BACK TO BASICS - HEMODYNAMIC ROUNDS - TRICUSPID VALVE

Hemodynamic Rounds

Dr.N.PraveenMD,DM (Cardiology)

Pressure Waveform Analysis and

Interpretation of Cardiac Pathophysiology

THE TRICUSPID VALVE

Introduction

• Right atrial pressure waveform reflects the function of and flow

across the tricuspid valve.

• The most commonly observed hemodynamic waveform.

• When assessing the small but clinically important gradients across the

tricuspid valve, two simultaneous and matched pressures from two

equisensitive transducers will provide the precise hemodynamics.

• Normal Right Atrial Waveforms

• Cardiac Rhythm and Right Atrial Pressure

• Systolic Regurgitant Waves

• Pulsatile Venous waves

• Right atrial –Right ventricular gradients

• Right Atrial Pressure Artifacts

Normal Right Atrial waveform has

• 1. A wave more than V wave

• 2.V wave more than A wave

• 3.X wave more than Y trough

• 4.X trough more than V wave

1. A wave more than V wave

2.V wave more than A wave

3.X wave more than Y trough

4.X trough more than V wave

Normal Right Atrial waveform

Important

• Simultaneous Right ventricular and right atrial pressure waves

to be measured using fluid filled transducer systems.

• Identical matching of the RA and RV diastolic pressures is the

norm for analysis.

• The “ A” wave (atrial contraction) of the right atrial pressure corresponds to the “A” wave of the right ventricle.

• The “V” wave corresponds to the opening of the tricuspid valveon the downslope of the RV pressure tracing.

• The pressure immediately after the “A” wave, the X descent, falls and does not begin to increase until late in systole.

X descent

Y descent • As RV pressure falls below the

RA pressure, the tricuspid valve

opens, releasing the atrial

pressure ( the Y descent of the

“V” wave).

• C wave – notch immediately after “A” wave or the initial upstroke

of ventricular pressure.

The higher ejection velocity and faster development of the RV

pressure causes more oscillations of the transducer system than that

of the RA pressure, and therefore, a high frequency “ringing” is

observed as a notch on the upstroke before the systolic peak of the

RV and a rapid dip (negative overshoot in early diastole.

• This common artifact using fluid filled systems is important to

recognize when assessing tricuspid and pulmonary gradients.

• 62 yr male, Aortic stenosis, Right atrial and left atrial pressure waveforms. Pullback of a fluid filled Transseptal Brockenbrough catheter.

• The mean left atrial pressure is elevated – approx. 22 mm Hg with striking A and V

waves.

• X trough – movement of the tricuspid or mitral valve away from the atrium when

intrapericardial pressure is decreasing immediately after ventricular contraction

begins and LV volume falls.

• Y trough – occurs with opening of the tricuspid valve.

• There is a reciprocal relationship between pressure and right atrial or venous flow.

• Flow is virtually absent at times of peak positive A and V waves.

• The left atrial V wave is giant (twice the mean pressure) and occurs in AS in absence of MR.

• V wave – pressure volume relationship of the atrium

• A non compliant or stiff ventricle is associated with large A and V waves.

• The Left atrial “ V ” waves are greater than V waves on the right atrial pressure where the A wave dominates.

• The atrial arrhythmias may significantly alter the waveforms (a’)

• Normal Right Atrial Waveforms

• Cardiac Rhythm and Right Atrial Pressure

• Systolic Regurgitant Waves

• Pulsatile Venous waves

• Right atrial –Right ventricular gradients

• Right Atrial Pressure Artifacts

• Right atrial pressure waves may be distorted during cardiac arrhythmias.

• The large, spiked waves represent “C” waves or giant cannon waves.

• This occurs when atrial contraction falls out of sequence with normal ventricular systole and the atria contract against a tricuspid valve closed by the increased right ventricular pressure during ejection.

• Size of the C wave is dependent on the timing of the atrial contraction relative to ventricular filling and the position of the tricuspid valve.

• Cannon waves to be differentiated from systolic tricuspid regurgitant waves.

• Can be iatrogenically induced – Pacemaker

• Can be spontaneously observed due to abnormalities in conduction.

• The pressure tracing demonstrates brief, sharp peaked waves, less prominent than the atrial contraction waves of the previous tracing.

• The dysynchronous ventricular pacemaker timing relative to atrial dissociated contraction appears responsible.The wider “C” type wave of beat 3 with the P wave falling on the QRS.

• The high pressure spike with narrow width also suggests artifact from catheter imapction,but the timing seqeunce is highly consistent with cannon type waves.

• Normal Right Atrial Waveforms

• Cardiac Rhythm and Right Atrial Pressure

• Systolic Regurgitant Waves

• Pulsatile Venous waves

• Right atrial –Right ventricular gradients

• Right Atrial Pressure Artifacts

• Positive systolic pressure waves on the right atrial tracing may

also be due to an incompetent or occasionally a stenotic

tricuspid valve.

• 50 year old woman with atrial fibrillation and history of rheumatic fever has increasing pedal edema and dyspnea. Simultaneous right ventricular and right atrial pressures were measured with two fluid filled catheters.

• The right atrial pressure, matching with right ventricular pressure in diastole.

• The right atrial and ventricular A waves are absent as patient is in atrial fibrillation.

• A prominent Y descent occurs after the point of maximal right atrial pressure (V wave) and falls sharply with the drop of RV pressure.

• Slope of the atrial pressure during RV ejection is generally proportional to the severity of TR.

• The compliance or pressure –volume relationship of the atrium will determine the size and character of the pressure wave.

Gradient rose across the systolic

period of right ventricular ejection, the

most common pressure wave pattern

of tricuspid regurgitation.

• Normal Right Atrial Waveforms

• Cardiac Rhythm and Right Atrial Pressure

• Systolic Regurgitant Waves

• Pulsatile Venous waves

• Right atrial –Right ventricular gradients

• Right Atrial Pressure Artifacts

39 year old woman, Severe ascites and dyspnea at rest has large V waves during jugular vein examination

and a pulsatile liver.

• The simultaneous right ventricular and right atrial pressure show the

marked and more striking upslope of right atrial pressure during right

ventricular ejection with a V or S systolic wave to 32 mm Hg.

• The more rapid rise of right atrial pressure indicates severe TR.

• Early diastolic ventricular pressure drop is associated with an early right

atrial right ventricular pressure gradient which equilibrates before the first

one third of diastole following a rapid decline – high flow and not

necessarily a significant tricuspid stenosis.

• The faster rate may also contribute to the early right atrial –right ventricular diastolic gradient.

• The regurgitant S wave, occuring slightly earlier than a V wave, is very prominent on physical examination and can be seen in the neck and even transmitted down to the femoral vein.

• Femoral vein pressure may be as high as 35 mm Hg.Thus , on puncture of the femoral vein, a venous pressure pulse may be observed.

• The timing of the V wave is coincident with the electrocardiographic T wave, but may be easily confused as an arterial pulse of low amplitude.

• Normal Right Atrial Waveforms

• Cardiac Rhythm and Right Atrial Pressure

• Systolic Regurgitant Waves

• Pulsatile Venous waves

• Right atrial –Right ventricular gradients

• Right Atrial Pressure Artifacts

• The right atrial pressure demonstrated prominent regurgitant wave with fusion of A and V waves with an absent X trough and a marked Y descent.

• The rhythm is atrial fibrillation

• A wave absent on RV tracing.

• The C wave of ventricular contraction can be seen.

• Because of the resonant qualities of some fluid filled systems,thepressure waveform with a blunted A wave and X descent may occasionally be confused with the M configuration of constrictive or restrictive physiology.

• The broad and wide upsloping right atrial pressure of TR is importantly associated with a persistent gradient of approximately 4mm Hg across the tricuspid valve throughout diastole.

• M pattern of constrictive physiology

• The first panel demonstrates elevated and matched right atrial pressures.

• The rhythm was atrial bigeminy.

• Loss of distinct right atrial A and V waves.

• Right atrial and right ventricular diastolic gradient can be seen.

• The gradient persists throughout diastole in both long and short cycles.

• Normal Right Atrial Waveforms

• Cardiac Rhythm and Right Atrial Pressure

• Systolic Regurgitant Waves

• Pulsatile Venous waves

• Right atrial –Right ventricular gradients

• Right Atrial Pressure Artifacts

• 1.The most common artifacts in the measurement of right atrial pressure icnlude failure to match the zero positions or transducer gain sensitivity of the 2 fluid systems.

• Importance : when tricuspid valve disease is suspected,precisecalibration and equisensitivity of transducers are critical because small gradients may have large clinical importance.

• An increase in right atrial mean pressure during inspiration is a

common sign of physiological abnormalities of atrial filling

especially prevalent in patients with constrictive or restrictive

physiology.

• Another common and disturbing artifact of fliud filled pressure

systems,especially in measuring right atrial and right heart

pressures is that of excessive catheter fling of an underdamped

pressure system.

• This artifact is very common with usage of balloon tipped

pulmonary artery flotation catheter.

• The left side of the figure shows right heart pressure recorded prior to pressure system manipulation to reduce the underdampened signal.

• Interpretation of waveforms and other details of these pressure tracings cannot be discerned from the rapid high frequency ringing artifact of the underdampened system.

• To improve hemodynamic recordings while continouslymeasuring pressure,a 50% saline and contrast solution to be instilled through the catheter.

Calibration of Pulmonary catheter

Reference

• Cathetrization and cardiovascular diagnosis 21:278-286(1990)

• Hemodynamic Rounds - Interpretation of cardiac pathophysiology from pressure waveform analysis

Morton J.Kern, Ubeydullah Deligonui