Discussion
The majority of coronary artery fistulae are asymptomatic as they are hemodynamically not significant and are incidentally identified by coronary angiography, CT angiogram, echocardiogram or multi-detector row computed tomography (MDCT) with 3D reconstruction.[4]. Penetrating chest injuries causing coronary artery fistula are rare [5]. Moreover, presentation of patients may differ from lack of symptoms to heart failure or pulmonary hypertension [6,7]. However, most fistulas are hemodynamically non-significant with CT angiogram, echocardiogram or multi-detector row computed tomography (MDCT) as a diagnostic method [4]. We presented the first case of nail gun injury to the left ventricle with the coronary artery fistula to the left pulmonary artery presenting with unstable angina presenting after 4 years of asymptomatic course.
PubMed database was reviewed for relevant English literature from 1980 to 2020 using the keywords “nail gun”, “coronary artery fistula”, and “cardiac trauma”. Twenty-three cases of nail gun injury to the heart were found, with right chambers most commonly involved as penetration site (Table 1.). Unlike our patient, most cases presented acutely and required urgent surgical removal of the nail. Chest x-ray, CT, intraoperative transesophageal echocardiogram were used as modality of choice for diagnosis of patients and guidance throughout the management plan. However, due to the presentation of our patients with unstable angina and his chronic presentation, we decided to do a coronary angiogram which revealed abnormal vascular mesh between the right coronary artery and the left pulmonary artery.
Treatment approach depends on the case presentation; either the thoracotomy or median sternotomy are acceptable. However, the choice is mainly guided by the hemodynamic status and the location of the penetration. There are few cases in which both median sternotomy and CPB that has the advantage of providing a controlled field that allows for manipulation and movement of the heart without the risk of circulatory compromisation or arrhythmia. In this case We used CPB with median sternotomy without cardioplegia.
Traumatic coronary artery fistulae due to penetrating chest injuries are rare . Patients may present with congestive heart failure, pulmonary hypertension, or endocarditis. However, most patients may stay asymptomatic [6,7]. Treatment options for symptomatic patients may include (1) surgical correction with ligation of feeding vessels of the the coronary artery fistula [8] with or without bypass grafting of the distal vessel, (2) percutaneous closure either with coil embolization, or covered stent [9]. However, there are currently no well-designed guidelines for deciding whether and how to treat a coronary-pulmonary artery fistula.