femoro-popliteal bypass
What is the superficial femoral artery for?
The superficial femoral artery is the main feeder artery of the leg. It originates at the level of the fold of the groin from the femoral artery and extends at the level of the knee by the popliteal artery.
In the majority of cases, when an artery becomes stenotic (narrows) the supply network gradually develops and ensures normal oxygenation of the leg. During an effort (walking, running), the muscular needs increase and require an additional blood supply which cannot be provided when the artery is narrowed or clogged.
What lesion is causing the narrowing of the artery?
Atheromatous disease is the cause of the vast majority of femoral lesions. Atheromatous plaque consists of an accumulation in the wall of the artery of lipids (fats), carbohydrates (sugars), fibrous tissues and calcareous deposits. This plaque can be complicated by fracturing inside the artery which can lead to either an embolism or an occlusion of the artery. These atheromatous plaques develop especially at the level of the bifurcations due to the turbulence of the blood flow. Atheromatous disease is favored by cardiovascular risk factors: tobacco, high blood pressure, lipid abnormalities (cholesterol), diabetes.
How is damage to the superficial femoral artery manifested?
The clinical manifestations grouped under the term arteritis are related to the degree of narrowing of the artery and are classified into two stages of increasing severity:
Exertion pain: cramp-like pain or feeling of fatigue in certain muscle groups (calf, foot), triggered by physical exercise and disappearing at rest. This pain occurs when walking, never when resting or standing. It can also be a feeling of tightness, twisting, burning or a simple numbness of the limb. The distance traveled before the onset of pain (walking distance) can vary from less than 50 meters to more than 500 meters and is a good index of severity and monitoring of arteritis.
Rest pain: intense night pain, often intolerable, in the extremities (toes, feet) that are cold. These pains force the patient to get up or to let his legs hang out of bed and then give way very gradually. They reflect a more advanced degree of the disease and require urgent medical advice before the onset of wounds or gangrene.
What are the modalities of the surgery?
The operation is performed under general anesthesia or under loco-regional anesthesia. The Anesthesiologist will tell you the terms, the advantages and the risks of the chosen technique.
The basic procedure is the femoral-popliteal vein or prosthetic bypass. It consists of bypassing the pathological artery segment either by a prosthetic tube (Dacron, Goretex) or by a superficial vein (saphenous vein). This intervention requires at least two incisions: the first located at the level of the groin allows to connect the prosthesis or the vein to the femoral artery, the second above or below the knee is used for the connection (anastomosis) at the level of the popliteal artery. In the case of vein bypasses, several additional incisions on the thigh are generally necessary to ligate the branches of the vein
The duration of hospitalization varies from 5 to 10 days. Postoperative care is limited to dressings and subcutaneous injections of anticoagulant. On discharge, anti-platelet or anticoagulant treatment is started. You will be seen again in consultation by your Surgeon one month after your discharge from the service, then in the 3rd and 6th month by your Specialist Doctor for a control Echo-Doppler.
What are the possible incidents and accidents during the intervention?
Despite all the care taken, incidents or accidents may occur during the intervention in rare cases, most of which are immediately identified and dealt with. It could be :
Haemorrhage from arterial or venous injury. The transfusion of blood products remains exceptional during this type of intervention.
Nerve damage. In the majority of cases, it is a nervous contusion responsible for temporary disorders. Involvement of the femoral sensory nerves is frequent and results in an area of insensitivity or pain in the type of electric shocks on the anterior or internal face of the thigh. Pain generally subsides quickly, but sensory disturbances may persist for several months
Anesthesia accidents, exceptional. Specific information will be given to you by the doctor during the preoperative consultation.
What complications can occur after the procedure?
Specific complications may appear in the immediate postoperative period.
Hematoma favored by the use of anticoagulants and frequent flare-ups of high blood pressure. It results in painful swelling. If it is significant, it may require reoperation.
Lymphatic complications are seen at the level of the fold of the groin. It may be an effusion of lymph (lymphorrea) or swelling (lymphocele). If this flow does not dry up spontaneously, it may be preferable to intervene again to ligate the lymphatic vessels responsible. Phlebitis and pulmonary embolism are exceptional and are subject to systematic prevention during hospitalization (anticoagulant, early rising).
Infection, more common if the bypass is performed to treat a wound or the onset of gangrene. It can be superficial or deep. Dreadful in the event of prosthetic bypass, it then imposes a reoperation with removal of the prosthesis and realization of a venous bypass.
Thrombosis (obstructed bypass) can occur either immediately after surgery or during hospitalization. It most often reflects a technical problem (poor quality vein, recipient artery too damaged, etc.) and requires immediate reoperation. When a new bypass is not technically feasible, the evolution of the arteritis can be unfavorable with the appearance of unbearable pain and gangrene, which raises the question of the need for amputation.
Remotely, the results of these interventions are satisfactory with an average patency of 70% at five years, at the cost of regular monitoring in order to detect any progressive degradation of the "connection" zones between the bypass and the arteries .
Is there an alternative to surgical treatment?
In any case, before considering surgery, it is imperative to consult your Doctor who will guide you to a specialist Doctor (Angiologist, Cardiologist) for the realization of an echo-Doppler examination. Medical treatment should be systematically initiated and continued, either alone or in combination with surgery.
The fight against "vascular risk factors" by lifestyle and dietary measures (regular walking, quitting smoking, diet).
Drugs:
Vasodilators: studies have demonstrated an improvement of around 50% in walking distance. Their effectiveness on the long-term course of the disease is disputed.
Anti-platelet aggregants (Aspirin, Ticlid, Plavix and derivatives) have proven their effectiveness especially in terms of prevention of the occurrence of secondary cardiovascular accidents (25% risk reduction).
Surgical treatment is only proposed in the event of marked functional impairment or at the stage of rest pain or wounds.