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Axilloaxillary Arteriovenous Fistula Caused by Previous Penetrating Trauma
The Journal of Emergency Medicine, Vol. -, No. -, pp. 1–3, 2016 Published by Elsevier Inc. 0736-4679/$ - see front matter
http://dx.doi.org/10.1016/j.jemermed.2016.06.047
Clinical Communications: Adult AXILLOAXILLARY ARTERIOVENOUS FISTULA CAUSED BY PREVIOUS PENETRATING TRAUMA Brian Raffetto, MD, Neil Rifenbark, MD, and Ashokkumar Jain, MD Department of Emergency Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA Corresponding Address: Brian Raffetto, MD, Department of Emergency Medicine, Keck School of Medicine of the University of Southern California, 2051 Marengo Street, Inpatient Tower, Room C1A100, Los Angeles, CA 90033
, Abstract—Background: Traumatic axilloaxillary arteriovenous (AV) fistulas are rare occurrences, with the predominance of AV fistulas in this region occurring as an alternative surgical intervention in patients who are undergoing hemodialysis. Case Report: We describe the case of a young man with this condition caused by a previous penetrating trauma who had a delayed diagnosis primarily because of the infrequency of the clinical presentation. This is one of a few documented cases of axilloaxillary AV fistulas in the setting of trauma. Why Should an Emergency Physician be Aware of This?: Axilloaxillary AV fistulas present with loud machinery like cardiac murmurs that can be similar to patients with coarctation of the aorta and patent ductus arteriosus; however, important clinical examination features can help distinguish the two conditions. Diagnosis is important in avoiding late-stage complications and more technically difficult surgical repairs. Published by Elsevier Inc.
disease. AV fistulas have also rarely been noted in case reports as having been caused by penetrating trauma, such as gunshots or stabbings (1). We describe a 45-year-old man with distant history of a gunshot wound to the abdomen and left shoulder who presented with atypical chest pain and was discovered to have clinical findings that led to the diagnosis of an axilloaxillary AV fistula. CASE REPORT A 45-year-old man presented to our emergency department (ED) with the chief complaint of three discrete episodes of acute onset chest discomfort and air hunger. Symptoms occurred after eating and were associated with a warm sensation in the upper body and anxiety. Discomfort improved with ambulation. The patient did not have dyspnea on exertion or a recent decrease in exercise tolerance. The patient also denied a positional component. He had no recent infectious symptoms, such as a productive cough, abdominal pain, nausea or vomiting, or diarrhea, and denied any recent travel or leg pain or swelling. The patient was active and worked in construction without any difficulty. The initial vital signs included mild hypotension but were otherwise unremarkable. His medical history included a gunshot wound to the abdomen and left shoulder 18 years earlier that had been managed with an exploratory laparotomy of the abdomen. The patient had known retained bullet
, Keywords—complications; clinical examination; radiology; vascular injury
INTRODUCTION Axilloaxillary arteriovenous (AV) fistulas are connections between the axillary artery and vein. They are predominantly seen after an alternative surgical procedure for hemodialysis access in patients with end-stage renal
RECEIVED: 26 February 2016; FINAL SUBMISSION RECEIVED: 26 April 2016; ACCEPTED: 29 June 2016 1
2
B. Raffetto et al.
fragments in the left shoulder region. He was unaware of any medical problems or cardiac history. On initial assessment, the medical provider assessed delta troponin and beta natriuretic peptide levels and the patient received radiography of the chest; these tests were negative for acute pathology. The patient was noted to have low blood pressure (BP) but appeared clinically stable and was subsequently sent the ED observation unit (OU) for a cardiac stress test the next morning. Incidentally, upon further examination the OU provider discovered a loud machinery–like cardiac murmur that was loudest at the left upper sternal border and that radiated to the left upper scapula. An echocardiogram displayed no evidence of valvular disease or septal defects and had a normal ejection fraction. Given concern for vascular injury, computed tomography angiography of the chest was performed. While the differential included patent ductus arteriosus and aortic coarctation, the provider noted that the BP was higher in the lower extremities than in the upper extremities, which is the opposite of the typical clinical findings in the noted diagnoses. The initial computed tomography angiography scan did not identify any vascular injury, and the subsequent OU provider sent the patient home with return precautions and a plan to follow up with outpatient services. The OU provider called the patient back to the ED for further evaluation given that the cause of the machinery murmur was not identified. At that time, the patient was asymptomatic and denied any chest pain, dyspnea on exertion, or decrease in exercise tolerance. On examination, a loud machinery murmur persisted. Repeat blood pressures were as follows: left upper extremity 82/54 mm Hg; left lower extremity 142/62 mm Hg; right upper extremity 112/64 mm Hg; and right lower extremity 145/59 mm Hg. The ED provider contacted the radiology department to reexamine the computed tomography angiography scan of the chest to better assess for vascular injury of the left upper extremity. Upon closer inspection, a radiologist noted an axilloaxillary AV fistula with an adjacent pseudoaneurysm measuring 3.5 1.6 1.5 cm (Figure 1, Video 1). Because the patient was stable, the ED provider discharged the patient home with a plan for vascular surgery follow-up to determine the need for AV fistula repair. DISCUSSION Traumatic axilloaxillary AV fistula formation is a rare sequela of penetrating trauma. The symptoms are often subtle, which contributes to the low number of reported cases. Important clinical findings can help point providers in the direction of listing an axilloaxillary AV fistula as part of the differential. In our patient, a loud machinery–like murmur was present. A British case series found that while the classic machinery-like murmur may not be
Figure 1. Computed tomography angiography scan showing axilloaxillary arteriovenous fistula and pseudoaneurysm (labeled).
present early in the disease process, it is almost universal in patients presenting later in the disease process (1). Our patient also had lower BP in the affected extremity relative to his other extremities because of the shunting of blood flow created by the fistula itself. This helped distinguish an AV fistula from other congenital abnormalities. Although not present in our case, extremity edema and pronounced venous vasculature may also be present. Most surgeons have little experience with repair of a traumatic AV fistula between the axillary artery and vein. In addition, surgery is difficult because of the complex neuromuscular relationships in the subclavian region, with high rates of morbidity and mortality (2). Case reports have shown successful endovascular repair (3,4). WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS? Machinery cardiac murmurs are easily recognizable on cardiac auscultation and are the result of only a handful of physiologic causes. By performing a more extensive physical examination, the emergency physician can narrow the differential and better select the necessary radiologic workup required to determine the actual cause of the cardiac murmur and better understand the physiology. Fistulas must be considered in the differential of machinery murmurs, especially in patients with a history of penetrating trauma. It is important to diagnose traumatic AV fistulas early because late complications can lead to significant morbidity or even mortality. AV fistulas
Axilloaxillary AV Fistula Caused by Penetrating Trauma
have been associated with embolism, rupture, and highoutput heart failure (5,6). Early diagnosis also allows for a less technically challenging surgical intervention, because progressive dilation of the arterial results in a more complex repair. REFERENCES 1. Robbs JV, Carrim AA, Kadwa AM, Mars M. Traumatic arteriorvenous fistula: experience with 202 patients. Br J Surg 1994;81: 1296–9. 2. Chen JK, Johnson PT, Fishman EK. Diagnosis of clinically unsuspected posttraumatic arteriovenous fistula of the pelvis using CT angiography. AJR Am J Roetgenol 2007;188:W269–73.
3 3. Leong BD, Naresh G, Hanif H, Lee SK, Zainal AA, Sara CM. Endovascular management of axillosubclavian artery injuries: report of three cases. Surg Today 2013;43:918–22. 4. Mo A. Endovascular repair of traumatic arteriovenous fistula between axillary artery and vein. Chin J Traumatol 2014;17:112–4. 5. Stigall KE, Dorsey SD. Late complications of traumatic arteriovenous fistula: case report and overview. Am J Surg 1989;55:180–5. 6. Trindade VD, PiantP RM, Heck AA, Goldani MA. High-output heart failure resulting from a traumatic arteriovenous fistula. J Vasc Surg 2015;61:1329.
SUPPLEMENTARY DATA Supplementary data related to this article can be found at http://dx.doi.org/10.1016/j.jemermed.2016.06.047.
http://dx.doi.org/10.1016/j.jemermed.2016.06.047
Clinical Communications: Adult AXILLOAXILLARY ARTERIOVENOUS FISTULA CAUSED BY PREVIOUS PENETRATING TRAUMA Brian Raffetto, MD, Neil Rifenbark, MD, and Ashokkumar Jain, MD Department of Emergency Medicine, Keck School of Medicine of the University of Southern California, Los Angeles, CA Corresponding Address: Brian Raffetto, MD, Department of Emergency Medicine, Keck School of Medicine of the University of Southern California, 2051 Marengo Street, Inpatient Tower, Room C1A100, Los Angeles, CA 90033
, Abstract—Background: Traumatic axilloaxillary arteriovenous (AV) fistulas are rare occurrences, with the predominance of AV fistulas in this region occurring as an alternative surgical intervention in patients who are undergoing hemodialysis. Case Report: We describe the case of a young man with this condition caused by a previous penetrating trauma who had a delayed diagnosis primarily because of the infrequency of the clinical presentation. This is one of a few documented cases of axilloaxillary AV fistulas in the setting of trauma. Why Should an Emergency Physician be Aware of This?: Axilloaxillary AV fistulas present with loud machinery like cardiac murmurs that can be similar to patients with coarctation of the aorta and patent ductus arteriosus; however, important clinical examination features can help distinguish the two conditions. Diagnosis is important in avoiding late-stage complications and more technically difficult surgical repairs. Published by Elsevier Inc.
disease. AV fistulas have also rarely been noted in case reports as having been caused by penetrating trauma, such as gunshots or stabbings (1). We describe a 45-year-old man with distant history of a gunshot wound to the abdomen and left shoulder who presented with atypical chest pain and was discovered to have clinical findings that led to the diagnosis of an axilloaxillary AV fistula. CASE REPORT A 45-year-old man presented to our emergency department (ED) with the chief complaint of three discrete episodes of acute onset chest discomfort and air hunger. Symptoms occurred after eating and were associated with a warm sensation in the upper body and anxiety. Discomfort improved with ambulation. The patient did not have dyspnea on exertion or a recent decrease in exercise tolerance. The patient also denied a positional component. He had no recent infectious symptoms, such as a productive cough, abdominal pain, nausea or vomiting, or diarrhea, and denied any recent travel or leg pain or swelling. The patient was active and worked in construction without any difficulty. The initial vital signs included mild hypotension but were otherwise unremarkable. His medical history included a gunshot wound to the abdomen and left shoulder 18 years earlier that had been managed with an exploratory laparotomy of the abdomen. The patient had known retained bullet
, Keywords—complications; clinical examination; radiology; vascular injury
INTRODUCTION Axilloaxillary arteriovenous (AV) fistulas are connections between the axillary artery and vein. They are predominantly seen after an alternative surgical procedure for hemodialysis access in patients with end-stage renal
RECEIVED: 26 February 2016; FINAL SUBMISSION RECEIVED: 26 April 2016; ACCEPTED: 29 June 2016 1
2
B. Raffetto et al.
fragments in the left shoulder region. He was unaware of any medical problems or cardiac history. On initial assessment, the medical provider assessed delta troponin and beta natriuretic peptide levels and the patient received radiography of the chest; these tests were negative for acute pathology. The patient was noted to have low blood pressure (BP) but appeared clinically stable and was subsequently sent the ED observation unit (OU) for a cardiac stress test the next morning. Incidentally, upon further examination the OU provider discovered a loud machinery–like cardiac murmur that was loudest at the left upper sternal border and that radiated to the left upper scapula. An echocardiogram displayed no evidence of valvular disease or septal defects and had a normal ejection fraction. Given concern for vascular injury, computed tomography angiography of the chest was performed. While the differential included patent ductus arteriosus and aortic coarctation, the provider noted that the BP was higher in the lower extremities than in the upper extremities, which is the opposite of the typical clinical findings in the noted diagnoses. The initial computed tomography angiography scan did not identify any vascular injury, and the subsequent OU provider sent the patient home with return precautions and a plan to follow up with outpatient services. The OU provider called the patient back to the ED for further evaluation given that the cause of the machinery murmur was not identified. At that time, the patient was asymptomatic and denied any chest pain, dyspnea on exertion, or decrease in exercise tolerance. On examination, a loud machinery murmur persisted. Repeat blood pressures were as follows: left upper extremity 82/54 mm Hg; left lower extremity 142/62 mm Hg; right upper extremity 112/64 mm Hg; and right lower extremity 145/59 mm Hg. The ED provider contacted the radiology department to reexamine the computed tomography angiography scan of the chest to better assess for vascular injury of the left upper extremity. Upon closer inspection, a radiologist noted an axilloaxillary AV fistula with an adjacent pseudoaneurysm measuring 3.5 1.6 1.5 cm (Figure 1, Video 1). Because the patient was stable, the ED provider discharged the patient home with a plan for vascular surgery follow-up to determine the need for AV fistula repair. DISCUSSION Traumatic axilloaxillary AV fistula formation is a rare sequela of penetrating trauma. The symptoms are often subtle, which contributes to the low number of reported cases. Important clinical findings can help point providers in the direction of listing an axilloaxillary AV fistula as part of the differential. In our patient, a loud machinery–like murmur was present. A British case series found that while the classic machinery-like murmur may not be
Figure 1. Computed tomography angiography scan showing axilloaxillary arteriovenous fistula and pseudoaneurysm (labeled).
present early in the disease process, it is almost universal in patients presenting later in the disease process (1). Our patient also had lower BP in the affected extremity relative to his other extremities because of the shunting of blood flow created by the fistula itself. This helped distinguish an AV fistula from other congenital abnormalities. Although not present in our case, extremity edema and pronounced venous vasculature may also be present. Most surgeons have little experience with repair of a traumatic AV fistula between the axillary artery and vein. In addition, surgery is difficult because of the complex neuromuscular relationships in the subclavian region, with high rates of morbidity and mortality (2). Case reports have shown successful endovascular repair (3,4). WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS? Machinery cardiac murmurs are easily recognizable on cardiac auscultation and are the result of only a handful of physiologic causes. By performing a more extensive physical examination, the emergency physician can narrow the differential and better select the necessary radiologic workup required to determine the actual cause of the cardiac murmur and better understand the physiology. Fistulas must be considered in the differential of machinery murmurs, especially in patients with a history of penetrating trauma. It is important to diagnose traumatic AV fistulas early because late complications can lead to significant morbidity or even mortality. AV fistulas
Axilloaxillary AV Fistula Caused by Penetrating Trauma
have been associated with embolism, rupture, and highoutput heart failure (5,6). Early diagnosis also allows for a less technically challenging surgical intervention, because progressive dilation of the arterial results in a more complex repair. REFERENCES 1. Robbs JV, Carrim AA, Kadwa AM, Mars M. Traumatic arteriorvenous fistula: experience with 202 patients. Br J Surg 1994;81: 1296–9. 2. Chen JK, Johnson PT, Fishman EK. Diagnosis of clinically unsuspected posttraumatic arteriovenous fistula of the pelvis using CT angiography. AJR Am J Roetgenol 2007;188:W269–73.
3 3. Leong BD, Naresh G, Hanif H, Lee SK, Zainal AA, Sara CM. Endovascular management of axillosubclavian artery injuries: report of three cases. Surg Today 2013;43:918–22. 4. Mo A. Endovascular repair of traumatic arteriovenous fistula between axillary artery and vein. Chin J Traumatol 2014;17:112–4. 5. Stigall KE, Dorsey SD. Late complications of traumatic arteriovenous fistula: case report and overview. Am J Surg 1989;55:180–5. 6. Trindade VD, PiantP RM, Heck AA, Goldani MA. High-output heart failure resulting from a traumatic arteriovenous fistula. J Vasc Surg 2015;61:1329.
SUPPLEMENTARY DATA Supplementary data related to this article can be found at http://dx.doi.org/10.1016/j.jemermed.2016.06.047.