What is peripheral occlusive arteriopathies (POA)?
Arteries to the rest of the body to nourish it. The inside of the lumen of the arteries is smooth to allow the unhindered flow of blood. Over time, however, their inner wall can become thick and irregular from deposits of materials such as cholesterol, calcium, damaged cells and fibrous tissue. This occurs mainly at the points where the arteries branch. These deposits form the so-called atherosclerotic plaque. This disease is known to everyone as atherosclerosis.
Over time, a sufficient amount of plaque gradually accumulates, which narrows or blocks the vessels, resulting in reduced blood flow and, by extension, the supply of oxygen to the tissues. This condition, which mainly affects the arteries of the lower extremities, is called peripheral occlusive arterial disease (PAD) or peripheral vascular disease (PAD).
Usually the disease progresses slowly and it takes a long time for symptoms to worsen when they do appear because the body develops collateral pathways in its attempt to maintain good blood flow to the tissues.
Sometimes, however, an atherosclerotic plaque can become complicated and partially rupture due to internal bleeding. This results in the immediate deposition of new clots on it, resulting in a rapid worsening of the stenosis or even complete occlusion, leading to an exacerbation of symptoms and critical ischemia.
What are the risk factors for Peripheral Occlusive Arteriopathies?
The main risk factors for RA coincide with those that cause, increase and maintain atherosclerosis. Smoking , is the main one that not only causes and worsens atherosclerotic plaque, but also reduces the prognosis of any surgical attempt if it continues postoperatively. Additional risk factors are diabetes arterialhypertension ,high cholesterol, obesity, increased uric acid and a family history of RA, ischemic stroke or heart attack. It should also be noted that RA affects older people (usually over 60 years of age). In Western societies, approximately one in four to five people over 70 years of age suffers from RA, with men experiencing the disease more often than women.
It is obvious that smoking cessation, regular monitoring and corresponding treatment of diabetes, blood pressure, cholesterol and uric acid, as well as a healthy lifestyle with a balanced diet and physical exercise significantly prevent the onset and progression of the disease.
What are the symptoms of Peripheral Occlusive Arteropathy?
PAD can remain asymptomatic for a long time. The first symptom that usually appears is the so-called intermittent claudication. In other words, it is a pain that appears after a few steps of walking in the buttocks, thighs, calves or feet depending on where the stenosis/obstruction is located and forces the patient to stop. After a short break of a few minutes, the pain disappears and the patient can continue walking again until the next few-minute rest stop. For this characteristic, this disease is also called “window dressing disease”, because sufferers who walked in the markets tried to hide this “disability” of theirs by stopping in the shop windows to look at them.
When the disease progresses, pain occurs after a few steps or even at rest in the calf and foot/toe area, mainly during the night. It is not uncommon for the patient to hang their leg from the bed in order to alleviate the pain and sleep.
begin to occur trophic disorders in the lower extremities, resulting in chronic ulcers and gangrene. In these cases, the possibility of the patient losing part of the lower limb is quite high.
Special mention should be made of patients with PAD in whom diabetes mellitus coexists. Here the prognosis of the disease is worse and its progression is faster. One of the reasons is that patients with chronic diabetes, in addition to alterations in the microcirculation of the vessels, also present degenerative alterations of the peripheral nerves , resulting in a reduction or even absence of sensation in the extremities and the sensation of pain (peripheral neuropathy). In advanced PAD, when external pressure is exerted by tight shoes or after microtraumas, the lack of blood flow causes chronic ulcers or even gangrene with a high risk of infection that are difficult to treat even after reperfusion. The above description, together with certain complex structural alterations in the bones of the foot, also constitute the clinical picture of the diabetic foot.
How is Peripheral Occlusive Arteriopathies diagnosed?
Taking a very good history – as in all diseases – is crucial for the diagnosis of PAD. This is because often the pain in the lower extremities is attributed to musculoskeletal or neurological pain (sciatica) and the patient does not immediately seek medical attention. It is then important to investigate and control the risk factors and to properly guide the patient not only for PAD but also for the risk of suffering from carotid and/or coronary artery disease.
This is followed by the necessary clinical examination with inspection of the lower extremities, palpation of the pulses and measurement of the malleolar pressure index , which is nothing more than measuring the systolic pressure in the lower extremities, depending on the “high” pressure that we measure in our arm, and comparing it with it. Ideally, their values should be the same or have a small difference. This measurement is done at rest and, if necessary, after a walking test to the pain threshold.
In case the above tests lead us to suspect the existence of PAA, the next stage is a color flow ultrasound (triplex) in which abnormalities in the structure and width of the vessels can be highlighted as well as the speed of blood flow within them can be measured, giving us a very reliable picture of the degree of stenosis or the extent of the obstruction.
If the clinical picture and the above tests make it necessary to plan a treatment, then the next step is a CT, MRI or digital angiography, depending on the ultrasound finding. In all of them, the administration of contrast medium is necessary (the contrast medium of magnetic angiography is not nephrotoxic like in the other two). Digital angiography, which is invasive since it is usually done by puncture of the femoral artery and administration of contrast medium through it, offers the advantage beyond diagnosis and immediate treatment, if this is possible with a balloon or stent.
What is the treatment for Peripheral Occlusive Arteriopathies?
The treatment of APA is multifaceted and can be purely endovascular (balloons, stents), purely open surgery (endarterectomy, bypass) or combine both methods, which is called a hybrid approach (see treatment).