True Aneurysm of the Proximal Brachial Artery

Abstract

A 35-year-old farmer presented with complaints of pain in the right upper limb for 1 month and bluish discoloration of the right-hand finger tips with tingling and numbness. He sustained injury to the right upper limb while lifting a heavy object 1 mo previously. There was an ovoid swelling of 4 × 2 cm on the medial aspect of the right arm, 12 cm above the medial epicondyle at the level of the armpit with visible pulsations. There was distal neurovascular deficit. Duplex scan of the right upper limb arterial system revealed a pseudoaneurysm of the proximal right brachial artery, with dampened monophasic flow in the ulnar artery and no flow in the radial artery. Spiral computed tomography angiogram showed the presence of an echogenic periarterial lesion in the proximal brachial artery suggestive of pseudoaneurysm or an extrinsic compression by hematoma. Distal brachial artery was found to have filled with thrombus, with non-opacification of the radial and the distal ulnar artery. The patient was posted for excision of the aneurysmal arterial segment. A 5-cm-long reversed segment of vein graft was interposed in between the cut ends of the brachial artery. Histopathology: Specimen shows a part of the vessel wall composed of intimal, medial, and adventitial layers with intraluminal thrombus showing evidence of recanalization suggestive of true aneurysm of the brachial artery.

Key Words

Brachial artery - True aneurysm

Introduction

A 35-year-old farmer presented to the hospital with complaints of pain in the right upper limb for 1 month and difficulty in lifting heavy weights with that arm. He noticed bluish discoloration of the finger tips of the right arm, with tingling and numbness for 2 days. He had sustained an injury to the right upper limb while lifting a heavy object 1 month previously. He is a nondiabetic, normotensive, chronic smoker, consuming 1-2 packs of cigarettes per day for the last 12 years. He was evaluated by his local doctor and found to have right upper limb ischemia.

Case History

Examination

There was an ovoid 4 × 2 cm swelling on the medial aspect of the right arm, 12 cm above the medial epicondyle, at the level of the armpit, with visible pulsations. Palpation revealed a nontender, pulsatile, nonfluctuant mass, noncompressible, nonreducible, not attached to the overlying skin or underlying muscles or bone. The mass was more mobile in the longitudinal plane than in the transverse plane. There were no palpable axillary or supraclavicular lymph nodes on either side. There was distal neurovascular deficit. No bruit was audible over the swelling. Examination of the precordium revealed no extra heart sounds or murmurs suggestive of valvular heart disease.

Imaging Studies

Duplex scan of the right upper limb arterial system revealed a pseudoaneurysm of the proximal right brachial artery, with dampened monophasic flow in the ulnar artery and no flow in the radial artery.

Spiral CT angiogram ([Fig. 1]) showed the presence of an echogenic periarterial lesion in the proximal brachial artery suggestive of pseudoaneurysm or an extrinsic compression by hematoma. The distal brachial artery was found to have filled with thrombus with non-opacification of the radial and the distal ulnar artery. The proximal ulnar artery showed patchy contrast uptake.

Figure 1. Spiral computed tomography angiogram of both the upper limbs. Note defect in right brachial artery.

Segmental blood pressure by hand-held Doppler detected 82 mm Hg pressure in the above-elbow segment of the brachial artery and nondetectable pressure in the below-elbow segment of the artery.

The patient was posted for excision of the aneurysmal arterial segment with interposition vein graft and distal brachial artery embolectomy.

Operative Management

The patient was placed in the supine position with abducted right upper limb under general anesthesia. A “lazy S” incision was made over the axilla. The aneurysm of the brachial artery was isolated with proximal and distal brachial artery control. The aneurysm was excised. A 5-cm-long reversed segment of vein graft was interposed between the cut ends of the brachial artery ([Fig. 2]).

Figure 2. Perioperative photographs.

The right limb was found to be warm with good capillary filling. The patient had relief of pain and numbness. The radial and ulnar arteries had palpable distal pulses. The biopsy sample revealed true aneurysm of the brachial artery with mural thrombus within.

Histopathology

Specimen shows a part of the vessel wall composed of intimal, medial, and adventitial layers with intraluminal thrombus, showing evidence of recanalization suggestive of true aneurysm of the brachial artery ([Fig. 3]).

Figure 3. Labeled histopathological section showing adventitial layer (a), intimal layer (i), medial layer (m), and intraluminal thrombus (t) showing evidence of recanalization.

Discussion

Brachial artery aneurysms are relatively rare compared to lower extremity aneurysms[1] [2] [3]. Most of these are pseudoaneurysms caused by trauma, including iatrogenic trauma, and drug abuse[4] [5]. True aneurysms are even rarer entities and can occur in infantile or older age groups[6]. Etiology consists of congenital connective tissue abnormalities, Kawasaki's syndrome, Buerger's disease, or repetitive trauma, and may be idiopathic[4]. Patients can be asymptomatic or present with pulsatile mass or ischemia due to thromboembolic complications (as in our patient)[4]. Distal embolism can occur with transient or minimal ischemic symptoms, or the aneurysm itself can thrombose entirely[7]. The natural history of brachial artery aneurysm is not well defined, and vascular repair is the main treatment option[4] [5]. Although endovascular techniques have been used to manage these patients (mainly for pseudoaneurysms), most true brachial artery aneurysm cases have been repaired by open surgery[1] [4].

• References

• 1 Gray RJ, Stone WM, Fowl RJ, Cherry KJ, Bower TC. Management of true aneurysms distal to the axillary artery. J Vasc Surg 1998; 28: 606-610 . 10.1016/S0741-5214(98)70083-7
• 2 Tetik O, Ozcem B, Calli AO, Gurbuz A. True brachial artery aneurysm. Tex Heart Inst J 2010; 37: 618-619
• 3 Schunn CD, Sullivan TM. Brachial arteriomegaly and true aneurysmal degeneration: case report and literature review. Vasc Med 2002; 7: 25-27 . 10.1191/1358863x02vm411cr
• 4 Timaran CH. Upper extremity aneurysms. In: Cronenwett JL, Johnston KW. eds. Rutherford's Vascular Surgery. , 7th edition. Philadelphia: Saunders Elsevier; 2010: 2138-2139
• 5 Hudorović N, Lovričević I, Franjić DB, Brkić P, Tomas D. True aneurysm of brachial artery. Wien Klin Wochenschr 2010; 122: 588-591 . 10.1007/s00508-010-1425-y
• 6 Bahcivan M, Yuksel A. Idiopathic true brachial artery aneurysm in a nine-month infant. Interact Cardiovasc Thorac Surg 2009; 8: 162-163
• 7 Fann JI, Wyatt J, Frazier RL, Cahill JL. Symptomatic brachial artery aneurysm in a child. J Pediatr Surg 1994; 29: 1521-1523 . 10.1016/0022-3468(94)90201-1