Cardiac damage after polytrauma: the role of systematic transthoracic echocardiography - a pilot study

Heart injuries following polytrauma (PT) are identified as a predictor of poor outcome. The diagnostic algorithm of cardiac damage after trauma consists of the systemic measurement of cardiac damage markers, a 3-channel ECG and if there are any suspicious findings, the conduction of a transthoracic echocardiography (TTE). The aim of this study was to implement a systematic analysis of cardiac function using TTE in PT-patients. This study is a prospective non-randomized study, conducted in a German Level 1 Trauma Centre between January and July 2024. All polytraumatized patients with an ISS ≥ 16 were included immediately after entering the emergency department. Blood samples were withdrawn at 6 timepoints, at the Emergency room, 24 h, 48 h, three, five and ten days after admission to the hospital. Cardiac damage was measured by Troponin T (TnT) ECLIA, as well as NT-proBNP measurements. Entering the intensive care unit, transthoracic echocardiography was performed at two time points (day 1 and 2), by an experienced Cardiologist. During the pilot phase, cardiac contusion was detected in 14.3% of patients, with significantly elevated TnT levels on arrival, after 24 (**p ≤ 0.01) and 48 h (*p ≤ 0.05) compared to patients without cardiac contusion. Echocardiographic findings revealed that 25% of all patients had wall motion abnormalities, and 20% showed relaxation disorders. Right ventricular function, measured by TAPSE (tricuspid annular plane systolic excursion), RVEDD (right ventricular end diastolic diameter) and sPAP (systolic pulmonary arterial pressure), was slightly impaired in trauma patients, while the left ventricular function (ejection fraction (EF) and left ventricular end diastolic diameter (LVEDD)) was preserved. We observed the increase of TnT and an increase of the heart failure marker NT-proBNP over the time. These biomarkers were associated with pre-existing cardiac risk factors, the ISS and changes in the right or left ventricular function. Mitral valve insufficiency (grade 1) was present in 50% and tricuspid valve (grade 1) insufficiency in 30%. Taken together, we conducted for the first time of our knowledge, a systematic TTE analysis in PT-patients. We observed a slightly reduced right ventricular function, as well as mitral and tricuspid valve regurgitations in the patients.