Self-inflicted gunshot wound to the right coronary artery in a pediatric patient resulting in sternotomy and coronary artery stenting

Abstract

Penetrating gunshot wounds to the heart are rare in children but can lead to severe complications requiring urgent intervention. This report describes a case of a 14-year-old male who sustained a gunshot wound to the anterior chest from a high-velocity pellet rifle, resulting in hemopericardium, cardiac tamponade, and potential injury to the right coronary artery. Following emergency surgery and the successful evacuation of a clot containing the pellet, the patient experienced ventricular fibrillation and was subsequently taken for percutaneous coronary intervention due to a middle right coronary arterial occlusion. Two drug-eluting stents were placed, restoring blood flow to distal vessels. Postoperatively, the patient was managed with antiplatelet therapy, including ticagrelor and aspirin. The case highlights the successful use of cardiac catheterization in a pediatric trauma patient and underscores the need for further research on optimal antiplatelet therapy in this population to prevent complications such as restenosis and stent thrombosis.

Introduction

Penetrating gunshot wounds (GSW) of the heart are predominantly seen in adults and are rare in children [1]. Given the severity and potential complications of penetrating cardiac injuries, effective treatment strategies are crucial. The anterior aspect of the heart, particularly the right ventricle is highly susceptible to injury, although it is not uncommon for multiple cardiac structures to be damaged [2]. Penetrating cardiac injuries typically result in cardiovascular compromise due to either bleeding or pericardial tamponade which require surgical intervention [2]. These injuries can also give rise to additional complications including atrial and ventricular septal defects, valvular disruption, and trauma to the coronary arteries [3]. Percutaneous coronary intervention (PCI) is commonly used in adult patients with coronary artery disease. Limited data exists on PCI use in pediatric coronary artery injuries. However, employing drug-eluting stents via PCI can provide life-saving therapy, minimizing further complications in pediatric patients [4]. Close follow-up is crucial. Here, we present a rare but complex case of a 14-year-old patient who sustained penetrating injury to the heart requiring placement of drug eluting stents and lifelong antiplatelet therapy.

Case report

The patient is a 14-year-old male who sustained a GSW to the anterior chest from a high velocity pellet rifle. The patient was reported to have been shot at close range leading lodging of the pellet in his chest. On arrival, his airway was intact and he was hemodynamically stable with a heart rate of 97 beats per minute, a blood pressure of 131/76 mmHg, and a respiratory rate of 18 on room air. Computed tomography (CT) scan in the emergency department showed hemopericardium and tamponade with a pellet along the undersurface of the heart appearing to lie within the pericardium as demonstrated in Fig. 1a and b. Additionally, there was a small hemothorax with lung injury seen near the entrance of the bullet in the anterior right middle lobe.

Fig. 1.

a. Axial cross sectional imaging of chest demonstrating metallic object within the pericardium as demonstrated by red arrow. b. Coronal cross sectional imaging redemonstrating metallic foreign object within pericardium as indicated by the blue arrow. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)

The patient was taken emergently to the operating room for a pericardial window. Intraoperatively, there was immediate expulsion of blood upon incision into the pericardium. Concerns regarding an epicardial injury along the right coronary artery (RCA) prompted conversion of the pericardial window to a median sternotomy. A clot was visualized on top of the right ventricle extending down to the diaphragmatic surface. While undergoing exploration, the patient experienced two episodes of ventricular fibrillation, requiring defibrillation to restore sinus rhythm. The clot was successfully evacuated and confirmed to contain the pellet. Additionally, hypokinesis of the right ventricle with a mid-RCA contusion was observed. Perioperatively, doppler imaging of the distal RCA showed satisfactory distal blood flow.

The patient remained sedated and intubated post procedure and was transferred to the cardiovascular intensive care unit in stable condition. On postoperative day (POD) 1, the patient was found to have elevated troponin at 3771 ng/L consistent with potential traumatic injury to the myocardium. Serial testing showed consistent doubling of subsequent values with ECG changes raising concern for an evolving inferior infarction. Transthoracic echocardiogram (TTE) revealed severely diminished right and left ventricular function. Following discussions with the cardiac, pediatric, and cardiothoracic surgery teams, the decision was made to take the patient urgently to the catheterization lab for percutaneous coronary intervention. Intraoperatively, the patient was found to have a middle RCA occlusion from a dissection flap that is demonstrated in image 2a. Two drug eluting stents (DES) were placed facilitating the restoration of flow to distal vessels, which can be seen in Fig. 2b and c.

Fig. 2.

a. Diagnostic coronary angiography demonstrating right coronary artery dissection (blue arrow). b. Immediately after deployment of the proximal drug eluding coronary stent. c. Completion angiography after placement of both drug eluding stents. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)

After the procedure, the patient remained intubated and sedated, and was subsequently transferred back to the ICU. Intravenous cangrelor was initiated, with plans to transition to oral administration of 90 mg ticagrelor twice daily upon extubation, for a duration of at least one year. Additionally, Aspirin 81 mg orally was prescribed indefinitely, as tolerated. Repeat TTE showed improved biventricular function. Patient was discharged on POD 8 with appropriate follow up precautions.

Discussion

PCI serves as a valid strategy for acute coronary thrombotic events. In literature this is mostly seen with children presenting with Kawasaki's disease, not in the setting of trauma and coronary dissection. Nevertheless, stenting has proved to successfully revascularize distal flow and reserve myocardial function [5]. The main risk in pediatric populations is addressing the risk of restenosis and stent thrombosis due to few objective findings on appropriate antiplatelet therapy. Most findings performed for antiplatelet dosing revolve around systemic-pulmonary artery shunts with prospective randomized data performed for only aspirin with preliminary studies on clopidogrel and dipyridamole [6]. Aspirin alone has proved to be sufficient in reducing restenosis/stent thrombosis with systemic-pulmonary artery shunts [7]. However, aspirin may not be sufficient for prevention of coronary artery restenosis/stent thrombosis due to its ability to block only 1 pathway of platelet activation. The use of clopidogrel at a dose of 0.20 mg/kg/d in the pediatric population has been illustrated to reduce the maximum extent and rate of platelet aggregation while concomitantly not increasing the risk of serious adverse bleeding events in the studied population [8].

There still remains no data on the actual effect of reducing restenosis/stent thrombosis with the use of clopidogrel. Further characterization of its utility must be studied to adequately improve stent patency while reducing risk of bleeding especially in the trauma population, such as this presentation. The presented case shows a unique and rare presentation of trauma induced coronary dissection requiring stent placement, illustrating the need for research on appropriate antiplatelet dosing and management in the pediatric population after PCI.

This case serves to illustrate the use of coronary stent implantation in a pediatric coronary dissection in the setting of a trauma, it also serves to point out a paucity of data on appropriate antiplatelet therapy dosage in the pediatric population.

CRediT authorship contribution statement

Vincent Marcucci: Writing – review & editing, Writing – original draft, Validation, Project administration, Methodology, Investigation, Formal analysis, Data curation, Conceptualization. Clement Rajakumar: Writing – review & editing, Writing – original draft, Methodology, Investigation. Emmanuel Ihionkhan: Writing – review & editing, Writing – original draft, Data curation. Joseph Moorman: Writing – review & editing, Writing – original draft. James Botta: Writing – review & editing, Supervision, Investigation. Victoriya Staab: Writing – review & editing, Supervision, Methodology, Investigation, Conceptualization.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.