Table 1 Summary of echocardiographic variables that have been used to evaluate septic cardiomyopathy
| Â | Echo parameter | Measurement | Significant findings | Strengths | Limitations | Comments |
|---|---|---|---|---|---|---|
Left ventricle | Â | Â | Â | Â | Â | Â |
Systolic | EF | EF = (LVEDV − LVESV)/LVEDV × 100 | Abnormal LV systolic function suggested by EF < 52% in men or < 54% in women [63] | Frequently used; easy to acquire | Biplane Simpson’s Method of Discs is the only currently recognized method per ASE guidelines. Requires adequate image quality; EF will vary with beat to beat variation; highly dependent on loading conditions of the LV | Familiar to all clinicians. Fails to accurately identify all patients with SC |
GLS | GLS (%) = (MLs − MLd)/MLd | Abnormal LV systolic function suggested by peak GLS < − 20% [63] | Improved prognostication over LVEF for determining LV systolic function; independent of angle | Requires adequate image quality, absence of foreshortening, and three standard apical views. No consensus on abnormal values due to variability in vendors and analytic software | Speckle-tracking technology increasingly available | |
Systolic mitral annular velocity (S′) | AVG peak systolic velocity (cm/s) of the mitral annulus is measured using spectral TDI | No current consensus recommendations on abnormal values; abnormal LV systolic function suggested by decreased S′ < 10 cm/s | Easy to acquire; less dependent on preload | Not well validated; heterogeneity of values depending on patient age; may be affected by regional wall motion abnormalities, annular calcifications, and prosthetic valves | Able to be performed with old or modern equipment | |
MAPSE | MAX systolic plane excursion of the lateral mitral annulus (cm) is measured using M-mode | No current consensus recommendations on abnormal values; abnormal LV systolic function suggested by decreased MAPSE < 1 cm | Easy to acquire | Requires adequate M-mode cross section; may be affected by regional wall motion abnormalities, annular calcifications, and prosthetic valves | Conceptually similar to GLS, but able to be performed without speckle-tracking or Doppler | |
MPI | MPI = (TST − ET)/ET | Abnormal LV function suggested by MPI > 0.40 [78] | Derived from simple time interval recordings; less load dependency; does not rely on geometric assumptions | Limited validated research; both systolic and diastolic dysfunction can result in an abnormal MPI; requires accurate measurements of cardiac time intervals | Most clinicians have little familiarity with this measure | |
Diastolica | e’ | Peak e’ velocity (cm/s) in early diastole measured using PW Doppler at lateral and septal basal regions and then averaged | Abnormal LV diastolic function suggested by e’ (septum) < 7 cm/s or e’ (lateral) < 10 cm/s [51] | Easy to acquire; less dependent on preload | Regional wall motion abnormalities and CAD will affect the measurement; heterogeneity of values depending on patient age | Highly studied and shows promise as a simplified method of assessing diastolic function in SC |
E/e’ | E/e’ = E (cm/s)/e’ (cm/s) | Abnormal LV diastolic function suggested by average E/e’ > 14 cm/s [51] | Easy to acquire | Regional wall motion abnormalities and CAD will affect the measurement; limited accuracy in normal patients, or patients with annular calcification, mitral valve or pericardial disease; heterogeneity of values depending on patient age | Similar potential as e’; allows estimation of pulmonary capillary wedge pressure via formula: E/e’ + 4.6 | |
Right ventricle | Â | Â | Â | Â | Â | Â |
Systolic | TAPSE | MAX plane of systolic excursion of the lateral tricuspid annulus (mm) is measured using M-mode | Abnormal RV systolic function suggested by TAPSE < 17 mm [63]. | Easy to acquire; well demonstrated prognostic value | Only evaluates longitudinal myocardial shortening; dependent on angle; may be affected by LV systolic dysfunction and significant tricuspid regurgitation | Important associations with mortality [64] |