Identifying the broken heart: predictors of mortality and morbidity in suspected blunt cardiac injury

Abstract

Background: Blunt cardiac injury (BCI) is an infrequent but potentially fatal finding in thoracic trauma. Its clinical presentation is highly variable and patient characteristics and injury pattern have never been described in trauma patients. The aim of this study was to identify predictors of mortality in BCI patients.

Methods: We performed an 8-year retrospective analysis of all trauma patients diagnosed with BCI at our Level 1 trauma center. Patients older than 18 years, blunt chest trauma, and a suspected diagnosis of BCI were included. BCI was diagnosed based on the presence of electrocardiography (EKG), echocardiography, biochemical cardiac markers, and/or radionuclide imaging studies. Elevated troponin I was defined as more than 2 recordings of greater than or equal to .2. Abnormal EKG findings were defined as the presence of bundle branch block, ST segment, and t-wave abnormalities. Univariate and multivariate regression analyses were performed.

Results: A total of 117 patients with BCI were identified. The mean age was 51 ± 22 years, 65% were male, mean systolic blood pressure was 93 ± 65, and overall mortality rate was 44%. Patients who died were more likely to have a lactate greater than 2.5 (68% vs 31%, P = .02), hypotension (systolic blood pressure < 90) (86% vs 14%, P = .001), and elevated troponin I (86% vs 11%, P = .01). There was no difference in the rib fracture (58% vs 56%, P = .8), sternal fracture (11% vs 21%, P = .2), and abnormal EKG (89% vs 90%, P = .6) findings. Hypotension and lactate greater than 2.5 were the strongest predictors of mortality in BCI.

Conclusions: BCI remains an important diagnostic and management challenge. However, once diagnosed resuscitative therapy focused on correction of hypotension and lactate may prove beneficial. Although the role of troponin in diagnosing BCI remains controversial, elevated troponin may have prognostic significance.

Keywords: Blunt cardiac injury; Cardiac contusion; Predictors of mortality.