Table 4.

Echocardiographic parameters characterizing patients with heart failure (HF) symptoms and normal or preserved left ventricular ejection fraction (LVEF) in the combined right atrial (RA) and right ventricular (RV) phenotype

Echocardiographic parameter	Normal ranges—cut offs	Methodological aspects	Mandatory to determine (methods)	Why worth to do in routine
RV parameters
Enddiastolic RV free wall thickness (mm)	3–5 Cutoff < 5 [124]	Parasternal or subcostal short axis views of the RVOT can be used. Parasternal assessment is influenced by near field, subcostal assessment by far field	Yes	To detect or exclude RV hypertrophy Increased RV wall thickness indicates RV pressure overload
FAC (%)—fractional area change of the RV (assessed by RV focused 4ChV)	Cut off < 35 [115]	Estimation is error prone to individual RV topography in relation to LV in the 4ChV. FAC can only be interpreted if no or only mild TR is present	No—usually too error-prone, only if 3D acquisition is not possible	To estimate RV size and RV function
3D RVEDV—RV enddiastolic volume (ml)	♂ 98–141 Cut off > 98 ♀ 75–110 Cut off > 75 [125]	RV volumes should be measured by 3D echocardiography 2D parameters (areas, diameter) are too error prone due to improper standardization of the RV in respective sectional planes	Yes—if image quality is adequate	To estimate RVEDV—especially in abnormal RV geometry
3D RVESV—RV endsystolic volume (ml)	♂ 37–67 Cut off > 37 ♀ 27–49 Cut off > 27 [125]	RV volumes should be measured by 3D echocardiography 2D parameters (areas, diameter) are too error prone due to improper standardization of the RV in respective sectional planes	Yes—if image quality is adequate	To estimate RVEF and total RVSV
3D RVSVtot—total RV stroke volume (ml)	♂ 53–83 Cut off > 53 ♀ 42–67 cut off > 42 [125]	RV volumes should be measured by 3D echocardiography 2D parameters (areas, diameter) are too error prone due to improper standardization of the RV in respective sectional planes	Yes—if image quality is adequate	To estimate RVEF and total RVSV, which corresponds to effective RVSV, if PV and TV are normal
DRVOT (mm)—diameter of the right ventricular outflow tract (RVOT)	♂ 17—27 ♀ 17—27 [33]	3D imaging is preferred with respect to verifiable standardization. Diameter of the pulmonary trunk can be used as an alternative	Yes—under certain coditions	To estimate RVSVeff and cardiac output (CO)
Cardiac output (CO) determined by RVSVeff (effective RV stroke volume) using pulsed waved (pw) Doppler x heart rate (ml/l) - LVSVeff = 2 × DRVOT x VTIRVOT where VTIRVOT is velocity time integral of flow velocities determined in the right ventricular outflow tract	♂ 3.5–8.2 ♀ 3.3–7.3 [88]	Proper positioning of the pw sample volume in relation to the DRVOT is mandatory (if pulmonary trunc as an alternative is used, position of the sample volume must be adjusted—angulation of the cursor parallel to the blood stream is mandatory (subcostal imaging should be considered	Yes- under certain coditions	To estimate RVSVeff and CO To compare LVSVeff and RVSVeff
3D RVEF—RV ejection fraction (%)	♂ 54–59 Cut off > 54 ♀ 56–62 cut off > 56 [125]	RV volumes should be measured by 3D echocardiography 2D parameters (areas, diameter) are too error prone due to improper standardization of the RV in respective sectional planes	Yes—if image quality is adequate	To estimate normal or preserved LVEF
RVEDV/BSA (ml/m2)	♂ 55 – 68 Cut off > 55 ♀ 48—60 Cut off > 48 [125]	RV volumes should be measured by 3D echocardiography 2D parameters (areas, diameter) are too error prone due to improper standardization of the RV in respective sectional planes	Optional—by 3D volumetry	To adjust LV volumes in extreme conditions
RVESV/BSA (ml/m2)	♂ 22–32 Cut off > 22 ♀ 19–15 Cut off > 19 [125]	RV volumes should be measured by 3D echocardiography 2D parameters (areas, diameter) are too error prone due to improper standardization of the RV in respective sectional planes	Optional—by 3D volumetry	To adjust LV volumes in extreme conditions
TAPSE (mm)	♂ 17–29 cut off > 17 ♀ 17–27 Cut off > 17 [82, 84]	Assessment is possible by postprocessing of 2D cineloops of the 4ChV, not useful in TR and shunts	Optional—but helpful to detect subclinical states of cardiac diseases	To detect RV dysfunction in the presence of normal TV or only mild TR
RV free wall peak pw S ‘ velocity (cm/sec)	♂ 8—19 cut off > 8 ♀ 9—17 Cut off > 9 [110]	Acquire the pw tissue Doppler spectra using Duplex mode to control proper sample volume positioning of. Try to center the RV free wall for optimal image quality	Optional—but helpful in the normal and atrial phenotype	To estimate RV contractility
RV-IVRT = Free wall RV total isovolumetric relaxation time by pw tissue Doppler	0–36 Cut off ≤ 36 [123]	Acquire the pw tissue Doppler spectra with time speed of 100 mm/sec	Optional—but helpful in the normal and atrial phenotype	To estimate RV relaxation
TVI RV free wall strain (%)	27–31 Cut off > 17 [115]	Acquire three consecutive RR-intervals to detect artefacts and drifting	Optional—but helpful in the normal and atrial phenotype	To characterize longitudinal RV deformation
RV free wall GLS (%)	25–32 Cut off > 18 [16]	Ensure the full myocardial tracking of all RV myocardial layers	Optional—but helpful in the normal and atrial phenotype	To characterize longitudinal RV deformation
RIMP by pw RIMP = (TCO–ET)/ET -right index of myocardial performance	0.21–0.43 cut off < 0.43 [114, 115]	Acquire transpulmonic and transtricuspid pw Doppler spectra at the same heart rate to be comparable	Yes—especially in the RV phenotype	Increased RIMP indicates RV dysfunction and indicates reduced filling and ejection intervals
RIMP by TVI RIMP = (IVRT + IVCT)/ET	0.22–0.54 cut off > 0.54 [114, 115]	Acquire the pw tissue Doppler spectra with time speed of 100 mm/sec. The isovolumetric time intervals can only be determined with high temporal resolution	Yes—especially in the RV phenotype	Increased RIMP indicates RV dysfunction and indicates reduced filling and ejection intervals
VmaxTR–TR systolic peak velocity (m/sec)	Cut off ≤ 2.8 [114, 115]	VmaxTR only reflects RV pressure if pulmonary stenosis is excluded and if RV is not decompensated	Yes	To estimate RVESP
sPAP = 4 × VmaxTR2 plus estimated RAP (right atrial pressure)- estimated systolic pulmonary artery pressure (mmHg) -	Cut off ≤ 30 [114, 115]	RV pressures can only be estimated if pulmonary stenosis is excluded and if RV is not decompensated	Yes	To estimate RVESP
edVmaxPR—PR end-diastolic peak velocity (m/sec)	No normal ranges in the literature—if normal RVEDP-values of 10–15 mmHg are assumed, cut off < 1.2 [114, 115]	Acquire a transpulmonic cw Doppler spectrum for assessment	Yes—especially in the RV phenotype	To estimate RVEDP (= dPAP)
dPAP = 4 × edVmaxPR2 plus estimated RAP—estimated enddiastolic pulmonary artery pressure (mmHg)	No normal ranges in the literature, according to invasive assessment, normal dPAP < 10–15 mmHg [114, 115]	Acquire a transpulmonic cw Doppler spectrum for assessment	Yes—especially in the RV phenotype	To estimate RVEDP (= dPAP)
RAVImax (ml/m2)	♂: Cut off < 30 ♀: cut off > 28 [7]	Estimation is error prone to individual RA topography in the 4ChV	No—usually too error-prone, only if 3D acquisition is not possible	To estimate RA dysfunction and chronic RV diseases due to increased RV filling pressures
Collapse index inferior caval vein (%)	Cut off > 50 [115]	Ensure centering of the inferior caval vein (VCI) during longitudinal scanning. Biplane scanning should be preferred to document the VCI simultaneously in a short axis view	Yes	To estimate right atrial pressure (RAP) and systemic congestion. Decreased values indicate RAP increase
Pulmonary vascular resistance = PVR (msec−1) = (PEP/AcT)/(PEP +  RVET), where PEP is preejection period (= time interval between TR onset and onset of systolic pulmonary flow), AcT is time interval between onset and peak pulmonary flow, and RVET is right ventricular ejection time	Cut off < 2.5 [114]	This index estimates PVR and correlates with wood units (WU). The methodological advantage is the robustness of Doppler time intervals	Optional—especially in RV phenotype	To estimate PVR
PVR (cm−1) = (10 × VmaxTR)/VTIRVOT, where VTIRVOT is velocity time integral of flow velocities determined in the right ventricular outflow tract	Cut off < 2 [114]	This index estimate PVR and correlates with wood units (WU). Avoid methodological errors by acquiring the pw Doppler spectra. (adjust cursor and sample volume position)	Optional—especially in RV phenotype	To estimate PVR
PVR—(mmHg min cm−1) = sPAP/(heart rate x VTIRVOT)	Cut off > 0.076 [114]	This index estimates PVR. Increased index predicts severely increased PVR	Optional—especially in RV phenotype	To estimate PVR

For each echocardiographic parameter the normal ranges (and cut offs), methodological aspects, the importance of its determination, and the value to determine it in routine are listed. Mandatory parameters to be determined in clinical practice are labeled in bold print

RV right ventricular, FAC fractional area change of the RV, 4ChV 4-chamber view, RVEDV RV enddiastolic volume, RVESV RV endsystolic volume, RVSV_tot total RV stroke volume, RVOT right ventricular outflow tract, D_RVOT diameter of the RVOT, CO cardiac output, RVSV_eff effective RV stroke volume, VTI_RVOT velocity time integral of flow velocities determined in the RVOT, RVEF RV ejection fraction, BSA body surface area, TAPSE tricuspid annular plane systolic excursion, S´- maximum systolic tissue Doppler velocity of the myocardium near to the tricuspid anulus at the RV free wall, RV-IVRT free wall RV total isovolumetric relaxation, TVI tissue velocity imaging, RIMP right index of myocardial performance, TCO time interval between tricuspid valve closure and opening, ET ejection time, IVRT isovolumetric relaxation time, IVCT isovolumetric contraction time, TR tricuspid regurgitation, Vmax_TR TR systolic peak velocity, sPAP systolic pulmonary artery pressure, RAP right atrial pressure, PR pulmonary regurgitation, edVmax_PR PR end-diastolic peak velocity, dPAP enddiastolic pulmonary artery pressure, RAVI_max maximum RA volume indexed to BSA, VCI inferior caval vein, PVR pulmonary vascular resistance, PEP pre-ejection period, AcT time interval between onset and peak pulmonary flow, RVET RV ejection time, VTI_RVOT velocity time integral of flow velocities determined in the RVOT