Angioplasty and Stent Insertion

Authors:  Dr William Clark*
                        Dr James Burnes*

What are the prerequisites for having an angioplasty and stent insertion done?

Angioplasty can be carried out for a variety of clinical indications. The most common is for the treatment of lower limb ischaemia due to arterial narrowing with atheroma. Other vessels, such as the renal, mesenteric and carotid arteries, can be treated with angioplasty. However, the role of maximal medical therapy versus surgery versus angioplasty for these conditions is a complex issue. The decision to carry out angioplasty will involve an evaluation of the patient’s clinical problem, weighing risk of the procedure versus potential benefit based on the evidence, and the patient’s preferences. It is beyond the scope of this information item to provide a detailed discussion of the evidence regarding the role of angioplasty for various conditions compared with alternative medical and surgical therapy.

Other considerations prior to referral for angioplasty include:

• If a female patient is of child-bearing age, then a pregnancy test is strongly recommended, as the radiation dose to the abdomen from abdominal interventional radiological procedures may be significant in terms of the dose to the foetus.
• It is routine to obtain U, E, Cr and eGFR. In patients with renal function impairment (eGFR < 60) the single most effective way to reduce the likelihood or severity of CIN is intravenous normal saline administration before and after the procedure. The exact amount and rate of administration will depend on patient size and comorbidities, such as active/treated cardiac failure.

Preliminary imaging tests, such as ultrasound, CT angiography or diagnostic angiogram, will usually have been carried out to confirm an arterial abnormality.

What are the absolute contraindications for an angioplasty and stent insertion?

There are no absolute contraindications for angioplasty and stent insertion.

What are the relative contraindications for an angioplasty and stent insertion?

Relative contraindications include:

• Kidney dysfunction making the treated artery worse. eGFR less than 60 is indicative of mild renal function impairment and progressive decrement in renal function beyond this correlates with increased likelihood of CIN. There is no absolute value of eGFR below which the procedure will not be carried out, as there will always be consideration of the risks of having and not having the procedure before it is undertaken by the radiologist. This decision-making process is a multidisciplinary one and not straightforward in patients with multiple comorbidities and a potentially life-threatening illness. If the patient has severe kidney dysfunction, but is not on dialysis, then the procedure can often be carried out using carbon dioxide angiography instead of iodinated contrast. This poses no threat to the kidneys.
• If the patient is pregnant, any procedure involving X-radiation is avoided, except in extreme circumstances.
• Allergy to iodinated contrast media – preparation with steroid premedication might be an option for these patients, which requires discussion with the radiologist.
• Severe physical disability that prevents the patient lying flat.
• Bleeding disorder or anticoagulation with warfarin – although if the INR is less than 2.5, then warfarin can usually be continued if necessary.
• Patient weight exceeds weight limit of machine (usually approximately 160 kg).

What are the adverse effects of an angioplasty and stent insertion?

• Bleeding/bruising at the groin puncture site can cause a significant clinical problem in approximately 3% of cases. If in doubt, an ultrasound test can exclude a false (pseudo) aneurysm. If there is a false aneurysm, it is best treated by ultrasound-guided thrombin injection in the radiology department.
• Making the narrowing in the target artery worse in the short-term. The artery may completely occlude in approximately 1% of patients within 7 days of the procedure. This will make the original symptoms worse and require a second intervention to thrombolyse the clot and treat the underlying problem to stop it re-occluding.
• Allergic reaction to intravascular contrast – most reactions are mild, but very rarely can be severe.
• Renal failure – the risk increases with the use of intravascular contrast, especially if the patient has diabetes or chronic kidney dysfunction or other risk factors for renal impairment, such as a single or transplant kidney, myeloma, gout and so on (see Contrast Medium: Using Gadolinium or Iodine in Patients with Kidney Problems for the full list of risk factors), and adequate preventative steps are not taken.
• Myocardial infarct has increased incidence after any intervention, as a result of stress on the body. It is, however, uncommon.

Are there alternative imaging tests, interventions or surgical procedures to an angioplasty and stent insertion?

The alternatives to angioplasty and stent insertion are either medical (drug) therapy or open surgical therapy. These are best discussed with the referring physician and radiologist.

Useful websites about angioplasty and stent insertion:

Society for Interventional Radiology:
www.sirweb.org/patients/angioplasty-stent

Cardiovascular and Interventional Radiological Society of Europe:
www.cirse.org/index.php?pid=1013

*The author has no conflict of interest with this topic.

Page last modified on 29/3/2017.