Right Luxation of the Heart

Abstract

Rupture of the pericardium with luxation of the heart after blunt trauma is a fairly rare condition but carries a high mortality rate. In this report, we describe our experience with a case of right luxation of the heart in a young patient with multiple injuries due to an automobile accident. The patient, who was in hemodynamic failure, underwent successful emergency surgical treatment to replace the heart in its anatomic site. We discuss the diagnosis and management of this dangerous event. (Tex Heart Inst J 2003;30:140–2)

Ruptures of the heart and pericardium from blunt trauma of the chest are due, in more than 60% of cases, to automobile accidents. ¹ Such accidents provide all the components required of this injury's pathophysiologic mechanism: high-energy impact of the vehicle, followed by rapid deceleration of the body and direct impact of the precordial region, usually with the steering wheel. The resultant compressive and expansive forces transmit their energy to the blood within the cardiac chambers, which can produce laceration of the myocardial wall, tears in the valve apparatus (often the tricuspid valve), and pericardial rupture. When such rupture occurs, the heart can move into the right or left pleural cavity, which compromises further the hemodynamic stability of the patient. Luxation of the heart after blunt chest trauma carries a high mortality rate, ² because of quickly evolving hemodynamic failure and delays in diagnosis and surgical intervention. ³ We report our experience with a case of right luxation of the heart in a young patient with multiple traumata.

Case Report

In May 2001, a 21-year-old man sustained multiple injuries in an automobile accident, including blunt trauma to the thorax and abdomen, with pulmonary contusion but no rib fractures. When he was admitted to a regional hospital, the 1st surgical procedure that he underwent was a splenectomy. Then he was admitted to the intensive care unit (ICU) at our institution because of increasing hemodynamic failure. He required orotracheal intubation and tube thoracostomy for pneumothorax. The 1st chest radiograph, which had been obtained at the regional hospital, did not show any features that suggested cardiac dislocation. However, successive radiographs obtained during the 48 hours after ICU admission showed the evolution of an abnormal cardiac silhouette, in the form of right dislocation of the heart (Fig. 1). This diagnosis was confirmed by transthoracic echocardiography, which showed compression of the left atrium, and by computed tomographic angiography (Figs. 2 and 3).

Fig. 1 Progressive right luxation of the heart. A) Chest radiograph obtained 24 hours after intensive care unit (ICU) admission shows abnormal cardiac silhouette with early displacement of the heart into the right hemithorax and persistence of a right pneumothorax that had required tube thoracostomy at ICU admission. B) Chest radiograph obtained 48 hours after ICU admission shows clear right luxation of the heart.

Fig. 2 Scout film obtained before computed tomography shows evidence of displacement of the heart into the right hemithorax and of right pneumothorax.

Fig. 3 Computed tomographicic (CT) scan, obtained soon after the chest radiograph shown in Fig. 1B, shows evidence of rightward displacement of the heart into the right hemithorax and of right pneumothorax. There is no chest tube in the image, because it was removed before CT examination, to clear an obstruction. The tube was not replaced, because the patient underwent emergency cardiac surgery soon after.

A Swan-Ganz catheter was inserted. About 12 hours after Swan-Ganz catheterization, the patient's hemodynamic condition deteriorated as shown by a rising central venous pressure (18 mmHg) and heart rate (120 bpm), with reduction of cardiac output (2.1 L/min), a cardiac index of 1.8, and a blood pressure of 80/40 mmHg. Therefore, he underwent emergency surgical treatment.

Surgical Technique

Approach via a midline sternotomy revealed a sternal fracture and a large tear in the right side of the pericardium. The protruding heart had rotated around the pulmonary veins in such a manner that vascular flow was constricted and the left atrium was not filling adequately; this had caused total circulatory collapse. We opened the pericardium completely and replaced the heart in its anatomic site, which resulted in rapid recovery of cardiac output and in subsequent recovery of the other hemodynamic values. We closed the pericardium with interrupted 3–0 polypropylene sutures while avoiding injury to the phrenic nerve. A drain was left in the pericardial space. Cardiopulmonary bypass was not needed because of the rapid recovery of hemodynamic stability and the absence of a myocardial or major vascular lesion.

During the postoperative course, transthoracic echocardiography showed grade 2 tricuspid regurgitation that had not been observed before surgery. Operation for tricuspid valve repair was delayed, because systemic heparinization would have involved a high risk of massive hemorrhage from the patient's intra-abdominal lesions; moreover, mild tricuspid regurgitation was well tolerated in this otherwise healthy young patient. The postoperative chest radiograph was normal. The postoperative course was otherwise uncomplicated, and the patient was discharged on the 8th postoperative day. At his 1-year follow-up visit, this patient was asymptomatic and displayed only residual grade 2 tricuspid regurgitation on echocardiography.

Discussion

The medical literature reports an approximate 2% incidence of heart injury after major blunt trauma of the thorax. ⁴ Traumatic luxation of the heart is a fairly rare condition, sometimes associated with tricuspid valve rupture. ⁵ However, the true incidence may be underestimated, because many patients with traumatic cardiac luxation do not arrive at the hospital alive—the estimated mortality rate is about 30%. ^1,3

In a trauma patient, a heart murmur may be the only indication of a valve lesion. Transthoracic or transesophageal echocardiography should be performed immediately and repeated serially, because delayed rupture of a papillary muscle is relatively common, ^6,7 even after a normal 1st exam.

Rupture of the pericardium with dislocation of the heart is difficult to diagnose early. Often, a patient with this condition is stable hemodynamically, probably because those who reach the hospital alive constitute a favorable group; but the situation can change quickly and threaten the patient's life. Chest radiography often shows only trivial features of dislocation, such as an abnormal cardiac silhouette, which is easily overlooked ¹ in the presence of traumatic abdominal and cerebral injuries. In suspect cases, careful Swan-Ganz catheter monitoring of patients in the ICU will reveal hemodynamic instability. Serial echocardiograms and daily chest radiographs are useful in the early diagnosis of cardiac luxation, to ensure appropriate surgical treatment. Furthermore, respiratory support in the ICU plays a critical role, because many patients suffer from pulmonary contusion and therefore need positive end-expiratory pressure (PEEP) during ventilation. Additionally, PEEP can prevent the heart from rotating farther away and thereby help prevent deterioration of preload and its attendant hemodynamic collapse. ³