What Is the Echo Gold Standard to Measure

What Is the Echo Gold Standard to Measure Mitral Regurgitation ? Steven A. Goldstein MD FACC Director, Noninvasive Cardiology Medstar Heart Institute Washington Hospital Center Sunday, February 22, 2015

DISCLOSURE I have N O relevant financial relationships

Quantitation of Mitral Regurgitation • Echocardiography • Left ventriculography • CT-scan (CTA) • Cardiac MR (MRA)

American Society of Echocardiography Report Recommendations for Evaluation of the Severity of Native Valvular Regurgitation with Two-dimensional and Doppler Echocardiography Zoghbi, et al J Am Soc Echocardiogr 16: 777(2003)

Severity of Mitral Regurgitation Integrated Echo Assessment • Semiquantitation/qualitative § Color jet area § Signal intensity Antegrade flow (mitral E-wave) Pulmonary venous flow V-wave cutoff sign § § § • Quantitation: vena contracta width, PISA • Volumetric method (Regurg volume/fraction) • Indirect: LA and LV size

Parameters Used in Grading MR Severity Color Flow Jet Area Utility/Advantages Simple, quick screen for mild or severe central MR; evaluates spatial orientation of jet Limitations Subject to technical, hemodynamic variation; significantly underestimates severity in wall-hugging jets Zoghbi, et al J Am Soc Echocardiogr 16: 777(2003)

Mitral Regurgitation Qualitative Assessment courtesy of Jamil Tajik

Mitral Regurgitation Do Not Fall into Trap ! Color flow mapping is not an "ultrasonic angiogram" Color flow mapping is a velocity display and does not directly show volume information

Visualized Regurgitant Jet =/ Regurgitant Volume

Mitral Regurgitation Color Doppler Assessment Factors Affecting Regurgitant Jet Area 1. Regurgitant volume 2. 3. 4. 5. Velocity of regurgitation (driving pressure) Size and compliance of left atrium Central vs wall impinging jets Orifice size and shape 6. Influence of coexisting jets or flowstreams 7. Heart rate 8. Technical factors

Regurgitant Jets Technical Factors Affect Size, Shape, and Appearance • Gain settings, scale • Frame rate, sector size • Transducer • Color flow algorithms • Machine

Maximal Color Jet Area vs Angiographic Grade of MR 25 n. s. p<0. 05 Area (cm 2) 20 15 p<0. 05 10 5 0 p<0. 05 1+ 2+ 3+ Angiographic degree Fehske Am J Cardiol 73: 268(1994) 4+

Case

Correct settings Mild (1+) or mild-to-moderate (1 -2+)

Scale decreased Scale increased

Severity of Mitral Regurgitation Integrated Echo Assessment • Semiquantitation § Color jet area § Signal intensity Antegrade flow § § § Pulmonary venous flow V-wave cutoff sign • Quantitation: vena contracta width, PISA • Indirect: LA and LV size

Severity of Mitral Regurgitation Indirect Clues 2. 7 m/s Severe: E > 1. 5 m/s

Mitral Regurgitation Peak E-wave Velocity Retrospective study - Thomas JACC 31: 174(1998) Modest positive predictive value (75%) for an E-velocity >1. 2 m/s identifying patients with chronic severe MR E/A < 1 excludes severe MR

Severity of Mitral Regurgitation Integrated Echo Assessment • Semiquantitation § Color jet area Signal intensity Antegrade flow § Pulmonary venous flow § V-wave cutoff sign § § • Quantitation: vena contracta width, PISA • Indirect: LA and LV size

Mitral Regurgitation Pulmonary Venous Flow Pattern Normal Pattern Systolic Flow Reversal Systolic blunting < Severe MR Less predictive (trivial to severe)

Mitral Regurgitation Pulmonary Venous Flow Patterns Regurgitant Orifice Area (cm 2) 1. 8 1. 5 1. 2 0. 9 0. 6 0. 3 0 Normal Blunted Reversed Pu et al (Cleve Clinic) J Am Soc Echo 12: 736(1999)

Severity of Mitral Regurgitation Integrated Echo Assessment • Semiquantitation § § § Color jet area Signal intensity Antegrade flow Pulmonary venous flow V-wave cutoff sign • Quantitation: vena contracta width, PISA • Indirect: LA and LV size

Quantitation of MR - PISA Method

Proximal Isovelocity Surface Area (Flow Convergence) Hydrodynamic Principle As blood approaches a regurgitant orifice, its velocity increases forming concentric, roughly hemispheric shells of increasing velocity and decreasing surface area.

PISA Method Flow entering the proximal convergence zone V = 20 cm/sec V = 40 cm/sec V = 80 cm/sec = Flow exiting the regurgitant orifice V = 430 cm/sec Another form of the continuity equation

Conservation of Mass/Volume Va R Flowinto RA = Flowfrom RV A x Va = VTR 2 x Va Flow. TR = 6. 28 x R 2 x Valias

Quantitation of Regurgitation Criteria for Severe Regurgitation AR MR TR ERO R Vol (cm 2) (cm 3) 0. 3 0. 4 60 60 45

PISA - A Terrific Concept. . . but • Irregularly shaped regurgitant orifice (ROA) PISA shape may not be hemispheric • 3 D-imaging has shown that the ROA is often devoid of geometric assumptions • 3 D-PISA may be more accurate for EROA and regurgitant orifice • Remains to be seen if 3 D-PISA reproducible and useful in clinical setting

Chronic Mitral Regurgitation Shape of Regurgitant Orifice by MRI A C MS/Rheumatic Flail B D Buchner JACC Imaging 2011: 4; 1088 -96 Prolapse Functional

Chronic Mitral Regurgitation Shape of Regurgitant Orifice p<0. 01 Orifice Shape Index 7. 00 6. 00 p<0. 01 5. 00 4. 00 3. 00 2. 00 1. 00 Degenerative Prolapse Buchner JACC Imaging 2011: 4; 1088 -96 Flail Functional

Vena Contracta Width

Parameters Used in Grading MR Severity Vena Contracta • Narrowest portion of a jet • Occurs at or just downstream from orifice • High velocity, laminar flow • Slightly smaller than anatomic regurgitant orifice due to boundary effects • Represents a measure of the EROA Zoghbi, et al J Am Soc Echocardiogr 16: 777(2003)

Quantitation of Mitral Regurgitation Vena Contracta Imaging FCR MR jet Vena contracta: the small neck between the PISA region and the flair of the jet in the left atrium

Quantitation of Mitral Regurgitation Vena Contracta Imaging FCR Degree of MR Vena contracta width Mild Moderate Severe 0. 3 cm 0. 3 - 0. 6 cm >0. 6 cm MR jet MR

Parameters Used in Grading MR Severity Vena Contracta Width Utility/Advantages Simple, quantitative, good at identifying mild or severe MR Limitations Not useful for multiple MR jets; intermediate values require confirmation. Small values; thus, small error leads to large % error Zoghbi, et al J Am Soc Echocardiogr 16: 777(2003)

Volumetric Flow

Normal 70 m. L 70 L m

Mitral Regurgitation 120 m. L 50 0 7 L m (1) Mitral Reg Vol = Mitral SV - Aortic SV

Mitral Regurgitation 120 m. L 50 0 7 L m (1) Mitral Reg Vol = Mitral SV - Aortic SV (2) Reg Vol = SV Regurg Valve - SV Compet Valve

Severity of Mitral Regurgitation Integrated Echo Assessment • Semiquantitation § § § Color jet area Signal intensity Antegrade flow Pulmonary venous flow V-wave cutoff sign • Quantitation: vena contracta width, PISA • Indirect: LA and LV size

Parameters Used in Grading MR Severity LA and LV Size Utility/Advantages Enlargement sensitive for chronic significant MR, important for outcomes. Normal size virtually excludes significant chronic MR Limitations Enlargement seen in other conditions. May be normal in acute significant MR Zoghbi, et al J Am Soc Echocardiogr 16: 777(2003)

Summary

Conclusions • Accurate assessment of MR depends on integrating all these techniques. • All techniques have pitfalls and sources of error. • If there is doubt as to severity, TEE can be pursued.

MR Severity Assessment Color flow jet Mild Moderate Severe Central, small Central, moderate Vena contracta ≥ 0. 70 with large central jet or wall impinging jet of any size <4 cm 2 Vena contracta width (cm) Regurgitant volume (ml) fraction Orifice area (cm 2) <20% of LAA 20 -40% of LAA > 40% of LAA < 0. 30 -0. 69 ≥ 0. 70 < 30 < 0. 20 30 – 44 30 – 39 45 - 59 40 – 49 0. 20 – 0. 29 0. 30 – 0. 39 ≥ 60 ≥ 50 ≥ 0. 40 ASE Recommendations J Am Soc Echocardiogr 2003; 16: 777 -802