Ηλίας Κ.Καραµπίνος Δ/ντης Καρδιολογικής Κλινικής ΕΥΡΩΚΛΙΝΙΚΗ

Ελληνική Καρδιολογική Εταιρεία 4ο Επιµορφωτικό Σεµινάριο Ειδικευοµένων 2011-2012 Γραφεία ΕΚΕ: 6-7 Απριλίου 2012 Πως θα αντιµετωπίσω τον ασθενή µε Μικρού/µετρίου βαθµού στένωση της αορτής και δυσλειτουργία της αρ κοιλίας? Ηλίας Κ.Καραµπίνος Δ/ντης Καρδιολογικής Κλινικής ΕΥΡΩΚΛΙΝΙΚΗ

Aortic Stenosis: pathophysiology

Pressure volume curve in aortic stenosis

Relation between LV end systolic wall stress @ circumferential velocity of fiber shortening in aortic stenosis Colan et al. JACC 1984

LV dysfunction in AS is usually due to... Afterload mismatch Longstanding severe AS myocardial fibrosis concurrent severe coronary artery disease prior myocardial infarction DCM, mitral valve regurgitation, etc

a stiff valve that cannot open or an unresponsive myocardium?

Low flow Low gradient Aortic Stenosis: True severe vs Pseudo severe AS

Low flow Low gradient Aortic Stenosis Carabello et al, Circulation 1980: 14 pts with no CAD,AS and HF If MG<30 mmhg very bad prognosis Brogan et al. JACC 1993 : 18 pts with AS and HF and MG<30 mmhg 33% in hospital mortality, very bad longer prognosis Connoly et al Circulation 1997 : 29 pts with AS and HF and MG<30 mmhg 24% in hospital mortality, 60% 5 year mort Blitz et al. AJC 1998 52 pts with AS and HF and MG<30 mmhg 11% in hospital mortality, 38% 5 year mort

In this case, there is no diagnostic issue

But in these cases, which are not rare.?

Grading aortic stenosis with normal left ventricular systolic function Severe aortic stenosis: definition ACC/AHA, and ESC

WHAT IS LOW GRADIENT, LOW FLOW AORTIC STENOSIS? Effective orifice area < 1.0 cm2 LV ejection fraction <40% Mean pressure difference < 30 or 40 mm Hg

Low flow Low gradient Aortic Stenosis 19% of pts for AVR have some LV dysfunction

Estimation of aortic stenosis severity Transvalvular Gradient Aortic valve Area Aortic Resistance

Flow dependence an important issue regarding AS severity estimation Flow, AV area and Gradient: interrelated variables Flow Gradient AVA

Gradient vs Flow

Aortic Valve Area vs Flow

Valve area vs pressure gradient: inconsistency of findings Minners et al EHJ 2007

1 st STEP Estimation of aortic stenosis severity Transvalvular Gradient Aortic valve Area Aortic Resistance

2 nd STEP Calculation of EOA Calculation of effective orifice area is essential whenever a thickened, immobile aortic valve is associated with a reduced LV ejection fraction. The transaortic velocity and derived pressure difference are flow-dependent while effective orifice area by the continuity equation is relatively flowindependent

Anatomic vs functional valve area Anatomic valve area: maximal mid-end systolic area in a precise moment Effective valve area: pansystolic functional area averaged throughout the complete ejection period Effective orifice underestimates true orifice area? De Grof et al. Circulation 1998

Gorlin s Formula Torricelli s principle : laminar flow

F= c.a.v A=F/c.V and V=k. 2g P A=F/C. 1960 P = F/44.3 C P A=CO/44.3 C HR. SEP P Overestimates the stenosis in low CO Underestimates the stenosis in high CO

Low flow Low gradient Aortic Stenosis: The continuity equation The continuity equation is based on the law of conservation of mass. In a closed system, the stroke volume below the valve must be the same as the stroke volume through the valve. how to assess

Erroneous quantification of doppler derived-ava due to septal hypertrophy Skjaerpe et al. Circulation 1985 Poh, K. K. et al. Eur Heart J 2008

3 rd STEP Do not forget planimetry with TTE if it is possible, otherwise with TOE

Flow-Dependent Changes in Doppler-Derived Aortic Valve Effective Orifice Area Are Real and Not Due to Artifact Kadem et al, JACC 2006:47;131-137

Effects of variations in flow on aortic valve area in aortic stenosis based on in vivo planimetry of aortic valve area by multiplane transesophageal echocardiography Tardif et al. AJC 1995

Methods: 21 pts During surgery TEE Infusion of saline or inotropic agents Results: AVA = 0.25-1.4 cm 2 Group I : 11 pts SV AVA change 0.001cm 2 Group II : 14 pts SV AVA change 0.002cm 2 Tardif et al. AJC 1995

Acute changes in stroke volume and cardiac output do not result in significant alterations in the anatomic AVA measured With TEE in pts with AS of moderate or severe degree Tardif et al. AJC 1995

JACC 1997

However AVA planimetry is not always very easy and accurate

The role of TOE ACC/AHA Guidelines 2006 Bonow et al

The role of 3-D echocardiography in AS

Assessment of aortic stenosis by 3D Goland et al, Heart 2007

4 th STEP Think of other echo methods.

Low Flow Low Gradient Aortic Stenosis: how to assess Waveform shape The continuous wave signal in patients with moderate aortic stenosis has a relatively fast upstroke and the mean gradient is approximately half the peak. In patients with severe stenosis, the ejection time and the time to peak velocity are both prolonged and the mean gradient is approximately two thirds the peak.

Low flow Low gradient Aortic Stenosis: how to assess The peak to mean pressure gradient ratio: a new method of assessing aortic stenosis ROC analysis showed that a ratio <1.50 gave a specificity of 94% whereas < 1.75 gave a sensitivity of 96% Τhe aortic stenosis is always severe if the peak divided by the mean pressure difference is < 1.5 and dobutamine stress should be performed to clarify the diagnosis if the ratio is < 1.7. Chambers et al JASE 2005

Low flow Low gradient Aortic Stenosis: how to assess Measures based on systolic ejection time: Relative ejection time Expected ejection time (in seconds) is 0.002 stroke volume (in ml) + 0.106 An ET difference of greater than or equal to 0.060 second was 88% sensitive, 89% specific, and 89% accurate for detecting critical aortic stenosis Zogbi et al. Am Heart J 1988 If the observed ejection time is more than 0.07 s longer than expected from the left ventricular ejection fraction, it is likely that the aortic stenosis is severe Chambers et al Heart 2006

Low flow Low gradient Aortic Stenosis: how to assess Measures based on systolic ejection time: The Tei index IVRT + ICT + EJT)/EJT Receiver operating characteristic curve analysis for the Tei index yielded an area under the curve of 0.98 +/- 0.03 for separating severe AS pts with low EF. Tei index > 0.42 was identified with a sensitivity of 100% and a specificity of 91%. Bruch et al JASE 2002

Hemodynamic resistance as a measure of Functional impairment in aortic valvular stenosis Ford et al. Circ Res. 1990

Canon et al. JACC 1992 After nitroprusside infusion

JACC 1994

5 th STEP Dobutamine stress echocardiography to determine AS severity

USEFULNESS OF DSE IN DISTINGUISHING SEVERE FROM NON SEVERE VALVULAR AORTIC STENOSIS IN PATIENTS WITH DEPRESSED LEFT VENTRICULAR FUNCTION AND LOW TRANSVALVULAR GRADIENTS defilippi et al.ajc 1995

18 pts with EF<45%, mean grad<30mmhg, AVA<0.5 cm 2 /m 2 continuity equation Group IA: WMS>20%, increase AVA<0.3 cm 2, mean grad>10mmhg, AVR increase Group IB: WMS>20%, increase AVA>0.3 cm 2, mean grad<10mmhg, AVR increase Group II: WMS<20%, defillipi et al. AJC 1995

CONTRACTILE RESERVE YES NO AVA <0.3 cm 2, mean grad>10mmhg FIXED AS AVA >0.3 cm 2, mean grad<10mmhg RELATIVE AS

Dobutamine Stress Echo in low flow AS: practical rules In general, severe aortic stenosis is associated with a relatively large rise in mean pressure difference and a relatively small rise in orifice area. By contrast, moderate stenosis is associated with a small rise in mean pressure difference and a larger rise in effective orifice area. Severe stenosis is suggested by a failure of the effective orifice area to increase above 1.2 cm2 A simpler practical guide is a rise in the mean pressure difference above 30 mm Hg at any time during dobutamine infusion

Low Gradient AS and Low Ejection fraction: the role of dobutamine stress echo Assessment of contractile reserve + Good prognosis - Bad prognosis DSE Severe AS: increase <0,3cm2 and total AVA <1cm2 Relative AS: increase >0,3cm2 and total AVA > 1cm 2 Drugs, follow up AVR

78years old male with MV prosthesis and dyspnea. Baseline study

Dobutamine stress echo 20mcg/kgr/min

5 th STEP Dobutamine stress echocardiography to predict?

Low flow Low gradient Aortic Stenosis: the role of CR

Low flow Low gradient Aortic Stenosis: CR for prediction of postop LVEF? Postop. LVEF is not related to presence of CR Quere et al Circulation 2006

Low flow Low gradient Aortic Stenosis: CR For deciding about Surgery or Medical treatment?

Low flow Low gradient Aortic Stenosis: CR for deciding about Surgery or Medical treatment?

Low flow Low gradient Aortic Stenosis: CR for prognosis?

Surgical treatment for Pts without CR: a matter of risk

Low flow Low gradient Aortic Stenosis: Prognosis of pts without CR Operative mortality 22%

6 th STEP Estimate the surgical risk

Low flow Low gradient Aortic Stenosis: What is the surgical risk?

Operative Risk the main determinants

Low flow Low gradient Aortic Stenosis: What is the surgical risk over time?

Low flow Low gradient Aortic Stenosis: Predictors of mortality Levy et al JACC 2002

Combined impact of PPM and LV dysfunction on operative mortality

What do the guidelines say?

ACC/AHA 2006 Guidelines for the Management of Patients With Aortic Stenosis Class I 1. AVR is indicated for symptomatic patients with severe AS.* (Level of Evidence: B) 2. AVR is indicated for patients with severe AS* undergoing coronary artery bypass graft surgery (CABG). (Level of Evidence: C) 3. AVR is indicated for patients with severe AS* undergoing surgery on the aorta or other heart valves. (Level of Evidence: C) 4. AVR is recommended for patients with severe AS* and LV systolic dysfunction (ejection fraction less than 0.50). (Level of Evidence: C) Class IIa AVR is reasonable for patients with moderate AS* undergoing CABG or surgery on the aorta or other heart valves (see Section 3.7 on combined multiple valve disease and Section 10.4 on AVR in patients undergoing CABG). (Level of Evidence: B) Bonow et al, Journal of the American College of Cardiology 2006

ACC/AHA 2006 Guidelines for the Management of Patients With Aortic Stenosis Bonow et al, Journal of the American College of Cardiology 2006

ESC 2007 Guidelines for the Management of Patients With Aortic Stenosis Vahanian et al, Eur Heart J 2007

Πως θα αντιµετωπίσω τον ασθενή µε Μικρού/µετρίου βαθµού στένωση της αορτής και δυσλειτουργία της αρ κοιλίας? Θα ξεκινησω µε διαθωρακική ηχωκαρδιογραφία: mean gradient (cut off 40 mmhg) και ΕΟΑ µε εξίσωση συνεχείας Θα αποφασίσω an η στένωση είναι σοβαρή και µε πλανιµέτρηση ίσως και µε ΤΟΕ Stress Echo για να καθορίσουµε αν η στένωση είναι σοβαρή (cut offs 0,3 cm2, <1,2 cm2, mean G 10 mmhg, PG 40mmHg) και αν υπάρχει συστολική εφεδρεία (SV ή VTI >20%) Αν δεν υπάρχει εφεδρεία θα σκεφθώ και την MSCT

Πως θα αντιµετωπίσω τον ασθενή µε Μικρού/µετρίου βαθµού στένωση της αορτής και δυσλειτουργία της αρ κοιλίας? Αν δεν υπάρχει εφεδρεία και η στένωση είναι σοβαρή δεν θα τον αποκλείσω από το χειρουργείο Η συστολική εφεδρεία δεν προβλέπει την απώτερη πρόγνωση του ασθενούς ΑΝΕΞΑΡΤΗΤΑ, ούτε το µετεγχειρητικό κλάσµα εξώθησης Θα εκτιµήσω τον εγχειρητικό κίνδυνο. Το mean gradient, η παρουσία στεφανιαίας νόσου, και το EUROSCORE αποτελούν ανεξάρτητους παράγοντες πρόγνωσης

ευχαριστώ Ανδρίτσαινα-χωριό Κάρµι, Ορεινή Ολυµπία 2008

Pseudo-severe AS: prevalence and outcome

Pseudo-severe AS pts under conservative treatment

Clinical relevance of Pseudosevere AS: TOPAS study Clavel et al Circulation 2008

Pseudo-severe AS pts under conservative treatment

JACC 1998

Flow dependence may contribute to pathophysiologic and clinical variability in pts with severe AS Slope of flow dependence a (AVA/ flow): a new index for assesing the functional significance of AS Shively et al. JACC 1998