Unilateral jugular vein stenosis in five horses and experience with percutaneous transluminal angioplasty

Background Venous stenosis, a possible cause of jugular dilatation and congestion, is well known in human medicine but has poorly been described in horses. Objective To report unilateral jugular vein stenosis as a cause of jugular vein dilatation in horses and describe treatment by percutaneous transluminal angioplasty (PTA). Study design Case report. Methods Details of horses diagnosed with unilateral jugular stenosis were retrieved from medical records. Results Five horses were presented with a non-painful, unilateral dilatation of the jugular vein of which two horses showed headshaking during exercise. In one horse an indwelling catheter had been used and jugular dilatation developed 4 weeks later. In the other horses, no intravenous injections had been administered in the months before jugular dilatation developed. Ultrasonographic examination revealed venous stenosis in all horses approximately 5-10 cm cranial to the thoracic inlet. The internal diameter at the level of this stenosis was only 1-3.1 mm. The length of the stenosis was about 15-19 mm with a markedly thickened intima and media on ultrasonography. After enoxaparin treatment, PTA was performed in three horses. During the procedure the stenotic vein was dilated three times with progressively increasing pressures up to 12 atm. The stenotic diameter increased to a maximum of 4.9 mm with improved jugular blood flow. Aftercare included anti-inflammatory and anti-thrombotic therapy. Conclusion Jugular vein stenosis occurs in horses and should be included in the differential diagnoses of unilateral jugular vein dilatation. It may present in the absence of previous intravenous treatment. PTA of the jugular vein is feasible to improve jugular blood flow.