Syncope (fainting on standing from squatting) due to massive venous reflux into lower limb varicose veins - Case report.

A 42-year-old man presented with very large lower limb varicose veins bilaterally and an 8-month history of fainting when standing up from a squatting position. He had been investigated for syncope by a cardiologist with no abnormality found on electrocardiogram, echocardiogram, 24-h electrocardiogram or 48-h blood pressure monitoring. Venous duplex ultrasonography showed bilaterally great saphenous vein reflux, with each vein having a diameter of 23.5 and 24.0 mm at the groin, and a similar dilation along the whole vein to ankle. These veins were successfully ablated with endovenous laser ablation, immediately following which the syncope disappeared and has not returned. We calculate that before treatment, the patient had approximately 500 ml of blood refluxing passively with gravity from his deep venous system on standing into his incompetent great saphenous veins and associated varicosities, which would account for his postural syncope.