Arterial hypertension has many causes, which may be innate (the so called ‘essential’ arterial hypertension) as well as acquired causes.
One of the most important acquired factors which can lead to arterial hypertension is renal artery stenosis. The mechanism by which the narrowing of the renal artery lumen determines arterial hypertension is very complex – the decreased renal excretion of water and salt leads to the production by the kidney of certain substances that determine artery constriction.
Occurrence of hypertension at young ages (less than 30 yrs old) or arterial abdominal bruits are suggestive of a renal artery stenosis. Also, we may suspect the presence of renal artery stenosis in the case of therapy-resistant hypertension, recurrent episodes of cardiac decompensation, and hypertension associated with renal insufficiency.
The diagnosis is initially made by Doppler echocardiography of the renal arteries, which not only identifies the narrowing at this level, but also quantifies the hemodynamic consequences of the stenosis. For a more precise diagnosis, other non-invasive exams (contrast computed tomography, magnetic resonance imaging) or minimally-invasive exams (selective angiography of the renal arteries) can be made.
The goal in renal artery stenosis is the restoration of renal blood flow. Currently, most of the patients can be treated percutaneously by a minimally-invasive approach. The technique implies the positioning of a balloon in the renal artery at the level of the stenosed segment, which, after being inflated, compresses the stenosis, thus restoring the blood flow. The procedure can be completed by the placement of a stent, which maintains artery patency for a longer period of time. The procedure allows the improvement of symptoms, improvement of renal function, and a better control of arterial hypertension.
The main indications of renal artery angioplasty, after confirmation of the renal artery stenosis, are renal function deterioration, accelerated or drug-resistant hypertension, and recurrent episodes of cardiac decompensation consequent to high blood pressure values.
addΠριν τη θεραπεία - Προετοιμασία
Before the procedure, the interventional radiologist will thoroughly explain the intervention to the patient and will answer any question about it. The doctor must be informed about any current medication taken by the patient as well as any previous allergic reactions. Blood tests will be taken before the procedure to assess the coagulation, renal function, hemoglobin level, and other specific tests. If the patient is under anticoagulant therapy, this will be stopped before the procedure. The patient is admitted the day before the planned procedure. He/she should not eat/drink anything the day of the intervention.
addΜετά τη θεραπεία - Χρόνος αποκατάστασης
The catheter will be retired 4-6 hours after the intervention.
Bed rest is needed for 12 hours, and the patient must avoid bending the thigh in order to prevent any possible bleeding or hematoma formation.
Oral hydration is recommended after angioplasty to help eliminate the injected contrast agent.
If a stent is implanted, treatment by clopidogrel (for 1 month) and aspirin (on the long term) will be taken in order to avoid stent restenosis.
After discharge (usually the day after the procedure), you must be followed regularly by your cardiologist.
Follow up: serial Doppler echocardiograms will be carried out in the next months in order to assess the patency of the artery. Sometimes (10-20% of patients) there is a possibility of restenosis, especially in the first 3-6 months after the procedure. It is mandatory to adopt important lifestyle changes (quitting smoking, lowering of cholesterol values, maintaining the blood pressure values within normal limits) in order to avoid such restenosis.
Is it painful?
Pain may occur locally when local anesthesia is made, and while the balloon is inflated, but it will disappear as soon as the balloon is deflated.
How long does it take?
The procedure lasts about an hour. The whole duration depends on the location of the stenosis, as well as the type and complexity of the stenosis (fibromuscular dysplasia – especially in young patients, or atherosclerosis plaque – in the elderly).
Επόμενο: Διαβάστε σχετικά με τους γιατρούς