Echo ConferenceEcho ConferenceAortic Aortic
RegurgitationRegurgitationSeptember, 2007September, 2007
Christopher Dibble, M.D.Christopher Dibble, M.D.
Aortic Regurgitation:Aortic Regurgitation:SymptomsSymptoms
Dyspnea, orthopnea, PNDDyspnea, orthopnea, PND Chest pain.Chest pain.
Nocturnal angina >> exertional angina Nocturnal angina >> exertional angina (( diastolic aortic pressure and increased diastolic aortic pressure and increased
LVEDP thus LVEDP thus coronary artery diastolic flow) coronary artery diastolic flow) With extreme reductions in diastolic With extreme reductions in diastolic
pressures (e.g. < 40) may see anginapressures (e.g. < 40) may see angina
Peripheral Signs of Peripheral Signs of Severe Severe
Aortic RegurgitationAortic Regurgitation Quincke’s sign: Quincke’s sign:
capillary pulsationcapillary pulsation Corrigan’s sign: water Corrigan’s sign: water
hammer pulsehammer pulse Bisferiens pulse Bisferiens pulse
(AS/AR > AR) (AS/AR > AR) De Musset’s sign: De Musset’s sign:
systolic head bobbing systolic head bobbing Mueller’s sign: Mueller’s sign:
systolic pulsation of systolic pulsation of uvulauvula
Durosier’s sign: Durosier’s sign: femoral retrograde femoral retrograde bruitsbruits
Traube’s sign: pistol Traube’s sign: pistol shot femoralsshot femorals
Hill’s sign:BP Lower Hill’s sign:BP Lower extremity >BP Upper extremity >BP Upper extremity by extremity by > 20 mm Hg - mild AR> 20 mm Hg - mild AR > 40 mm Hg – mod AR> 40 mm Hg – mod AR > 60 mm Hg – severe > 60 mm Hg – severe
ARAR
Wave Sound
Aortic RegurgitationAortic Regurgitation
Can be a caused by:Can be a caused by: Valve DiseaseValve Disease Aortic root diseaseAortic root disease
Percentage of aortic root disease steadily Percentage of aortic root disease steadily increasing over past few decadesincreasing over past few decades
Root disease now accounts for >50% of all Root disease now accounts for >50% of all AVRsAVRs
AR – Valvular diseaseAR – Valvular disease
Rheumatic diseaseRheumatic disease Cusps become fibrotic and retractCusps become fibrotic and retract Usually also stenoticUsually also stenotic MV is involvedMV is involved
Calcific ASCalcific AS At least mild AR in 75% of patientsAt least mild AR in 75% of patients
AR – Valvular disease IIAR – Valvular disease II
Infective endocarditisInfective endocarditis Leaflet perforationLeaflet perforation Vegetation interferes with coaptationVegetation interferes with coaptation
TraumaTrauma Bicuspid ValveBicuspid Valve
Can isolated regurgitation or stenosis, or Can isolated regurgitation or stenosis, or bothboth
Complication of catheter based Complication of catheter based ablationablation
AR – Valvular disease IIIAR – Valvular disease III Myxomatous degenerationMyxomatous degeneration Structural deterioration of bioprosthesisStructural deterioration of bioprosthesis Less common causes:Less common causes:
SLE, RASLE, RA Ankylosing spondylitisAnkylosing spondylitis Jaccoud arthropathyJaccoud arthropathy Takayasu diseaseTakayasu disease Whipple’s diseaseWhipple’s disease Anorectic drugsAnorectic drugs Congential (rare, usually associated with Congential (rare, usually associated with
bicuspid valve)bicuspid valve) Membranous subaortic stenosisMembranous subaortic stenosis
Aortic root diseaseAortic root disease
Between aorta Between aorta proper and the proper and the annulus is a tube annulus is a tube composed of composed of collagen that forms collagen that forms sinuses of valsalvasinuses of valsalva
Dilation here is rare
Dilation here is common; especially in AS; does not lead to AR
As little as 2mm of
dilation here can cause AR
Dilation of the Dilation of the aortic ridge aortic ridge eliminates the eliminates the normal overlap of normal overlap of the valvesthe valves
Aortic root diseaseAortic root disease
AR – Aortic Root DiseaseAR – Aortic Root Disease
Age related (degenerative)Age related (degenerative) Systemic HypertensionSystemic Hypertension Aortic dissectionAortic dissection Cystic medial necrosis Cystic medial necrosis
either isolated or associated with either isolated or associated with Marphan syndromeMarphan syndrome
Bicuspid valveBicuspid valve
AR – Aortic Root Disease AR – Aortic Root Disease IIII
Syphilitic aortitisSyphilitic aortitis Osteogenesis imperfectaOsteogenesis imperfecta Ankylosing spondylitisAnkylosing spondylitis Relapsing polychondritisRelapsing polychondritis Ehlers-DanlosEhlers-Danlos Inflammatory bowel diseaseInflammatory bowel disease
AR – M-ModeAR – M-Mode
As the aortic jet cascades across the As the aortic jet cascades across the anterior MV leaflet it can create a anterior MV leaflet it can create a high frequency flutteringhigh frequency fluttering
In acute AR premature closure of the In acute AR premature closure of the MV can be seenMV can be seen Due to rapidly increasing LV pressureDue to rapidly increasing LV pressure
AR - M-modeAR - M-mode
•Fluttering of Anterior Mitral Valve leaflet•Increased duration between E and A peaks•Early example of using M-mode to indirectly assess valve disease
AR – 2D imagingAR – 2D imaging
Detailed evaluation of valve and rootDetailed evaluation of valve and root Detailed evaluation of LV size and Detailed evaluation of LV size and
functionfunction Many important causes of AR easily Many important causes of AR easily
seen on 2D evaluationseen on 2D evaluation Even when AR is severe, sometimes Even when AR is severe, sometimes
2D imaging is suprisingly normal2D imaging is suprisingly normal
AR – 2D ImagingAR – 2D Imaging
AR – Doppler EvaluationAR – Doppler Evaluation
Pulsed, continuous wave, and color Pulsed, continuous wave, and color flow Doppler are highly sensitive for flow Doppler are highly sensitive for detection of regurgitation and are detection of regurgitation and are complementary studies complementary studies
Use of Doppler to Detect Use of Doppler to Detect Regurgitant JetsRegurgitant Jets
Most Most regurgitant regurgitant jets >1.5 jets >1.5 m/secm/sec
CW lacks CW lacks spatial spatial resolutionresolution
PW needed to PW needed to map location map location and direction and direction of jetof jet
Mitral Inflow
Helpful for flow profile; gradient
Identifies turbulence in an area; color flow
derived from PW data
AR – Pulsed DopplerAR – Pulsed Doppler
Early to assess severity of AR used Early to assess severity of AR used pulsed Doppler to “map” ARpulsed Doppler to “map” AR sample volume withdrawn towards apex sample volume withdrawn towards apex
to find length of regurgitant jetto find length of regurgitant jet Relies on turbulence during diastole on Relies on turbulence during diastole on
LV outflow side of AVLV outflow side of AV This assumes jet is centrally located This assumes jet is centrally located
and can be tracked towards apexand can be tracked towards apex Another possible source of error:Another possible source of error:
AR MS
•Presence of mitral stenosis or mechanical mitral valve
AR – Color FlowAR – Color Flow
Most common techniqueMost common technique Sensitivity >95%Sensitivity >95%
False positive negatives; occur in False positive negatives; occur in tachycardia with mild ARtachycardia with mild AR Frame rate allows only a few diastolic Frame rate allows only a few diastolic
frames to be displayedframes to be displayed Can be overcome by using CW which has Can be overcome by using CW which has
higher sampling ratehigher sampling rate
Specificity ~100%Specificity ~100%
AR – Color flow DopplerAR – Color flow Doppler
Detects even trivial ARDetects even trivial AR 1% of subjects under 40 y.o.1% of subjects under 40 y.o. 10-20% of patients greater than 60 y.o10-20% of patients greater than 60 y.o
Echo assessment: Vena Echo assessment: Vena ContractaContracta
Measurement of Measurement of the most narrow the most narrow portion of jet portion of jet behind the valve.behind the valve. Mild: <3.0mmMild: <3.0mm Moderate: 3.0-Moderate: 3.0-
5.9mm5.9mm Severe: Severe:
>=6.0mm>=6.0mm
Enriquez-Sarano et al. Aortic Regurgitation. NEJM; 351:1539-46.
Echo assessment: Jet / Echo assessment: Jet / LVOT heightLVOT height
Jet height to LVOT height Jet height to LVOT height ratioratio Mild: 1-24%Mild: 1-24% Moderate: 25-46%Moderate: 25-46% Moderate-severe: 47-Moderate-severe: 47-
64%64% Severe: >=65%Severe: >=65%
Limitations:Limitations: Lateral resolution of Lateral resolution of
color Dopplercolor Doppler Sensitive to angulation of Sensitive to angulation of
ultrasound transducerultrasound transducer
Ekery, DL et al. Aortic Regurgitation: Quantitative Methods by Echocardiography. Echocardiography: 2000. 17; 294-302
AR – Continuous wave AR – Continuous wave dopplerdoppler
Because AR jet is high velocity, CW Because AR jet is high velocity, CW Doppler necessary to record Doppler necessary to record envelope of jet.envelope of jet. The density of the jet compared with The density of the jet compared with
antegrade aortic flow is a (very simple) antegrade aortic flow is a (very simple) qualitative indication of the volume of qualitative indication of the volume of regurgitationregurgitation
Density is function of number of blood cells sampled Density is function of number of blood cells sampled and will generally increase with the regurgitant volumeand will generally increase with the regurgitant volume
Antegrade
AR
AR – Continuous wave AR – Continuous wave dopplerdoppler
AR – CW DopplerAR – CW Doppler
Aortic regurgitant fraction can be Aortic regurgitant fraction can be estimated by ratio of reversed flow VTI / estimated by ratio of reversed flow VTI / forward flow VTI in the distal aortic arch.forward flow VTI in the distal aortic arch.Ekery, DL et al. Aortic Regurgitation: Quantitative Methods by Echocardiography.
Echocardiography:2000. 17; 294-302
Antegrade
Retrograde
AR – Continuous wave AR – Continuous wave dopplerdoppler
Absolute gradient Absolute gradient does not closely does not closely reflect amount of ARreflect amount of AR
Severity of AR can be Severity of AR can be described by the described by the slope or the pressure slope or the pressure half timehalf time
Pressure half time of Pressure half time of less than 250 msec is less than 250 msec is an indicator of an indicator of severe ARsevere AR
AR - pressure half-timeAR - pressure half-time
Limitations:Limitations: Pressure half-time sensitive to chronicity of Pressure half-time sensitive to chronicity of
ARAR acute AR leads to much shorter values than acute AR leads to much shorter values than
chronic AR when ventricle is dilated with chronic AR when ventricle is dilated with increased compliance and can accommodate increased compliance and can accommodate large regurgitant volumes.large regurgitant volumes.
Pressure half-time varies with systemic Pressure half-time varies with systemic vascular resistancevascular resistance vasodilators may shorten the pressure half-time vasodilators may shorten the pressure half-time
even as the aortic regurgitant fraction improveseven as the aortic regurgitant fraction improves..
AR- Regurtitant volumeAR- Regurtitant volume
AR - Regurgitant Volume or AR - Regurgitant Volume or FractionFraction
Compare flow through aortic valve Compare flow through aortic valve versus mitral or pulmonary valve.versus mitral or pulmonary valve.
Regurgitant volume (fraction):Regurgitant volume (fraction): Mild: <30cc (<30%)Mild: <30cc (<30%) Mild to moderate: 30-44cc (30-39%)Mild to moderate: 30-44cc (30-39%) Moderately severe: 45-59cc (40-49)Moderately severe: 45-59cc (40-49) Severe: >=60cc (>=50%)Severe: >=60cc (>=50%)
Limitations:Limitations: Assumes normal flow through Assumes normal flow through
comparison valve.comparison valve. Cannot be used in presence of shunts.Cannot be used in presence of shunts. Sensitive to small measurement errors.Sensitive to small measurement errors.
AR - Regurgitant Volume AR - Regurgitant Volume or Fractionor Fraction
AR - Proximal isovelocity AR - Proximal isovelocity surface areasurface area
The PISA method can estimate The PISA method can estimate regurgitant flow rate, and regurgitant flow rate, and subsequently regurgitant orifice subsequently regurgitant orifice area).area).
AR - Proximal isovelocity AR - Proximal isovelocity surface areasurface area
Limitations of PISALimitations of PISA Isovelocity contour flattens as it Isovelocity contour flattens as it
approaches the orifice, underestimating approaches the orifice, underestimating flow.flow.
Proximal structures can distort the Proximal structures can distort the isovelocity contour.isovelocity contour.
Sensitive to errors in radius Sensitive to errors in radius measurementmeasurement 10% error in radius leads to 21% error in 10% error in radius leads to 21% error in
flowflow
SummarySummary
Severe AR - Surgical Severe AR - Surgical IndicationsIndications
Symptomatic patients (dyspnea or Symptomatic patients (dyspnea or angina)angina) Normal, mildly depressed or moderately Normal, mildly depressed or moderately
depressed LVdepressed LV Surgery.Surgery.
Severely depressed or dilated LV Severely depressed or dilated LV (EF<25% or LVESD>60mm)(EF<25% or LVESD>60mm) High surgical risk (~10% operative High surgical risk (~10% operative
mortality) but also poor outcomes with mortality) but also poor outcomes with medical therapy.medical therapy.
Asymptomatic Severe AR Asymptomatic Severe AR - Surgical Indications- Surgical Indications
Preserved LVPreserved LV Observe with serial echocardiograms.Observe with serial echocardiograms.
Abnormal LVAbnormal LV ““Rule of 55”: Surgery if:Rule of 55”: Surgery if:
LVEF <55% (ACC/AHA guidelines <50%)LVEF <55% (ACC/AHA guidelines <50%) LVESD > 55mm (or > 25 mm/m2).LVESD > 55mm (or > 25 mm/m2).
Also surgery if LVEDD >70-75 mmAlso surgery if LVEDD >70-75 mm Uncertainty on which combination of Uncertainty on which combination of
criteria most useful.criteria most useful.
AR – Surgical IndicationsAR – Surgical Indications