[Value of transesophageal echocardiography in the assessment of blunt chest trauma: correlation with electrocardiogram, heart enzymes, and transthoracic echocardiogram].

OBJECTIVE To asses the feasibility, usefulness and clinical rentability of the transesophageal echocardiography (TEE) in the evaluation of patients suffering a severe blunt chest trauma as well as to correlate the TEE findings with those provided by the conventional electrocardiogram (ECG), cardiac isoenzymes assay and transthoracic echocardiography (TTE). DESIGN Prospective study using ECG, blood cardiac enzymes assay, TTE and TEE. SETTING Intensive care unit of a general hospital. PATIENTS We studied 34 patients admitted with blunt chest trauma and suspected cardiac contusion in spite of the existence of other traumatic injuries in some of them. There were 23 (67.6%) males and 11 females, with a mean age of 37.1 +/- 19.4 years (range: 16-69 years). MATERIAL AND METHODS Patients with a previous history of cardiovascular or chronic pulmonary disease, cardiac arrest upon admission or positive cocaine or amphetamine levels in the urine were excluded from the study. Suspected cardiac contusion was established by clinical data, electrocardiographic findings, enzymes blood values (CPK-total and MB-fraction) and TTE findings. Additionally, a TEE was performed in each patient. Patients were stratified into two groups according to the TEE findings: Group A patients had signs compatible with cardiac contusion and in Group B patients there was a lack of evidence to substantiate this diagnosis. Those tests were evaluated in respect to their accuracy in the diagnosis of cardiac contusion when compared to transesophageal echocardiography and TEE findings were compared, whenever possible, to surgical or necropsic findings. RESULTS We found TEE signs of cardiac injury in 22 (64.7%) patients and a wide spectrum of traumatic cardiac abnormalities were identified. TEE signs of ventricular injury were found in 15 pts of Group A (68.2%) being the right ventricle the most frequent affected. There were also two cases of mitral leaflet rupture, one case of tricuspid valve prolapse (with severe tricuspid regurgitation and associated with right ventricle wall motion abnormalities) and seven cases of pericardial effusion as well as one case of thoracic aortic dissection. In every patient submitted to cardiothoracic surgery or necropsy the TEE findings were confirmed. TEE provided significant information, sometimes crucial, to the patient evaluation and management, it was performed without any difficulty and it doesn't carried out any related complication. TTE was technically suboptimal in 53% and fail to demonstrate many cases of cardiac contusion and the thoracic aorta lesion, being the number of cardiovascular injuries demonstrated by TEE significantly higher (p = 0.029). No statistically significant difference was found between the number of patients with either an abnormal ECG or high values of CPK-MB in each group. Neither clinical findings, cardiac enzymes values, serial ECG's nor TTE predicted all the patients who had traumatic cardiac injury and those would subsequently developed complications related to cardiac contusion. CONCLUSIONS A severe blunt chest trauma frequently results in cardiac injury. The ECG and the CPK-MB measurements appears both to be fairly sensitive and specific tests in the cardiac contusion diagnosis. TTE has shown to have important limitations in these patients, thus not allowing neither a complete echo evaluation nor a reliable one. TEE plays an important role in the evaluation and management of this type of patients providing rapid diagnostic information and being of high value in the rule out cardiac contusion as well as in the establishment of a specific diagnosis of cardiac and/or thoracic aorta injuries with a consequent better assessment and treatment strategy in these patients.