Blunt cardiac injury

Mechanism of injury

BCI arises from a variety of mechanisms including:

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  Direct precordial impact

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  Crush injury resulting from compression between the sternum and spine

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  Deceleration or torsion causing a tear in the heart at a point of fixation, such as between the right atrium and vena cava

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  Hydraulic effect resulting in rupture, such as that seen during an abrupt abdominal compression that results in significantly elevated venous pressure that is transmitted to the right atrium or ventricle

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  Blast injury [2], [8]

These

Pattern of injury

The right heart is the most the most common site of BCI [2], [13]. This finding is likely the result of steering wheel–anterior chest wall impact injuries and the anterior location of the right atrium and ventricle within the mediastinum (Table 1) [2], [14]. Concurrent injury to more than one chamber has been documented in over 50% of BCI patients [15]. For those patients with blunt traumatic rupture of the heart, the risk of having more than one chamber ruptured is over 20% [16]. Of those

Natural history

Minor ECG or cardiac enzyme abnormalities secondary to BCI usually resolve over time, and most areas of dyskinesia or dysrhythmias will recover proper function within a few hours [3], [17]. BCI with complex arrhythmias can cause heart failure, which if severe, can result in death [18], [19]. BCI with cardiac-free wall rupture or laceration of a coronary artery that causes extracardiac hemorrhage is usually fatal and results in deaths at the scene of the injury [2], [6], [11], [20], [21], [22].

Diagnosis of BCI

Few clinical signs or symptoms are specific for BCI [6]. The most common finding associated with BCI is chest pain [35]. This pain may or may not be anginal in nature, and it is usually a result of associated thoracic trauma. Because BCI is usually the result of a high-velocity impact, associated injuries are common (Table 2). Dyspnea, chest wall ecchymoses, flail chest, and sternal fractures should raise suspicion for BCI [4], [19], [36], [37], [38], [39]. Cardiac dysfunction can cause

Management of BCI

Therapeutic interventions currently focus on the treatment of BCI-related complications. BCI with minor ECG or cardiac enzyme abnormalities rarely produce clinically significant sequela, and these minor abnormalities usually resolve without any intervention within 24 hours [3], [5], [17], [41], [45], [52], [54], [55], [62], [75]. Anecdotal reports have shown that antiarrhythmias can treat BCI with complex arrhythmias [5], [19], [50], [75].

BCI with heart failure requires a precise understanding

Long-term cardiac function after BCI

Only a few studies have evaluated the long-term effects of BCI [73], [77], [78]. Stuartis et al evaluated 44 patients who had sustained a traumatic myocardial contusion [77]. These patients were compared with a control cohort of patients matched for injury severity without cardiac injury. At follow-up, 13 patients with BCI were indistinguishable from the control group of 12 patients, according to the New York Heart Association classification. Left and right ventricular ejection fractions were

Summary

In summary, the incidence of BCI following blunt thoracic trauma patients has been reported between 20% and 76%, and no gold standard exists to diagnose BCI. Diagnostic tests should be limited to identify those patients who are at risk of developing cardiac complications as a result of BCI. Therapeutic interventions should be directed to treat the complications of BCI. Finally, the prognosis and outcome of BCI patients is encouraging