Table 2.

Simple parameters and indices obtainable by bedside limited transthoracic echocardiography for assessment of the right heart in patients with high resistance in the pulmonary circulation [56, 63, 68, 70, 77, 81, 82, 85, 86, 88, 91]

Parameters and indices	RV dysfunction due to high resistance in the pulmonary circulation	Preserved RV contractile function	Reduced RV contractile function
RVEDD, RVEDA	• Increased	• No specific change*	• No specific change*
S/L RV axis ratio	• Increased (> 0.57)	• No specific change*	• No specific change*
RA size	• Increased	• No specific change*	• No specific change*
Atrial septum	• Shift to left	• No specific change*	• No specific change*
TR	• New appearance or aggravation of preexistent TR	• No specific change*	• No specific change*
Ventricular septum	• Shift to left	• No specific change*	• No specific change*
RVEDD/LVEDD	• Increased (> 0.65 up to ≥ 1.0)	• No specific change*	• No specific change*
FACRV	• Reduced (< 0.35%)	• No specific change*	• No specific change*
TAPSE	• Reduced (< 1.6 mm)	• No specific change*	• No specific change*
SV	• Progressive reduction	• Reduced only at excessively high afterload	• Reduced already at moderate afterload increase
∆PRV-RA**	• Initially progressive increase, then progressive reduction to low values	• Increased (> 35 mmHg)	• Reduced (no defined cut-off value)
FACRV/RVSP and TAPSE/RVSP (RV-PA coupling)	• Reduced (FACRV/RVSP < 1; TAPSE/RVSP < 0.635) The initial decrease is mainly due to the RVSP increase, followed by further decrease also due to SV reduction Later, despite the additional reduction of myocardial contractility both FACRV and TAPSE reduction can be counterbalanced by the increasing TR which reduces the diagnostic relevance of the ratios	• Reduction is likely in patients with only mild to moderately reduced FACRV and/or TAPSE in the presence of excessively high RVSP	• Reduced in patients with relevantly reduced FACRV and/or TAPSE in the presence of only moderately increased RVSP
LAIRVa	• Initially progressive increase (preserved adaptability to load), then progressive reduction to low values (afterload mismatch)	• High (> 18)	• Low (< 15) indicates the necessity for temporary mechanical RV support

ECHO echocardiography; RV right ventricle; RVEDD and RVEDA RV end-diastolic diameter and end-diastolic area, respectively; S/L short/long axis ratio; SV stroke volume; RA right atrium; TR tricuspid regurgitation; LVEDD left ventricular end-diastolic diameter; FAC_RV fractional area change; TAPSE tricuspid annulus peak systolic excursion; ∆P_RV-RA pressure gradient between RV and RA during systole; RVSP RV systolic pressure; RV-PA right ventricular-pulmonary artery; LAI_RV RV load adaptation index

*Parameter alteration indicates RV alteration which could be caused by both high afterload and decreased myocardial contractility (etiopathogenetic differentiation not possible)

**Useful for differentiation between patients with and without reduced RV contractile function

^aThe LAI_RV can be useful to predict therapy-refractory RVF in both pre- and post-capillary PH