Blunt Cardiac Injury

Blunt cardiac injury (BCI) encompasses a spectrum of conditions resulting from blunt chest trauma, ranging from minor myocardial bruising to severe, life-threatening cardiac rupture. While a minority of patients exhibit abnormal electrocardiogram (ECG) results or signs of shock, most present with no symptoms initially. However, the risk of sudden arrhythmias or cardiac pump failure necessitates consideration of BCI to ensure appropriate monitoring and treatment.

The term "cardiac contusion" has traditionally been used to describe heart injuries following blunt chest trauma. Histologically, a cardiac contusion is marked by a contused myocardium with hemorrhagic infiltrate, localized necrosis, and edema. These findings are most definitively confirmed during surgery or autopsy. However, the clinical term blunt cardiac trauma is now preferred, as it encompasses the broad range of potential cardiac injuries resulting from blunt chest trauma.

Between 2017 and 2021, according to the National Trauma Data Bank, a reported 14,219 out of 4.8 million patients with blunt trauma patients were diagnosed with BCI, resulting in a 0.3% overall incidence rate. BCIs can be further described by specific injuries or observed dysfunction. Significant BCI is usually associated with high-impact trauma, with motor vehicle accidents accounting for 50% of cases, pedestrians struck by motor vehicles for 35% of cases, motorcycle crashes for 9% of cases, and falls from significant heights for 6% of cases.

Diagnosing BCI is challenging due to the lack of standardized diagnostic criteria and a definitive diagnostic test. The difficulty is compounded in polytrauma patients. The reported incidence of cardiac injury following blunt chest trauma ranges from 8% to 76%, primarily due to the absence of established diagnostic guidelines. In patients without severe arrhythmias and hemodynamic instability, the significance of BCI is sometimes debated. In the setting of blunt trauma, a high clinical suspicion for BCI is required, and certain patients should be monitored for adverse sequelae; no pathognomonic clinical signs or symptoms have been supported by evidence that correlates with the risk of cardiac complications. Consequently, the sequelae of BCI are more important than its label.