Aortic Regurgitation 2D and Doppler Assessment Dr.Sohail Abrar Khan MBBS,FCPS (Med), FCPS (Card) Diplomate of American certification Board of Echo Assistant Professor and Consultant Cardiologist Aga.
Download ReportTranscript Aortic Regurgitation 2D and Doppler Assessment Dr.Sohail Abrar Khan MBBS,FCPS (Med), FCPS (Card) Diplomate of American certification Board of Echo Assistant Professor and Consultant Cardiologist Aga.
Aortic Regurgitation
2D and Doppler Assessment Dr.Sohail Abrar Khan MBBS,FCPS (Med), FCPS (Card) Diplomate of American certification Board of Echo Assistant Professor and Consultant Cardiologist Aga Khan University Hospital Karachi
Introduction Aortic regurgitation is a common and serious health problem Echo is the most valuable tool in the diagnosis and management of AR Echo evaluation of AR requires a comprehensive evaluation by an experienced person Visual and qualitative assessment may be unreliable and misleading
Introduction
cont… Patients are often asymptomatic until AR becomes significant AR murmur usually not heard until AR severity > mild Detection of AR may be the first clue that aortic root or aortic valve disease is present
Role of Echo in Assessment AR
2D and Doppler echocardiography is indispensable in the diagnosis and management of patients with AR This should be used to assess the severity of AR, the LV response to volume overload (systolic function, ejection fraction [EF] and end-systolic and diastolic dimensions). Echocardiography may also identify the anatomic cause of AR, which is important for determining the surgical approach
Assessment of Regurgitation
2D Echo CFI Hemodynamics ERO/RV AR ERO/R Vol CW Doppler PW Doppler
Hemodynamics of AR
Chronic AR
Progressive ↑ AR Heart has time to compensate ↑ LV volume ↑ dilatation ↑ Stroke Volume
Acute AR
Rapid onset of AR Insufficient time for heart to compensate Leads to ↑ LVEDP Pulmonary edema Decreased effective forward Stroke vol
Hemodynamics of AR cont… Acute AR Chronic AR Adapted From: Lilly L. Pathophysiology of Heart Disease
Aortic Regurgitation
2D Echo
Assess valvular function Identification of functional anatomy Assess LV size and function Evidence of increased LVEDP
2D Echo
cont…
Assessment of LV
Serial reproducible findings LV chamber enlargement LV function assessment Predictors of preserved LV function after AVR LVESD < 55 mm LV EF > 50%
Conservative Rx for Severe AR Survival vs Indexed LV Systolic Diameter
100
89 ±3% LVS/BSA <25
80
81 ±5%
60
50 ±9% LVS/BSA 25
40
34 ±10%
20 0 0 Dujardin KS: Circ,99 2 4
Years
6 8 10 CP993609-9
Aortic Regurgitation
2-D and M-Mode
Clues of AR
Diastolic fluttering of anterior MV leaflet Reverse “doming” of anterior MV leaflet Diastolic flutter of aortic valve
Evidence for increased LVEDP
Presystolic (premature) closure of MV Presystolic (premature) opening of AV
Aortic Regurgitation Functional Anatomy
Valvular
Congenital (bicuspid) Degenerative Rheumatic Endocarditis Cusp rupture
Functional Anat
omy
cont…
Aortic Root
Chronic Dilatation Marfan syndrome Senile/hypertensive Chronic aortitis Idiopathic Annuloaortic ectasia Sinus of valsalva aneurysm Acute Disruption Dissection Chest trauma Endocarditis Post-procedure
Aortic Regurgitation
Color Flow Imaging Jet area
LVOT area Jet width
LVOT width
CP993609-12
Color Flow Imaging
cont… Jet Width/LVOT Width Perry et al. JACC 1987
Color Flow Imaging
cont… Jet area/LVOT area AR jet area and LVOT area from parasternal short axis view Correlates best with angiographic severity of AR Assess AR at the level of the aortic annulus, just below the AV Oh, Seward,Tajik: The Echo Manual
Color Flow Imaging
cont… Jet area/LVOT area Grade I Grade II Grade III Grade IV < 5% 5 - 24% 25 - 59% > 60%
Vena Contracta
Measure from PLAX (zoom) Use standard color scale No baseline shift Measure width of AR jet at the narrowest point Measure just below flow convergence Vena contracta < 6 mm = severe AR Vena contracta < 3 mm = mild AR
Vena Contracta
cont… VC Width 5 mm
6 mm
7 mm ERO≥0.3 cm 2 RegVol≥60 ml Sn 100 96 Sp 73 81 Sn 95 81 Sp 90 94 Sn 84 65 Sp 95 96 Tribouilloy et al: Circulation, 2000
Vena Contracta Optimize the flow convergence zone
Vena Contracta Measure width of AR at narrowest point of emitting jet Vena contracta is usually smaller than LVOT jet height
Aortic Regurgitation CW Doppler Assessment Density of CW signal reflects Reg Vol Pressure half-time Mild AR > 400 msec Severe AR < 250 msec Oh,Seward, Tajik: The Echo Manual
Align Doppler parallel to flow
Move lateral or try a lower rib space
CW Doppler Assessment cont… Pressure Half Time PHT Otto and Pearlman: Textbook of Clinical Echocardiography Mild AR > 400 msec
CW Doppler Assessment
cont… Pressure Half Time PHT Otto and Pearlman: Textbook of Clinical Echocardiography Severe AR < 250 msec
CW Doppler Ass
essment cont… AR PHT may be shortened due to other causes of elevated LVEDP i.e LV systolic and diastolic dysfunction and Mitral Regurgitation It can be increased due to Mitral Stenosis
Aortic Regurgitation PW Doppler Assessment LV stroke volume Mitral inflow Descending thoracic aorta Abdominal aorta
PW Doppler
cont…
Mitral Inflow
High LA Pressure & LVEDP Restrictive mitral inflow Mitral pattern dependent on compliance of ventricle Oh,Seward, Tajik: The Echo Manual
PW Doppler cont… Premature Cessation of Mitral Flow in Acute Severe AR Pre-op Post-op
PW Doppler
cont…
CP993609-21
PW Doppler
cont…
Descending Aorta
Diastolic flow reversal Retrograde flow TVI Severe AR TVI > 14 cm
PW Doppler
cont…
Abdominal Aorta
Place PW sample volume in abdominal aorta Diastolic flow reversal consistent with significant aortic regurgitation Otto and Pearlman: Textbook of Clinical Echocardiography
Indications for Quantitative Doppler When regurgitation appears moderate or more by CFI/qualitative assessment Serial assessment Assess LV size & function Assess regurgitation Assist clinician/surgeon Clinical management Timing of surgery
Quantitative Doppler Methods CSA TVI
Continuity Equation PISA Method
Continuity Equation Stroke volume Valve area Shunt lesions Regurgitant volume Regurgitant fraction
Continuity Equation
cont…
What goes in
(the ventricle)
must go out!!
Regurgitant Volume Volume of blood that regurgitates through an incompetent valve with each heart beat
Continuity Equation Calculation
Stroke volume = A Area X TVI TVI CP944143- 6
Continuity Method
cont…
“What goes in must go out”
Measurements required LVOT diameter & TVI MV annulus diameter & TVI Limitation of continuity method Unable to use with multiple regurgitant lesions > mild and shunt lesions
Continuity Method
cont…
Calculate SV LVOT
Measure LVOT diameter Obtain PW Doppler signal in LVOT Trace LVOT TVI SV LVOT = CSA LVOT x TVI LVOT
Continuity Method cont…
Calculate SV MV
Measure diameter of mitral annulus Obtain PW Doppler signal at level of mitral annulus Trace MV annulus TVI SV MV = CSA MV x TVI MV
Regurgitant Volume and Fraction SV LVOT = CSA LVOT x TVI LVOT SV MV = CSA MV x TVI MV RV AR = SV LVOT - SV MV RF AR = RV AR / SV LVOT
Pitfalls of Continuity Method Learning curve of the operator Incorrect placement of sample volume Incorrect annulus measurement Requires 4 separate measurements Introduces 4 possible errors Diameters are squared in the equation so any small error will be magnified and spoil the result Invalid with multivalvular regurgitation or intracardiac shunts
PISA
P
roximal
I
sovelocity
S
urface
A
rea
Advantages of PISA Method Can be used in the presence of other valvular regurgitation or shunts Can be used in the presence of valve stenosis or prosthetic valves Uses fewer variables (2 measurements)
PISA Method Shift color baseline in the direction of flow Alias velocity varies (range of 20-40 cm) Note alias velocity Adapted from Oh, et. al.
AR Peak Velocity and VTI Using CW Doppler, obtain optimal regurgitant jet Use alternate windows to be parallel to flow Measure peak regurgitant velocity Trace regurgitant TVI
PISA Calculations
Flow (cc/sec)
= 6.28 x [r (cm)] 2 x V a (cm/sec)
ERO (cm 2 )
= Flow (cc/sec) V (cm/sec)
RV (cc)
= ERO (cm 2 ) x TVI (cm)
E ffective R egurgitant O rifice Size of orifice through which regurgitation passes Also referred to as ROA (regurgitant orifice area)
Pitfalls of PISA Method
Learning curve of operator Assumption of hemispherical flow convergence area Inability to accurately measure radius Inability to obtain complete MR jet by CW Doppler
Jet/LVOT area Jet/LVOT Width Vena Contracta CW Doppler AR PHT Descending Aorta Reversal TVI
Severity of AR
Mild
<2 5%
Severe
> 60% < 25% > 60% < 3 mm > 6 mm faint > 400 msec early diastolic > 14 cm dense < 250 msec holodiastolic
Summary Aortic regurgitation is a common and serious health problem Echo is the most valuable tool in the diagnosis and management of AR Echo evaluation of AR is complex and often suboptimal Visual and qualitative assessment is is often misleading It is now very reliable by the use of quantitative methods An organized and comprehensive approach by using all the available qualitative and quantitative methods is required for proper assessment of AR