Abstract 4357469: Blunt Trauma Causing Thrombotic Occlusive Myocardial Infarction

Case Description: A 66-year-old female presented to the emergency department after a motor vehicle collision. She presented with acute left-sided, burning, chest pain without radiation, accompanied by dyspnea and nausea. Advanced Trauma Life Support (ATLS) was initiated, and the primary survey revealed no abnormalities. An anterior electrocardiogram (ECG) was obtained that showed hyperacute T-waves in lead III, ST depression with T-wave inversion in aVL, and ST depression in V2, making STEMI the likely diagnosis (Fig 1). A chest X-ray demonstrated mediastinal enlargement raising concern for traumatic aortic dissection involving the coronaries (Fig 2a). After discussion with the institutional Heart Attack Team, a CT scan with arterial contrast was obtained revealing a right coronary artery occlusion without dissection or other trauma (Figure 2b). The patient went for emergent catheterization 37 minutes after arrival and was found to have a completely occluded mid-right coronary artery with TIMI-0 flow distally (Fig 3). Subsequent deployment of a drug-eluting stent with dilation restored TIMI-3 flow. A post procedural echocardiogram showed a left ventricular ejection fraction of 45% with mild right ventricular hypokinesis. On hospital day six, the patient was discharged chest pain free with outpatient cardiac rehabilitation scheduled. Discussion: This case describes a traumatic myocardial infarction (TMI) from thrombosis of the right coronary artery. TMIs are rare but are most described after severe blunt trauma causing coronary artery dissection. This patient, however, likely had intraluminal thrombosis secondary to an intimal tear of the coronary arteries from shear force, dislodgement of a plaque, or vascular spasm. Our case of an older patient with a right coronary artery occlusion represents a relatively uncommon TMI presentation, as TMI typically occurs in younger individuals and usually involves the left coronary artery. Chest pain after trauma has a wide differential, so a thorough assessment using ATLS principles is necessary. Presentation of TMI is greatly variable, having been described as resembling myocardial contusion, intracoronary intramural hematoma, and dissection. Management can differ with percutaneous coronary intervention, coronary artery bypass grafting, or conservative management. TMI as a complex, life-threatening clinical entity requiring complex multidisciplinary management.