All surgery is associated with risk. EVAR may be a minimally invasive (key hole) procedure, but it is associated with manipulation of the aorta and is therefore associated with a risk of significant complications. Complications of surgery can broadly be categorised according to when they occur (during the hospital admission - early or following discharge - late) and whether or not they occur at the site of surgery (local) or affect the entire body (systemic). Some possible complications of EVAR include: •Early complications: •Local oWound related - Bleeding - Infection - Wound breakdown - Fluid collection oInjury to surrounding structures - Nerve damage causing numbness, pain or weakness in the leg - Lymphatic leak causing leakage from the wound, collection or leg swelling oGraft complications: - Bleeding or blockage requiring re-operation. - Graft infection (rare) oBlood clot in leg (deep vein thrombosis) oLimb loss (very rare) •Systemic oImplantation Syndrome: Stentgrafts are essentially metallic structures covered in waterproof material. Occasionally the body mounts an inflammatory response to this foreign material much in the same way which a thumb would go red, swell and become hot at the site of a splinter. This, when following an EVAR, is on a larger scale and the patient might experience this as flu-like symptoms; high temperature, night sweats, fatigue etc. This is invariably self-resolving within a couple of weeks; the symptoms treated with over the counter medication such as paracetamol. On very rare occasions the symptoms can last for a couple of months. oHeart related - Heart attack - Irregular heart rhythm oLung related - Pneumonia - fluid on the lungs - Clot on the lung (pulmonary embolus) oKidney related - Kidney failure that may require temporary dialysis oBrain related - stroke •Late complications •Stentgraft blockage: oBlockage of (a limb of) the stentgraft is a rare occurrence. It is seen in 0-5% of EVAR cases. This may be precipitated by stentgraft kinking or narrowing/blockages of blood vessels upstream or downstream of the stentgraft. The indication for treatment depends on the severity of associated symptoms, the physical condition of the patient and the vascular anatomy. If possible, endovascular (key hole) procedures are used to restore blood flow through the graft e.g. angioplasty, although occasionally a surgical bypass operation may have to be carried out. •Endoleak oPersistent blood flow in the aneurysm sac after endovascular repair is defined as an endoleak and is considered a complication of the procedure as the primary objective of endovascular aneurysm repair is to exclude the aneurysm sack from the circulation. Depending on the nature of the endoleak, the persistent blood flow in the aneurysm sac means that the sac may still be pressurised and therefore continues to be at risk of rupture. Endoleaks caused by holes in the graft material, insufficient apposition of the stent graft against the aortic wall or disconnection of overlapping stent graft components require intervention in order to depressurize the aneurysm sac and mitigate the risk of rupture. These endoleaks may be related to, stentgraft material failure, graft migration or progression of aneurysmal disease. Lifelong surveillance is necessary to mitigate the risk associated with these endoleaks, which develop in as many as 20-40% of patients during long term follow-up. Alternatively, retrograde flow of blood through aortic side branches such as the lumbar arteries or the inferior mesenteric artery, into the aneurysm sack are innocuous and do not require any treatment in the majority of cases. All these potential complications are understandably concerning. Rest assured our surgeons make every effort to ensure your risk is reduced to the lowest level possible through our expertise and experience. The overall risk of you suffering from a major complication that either threatens your life or leg is about 2%. When complications do occur, we deal with them rapidly and appropriately.