'Assessment of Valves' - Emergency Ultrasound

Aortic Valve4

Aortic ValveComposed of 3 cusps of equal sizeWhen viewed from a conventional TTE short-axisprojection the closure lines of the 3 cusps forms a ‘Y’shapebehind each cusp there is a sinus of valsalva.The left and right coronary arteries arise from theleft and right sinuses respectively, and are associatedwith the left and right cuspsNormal aortic valve area: 2.5 - 3.5 cm 2 5

Aortic StenosisNormal area of the aortic valve is > 2cm 2Significant narrowing restricts LV outflow imposing apressure load on the LVLeads to Hypertrophy of the LVSymptoms: Exertional anginaDyspnoeaExertional syncope6

Aortic StenosisAS may occur at 3 Levels - ValvularValvular ASSubvalvularSupravalvularRheumatic Heart Disease: Usually associated with mitral valvediseaseCalcific (degenerative) ASCongenital Bicuspid Valve (1-2% of the population)7

Aortic valveRCCNCCRCCLCCNCC9

Aortic StenosisMobilityIs it normal or reduced?Is there systolic bowing? (Bicuspid, Rheumatic)Is there diastolic prolapse (Floppy valve, tear, bicuspid)10

Aortic Stenosis13

Aortic StenosisSevere Aortic Stenosis14

Aortic StenosisMild Aortic Stenosis15

Severe Aortic Stenosis16

Assessment of the LV inAortic StenosisLook for hypertrophy of the LV which suggests(but Does not Prove) severe stenosis(IVS / Posterior wall >11mm in Diastole)If the LV function is impaired, the transaorticpressure difference may underestimate theseverity of the stenosis17

Aortic StenosisAortic Stenosis with Severe LV Dysfunction18

Aortic StenosisQuantification of AS severity usingContinuous wave Spectral DopplerMeasure Maximum aortic jet velocityCalculate maximum and mean transaorticpressure gradientscalculate the effective orifice area19

Trans-Aortic Jet VelocityMeasure the continuous waveform of theaortic jet from the apexNormal trans-aortic jet velocity is 1.0 - 1.7 m/sAortic Vmax: Mild Stenosis: 2.0 - 3.0m/sModerate Stenosis: 3.0 - 4.5m/sSevere Stenosis: > 4.5m/s20

Trans-Aortic Jet Velocity21

Peak & Mean Aortic valvePressure GradientsThe peak & mean pressure gradients across theaortic valve can be calculated from themaximal aortic jet velocity using theBernoulli Equation22

Peak & Mean Aortic valvePressure GradientsNB:If there is co-existent LV systolic dysfunctionthere may be a decreased trans-aortic pressuregradient and so the severity of the AorticStenosis will be underestimatedIf there is coexistent aortic regurgitationthere will be increased trans-aortic volumeflow which will increase the trans-aorticpressure gradient and therefore moderate tosevere AR may overestimate the severity ofthe Aortic Stenosis23

Severity in aortic stenosis______________________________________________________Mild Moderate Severe____________________________________________________________________________Aortic Vmax (m/s) 2.0 - 3.0 3.0 - 4.5 >4.5Peak Gradient (mmHg) < 40 40 - 80 > 80Mean Gradient (mmHg) < 20 20 - 50 > 50EOA (continuity eqn) >1.0 0.6 - 1.0 < 0.6(cm 2 )24

Aortic Stenosis: SummaryValve anatomy: Aetiology of stenosisExclude other causes of left ventricularoutflow obstructionStenosis severity: Jet velocityMaximum & Mean Pressure GradientEffective valve areaDegree of co-existent aortic regurgitationLeft ventricular hypertrophy & systolicfunction25

Mitral Valve26

Mitral ValveAnatomyMitral valve apparatus includes the mitral annulus,the leaflets, chordae tendineae papillary muscles andthe underlying ventricular wallThere are 2 mitral valve leaflets; anterior andposterior, the anterior being the larger.Each leaflet is divided into 3 scallopschordae attached throughout the entire length of thecoaptation line and insert into the tips of thepapillary apparatus27

Mitral Valve2 major papillary musclesAnterolateral Papillary Muscle:chordae to anterolateral half of both mitral valvesDual blood supplyPosteromedial Papillary Muscle:Chordae to posteromedial half of both mitral valvesPerfused by RCAZona Coapta: Coaptation of the mitral valve iscomplex and involves overlap of the mitral valvetissueNormal Mitral Valve area: 4-6cm 2 28

Parasternal Long-Axis29

Parasternal Short-Axis30

Apical 4-Chamber31

Mitral RegurgitationAetiologyIschaemic:restricted posterior leafletprolapsepapillary muscle rupture or dysfunctionFunctionalFloppy Mitral ValveRheumaticEndocarditisOther ie SLE32

Mitral RegurgitationFeatures of MRAcute vs ChronicLV volume overload with dilatationLA dilatation33

Assessment of Mitral RegurgitationAppearance & Movement of the valve leafletsColour flow mappingContinuous wave DopplerLeft Ventricular FunctionPulmonary Artery Pressure34

Appearance & MovementWhat is the distribution and degree of any leafletthickening?Is there a discrete echogenic mass (e.g. vegetation)?Does the valve open normally during diastole or isthere bowing to suggest of the leaflets to suggestrheumatic disease?Is there evidence of leaflet prolapseIs there restriction of the posterior leaflet duringsystole?35

estricted posterior mitral valve leaflet36

Posteriorly directed MR jet due to restriction of theposterior mitral valve leaflet37

MR in a patient with dilated cardiomyopathy and apicaldisplacement of the papillary muscles leading to functionalmitral regurgitation38

severe functional mr associated with apical displacementof the papillary Muscles39

Colour Flow MappingColour Doppler imaging is the primaryechocardiographic tool for the detection andquantitation of Mitral regurgitationAssess the width of the base of the jet at thelevel of the valveAssess the jet area40

Mitral Regurgitationreproduced from: Echocardiography a practical guide for reporting42

Continuous Wave DopplerAssess the density of the Continuous WaveDoppler signalThe intensity of the jet is greater with moresevere mitral regurgitation43

Mild RegurgitationModerate RegurgitationSevere Regurgitation44

Left Ventricular FunctionBy definition, haemodynamically significantmitral regurgitation results in volumeoverload of the left ventricle withsubsequent LV & LA dilatationThe increased LA pressure will lead topulmonary congestion45

Mitral RegurgitationIndicators of degree of mitral regurgitationMildSevereJet width at base (cm) 1Jet area (cm 2 ) 8.0Density on CW Doppler + ++46

Mitral Regurgitation: SummaryValve anatomy and movement: Aetiology ofregurgitationAssess severity using colour flow mapping &continuous wave DopplerAssess for LV dilatation and systolicdysfunctionAssess for other valve disease47