report a case of traumatic herniation of the heart for which a CT scan and MRI made a major contribution to .... J H Sohn, J W Song, J B Seo et al. 448. The British ...
The British Journal of Radiology, 78 (2005), 447–449 DOI: 10.1259/bjr/31146905
E
2005 The British Institute of Radiology
Case report
Pericardial rupture and cardiac herniation after blunt trauma: a case diagnosed using cardiac MRI 1
J H SOHN, MD, 1J W SONG, MD, 1J B SEO, MD, 1K H DO, MD, 1J S LEE, MD, 2D K KIM, MD, K S SONG, MD and 1T H LIM, MD
1
Departments of 1Radiology and 2Thoracic and Cardiovascular Surgery, Asan Medical Center, University of Ulsan College of Medicine, 388-1 Poongnap-dong, Songpa-gu, Seoul 138-736, Korea
Abstract. Pericardial rupture following blunt chest trauma is rare, and is not usually diagnosed pre-operatively. If pericardial rupture is not recognized and treated promptly, it may be fatal owing to cardiac herniation. We report a case of traumatic herniation of the heart for which a CT scan and MRI made a major contribution to the diagnosis.
Pericardial rupture following blunt chest trauma is rare, and is not usually diagnosed pre-operatively, but should be suspected whenever there is severe blunt chest trauma. If pericardial rupture is not recognized and treated promptly, it may be fatal owing to cardiac herniation [1]. Few reports have emphasised the use of CT scanning as a tool for diagnosis and CT scan findings have not been well documented [2]; no report has emphasised the use of a MRI for diagnosis of the cardiac herniation. We report a case of traumatic herniation of the heart for which a CT scan and MRI made a major contribution to the diagnosis.
Case report A 55-year-old man arrived at the emergency department following a road traffic accident. At initial examination, he was fully conscious and haemodynamically stable. The anteroposterior (AP) chest radiograph (Figure 1a) showed multiple broken ribs on both sides, pulmonary vascular congestion and a pneumomediastinum. The cardiac silhouette was enlarged mainly due to enlargement of the left ventricle. A CT scan of the chest was performed using a General Electric Hi-speed (GE Medical Systems, Milwaukee, WI), slice thickness 7.5 mm, pitch50.93, 0.5 s per rotation, at 140 kV and 200 mA with contrast enhancement. This CT examination confirmed bilateral haemopneumothoraces and multifocal patchy consolidations in the right upper and left lower lobes due to pulmonary contusion. The heart was displaced into the left hemithorax with clockwise rotation of the cardiac apex (Figure 2a). At the level of the ventricles, the anterior surface of the right ventricle showed a wavy and undulated contour with focal dimpling (Figure 2b). From these CT findings, a diagnosis of cardiac herniation was suggested. Clinically, there was doubt about the diagnostic suggestion of pericardial rupture with cardiac herniation because of the patient’s good haemodynamic status and normal sinus rhythm on Received 5 August 2004 and in revised form 22 November 2004, accepted 17 January 2005. Address correspondence to Jae-Woo Song.
The British Journal of Radiology, May 2005
electrocardiogram. A follow-up chest radiograph showed improvement in the pulmonary contusion, however, the cardiac outline remained abnormal and there was collapse of the left lower lobe and a left pleural effusion (Figure 1b). On the 12th day after admission, MRI of the chest was performed using a 1.5 T unit (Intera CV; Philips, DA, Netherlands). Cine MRI was performed in coronal images, using a breath-hold balanced fast field-echo sequence (repetition time/echo time (TR/TE) 3.4 ms/1.7 ms; flip angle 50 ˚; field of view 350 mm; matrix 2566256; slice thickness 8 mm). MR examination showed clockwise rotation of the cardiac axis with compression of the left inferior pulmonary vein between the aorta and left ventricle with left lower lobe collapse. On the coronal cine MRI, there was an exaggerated up- and downmovement of the cardiac apex, separated from the left hemi-diaphragm by a left pleural effusion (Figure 3a, b). Because the separated movement between the cardiac apex and left hemi-diaphragm was distinct, pleuropericardial rupture and cardiac herniation was diagnosed. On the 16 day after admission, the patient underwent a thoracotomy; this confirmed that the heart was dislocated from its pericardium, which was torn from the level of the left upper pulmonary vein to the left hemi-diaphragm and located within the left pleural cavity. The tear was vertical, 12 cm long, and located just behind the phrenic nerve. The heart was relocated and the pericardial tear was repaired.
Discussion In a review of the literature, Clark et al [3] reported on 142 traumatic ruptures of the pericardium. The left pleuropericardium was injured in 71 (50%), the right pleuropericardium in 24 (17%), the diaphragmatic pericardium in 39 cases (27%) and the superior mediastinal pericardium in 6 cases (4%). A cardiac herniation was found in 31 of left and 5 of right pleuropericardial defects, and in 4 diaphragmatic tears of the pericardium. We have noted 55 additional cases of pericardial ruptures since 1987 on performing a literature search, 35 (64%) of the cases being complicated with cardiac herniation. In cases with 447
J H Sohn, J W Song, J B Seo et al
(a)
(b)
Figure 1. 55-year-old man with history of road traffic accident. (a) The initial anteroposterior (AP) chest radiograph shows multiple broken ribs on both sides, pulmonary vascular congestion and pneumomediastinum. The heart shadow is enlarged mainly due to enlargement of the left ventricle. (b) On the 14th day after admission, the follow-up chest radiograph shows decreasing extent of the opacities owing to contusion and vascular congestion. However, the cardiac outline remains obliterated and there is collapse of the left lower lobe and left pleural effusion.
ruptured diaphragmatic pericardium, abdominal protrusion of viscera into the pericardial sac may occur, but cardiac herniation is rare. In ruptured pleuropericardium, the tear is most often located along the phrenic nerve and when the tear is large enough, the heart may be dislocated. Dislocation of the heart may result in a torsion along an axis made by the inferior vena cava and the great vessels with strangulation of the heart [4]. Pericardial rupture is often reported as an incidental finding at emergency thoracotomy or laparotomy in patients with multiple trauma. The survival rate of patients
who reach hospital alive and are diagnosed as having pericardial rupture is poor, ranging from 36.4% to 42.9% [5, 6]. As cardiac herniation is more complicated, most of the reported survivors had stable haemodynamics on arrival and were treated promptly in hospital when cardiac herniation occurred a few days after admission. According to a report in the Japanese literature [7], a pre-operative diagnosis of cardiac herniation was made in four out of eight patients, by chest radiography in two, by cardiac angiography in one, and by chest CT in one patient. In the other four patients, the diagnosis was made incidentally at
(a)
(b)
Figure 2. Chest CT findings. (a, b) Chest CT scans show displacement of the heart and clockwise rotation of the cardiac apex. The anterior surface of the right ventricle shows a wavy and undulated contour with a focal dimpling (arrow in Figure 2b). 448
The British Journal of Radiology, May 2005
Case report: Cardiac MRI of pericardial rupture and cardiac herniation
(a)
(b)
Figure 3. Cardiac cine-MRI findings. (a) Coronal cine MRI at the diastolic and (b) systolic phases demonstrate an exaggerated upand down-movement of the cardiac apex, separated from the left hemidiaphragm by pleural effusion, suggesting pleuropericardial rupture and cardiac herniation.
thoracotomy. The pericardial rupture was on the left side in six patients and on the right side in two, and all ruptures ran along the phrenic nerve. When our patient was admitted to hospital, we suspected a pericardiac rupture with cardiac herniation on CT. This patient was a haemodynamically stable and transoesophageal echocardiogram did not find any sign of pericaridial tear or cardiac herniation, so this rare occurrence in cardiac dislocation made the diagnosis difficult. Surprisingly, haemodynamic conditions were preserved in the five cases of right cardiac herniation in report of Clark et al [3]. In our case, cardiac MRI confirmed the diagnosis of cardiac herniation. This case report describes the first known successful MRI diagnosis of cardiac herniation associated with traumatic rupture of the pericardium.
References 1. Janson JT, Harris DG, Pretorius J, Rossouw GJ. Pericardial rupture and cardiac herniation after blunt chest trauma. Ann Thorac Surg 2003;75:581–2.
The British Journal of Radiology, May 2005
2. Schir F, Thony F, Chavanon O, Perez-Moreira I, Blin D, Coulomb M. Blunt traumatic rupture of the pericardium with cardiac herniation: two cases diagnosed using computed tomography. Eur Radiol 2001;11:995–9. 3. Clark DE, Wiles C III, Lim MK, Dunham CM, Rodriguez A. Traumatic rupture of the pericardium. Surgery 1983;93:495– 503. 4. Thomas P, Saux P, Lonjon T, et al. Diagnosis by videoassisted thoracoscopy of traumatic pericardial rupture with delayed luxation of the heart: case report. J Trauma 1995;38:967–70. 5. Kato K, Henmi H, Yamamoto Y, Mashiko K, Kimura A, Kushimoto Y, et al. An evaluation of blunt traumatic pericardial rupture (in Japanese with English abstract). JJAAM 1992;3:163–72. 6. Fulda G, Rodriguez A, Turney SZ, Cowlew RA. Blunt traumatic pericardilal rupture. A ten-year experience 1979 to 1989. J Cardiovas Surg 1990;31:525–30. 7. Matsuda S, Hatta T, Kurisu S, Ohyabu H, Koyama T, Kita Y. Traumatic cardiac herniation diagnosed by echocardiography and chest CT scanning: report of a case. Surg Today 1999;29:1221–4.
449
