Echo of Mitral Stenosis Severity and Important Echo

Echo of Mitral Stenosis Severity and Important Echo Features 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

Mitral Stenosis Morphology • Leaflet thickening and calcification • Commissural fusion • Commissural and leaflet calcification • Chordal thickening, shortening & fusion

Pre-PTMV Post-PTMV

Scan off-axis to evaluate subvalve apparatus

Severity of Mitral Stenosis Echo-Doppler is method of choice

Mitral Stenosis Quantitation by Echo-Doppler • Transvalvular gradients (Peak, mean , end-diastolic) • Mitral valve area § § Planimetry Pressure half-time method Continuity equation PISA method • Pulmonary artery pressure

Gradients

Mitral Stenosis Doppler-Derived Gradients • Unlike AS, technically easy in MS • Reliable gradient almost always obtained with transducer at apex • In rare instance of extremely difficult apical window, TEE can be used

Mean PG 23. 9 mm Hg VTI 94 cm Vmax 320 cm/s Mean gradient = 24 mm Hg

18 mm Hg 13 mm Hg In atrial fib average ≥ 5 consecutive beats

Mitral Stenosis Pitfalls of Doppler Evaluation Pressure Gradient • Intercept angle b/w MS jet and echo-beam • Beat-to-beat variability in atrial fibrillation • Dependence on transvalve flow rate (depends on current HR, CO, MR) Always report HR ! (variable)

MV Area

MV Area by Planimetry Advantages: Ease of use Pathologic correlation Unaffected by MR and AR Limitations: May not image true orifice Gain and angulation Calcification Prior commissurotomy

Pressure Halftime

Atrioventricular Pressure Half-Time Measurement of Mitral Orifice Area Libanoff and Rodbard Circ 38: 144(1968)

Mitral Valve Area Doppler Pressure Halftime Hatle (1979) showed that MV area could be estimated as. . 220 Doppler-derived mitral pressure halftime

MV Area Continuity Equation

Mitral Valve Area Continuity Equation MV Area = CSA LVOT x VTILVOT VTI MS JET

MV Area PISA

r = 1. 2 cm Va = 30. 8 cm/s

Mitral Valve Area: PISA Method Standard PISA Equation Assumption Orifice is planar Mitral Stenosis Correction Orifice is NOT planar Orifice is Funnel-shaped PISA Flow Rate Orifice Area (cm 2) = (cm 3/sec) Vmax (cm/sec) x Angle 0/180º Average 0 = 118 ± 15º Circulation 1993; 88: 1157 -65

3 D-Echo likely the new “Gold Standard” Post-PTMV Pre-PTMV

A 1 = 0. 80 cm 2 TTE MV area = 0. 80 cm 2

“Splittability” Score

Mitral Stenosis “Splittability” Score (MGH Score) (grade 1 – 4) • Leaflet thickening • Leaflet mobility • Leaflet calcification • Subvalvular fusion Score < 8 = excellent candidate for PBMV

Mitral Stenosis "Splittability Score" I. Leaflet mobility II. Leaflet thickening III. Leaflet calcification IV. Subvalve thickening & fusion • Appearance of commissures

Mitral Valvuloplasty The mechanism of successful PBMV is opening of commissures RV RV

Freedom from Death, MVR, repeat PBMV (%) Mitral Balloon Valvotomy and Outcome 100 MV score 8 80 80 MV score >8 60 60 40 40 20 20 0 Ca++absent 0 0. 5 1 1. 5 2 2. 5 Years from Procedure 3 0 0 Ca++present 0. 5 1 1. 5 2 2. 5 Years from Procedure Cannan, Nishimura, et al JACC 29: 175(1997) 3

Mitral Valvuloplasty Commissural Calcium RV RV

Mitral Stenosis “Splittability” Score (MGH Score) Limitations • Subjective (High interobserver variability) • Inability to describe localized changes • Some pts with score > 10 successful PBMV • Some pts with score < 8 have complications