Coronary angioplasty and stent insertion is an invasive treatment targeted at restoring normal patency and blood flow in a diseased coronary artery. It was first performed in 1977 by Andreas Gruentzig in Zurich, Switzerland. Approximately, one in three patients having a diagnostic coronary angiography will require coronary angioplasty. The remaining will either continue on medical management or require coronary artery bypass surgery (CABG).
What is coronary angioplasty?
Prior to the procedure, you will be given a local anaesthetic. A small tube with a small inflatable balloon at its tip is then advanced through to one of your coronary arteries either via the groin or arm. Your cardiologist will then select the target artery using X ray guidance and gently inflate the balloon so that it compresses and collapses the adjacent plaque. This usually restores the patency of the blood vessel and allows blood to flow to the distal heart muscle; a procedure called as balloon angioplasty (Figure 1). In addition, a ring of metal meshwork which is called a stent may envelope the balloon. Therefore, when the balloon is inflated, the stent concomitantly expands. Once the stent attains a stable position, the balloon is deflated and retrieved leaving the stent in place (balloon angioplasty and stent insertion, Figure 1).
Dr Omar Rana is a UK-trained consultant interventional cardiologist who practices at Omar Hospital & Cardiac Centre and performs coronary angioplasty and stent insertion.
Are there any complications?
A small number of patients may get complications. Occasionally, the treatment (angioplasty and stent insertion) may completely block off or tear an artery. If this happens then your cardiologist may recommend an urgent CABG. Therefore, it is important that you are prepared and counseled for this eventuality although, this does not happen in more than 5 in 1000 cases in experienced hands.
Will the stent last for a life-time?
Not infrequently the stent placed in an artery may get blocked. This phenomenon is termed as in-stent restenosis (ISR ). Up to 30% stents can get blocked within 6 months of deployment. There are several factors which can influence this outcome. These include the size of the artery, the medical history of the patient (for example diabetes mellitus), any resistance to platelet inhibiting therapy (see below). Platelets are blood cells which allow clot formation. Following stent deployment certain blood thinners (antiplatelet agents) are administered to minimize this and hence allow the stents to remain patent. Certain individuals may be genetically resistant to the actions of these drugs and are thereby at an increased risk of ISR.
What happens afterwards?
Following the procedure you will be checked by a member of the team looking after you before allowing you home. This will include satisfactory inspection of the puncture site from where the catheter was introduced. If there is a significant bruise or swelling then you will be asked to stay for 24-48 hours for observation. Prior to discharge, please make sure that you understand the reason and dosages of your medications.
For the first few days you may experience some tenderness or bruising around the puncture site. If this persists then contact your doctor. Furthermore, it is important to avoid heavy weight lifting for at least a week following coronary angioplasty. In addition, you should not drive a car for a week. If you drive a heavy goods vehicle then you should not drive for six weeks following this procedure and your doctor may arrange you to have an exercise treadmill test prior to recommencement of your driving.
Figure 1. Coronary angioplasty with balloon inflation alone (left side of the figure) and subsequent stent deployment (right side of the figure).