Table 2.

SABRE echocardiographic measures.

	Primary measures	Derived measures
LV structure	LV wall thickness, IVSd, and PWTd (PLAX) LV internal-diastolic dimension (PLAX) LV internal-systolic dimension (PLAX) LV end-diastolic volume (3D) LV end-systolic volume (3D) LV SV (3D) LV CO (3D) LV mass (3D)	LVEDV* (ml) = (0.7/2.4 + LVIDd) × LVIDd LVESV* (ml) = (0.7/2.4 + LVIDs) × LVIDs SV (ml) = LVEDV – LVESV and indexed to BSA SV index (ml/m2) = SV/BSA CO (ml/min) = SV × HR CO index (ml/min/m2) = SV × HR LV mass (g) = 0.8 × {1.04 [(LVIDd + PWTd + IVSd)3 – LVIDd3]} LV RWT = 2 × PWd/LVIDd
LV systolic function	Septal and lateral TDI S′ (A4C) Inferior TDI S′ (A2C) LV EF (3D) GLS (3D) GCS (3D) Twist and rotations (3D) Average segmental longitudinal, circumferential, radial, and principle tangential strain (3D)	Endocardial fractional shortening (%) = 100 × (LVIDd – LVIDs)/LVIDd Mid-wall fractional shortening = $\frac{(\text{lvidd}+\frac{\text{ivsd}}{2}+\frac{\text{pwtd}}{2})-\sqrt[3]{{(\text{lvidd}+\frac{\text{ivsd}}{2}+\frac{\text{pwtd}}{2})}^3-\text{ lvidd}+{\text{lvids}}^3}}{\text{lvidd}+\frac{\text{ivsd}}{2}+\frac{\text{pwtd}}{2}}$ LV EF (%) = 100 × (LVEDV – LVESV)/LVEDV
LV diastolic function	E wave, A wave, and deceleration time (A4C) Septal and lateral TDI e′ and a′ (A4C) Inferior TDI e′ and a′ (A2C)	E/A ratio = E wave/A wave e′/a′= TDI e′/TDI a′ E/e′ ratio = E wave/TDI e′ Peak untwisting rate, °/s
LV dyssynchrony		SDI volume−based (3D) (defined as the standard deviation of time to minimum segmental volumes over 16 LV segments) Strain-based systolic dyssynchrony indices (calculated as the standard deviation of time to peak segmental strain over 16 LV segments) volume- and strain-derived dispersion indices
LV-arterial interaction		Total peripheral resistance = mean arterial/CO Total peripheral compliance = SV/pulse pressure Pressure volume ratio = end-systolic pressure/LVESV Effective arterial elastance = end-systolic pressure/SV
LA structure & function	LA A-P dimension (PLAX)
Valvular function	Aortic Valve: AV peak velocity, and VTI (A5C)

^*Calculated by the Teichholz formula. A4C, apical four-chamber view; A2C, apical two-chamber view; A5C, apical 5-chamber; A-P, anteroposterior; AV, aortic valve; BSA, body surface area; CO, cardiac output; e′, peak early diastolic mitral annular velocity; EF, ejection fraction; GCS, global circumferential strain; GLS, global longitudinal strain; HR, heart rate; IVSd, interventricular septal diastolic wall thickness; LA, left atrial; LV, left ventricular; LVEDV, LV end-diastolic volume; LVESV, LV end-systolic volume; LVIDd, LV internal-diastolic dimension; LVIDs, LV internal-systolic dimension; PWTd, posterior diastolic wall thickness; PLAX, parasternal long-axis view; s′, peak systolic mitral annular velocity; RWT, relative wall thickness; SDI, systolic dyssynchrony index; SV, stroke volume; TDI, tissue Doppler imaging; VTI, velocity-time integral.