Table 1 Commonly used echocardiographic parameters used to assess RV function [18] and evidence of association in sepsis
Echo parameter | Measurement | Abnormal value | Use in assessing RV | Strengths and limitations | Comment | Evidence in sepsis |
|---|---|---|---|---|---|---|
RV Diameter | Measured at end diastole using focused apical four-chamber view | Basal > 4.2 cm Mid > 3.5 cm | RV dilatation: pressure or volume overload, often precedes RV dysfunction | Easy to perform | RV dilatation occurs in volume and pressure overload | Has not been shown to be predictive of mortality [8] |
RV FAC | Endocardial border is traced in end diastole and end systole EDA-ESA/EDA | <35% | Global systolic dysfunction, onerous to perform, difficult to be accurate | “Tedious” to perform [30] | Correlates well with RVEF | Associated with increased mortality [8] |
A4C TAPSE | Maximal excursion of tricuspid annulus in longitudinal plane. Measured with M-mode | < 1.6 cm | Utilises longitudinal systolic function as a marker of global RV function | Easy to acquire Low interoperator and intraoperator variability | Prognostic value in multiple disease states including PE, inferior MI, ARDS, critical illness [17, 19, 20] | TAPSE < 2.4 cm predictor of in hospital mortality and longer hospital length of stay [19] |
Tissue Doppler TV S′ | Apical motion measured using tissue doppler of the tricuspid annulus in systole | < 10 cm/s | Global systolic dysfunction | Easy to measure, reproducible | Correlates well with other measures of RV function | Reduced TV S′ associated with septic shock and increased mortality [3, 9] |
E/E′ | Ratio of pulsed doppler signal to tissue doppler signal in early diastole | < 6 | Elevated in diastolic dysfunction | Easy to perform. Multiple images and measures required | Not valid with significant TR | |
IVC | Diameter and respiratory collapse measured from the subcostal window | > 2 cm < 50% collapse = elevated RAP | Measures correlate with estimated RAP | Only possible from one window | > 2 cm < 50% collapse = elevated RAP < 2 cm < 50% collapse 8 mmHg < 2 cm > 50% collapse = RAP 3 mmHg | |
RA–RV pressure differential | Tricuspid regurgitant jet commonly used to calculate Peak systolic pulmonary artery pressures, RA pressures estimated from IVC size and variation | > 36 mmHg | Indicates raised pulmonary systolic pressure | Easy to perform. Multiple images and measures required | May be underestimated in right heart systolic dysfunction | |
MPI (Tissue Doppler) | Performed using tissue or conventional doppler (IVRT + IVCT)/SEP | > 0.55 | Assesses both systolic and diastolic function | Difficult to perform Not dependent on heart rate | May be underestimated in conditions that elevate RA pressures |