A
= A
* V
/V
2
1
1
2
hvor:
A
= aortaklapareal
2
A
= LVOT-areal (CSA)
1
V
= LVOT-hastighed (VMax)
1
V
= aortaventilhastighed (VMax)
2
LVOT = venstre ventrikels udløbsgang
Trykgradient (PGr) i mmHg
Oh, J.K., J.B. Seward, and A.J. Tajik. The Echo Manual. 3rd Edition, Philadelphia: Lippincott, Williams, and
Wilkins, (2007), p.63-66.
2
PGr = 4 * (hastighed)
Maks. E-trykgradient (E PG)
2
E PG = 4 * PE
Maks. A-trykgradient (A PG)
2
A PG = 4 * PA
Maks. trykgradient (PGmax)
2
PGmax = 4 * PV
Middeltrykgradient (PGmean)
Echocardiographic Assessment of Valve Stenosis: EAE/ASE Recommendations for Clinical Practice Journal
of American Society of Echocardiography, (January, 2009), 4-5.
PG-gennemsnit = sum(4v
hvor:
v = spidshastighed ved interval n
N = antallet af intervaller i Riemann-summen.
Qp/Qs
Oh, J.K., J.B. Seward, and A.J. Tajik. The Echo Manual. 3rd Edition, Boston: Philadelphia: Lippincott Williams
and Wilkins, (2007), p.70-72.
Qp/Qs = SV Qp-sted/SV Qs-sted = RVOT SV/LVOT SV
hvor:
RVOT SV = RVOT CSA* RVOT VTI = π/4 * RVOT-diameter
LVOT SV = LVOT CSA * LVOT VTI = π/4 * LVOT-diameter
Målereferencer
2
)/N
* RVOT VTI
2
* LVOT VTI
2
159