In some cases, the fatty patches, or 'plaques', (atheroma) re-form within the small tube (stent) over the following few months and years. This may narrow the artery again and angina pains may return. It is difficult to give figures as to how often this occurs. If it does, the procedure can be repeated, or other treatments for angina can be considered, such as coronary artery bypass grafting.
Newer techniques are being developed to try to prevent this possible problem. For example, stents that are coated with chemicals which prevent the local formation of atheroma are being developed. It may be that these coated stents (called 'drug-eluting stents') will be commonly used in the near future.