Transcription of Aortic Regurgitation: Etiology and Echo …
1 Aortic regurgitation : Etiology and echo QuantificationMartin G. Keane, MD, FASEP rofessor of MedicineLewis Katz School of Medicineat Temple University Review Question #1 Possible reasons that thiscolor Doppler evaluation mayoverestimate AR color Doppler gain of too small a color Doppler Nyquistvelocity pulse repetition frequency (PRF)Review Question #2 Which condition may lead to over-estimation of AR severity by deceleration slope (or P1/2) of diastolic Continuous Wave (CW) restrictive myocardial mitral valve Aortic valve Nyquistlimit settingReview Question #3 A continuous wave Doppler cursor is placed at the junction of the Aortic arch and proximaldescending aorta, just beyond the left subclavian artery. The following is obtained:Review Question #3 The Etiology of the diastolic Doppler flow indicated by the arrow of the left subclavian Aortic Aortic coarctation of the aortaAortic regurgitation : Etiology Valve Congenital (Bicuspid AV, SubaorticStenosis) Endocarditis Degenerative Traumatic Rheumatic Aortic Root Dilated Aortic root Marfan, Loeys-Dietz, Ehlers Danlos Hypertension Vasculitis Aortic Dissection The Aortic valve is the Root Cusps attached to root in coronet Sinuses and motion of root important for valve opening and competenceNCCRCCLCCS inotubularjunctionAnatomy of regurgitation .
2 Leaflet Malcoaptation Proximal Aortic dilatation Central regurgitation Leaflet thickening/retraction Rheumatic, degenerative Leaflet destruction Endocarditis, Trauma Leaflet prolapse Aortic dilatation / dissectionEtiology of Regurgitation: Bicuspid Aortic Valve Most common congenital AV abnormality Significant premature valve disease Aortic regurgitation in 40% Aortic Stenosis in 30% Etiology of Regurgitation: Degenerative / Rheumatic Degenerative Malcoaptation Calcific deformities of cusps and commissures Rheumatic Malcoaptation Thickening/retraction of cuspaledges and commissures Schaefer BM. Heart (2008) 94:1634-38; RosenhekR. NEJM (2000) 343:611 of Regurgitation: Proximal Aortic Dilatation Marfan, Loeys-Dietz, Ehlers-Danlos Non-syndromicaneurysms Chronic HypertensionEtiology of regurgitation : Aortic Dissection Retrograde extension past (proximal) ST junction Frequently associated with Rupture into pericardial space, coronary dissection Flap may prolapse into/through Aortic valveEtiology of Regurgitation: Leaflet Prolapse Myxomatous / Congenital Abnormality Loss of commissural support Partial tear of cusp (trauma) Best seen on PLAX or on TEE 120oEtiology of Regurgitation: Leaflet Destruction by EndocarditisPathophysiology.
3 Acute Aortic regurgitation Sudden, large regurgitant volume LVEDVM arked LVEDP Pulmonary Edema Decrease forward stroke volume Cardiogenic shock Urgent intervention required Nitroprusside/Inotropic agents Surgical RepairPathophysiology:Chronic Aortic regurgitation Primary Volume Overload Increased Preload (.. & Afterload!) Progressive ventricular dilation Chamber compliance increases Mild intracavitarypressure increase Myocardial hypertrophy Compensation for increased wall stress Maintains functionality of the ventricleLa Place s Law: T = (P*R)/MIncrease in Radius (R) Compensates for Volume OverloadTMMWall Thickness (M) also Increases, Normalizing Wall Stress (T)Chronic Aortic Regurgitation: Hypertrophy Process--R------R---Grossman W, et al.
4 J Clin Invest(1975) 56:56-64 Chronic Aortic regurgitation : Impaired myocardial function Slow increase in functionally abnormal myocytes Decreased coronary flow reserve Secondary to hypertrophy Patients become symptomatic at different levels of LV dysfunctionPROGRESSIVE MYOCARDIAL DYSFUNCTIONC hronic Aortic Regurgitation: Natural HistoryBonowRO, LakatosE, MaronBJ, Epstein S. Circulation1991, 84: 1625 1635 Chronic Aortic RegurgitationIndications for Surgery S y m p t o m s End-systolic LV dimension > cm Ejection fraction <50% Diastolic LV dimension > rapid progression/deterioration of indicesQuantitation of Aortic Regurgitation: Echocardiographic Approaches Qualitative Semi-Quantitative Guess-timating Regurgitant Orifice (Somewhat More) Quantitative Based on volumetric calculationsQuantitation of Aortic Regurgitation: Echocardiographic ApproachesZoghbi et al.
5 JASE (2003) 16 :Jet Width vs. LVOT Diameter Parasternal long axis TEE longitudinal plane<25% = mild25-64% = moderate 65% = severeAR / LVOT = 29%Moderate ARAR / LVOT = 73%Severe if??We segotsproblems:What we THINKwe are :Jet Width vs. LVOT diamMildModerateSevereMild ModerateModerate Severe<25%25 45%46 64% 65%Zoghbi et al. JASE (2003) 16 :Jet Width vs. LVOT diamMildModerateSevereMild ModerateModerate Severe<25%25 45%46 64% 65%Zoghbi et al. JASE (2003) 16 :-Measuring too far down in LVOT-Low Nyquistlimits-Excessive color Doppler gains-Eccentrically-directed jets-Eccentric origin of jets-Variation of flow (width)-Blood pressure dependentSemi-Quantitative:Jet Area vs. AoRoot AreaMildModerateSevereMild ModerateModerate Severe<5%5 20%21 59% 60%Zoghbi et al.
6 JASE (2003) 16 :Jet Area vs. AoRoot AreaMildModerateSevereMild ModerateModerate Severe<5%5 20%21 59% 60%Zoghbi et al. JASE (2003) 16 :-Measuring below the valve-Low Nyquistlimits-Excessive color Doppler gains-Multiple jets-Variation of flow (width)-Blood pressure dependentSemi-Quantitative:Vena ContractaMildModerateSevere< cm> cmZoghbi et al. JASE (2003) 16 :Vena ContractaMildModerateSevere< cm> cmZoghbi et al. JASE (2003) 16 :-Eccentric origin(non-circular)-Imprecision of measurement-Multiple Jets-Variation of flow (width)-Blood pressure dependentContinuous Wave DopplerSlope of Diastolic Spectral Envelope Decrease in Ao-LV pressure gradient Fall in velocity during diastole Flat slope = minimal diastolic gradient = mild ARContinuous Wave DopplerSlope of Diastolic Spectral Envelope Decrease in Ao-LV pressure gradient Fall in velocity during diastole Flat slope = minimal diastolic gradient = mild AR< m/sec2= mild> m/sec2= severeSemi-Quantitative:Diastolic CW Doppler SlopeAR jet MildModerateSevereDeceleration Slope(m/sec2)< 22 > Half-time(msec)> 500500-200< 200 Zoghbi et al.
7 JASE (2003) 16 :Diastolic CW Doppler SlopeAR jet MildModerateSevereDeceleration Slope(m/sec2)< 22 > Half-time(msec)> 500500-200< 200 Zoghbi et al. JASE (2003) 16 :-Poor (fuzzy)Doppler envelope-Some severe AR have long P -Low SVR decreases P -Severe MR decreases P -Restrictive filling decreases P Don t let this happen to you!!Qualitative Doppler:Desc. Aorta Flow ReversalMildModerateSevereBrief,Early DiastolicIntermediate,Early-MidDiastolicProminent,HolodiastolicZoghbi et al. JASE (2003) 16 Doppler for ARVolumetric Calculations Regurgitant volume SVLVOT SVRVOT {[ /4 * (LVOT diam)2]*VTILVOT} -{[ /4 * (RVOT diam)2]*VTIRVOT} Regurgitant Fraction RF = Regurgitant Volume / SVLVOT Effective Regurgitant Orifice Area EROA = Regurgitant volume/VTIARQ uantitative Doppler for ARVolumetric Calculations Benefits: Correlates well with CMR volumetrics Multiple jets no problem Spectral flow better than color Doppler Pitfalls: Use of mitral inflow requires too many assumptions Measuring RVOT flow and dimensions difficult Presence of AS confounds (LVOT acceleration) Inaccurate with >moderate MR or PR/PSQuantitative DopplerRegurgitant VolumeZoghbi et al.
8 JASE (2003) 16 ModerateModerate Severe<30 cc30 44 cc45 59 cc 60ccQuantitative DopplerRegurgitant FractionMildModerateSevereMild ModerateModerate Severe<30%30 39%40 49% 50%Zoghbi et al. JASE (2003) 16 DopplerRegurgitant Orifice AreaMildModerateSevereMild ModerateModerate Severe<10 mm210 19 mm220 29 mm2 30 mm2 Zoghbi et al. JASE (2003) 16 Doppler for ARPISA is PossibleSurface Areaalias* Velalias= EROAAR* VelAR[2 * ralias2] * Velalias= EROAAR* VelAR[2 * ralias2] * VelaliasVelARVAR(..but unlikely)Regurgitant volume = EROA * VTIARWHY DO WE CARE ABOUT THIS??Timing of Surgical InterventionAppropriate Patient Follow UpPassing echo Board ExamsAortic Regurgitation: Summary Progressive, asymptomatic disease Rate of progression varies individually Close clinical and echo follow up essential Medical treatment options are limited Symptoms indicate need for surgery Severity of AR and LV functional indices KEYparameters in asymptomatic patientsAortic Regurgitation: Summary An INTEGRATIVE approach is requiredZoghbi et al.
9 JASE (2003) 16 Question #1 Possible reasons that thiscolor Doppler evaluation mayoverestimate AR color Doppler gain of too small a color Doppler Nyquistvelocity pulse repetition frequency (PRF)Review Question #1 Answer: Possible reasons that thiscolor Doppler evaluation mayoverestimate AR color Doppler gain of too small a color Doppler Nyquistvelocity pulse repetition frequency (PRF)Review Question #2 Which condition may lead to over-estimation of AR severity by deceleration slope (or P1/2) of diastolic Continuous Wave (CW) restrictive myocardial mitral valve Aortic valve Nyquistlimit settingReview Question #2 Which condition may lead to over-estimation of AR severity by deceleration slope (or P1/2) of diastolic Continuous Wave (CW)
10 Restrictive myocardial mitral valve Aortic valve Nyquistlimit settingReview Question #3 A continuous wave Doppler cursor is placed at the junction of the Aortic arch and proximaldescending aorta, just beyond the left subclavian artery. The following is obtained:Review Question #3 The Etiology of the diastolic Doppler flow indicated by the arrow of the left subclavian Aortic Aortic coarctation of the aortaReview Question #3 The Etiology of the diastolic Doppler flow indicated by the arrow of the left subclavian Aortic Aortic coarctation of the aortaThank You!
