonary Hypertension
Left Ventricular Failure
Peripheral PA Stenosis

VENTRICULAR PRESSURES
 Right and left ventricular morphology is similar
 Differs with respect to the magnitude of pressure.
 RIGHT VENTRICLE:
 The function of the right ventricle is to pump venous blood
into the pulmonary circulation.
 The mechanical systole begins at the end of QRS complex
on the ECG.
 The RVEDP, is the pressure in the ventricle when the
atrium has completed its contraction and the tricuspid
valve closes just as the ventricular contraction begins.
 RVEDP indicates how well the ventricle is filling, how well
hydrated the patient is and how elastic myocardium is.

VENTRICULAR PRESSURES
 LEFT VENTRICLE:
 The left ventricle is responsible for generating enough
contractile force to pump blood throughout the body.
 The LVEDP is the pressure at the end of diastole in LV.
Corresponds to the R Deflection of the QRS complex.
 High LVEDP caused by:
 Aortic valve insufficiency
 Abnormal Diastolic function
 Normal Values:
 SYSTOLIC: 100 - 140 mmHg
 END DIASTOLIC : 3 - 12 mmHg

RIGHT ATRIAL PRESSURE
 3 Positive deflections (a, c and v waves)
 2 negative deflections (x, y)
 The A wave is caused by a rise in pressure in the atrium
during atrial contraction, follows the P wave on the
ECG.
 Height depends on force of contraction and resistance
to RV filling.
 The x descent follows the A wave.
 Relaxation of the atrium (Pressure in the atrium falls).

RIGHT ATRIAL PRESSURE
 The c wave : As the pressure in the ventricle increases
the tricuspid valve closes, which causes a small
increase in the pressure in atrium.
 The c wave is found in line with the end of the QRS
complex on the ECG.
 The v wave : When atrial contraction is completed and
TV is closed, the pressure in atrium falls.
 Followed by passive atrial filling.
 Height depends on RA compliance and amount of
blood returning from periphery.
 Smaller than a wave

VENOUS PRESSURES
 The y descent:
 After the v wave
 During ventricular relaxation phase, the pressure in
the right ventricle falls below that of the right atrium
and the tricuspid valve opens emptying blood into the
RV.
 The atrial pressure decreases, causing a downstroke in
the waveform, known as the y descent.
 Normal Values:
 Mean: 0 – 8mmHg
 A wave: 2 – 10mmHg
 V wave: 2 – 10mmHg

PULMONARY CAPILLARY WEDGE PRESSURE

PULMONARY CAPILLARY WEDGE PRESSURE
 Similar to LA pressure waveform.
 Objective is to position the catheter to measure the
pressure on the left heart side of the pulmonary tree by
temporarily obstructing proximal blood flow from the
right heart by balloon-tipped catheter.
 A wave is found near the QRS complex.
Causes of error.
 PCW = LA pressure, except when PVR is increased.
 Damped and delayed due to transmission through the
lungs.
 Not properly occluded capillary or not proper position.

RESISTANCE
Pulmonary Vascular Resistance
 Total Peripheral Resistance (TPR) is vascular
resistance to the systemic circulation.
 Resistance is ΔP/Flow
 Peripheral Vascular Resistance (PVR) is vascular
resistance of the pulmonary circulation.
PVR = PA mean – PCW mean /Qp

RESISTANCE
Systemic Vascular Resistance
 Resistance = ΔP/Flow
 Systemic circulation is a high resistance, high pressure
circuit
 Pulmonary circulation is a low resistance, low pressure
circuit.
SVR = RA mean – Ao mean/Qs

REFERENCES
 1. A Manual For Cath Lab Personnel 3rd Edition, 2000, Watson, S ;
Gorski K.A K.L. Gould, R.L. Kirkeeide, M. Buchi
 Coronary flow reserve as a physiologic measure of
stenosis severity J Am Coll Cardiol, 15 (1990), pp. 459–474
 http://content.onlinejacc.org/article.aspx?articleid=2474632&result
 http://circimaging.ahajournals.org/content/6/6/881.abstract
 Hand book of cardiac hemodynamic and function Jonathon Leipsic,
MD and James K. Min, MD 2004 5th edition. CA USA.
 http://www.cathlabdigest.com/article/Test-Your-Hemodynamic-
Knowledge-Part-II%E2%80%93-Answer-Key
 http://www.invasivecardiology.com/

What is the pathology of above tracing ?
Question 1.

Question 2.
What is the pathology of above tracing ?

Answer
 AS with PDA.
 Catheter pulls back from LV-AO (with35 mm
gradient) then through PDA, into PA (with 13
mm gradient) and finally into RV.

cath Lab Hemoduhynamic

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