introduction to the Topic:
History of endovascular surgery
Cardiovascular disease is a major cause of mortality in the developed world since the beginning of the twenty-first century(1) .Although surgical revascularization has played an important role in the management of patients with vascular disease, the modern treatments have evolved significantly(1). The role of minimally invasive vascular intervention is different by various factors, including rapid advances in imaging technology, reduced morbidity, and mortality in endovascular interventions(1). The discovery of the X-ray imaging system by Charles Rentgen in 1895, marked one of the most remarkable milestones in the history of medicine. As a natural evolution of this discovery(1) . in 1919 Heuser performing the first contrast study in humans by injecting a solution of potassium iodide into the dorsal vein of a child and following the flow of the substance to the heart. The use of such materials was initially quite toxic. The modern aortogram via a femoral approach was first performed by Farinas in 1941,a technique that was quickly adapted by physicians around the world(1). With the advent of guidewires in the early 1950s, selective angiography with catheter-directed injection was developed further(1). In 1962, Guzman and colleagues reported a large series of patients who underwent coronary angiography using selective coronary catheterizations. Since then, the application of guidewires, catheters, and introducer sheaths has become a standard approach when performing diagnostic angiography (1). Ivar Seldinger, a Swedish radiologist, was the first physician to describe a unique method of establishing arterial access using a guidewire technique in 1953, which heralded an evolution from diagnostic to therapeutic angiography(1). A decade later, Fogarty detailed the use of a balloon-tipped catheter to extract thrombus. Building on this, Dotter and Judkin in 1964 described a method of dilating an arterial occlusion using a rigid Teflon catheter to improve the arterial circulation(1). The technique of balloon angioplasty was introduced by Gruntzig, who performed the first coronary artery intervention in 1974. To this day, this remains the most commonly performed endovascular procedure in clinical practice(1). The application of the balloon angioplasty catheter subsequently led to the development of the first intravascular balloon-expandable stent by Palmaz et al(1). in 1985. Technology in this field is rapidly evolving and more complex modular stents with thermal memory are in use today. There has also been an explosion in catheter-based technology, enabling access for the interventionalist to treat occlusive disease and increasingly, aneurysmal disease in nearly every vascular bed. Further development of this minimally invasive intervention is currently focused on combining a pharmacological agent with the current stent platform to create drug-eluting stents to improve the clinical outcome of endovascular therapy(1).
Common devices used in endovascular interventions:
Guidewires come in different maximum transverse diameters ranging from 0.011 to 0.038 in. For most aortoilliac procedures, a 0.035 wire is most commonly used. In addition to diameter size, guidewires come in varying lengths usually ranging from 180 to 260 cm in length(1).
Catheters come in all different shapes and sizes and are sized according to their outer diameters. Most catheters must be advanced over a wire to limit intimal injury. Catheters are generally differentiated based on whether they are nonselective or selective. A commonly used selective catheter is the Bernstein catheter, which has a gentle angled tip and can be used to select many arterial branches.Most other nonselective catheters have unique functions by design. In order to cannulate the contralateral iliac artery, we often use the Contra catheter(1).
3- Introducer sheath, guiding sheaths, and guiding catheters Vascular
sheaths allow for easy exchange and introduction of catheters and guidewires. They have a hemostatic valve that prevents blood reflux and air embolism(1).
4- Balloon catheters
Once the diseased arterial bed has been selected with the appropriate catheter and wire, the presence of the anticipated lesion needs to be confirmed, and where appropriate, its hemodynamic significance determined.An arteriogram is obtained by hand injection of contrast agent through the selective catheter, and a “road map” is acquired that creates a virtual image of the effected arterial segment through which repeated passes of catheters, wires, or stents can be visualized(1).
Vascular stents are commonly used after an inadequate angioplasty with dissection or elastic recoil of an arterial stenosis(1).
Normal anatomy of the lower limb arteries and the development of collateral circulation:
The average man has approximately five to six litres of blood in his body while The average women has approximately four to five litres of blood in her body . This blood is carried by several different types of blood vessels, each of which are specialized to play their role in circulating blood around the body(2). There are three major types of vessels; arteries, veins and capillaries. Arteries (deliver oxygenated blood to the tissues. At the tissues, the oxygen and nutrient exchange is done by the capillaries. The capillaries also return deoxygenated blood to the veins, which bring it back to the heart (with the exception of the pulmonary veins).(see fig 1.0)(2).
Fig 1.0 – Overview of the vessels involved in blood circulation.
Femoral Artery: see (Fig1.1).
The common femoral artery is the continuation of the external iliac artery at the level of the inguinal ligament (terminal branch of the abdominal aorta)(3). This artery supplying oxygenated blood to the leg, it gives smaller branches to the anterior abdominal wall. The femoral artery lies medial to the midpoint of the inguinal ligament, between the anterior superior iliac spine and symphysis pubis(3). The femoral vein lies medially within the femoral sheath. femoral nerve lies Lateral but outside the sheath . The common femoral artery terminates as it passes through the adductor hiatus in adductor magnus to become the popliteal artery(see fig1.2)(3). regarding the branches of this artery include of following:
– superficial epigastric artery.
– superficial circumflex iliac artery.
– superficial external pudendal artery.
And the terminal branches include:
– profunda femoris.
– superficial femoral artery.
These three vessels are encountered in the groin incision for repair foran inguinal hernia. Their corresponding veins drain into the great saphenous vein. The function of this artery is supply: lower limb, superficial pelvis and anterior abdominal wall(3).
The superficial femoral artery is a continuation of the common femoral artery at the point where the profunda femoris branches(3). It is the main artery of the lower limb and is, therefore, critical in the supply of oxygenated blood to the leg(3). In the femoral triangle, the profunda femoris artery (also known as the deep femoral artery or deep artery of thigh) is a branch of the common femoral artery arises from the posterolateral aspect of the femoral artery. It is responsible for providing oxygenated blood to the deep structures of the thigh, including the femora. It travels posteriorly and distally, giving off three main branches:
– Perforating branches – Consists of three or four arteries that perforate the adductor magnus, contributing to the supply of the muscles in the medial and posterior thigh.
– Lateral femoral circumflex artery – Wraps round the anterior, lateral side of the femur, supplying some of the muscles on the lateral aspect of the thigh.(3)
– Medial femoral circumflex artery – Wraps round the posterior side of the femur, supplying its neck and head. In a fracture of the femoral neck this artery can easily be damaged, and avascular necrosis of the femur head can occur(3).
The descending geniculate artery arises from the distal portion of the superficial femoral artery before it becomes the popliteal artery. Along with other arterial branches, it provides blood to the patella network and the knee (see Fig 1.3) (3).
Other Arteries of the Thigh:
The obturator artery arises from the internal iliac artery in the pelvic area(see Fig 1.4). It descends via the obturator canal to enter the medial thigh, bifurcating into two branches(2):
– Anterior branch – This supplies the pectineus, obturator externus, adductor muscles and gracilis (2).
– Posterior branch – This supplies some of the deep gluteal muscles.
The gluteal region is largely supplied by the superior and inferior gluteal arteries. These arteries entering the gluteal region via the greater sciatic foramen(2).
The popliteal artery continues on from the femoral artery at the adductor hiatus and terminates at the lower border of the popliteus muscle(see 1.5). It lies deep within the popliteal fossa , being covered superficially by the popliteal vein and, more superficially still, crossed by the tibial nerve. At the lower border of the popliteus, the popliteal artery terminates by dividing into the anterior tibial artery and the tibioperoneal trunk. The tibioperoneal trunk then divides into the posterior tibial and fibular arteries(2).
In the Foot:
two arteries supply the foot is delivered via (see Fig 1.6):
1- Dorsalis pedis (a continuation of the anterior tibial artery)
2- Posterior tibial artery.
The dorsal pedis artery begins as the anterior tibial artery enters the foot. It passes over the dorsal aspect of the tarsal bones, then moves inferiorly, towards the sole of the foot. It then anastamoses with the lateral plantar artery to form the deep plantar arch. The dorsalis pedis artery supplies the tarsal bones and the dorsal aspect of the metatarsals. Via the deep plantar arch, it also contributes to the supply of the toes(2).
The posterior tibial artery enters the sole of the foot through the tarsal tunnel. It then splits into the lateral and medial plantar arteries. These arteries supply the plantar side of the foot, and contributes to the supply of the toes via the deep plantar arch(2).