Management of contained penetrating cardiac injury in a patient with prior cardiac surgery

Abstract

Penetrating cardiac injuries usually require emergent surgical intervention. Our patient presented to the trauma centre with multiple stab wounds to the neck, chest, epigastric region and abdomen. She arrived haemodynamically stable, and her initial Focused Assessment with Sonography for Trauma exam was negative. Her chest X-ray did not show any evident pneumothorax or haemothorax. Due to her injury pattern, she was taken to the operating room for exploratory laparotomy and neck exploration. Postoperatively, she was taken for CT and found to have a contained cardiac rupture. The injury was contained within previous scar tissue from her prior cardiac surgery. Further evaluation revealed that the injury included a penetrating stab wound to the right ventricle and a traumatic ventricular septal defect (VSD). She subsequently underwent a redo sternotomy with the repair of the penetrating stab wound and the VSD. Cardiology, intensive care, trauma surgery and cardiothoracic surgery coordinated her care from diagnosis, management and recovery. This case highlights the challenges in the management of cardiac injuries and the benefits of a multidisciplinary approach to care for complex cardiac injuries.

Background

In the USA, the percentage of penetrating cardiac trauma (PCT) caused by gunshot wounds is equal to or higher than that from stab wounds.¹ Conversely, in underdeveloped countries, stab wounds comprise most of PCT.² In the past 10 years, PCT has grown proportionately compared with blunt cardiac injury and carries a higher mortality rate.³ Over half of PCT victims succumb to their injuries prior to hospital arrival, and those who do make it to the hospital often arrive haemodynamically unstable. PCT to the cardiac box typically results in haemopericardium from ventricular rupture, with more complex injuries including septal rupture, damage to coronary vasculature or valvular damage. These patients usually require emergent operative intervention via median sternotomy or left thoracotomy.^1–4 If a patient arrives haemodynamically stable, the picture is less clear. Similarly, an emergent sternotomy is challenging in patients with previous cardiac surgery, and pericardial adhesions can contain or limit the typical haemodynamic instability usually seen on presentation. Here, we present a unique case where a PCT was identified in a patient with a history of prior cardiac surgery several hours after presentation.

Case presentation

A female patient in her 60s with a history of three-vessel coronary artery bypass graft (CABG) 5 years prior to presentation, heart failure with preserved ejection fraction, and chronic obstructive pulmonary disease presented to the trauma centre following an assault with multiple stab wounds. She arrived haemodynamically stable. She conversed appropriately and participated in the patient interview. An initial physical exam revealed stab wounds in the anterior mid-neck, anterior left chest and two anterior wounds in the epigastrium and the right upper quadrant. The stab wound to the chest was within the cardiac box (the anatomical space between the clavicle, midclavicular line and xyphoid).

Investigations

In the emergency department (ED), her Focused Assessment with Sonography for Trauma (FAST) was negative, and chest X-ray (CXR) demonstrated no pneumothorax or haemothorax. She was taken emergently to the operating room due to peritoneal and platysma violations. Intraoperatively, her only identifiable injury was a 4 cm liver laceration for which electrocautery was used for haemostasis and hepatorrhaphy was performed. At this time, the team elected not to perform a pericardial window given her haemodynamic stability on presentation to the ED, her FAST exam being negative for haemopericardium in two cardiac views, and a CXR showing no evidence of cardiomegaly. Her neck exploration identified no significant vascular injury.

After the operation, she underwent CT to complete her trauma workup and identify any other injuries. The CT revealed a laceration to the mid-portion of the right ventricle (RV) anterior wall with a new haematoma formation within the anterior mediastinum measuring 5.7×3.2 cm (figure 1).

Figure 1.

CT scan with evidence of contained cardiac rupture. The patient was taken for CT imaging immediately following her initial operation. The arrows draw attention to the contained cardiac rupture from her right ventricle contained within postoperative adhesions as seen on sagittal images (A) and coronal images (B).

A transthoracic echocardiogram (TTE) was obtained emergently in the intensive care unit, which showed overall preserved LV function with some septal hypokinesis. It identified a perforated anterior RV with extravasation noted that was well contained within the mediastinum anterior to the RV. Furthermore, there was a tear across the ventricular anteroseptum of 0.45 cm near the apex, which was consistent with a traumatic ventricular septal defect (VSD). Cardiac surgery and cardiology were consulted. Cardiology performed a left heart catheterisation to further evaluate her injury and her previous bypass. Cardiac catheterisation showed an atretic left internal mammary artery (LIMA) to left anterior descending artery (LAD) bypass. The LAD was patent with multiple collateral vessels. Two vein grafts to the obtuse marginal artery and right coronary artery were patent. The left main coronary artery had 90% stenosis near the ostium and was heavily calcified. In addition, a contained perforation of the septal artery was visualised (figure 2).

Figure 2.

Left heart catheterisation demonstrating perforation of a septal branch off of the left anterior descending coronary artery (LAD). Left heart catheterisation was performed after confirmation of free perforation on a transthoracic echocardiogram. Two of her previous bypass grafts, with the exception of the left internal mammary artery to LAD bypass, were patent. The arrow points to a contained perforation of a septal branch off of the LAD.

Treatment

The trauma team transferred the patient to the cardiovascular intensive care unit (CVICU). During this interval, the patient remained haemodynamically stable. This time allowed for the trauma team, cardiology and cardiothoracic surgery to plan the definitive repair of her cardiac injury. The consensus was made to allow the patient to recover from her initial operation and to monitor for any signs of intra-abdominal bleeding as the cardiac operation would necessitate systemic heparinisation. Furthermore, haemodynamics were closely monitored by CVICU and cardiology. The planned operation involved repairing the RV defect as well as the VSD. The patient was taken to the operating room 3 days after her initial operation. A redo sternotomy was performed, and the right hemisternum was mobilised. The patient was then placed on femoral cardiopulmonary bypass. The haematoma was identified and the RV perforation was controlled with compression while the remainder of the adhesions were dissected free to mobilise the heart. An injury to the RV, several centimetres below the pulmonary valve parallel to the LAD, was noted and repaired using 4-0 Prolene pledgeted suture in a horizontal mattress style. Intraoperatively, anaesthesia performed a transoesophageal echocardiogram (TEE) that confirmed the presence of a VSD (figure 3). This was repaired externally by passing a suture from the LV side, under the LAD, to the RV to close the defect and the proximal portion of the laceration (4-0 prolene pledgeted suture in horizontal mattress style) (figure 4). No ECG changes were identified postbypass. Postrepair TEE demonstrated a minimal residual VSD.

Figure 3.

Transoesophageal echocardiogram (TEE) demonstrating a ventral septal defect (VSD). TEE shows a VSD that was previously missed on the transthoracic echocardiogram. The VSD was repaired primarily and the size of the VSD shrunk on repeat TTE.

Figure 4.

Operative repair of right ventricle and ventricular septal defect (VSD). The image on the left depicts the injury pattern of the heart. The RV (Right Ventricle) was injured lateral to the LAD (Left Anterior Descending Artery), and the VSD was close to the anterior wall of the heart. RV was repaired with 4-0 prolene pledgeted suture in horizontal mattress fashion.¹ The VSD was repaired with 4-0 prolene pledgeted suture in horizontal mattress fashion from the LV (Left Ventricle) side, under the LAD, and incorporated the VSD to approximate it to the anterior wall.² LAD, left anterior descending; RV, right ventricle.

Outcome and follow-up

Her postoperative course was unremarkable. Repeat imaging immediately prior to discharge revealed no new anterior wall or septal hypokinesis and normal RV function. No additional treatment was required for the traumatic VSD. The patient had an unremarkable recovery with eventual discharge to an inpatient rehabilitation facility. She is scheduled for a follow-up with outpatient cardiology as well as a follow-up TTE.

Discussion

This unique case demonstrates the potential option in which the patient undergoes delayed definitive repair of her penetrating cardiac injury in the setting of prior cardiac surgery. Her initial presentation was unusual given her injury did not cause a cardiac tamponade physiology. Given the amount of adhesions present, it is likely that the haematoma was confined in the anterior mediastinum and not concentrically around the heart. Furthermore, it is reported in the literature that patients could present with late presentation of tamponade after their initial injury.⁵ However, from our literature search, this is the first case in which a traumatic ventricular rupture was contained due to her adhesions from her prior CABG. Although FAST exams have gained acceptance within the initial workup of trauma patients, there are still some limitations on their utility in identifying cardiac injuries.^6–8 Given the negative FAST and no haemodynamic signs of cardiac injury, the pericardial window was not performed despite the injury being located within the cardiac box. This unusual presentation allowed for a delayed definitive repair of her cardiac injury.

In the case that the patient presented haemodynamically unstable, with high suspicion for cardiac injury, venoarterial extracorporeal membrane oxygenation (ECMO) can be used.^{9 10} ECMO can be initiated in the ER (Emergency Room) for temporary circulatory support until definitive repair. If the patient presented to the ER with a loss of pulse, an ER thoracotomy can be used. ER thoracotomy, per the Eastern Association for the Surgery of Trauma, is a useful adjunct in patients with penetrating thoracic injury with associated loss of pulse.¹¹ Typically, it involves a left anterolateral thoracotomy incision, but in the case of suspected injury on the left thorax, it can be extended to a bilateral anterior thoracosternotomy (clamshell incision).¹² The goal of these procedures in the case of penetrating cardiac injury is to open the pericardium to relieve tamponade and temporise any apparent injuries to the heart.

In all cases, all PCTs need to be repaired operatively. Left anterolateral thoracotomy and clamshell incisions are common in ER thoracotomy. If already made, these incisions can be used to repair any cardiac or other thoracic injuries. However, median sternotomy is the classic approach to repairing cardiac injuries. Furthermore, median sternotomy should be performed if a diagnostic pericardial (either subxiphoid or transdiaphragmatic through a laparotomy incision) window was positive.^{12 13} The most commonly injured chamber for any PCT is the RV, thus a median sternotomy will provide good exposure for such an injury.⁴ However, if the injury is located in any posterior structure, the heart can be lifted up with careful attention to monitor for profound hypotension, bradycardia and arrest.¹³ In simple ventriculotomy, a pledgeted prolene suture (4-0) in horizontal mattress fashion can be used to approximate the defect.¹³ Although most VSDs need a more extensive repair, our team elected to repair it using an external approach given the defect was adjacent to the anterior wall. Digital compression over the injury and foley catheter insertion through the injury can achieve temporal haemostasis. These manoeuvres can also be performed immediately after an ER thoracotomy. Furthermore, in the case of uncontrolled haemorrhage, Sauerbruch grip or manoeuvre can be used.² This involves temporary total cardiac occlusion by compressing the junction between the vena cava and the right atrium. In the case of extensive uncontrolled haemorrhage, laceration of the proximal major coronary arteries or any valvular injuries, the patient should be placed on cardiopulmonary bypass.¹⁴

The patient’s injuries required a surgical repair but the overall care of the patient required a multidisciplinary approach. Once the cardiac injury was identified, trauma surgery, cardiology, CVICU and cardiothoracic surgery coordinated the definitive repair of her cardiac injury. Cardiology confirmed a VSD through the left heart catheterisation and identified an atretic LIMA graft. Coordinating with the trauma team, the decision was made to allow the patient to recover from her initial laparotomy and monitor her liver laceration prior to the definitive cardiac repair. Cardiology, as well as CVICU, monitored her haemodynamics while in the CVICU. Given the findings from the cardiac catheterization showing multiple collateral vessels coming from the LAD, Cardiology and cardiothoracic decided to not perform further coronary bypass. All teams were equally involved in aiding the full recovery of this patient. Although there were some wall motion abnormalities that were observed immediately following surgery, these generally improve over time, as seen in this case.¹⁵ A multidisciplinary team is essential in help diagnosing and managing any patients with a complex penetrating cardiac injury.

Learning points.

• Diagnosing penetrating cardiac injury can have a delayed presentation in patients with prior cardiac surgery.

• Multiple imaging modalities are helpful and can be complementary in determining the extent of penetrating cardiac injuries.

• Multidisciplinary approach is effective and the use of repeat and/or multiple imaging modalities is required for patients with penetrating cardiac injuries.

Ethics statements

Patient consent for publication

Consent obtained directly from patient(s).