Life-Saving Management of Traumatic Coronary Artery Dissection and Acute Myocardial Infarction in a 21-Year-Old Motorcyclist: A Case Report

Introduction

Injuries to the heart are uncommonly observed in cases of blunt chest trauma. These can include various pathologies, such as myocardial contusion, myocardial rupture, and valvular rupture [1]. While coronary artery injury is a relatively rare cause of cardiac injury, it does occur [2]. The clinical symptoms of cardiac injury can vary considerably, from asymptomatic arrhythmia to acute myocardial infarction and sudden death [3]. Early recognition and prompt treatment are crucial for preventing tragic outcomes. This report describes a 21-year-old man with traumatic coronary artery dissection (TCAD) following a motorcycle accident, presenting with ventricular fibrillation (VF) due to acute myocardial infarction (MI), which was treated with percutaneous transluminal coronary angioplasty (PTCA) and extracorporeal membrane oxygenation (ECMO).

Case Report

A 21-year-old man with an unremarkable past medical history was admitted to the Emergency Department after a motor vehicle accident. He was found lying on the road, several meters away from his motor vehicle. Upon arrival, his vital signs were blood pressure of 112/82 mmHg, pulse of 96 beats per min, respiratory rate of 20 breaths per min, and O2 saturation of 95%. He was drowsy and confused, with a Glasgow Coma Scale score of E3V4M5. The anterior chest wall was abrased, and chest auscultation revealed rales, but there was no pericardial friction rub or heart murmur. The extended focused assessment with sonography of trauma was performed but was negative. Head and chest computed tomography (CT) revealed no apparent intracranial hemorrhage; however, the chest CT revealed bilateral pulmonary contusion injuries, with hemorrhage and without hemopneumothorax. After arriving back in his room after the CT scans, he collapsed and demonstrated cyanosis. He was emergently intubated, and VF was detected. Defibrillation was performed using biphasic 200-J shocks, and 1 mg of intravenous epinephrine and 300 mg of amiodarone were administered. He demonstrated a return of spontaneous circulation after 2 cycles of cardiopulmonary resuscitation. A 12-lead electrocardiogram (ECG) showed sinus tachycardia, with a hyperacute T wave and ST elevation in V2 to V6 (Figure 1). The echocardiography showed hypokinetic wall motion of the anterior septal and lateral segments of the left ventricle and no pericardial effusion. Despite receiving support from a mechanical ventilator and norepinephrine, the patient’s condition worsened, with low oxygen levels and shock symptoms, and with potential heart and lung failure. The patient immediately underwent intra-arteriovenous ECMO in the right femoral artery to address this. Subsequently, PTCA was performed, during which the doctor found dissection from the ostial to the proximal portion of the left anterior descending artery (LAD) (Figure 2, white arrows). A drug-eluting stent was inserted to enhance blood flow in the LAD artery, resulting in TIMI 2 flow restoration. The patient was admitted to the Intensive Care Unit after the procedure. While in the Intensive Care Unit, the patient experienced pulmonary hemorrhage accompanied by hemoptysis, which was treated with tranexamic acid and bronchoscopy. The patient’s left ventricular function subsequently improved, and he was successfully removed from ECMO on the fifth day. After spending 16 days in the hospital ward, the patient was discharged and was doing well during a follow-up clinic visit 3 months later.

Discussion

The clinical course of this patient with chest trauma consisted of acute MI manifested by sudden collapse due to VF. He was successfully rescued by the timely use of ECMO followed by PTCA, which proved TCAD, a rare but life-threatening complication of blunt cardiac injury. TCAD can result in intraluminal thrombosis and coronary occlusion, leading to acute coronary syndrome and ventricular arrhythmia [4]. Based on our literature review, this case is the first reported successful use of ECMO in a coronary artery dissection-induced cardiac arrest of traumatic origin.

There has been an increase in the frequency of discussions surrounding TCAD, suggesting that it may have been previously underdiagnosed or that its incidence is on the rise [5]. The most common causes of TCAD include high-speed motor vehicle collisions, direct blows to the chest wall, sports injuries, and falls [4]. TCAD is a type of coronary artery dissection that is usually caused by trauma. It is more common in men than women. The LAD coronary artery is the most commonly affected vessel, followed by the right and circumflex coronary arteries. In contrast, spontaneous coronary artery dissection predominantly affects women [7]. It can be challenging for physicians to recognize and diagnose coronary artery dissection early because the clinical manifestations are variable and can be overshadowed by concurrent thoracic injuries. The LAD is the coronary artery closest to the anterior chest wall, which can increase the likelihood of dissection in that area. Patients may not show any symptoms until ischemia and infarction develop, but common signs include angina-like chest pain and dysrhythmia, leading up to cardiac arrest [4,6]. Our patient collapsed due to VF. Associated thoracic injuries should raise concerns about blunt cardiac injury and coronary artery dissection [7,8].

Early detection of TACD in trauma patients can be achieved through troponin-I tests, ECGs, and echocardiography [4]. ECG can reveal acute MI with notable ST-segment abnormality or arrhythmia. Troponin-I elevation after chest trauma can indicate cardiac injury. Transthoracic echocardiography can show abnormal wall motion [9]. ECG, echocardiography, and blood biomarkers currently available, however, are not able to differentiate between coronary artery dissection and other causes of acute coronary syndrome.

A diagnosis of coronary artery dissection is typically made during coronary angiography. The typical angiography findings of coronary artery dissection can be divided into 3 types: type 1, which appears as multiple radiolucent lumens; type 2, which appears as long diffuse stenosis; and type 3, which mimics atherosclerosis [10]. In cases in which the diagnosis is not defined through coronary angiography, intracoronary imaging with optical coherence tomography or intravascular ultrasound can be helpful. Other methods have been described, including CT, coronary angiography, and cardiac magnetic resonance imaging [2].

The management of TCAD remains controversial due to its rarity and lack of long-term outcome data in the literature [3,11]. Antiplatelet agents are used with caution in the treatment of TCAD, due to concerns about worsening traumatic bleeding. The primary treatment approach is PTCA with or without stent implantation, which should be performed early in symptomatic patients. This approach effectively revascularizes the affected area and reverses ST elevations. Other treatment options, such as coronary artery bypass grafting, conservative therapy, and thrombolytic therapy, have also been reported to have good clinical outcomes [3,5]. The prognosis of TCAD is closely linked to the affected coronary segments, extent of myocardial damage, and effectiveness of treatment. Prompt recognition and appropriate management have yielded positive outcomes [2,11].

Compared with previously reported cases of TCAD, most cases were combined or resulted in obvious trauma injury [4,12,13]. Our patient had only a minor chest wall contusion and abrasion on physical examination, with relatively stable vital signs, but he sustained VF due to TCAD with sudden collapse in a short period after arrival. Following that, he developed cardiopulmonary failure, which was indicated by progressive hypoxia and cardiogenic shock. However, using ECMO in our patient allowed successful PTCA to be performed under relatively hemodynamically stable conditions. Although ECMO use with trauma patients remains controversial because of concerns about bleeding complications, it can be a lifesaving option as a transient treatment [14]. In some cases, resuscitation can require a combination of defibrillation, ECMO, PTCA, and other advanced trauma life support [15]. We expect that future improvements in materials and techniques will make ECMO easier and safer to manage, thus extending its application to severely traumatic patients.

Conclusions

This report has described a case with the rare association between blunt chest trauma and coronary artery dissection and has highlighted that coronary artery dissection can result in acute MI, which can become life-threatening VF. Tests of acute coronary syndrome can help detect the presence of TCAD. Early consideration of using ECMO in hemodynamically unstable conditions and PTCA could increase the likelihood of patient survival.