Synonyms
Diagnostics pAVK, examination for peripheral arterial occlusive disease, Ratschow storage test
Diagnosis
At the beginning the doctor asks for the patient’s medical history (anamnesis). The walking distance that can still be covered without pain is particularly important here. This is of particular importance for the stage classification of pAVK (see stage classification according to Fontaine-Ratschow).
Research will also be conducted into risk factors, in particular smoking, diabetes mellitus, lipid metabolism disorders and others. This will be followed by a physical examination. It will begin with the inspection, i.e. the assessment of the affected extremity.
Here, skin color (pale in the case of pAVK), temperature (cold in the case of pAVK), tissue loss, black coloration and ulcers are examined. In addition, further signs of a nutritional disorder (trophic disorder) of the extremity are looked for, such as muscle atrophy, disturbed nail growth or hardening (fibrosis). The doctor will then try to palpate the various pulses (palpation), as this will help to narrow down the location of the narrowing.
These are weaker or no longer palpable in the affected area. For the leg, these are 4 important ones: Even with a stethoscope, a flow sound can be heard at the affected area, since the blood has to pass through a constriction with increased pressure. (Listening with the stethoscope: auscultation).
- Groin pulse (A. femoralis)
- Pulse in the hollow of the knee (A. poplitea)
- Pulse on the back of the foot (A. dorsalis pedis)
- Pulse behind the inner ankle (A. tibialis posterior)
As the last procedure without further technical aids, the blood pressure is determined on both arms and legs. If the blood pressure of the arms is higher than that of the legs, this is an indication of a narrowing in the area of the legs. Normally, the pressure is higher in the legs because they are lower and thus additionally push the blood above them downwards.
A further examination to determine objectively to what extent there is an impairment is the walking test. Here, a treadmill is used to determine how long the pain-free walking distance is (important for the subdivision in stage II, see stage classification according to Fontaine-Ratschow). The most important examination method is Doppler sonography, an ultrasound examination.
It is non-invasive (no intervention in the body) and can be performed quickly. It makes it possible to determine the flow velocity of the blood. Above the constriction, this is greatly increased, since the same blood volume must flow through a smaller inner diameter (lumen).
This examination can also be used to detect certain changes behind the affected area. Radiological examinations can be performed to obtain more precise information about the location, length and extent of the constriction. These include, for example, (3D) MRI angiography (a nuclear spin tomography examination), CT angiography (a computer tomography, a special X-ray procedure) or digital subtraction angiography (DSA, also a special X-ray procedure).
MRI is not possible for patients with pacemakers or metallic implants. All these examinations are performed with the help of contrast agents. However, since there is always a certain risk of the vessel becoming completely blocked, these examinations are normally only performed if there are reasons for interventional therapy.
Either in the form of a catheter procedure or an operation (see Therapy pAVK). It is also important to perform further examinations to determine whether the brain-supplying arteries or coronary vessels (coronaries) are involved.
