We report the case of a 48 year old man who presented to his local A&E department following a stab injury to the right inferior parasternal area at the fourth intercostal space. He had been assaulted earlier in the day during an argument. On presentation he was slightly drowsy and complained of chest and upper abdominal pain. He was tachypnoeic and had a sinus tachycardia of 110 beats/min. His blood pressure was 100/60 mm Hg. Abdominal examination showed rigidity and guarding in the right upper quadrant. A chest radiograph showed a questionable widening of his mediastinum, and transthoracic echocardiography suggested a small anterior pericardial effusion with a mass consistent with thrombus on the anterior surface of the heart. He subsequently suffered an asystolic cardiac arrest and cardiopulmonary resuscitation was started. Emergency pericardiocentesis yielded 20 ml of dark blood and he was taken directly to the operating theatre at the referring district general hospital.

An emergency laparotomy and median sternotomy were carried out and a direct puncture to the anterior surface of the heart (presumed to be the right atrium) was identified. This was repaired with prolene sutures and the thrombus within the pericardial space was evacuated. Postoperatively, the patient remained on the intensive care unit (ICU) where he developed a left sided pneumonia and signs consistent with adult respiratory distress syndrome. A transthoracic echocardiogram at this time was reported as normal. The patient gradually deteriorated and by day 10 he had developed florid pulmonary oedema and haemoptysis. In addition, a new systolic murmur was reported. Repeat transthoracic echocardiography showed significant mitral regurgitation with a subaortic ventricular septal defect (VSD).

Following transfer to the St Thomas’ Hospital Cardiothoracic Centre, an emergency transoesophageal echocardiogram showed a tear in the anterior leaflet of the mitral valve, with severe regurgitation, and confirmed the VSD (fig 1). The patient was taken directly to the operating theatre where cardiopulmonary bypass was established, and the mitral valve was exposed through a Guiraudon incision which passed through the right atrium and across the atrial septum to enter the left atrium. The knife had entered the right ventricular wall, penetrated the ventricular septum (causing the VSD) and had lacerated the anterior mitral valve leaflet. The middle scallop of the anterior leaflet of the mitral valve was found to be detached (fig 2). The valve was repaired with interrupted 2-O ethibond sutures and the insertion of a 28 mm Cosgrove-Edwards annuloplasty band. The subvalvar VSD beneath the right coronary cusp of the aortic valve was repaired using interrupted ethibond sutures.

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Figure 1

 A transoesophageal echocardiographic image showing the two abnormal flow jets in systole—through the anterior mitral valve leaflet and the VSD—in line with the passage of the knife.

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Figure 2

 Intraoperative photograph showing a probe placed within the perforation of the anterior mitral valve leaflet.

The patient was discharged from the ITU after one day, was successfully rehabilitated, and was discharged from hospital after three weeks. Postoperative transthoracic echocardiography, done immediately before discharge from hospital, showed only mild transvalvar mitral regurgitation and no residual flow at the site of the VSD repair.

DISCUSSION

There are examples of traumatic ventricular septal defects with associated mitral valve damage in the medical literature but they are uncommon.^1,2 The rate of cardiac stabbings is increasing in the United Kingdom, so awareness of this condition is becoming more important. The importance of this case is that the full extent of the cardiac injury was not revealed until late. Initial echocardiographic findings were normal, but repeated investigations showed gross pathology. Similar findings have been described by Thandroyen and Mattison, who proposed that penetrating cardiac injury creates an intracardiac fistula which enlarges over time.³ In addition, it is postulated that thrombus formation or muscular spasm may initially seal small cardiac wounds. Such a mechanism may explain the delayed presentation which occurred in this case.

There are many published reports of traumatic VSDs but fewer reports of VSDs with associated mitral leaflet damage as a result of trauma, particularly stabbing.^1,2 Even in the absence of cardiac tamponade, significant intracardiac trauma may have occurred.¹ In the management of penetrating thoracic injuries it is important not to underestimate the full extent of potential injuries, which may often be greater than the inlet and exit injuries suggest. Careful consideration of the likely anatomical pathway, in accordance with the length of stabbing implement, aided by directed echocardiography are essential features of the management of such injuries. A high index of suspicion and repeated re-examination of the patient are important, and early liaison with a cardiothoracic centre is recommended.