Tissue Doppler in critical illness: a retrospective cohort study

Area of Science:

• Critical Care Medicine
• Cardiology
• Echocardiography

Background:

• Limited published data exists on Tissue Doppler Imaging (TDI) in critically ill patients.
• This study investigates the distribution and correlation of TDI with other echocardiographic preload indices in this population.
• It aims to facilitate hypothesis generation and sample size calculations for future research.

Purpose of the Study:

• To assess the distribution of Tissue Doppler Imaging (TDI) variables in critically ill patients.
• To examine the correlation between TDI indices and other echocardiographic measures of preload.
• To explore associations between echocardiographic variables and mortality in the critically ill.

Main Methods:

• Retrospective study conducted in a combined medical/surgical tertiary referral intensive care unit.
• Transthoracic echocardiography with E/E' measurement was performed in 94 consecutive patients over a 2-year period.
• Analysis included assessment of TDI variables, E/E' ratio, and correlation with other echocardiographic parameters and mortality.

Main Results:

• TDI variables showed a wide range, with E' below 9.6 cm/s in 63 patients (indicating impaired myocardial relaxation) and E/E' above 15 in 14 patients (suggesting raised left ventricular filling pressure).
• E/E' correlated with left atrial area but not with inferior vena cava diameter or left ventricular end-diastolic volume.
• Increased left ventricular end-systolic volume, not E/E', was an independent predictor of 28-day mortality (OR 2.1, P = 0.007).

Conclusions:

• Tissue Doppler Imaging (TDI) values exhibit significant variability in critically ill patients.
• Diastolic dysfunction is prevalent, but E/E' is not strongly correlated with other preload indices.
• Left ventricular end-systolic volume warrants further investigation for risk stratification in critically ill patients.