Equations

MVA by PHT

MVA = 220/PHT

When is the simplified Bernoulli not valid?

What to use instead and what is that formula?

Proximal velocity >1.5m/s (ie LVOT for AS)

Valvular velocity <3m/s

Bernoulli equation

4 x (Vtransvalv - Vprox)²

When is LVOT velocity use in continuity equation not valid?

Subaortic flow acceleration

AR

Mean pulmonary artery pressure from PASP?

mPAP = (0.61 x PASP) + 2mmHg

MVA by deceleration time?

MVA = 759/DT

MVA by continuity equation?

MVA = Alvot * TVIlvot / TVImv

MVA by PISA

MVA = Qpisa / Vpeak

EROA for MR?

EROA = ((2 Pi r²) * Nyquist Limit) / Peak V of MR Jet

Surface area of PISA?

2 x Pi x r²

Blood flow at PISA?

Nyquist limit x (2 x Pi x r²)

How to calculate regurgitant volume in MR?

RV = EROAmr * VTImr

How to calculate shunt (Qp:Qs)?

TVIrvot x CSArvot / TVIlvot x CSAlvot

How to measure RSVP?

((Peak TR systolic velocity)² x 4) + RAP

Stroke Vol of LVOT from Area of LVOT and TVI LVOT

SVlvot = Arealvot * TVIlvot

How to calculate MV EROA?

MVRvol / TVImrjet

How to calculate MVRvol?

SVmv - SVlvot

How to calculate SVlvot?

CSAlvot x TVIlvot

How to calculate SV mitral valve?

220/MVpht x TVImv

Instant pressure gradient across valve?

Bernoulli

Pressure difference = 4v²

Continuity equation?

CSAlvot * VTIlvot = CSAav * VTIav

Regurgitant flow rate for PISA?

2 x pi x r² x aliasing velocity

EROA

Regurgitant flow rate / peak regurgitant velocity

Regurgitant volume from EROA?

EROA x VTIregurg

RAP from IVC?

Normal (IVC <2.1cm and >50% collapse) approx 3mmHg

Intermediate (RAP approx 8mmHg)

Dilated (IVC >2.1cm and <50% collapse) approx 15mmHg

Shunt calculation?

Normal value and significant L → R shunt

Qp:Qs

CSArvot * VTIrvot / CSAlvot x VTIlvot

Normal 1.0

Signif shunt >1.5

PASP from TR Jet?

4 x (TRvti)² + RAP

PADP from PR jet?

4 x (PRenddiastolicvti)² + RAP

Mean PAP?

4 x (PRearlypeakvti)² + RAP

Or

0.61 x PASP + 2mmHg