Blocked coronary arteries require surgical treatment to prevent a heart attack or rapidly restore blood flow to the heart muscle after a heart attack. Depending on the situation, different methods are used, such as balloon dilation, a coronary stent or a bypass operation.
Overview of heart procedures
The coronary arteries surround the heart in a crown-like manner and are responsible for blood flow to the heart. If deposits (arteriosclerosis) cause the coronary arteries to become blocked or narrowed, this results in coronary heart disease (CHD), and if a coronary artery is completely obstructed, a heart attack.
Modern medicine offers various options for expanding, opening or bypassing narrowed or blocked coronary arteries. These interventions are aimed at preventing a heart attack, or if one has already occurred, rapidly restoring blood flow.
The treatment method chosen depends on the number and position of the narrowed arteries, the severity of the narrowing and the long-term chances of success. The options available for treating narrowed coronary arteries are balloon dilation, a coronary stent and heart bypass surgery.
Balloon dilation and coronary stent
Balloon dilation, also known as percutaneous transluminal coronary angioplasty (PTCA), is often performed in combination with a stent. This procedure is used to expand or open up narrowed coronary arteries. The purpose of the stent is to support the arterial walls after expansion and to keep them open permanently. You can find all information about the process of balloon dilation in combination with a stent on the treatment page ‘Balloon dilation’.
Bypass operation (coronary artery bypass surgery)
If it is not possible to open the blocked or narrowed coronary artery using balloon dilation, a bypass operation offers another chance. The aim of this treatment method is to divert blood around narrowed or blocked parts of the coronary arteries to improve blood flow to the heart. This is done by inserting a blood vessel (known as a graft) from another part of the body, usually a vein from the leg or an artery from the chest, to create a detour or bypass around the affected area.
Treatment goal of a bypass operation
A bypass operation on the heart is crucial for preventing complications of coronary heart disease (CHD) such as heart attack, heart failure or arrhythmias. Furthermore, the intervention can help to relieve symptoms such as shortness of breath and chest pain (angina pectoris).
Procedure of a bypass operation
Before a bypass operation, a specialist in cardiology examines the heart and identifies the precise location of any narrowed areas by means of cardiac catheterisation. Additionally, other standard examinations, including an electrocardiogram (ECG), thoracic X-ray, blood pressure measurements and blood tests are performed.
Based on the results of the tests, heart surgeons decide whether to perform the treatment as open-heart surgery or a minimally invasive procedure.
Open-heart bypass operation
An open-heart bypass operation is usually performed under general anaesthesia. The surgical procedure begins with a longitudinal incision on the sternum to open the chest and gain access to the heart.
Chest arteries (internal mammary arteries) are usually used as graft vessels to bypass narrowed coronary arteries. Their size makes them well suited to this, and they can easily be removed as the chest wall is still supplied with blood via other arteries. Part of a leg vein is often also used.
To enable the new blood vessel segment to be attached to the coronary arteries, the heart is immobilised with a cardioplegic solution and the circulation maintained using a heart-lung bypass machine. The other end of the blood vessel is then connected to the aorta directly. This serves to bypass the blocked artery and restore blood circulation. After the cardioplegic solution has been flushed out, the heart starts beating again by itself. The procedure generally takes around three hours.
The OPCAB method (off-pump coronary artery bypass surgery) is sometimes used as an alternative to the heart-lung bypass machine. This involves the use of stabilisers to keep the heart surface above the coronary arteries as still as possible, and the blood vessels can be sewn on while the heart is beating.
Minimally invasive direct coronary artery bypass operation (MIDCAB)
Recently, bypass operations are increasingly being performed as minimally invasive surgical procedures, with the heart only accessed via small incisions, meaning the sternum does not need to be opened.
The benefits of this method include a shorter recovery time, less pain and a reduced risk of complications. Nevertheless, it is not suitable for all patients, especially when multiple arteries are affected. The minimally invasive technique tends to be used if no more than three coronary arteries are blocked.
Preparation and precautions
Patients taking blood-thinning medication should discontinue these in good time after consulting with the attending doctor in order to minimise the risk of bleeding during treatment. Patients are usually admitted to hospital one day before the operation to allow all necessary preparations to be made. On the day of the operation, the patient must have an empty stomach. This means that they should refrain from eating or drinking several hours beforehand to prevent any anaesthesia-related complications.
Recovery and aftercare
After a bypass operation, the patient usually stays in hospital for six to eight days, depending on how their healing is progressing. They usually spend the first one to two days in the intensive care unit to ensure close monitoring. Once their condition is stable, the patient is moved to a normal ward, where the healing phase continues.
They must avoid lifting heavy loads until their wounds have healed completely. After the bypass operation, a rehabilitation programme lasting at least four to six weeks is recommended in order to start appropriate circulation training. During the rehabilitation programme, patients also learn how to keep their heart healthy. It generally takes around twelve weeks to reach full performance again. Regular follow-up checks are performed to examine the function and performance of the heart.
The long-term results of a bypass operation are excellent. In around 90 % of those affected, the bypass grafts remain functional even after 20 years.
Potential complications
A bypass operation is a routine procedure. However, as with all surgical treatment methods, complications and risks can arise in rare cases. These include infections, post-surgical bleeding or the formation of blood clots (thromboses). If complications occur in rare cases, these are usually easy to treat.
