Coronary artery bypass grafting
- What is Coronary Artery Bypass Grafting?
- Indications for CABG
- Types of Coronary Artery Bypass Grafting
- Procedure of Coronary Artery Bypass Grafting
- Rehabilitation and recommendations for patient
- Risks and contraindications to CABG
What is Coronary Artery Bypass Grafting?
Coronary Artery Bypass Grafting (CABG) is a surgical method to recover a blood flow in the coronary arteries which have been narrowed due to some cardiac disease, for example, ischaemic heart disease (IHD). “Grafts” act as anastomoses which create a bypass on cardiac vessels and increase a blood flow.
During the operation a surgeon sews up the original vessel of the patient to the coronary artery near the area of narrowing. Thus the surgeon allows the blood flow to “bypass” the blocked area of artery. After installations of the grafts the amount of the blood supplied to the heart increases and angina attacks disappear.
Indications for CABG
Prognostic conditions of the patient for performing the CABG:
- over 50% obstruction of the left coronary artery;
- 70% narrowing of cardiac vessels;
- stenosis of the anterior interventricular branch.
Cardiologists distinguish 3 groups of indications for the CABG:
- The first group consists of the patients with angina, IHD, which do not show improvement after receipt of medication and the patients with the ischemic pulmonary oedema;
- The second group includes the patients with severe angina whose long-term prognosis will be greatly improved by the surgery which will prevent myocardial ischemia; the patients with over 50% stenosis of the left coronary artery;
- The third group represents the cases when the patient need the CABG as additional support before the planned heart surgery.
Types of Coronary Artery Bypass Grafting
According to its functionality the coronary artery bypass grafting can be divided into:
- On-Pump CABG with cardioplegia;
- Off-Pump CABG on a beating heart.
There are several types of vascular grafts (bypasses). Application of the particular type of graft depends on location of the blocked area in the coronary artery, volume of the damaged area and diameter of the artery:
Internal thoracic artery is the most oftenly used graft because it has the best long-period results. As a rule, a surgeon takes the unchanged artery from its area and sews its end in the coronary artery bypassing the damaged segment. If the thoracic artery is taken from the organism in full it becomes a so called “free graft”.
Radial artery is located in the hand together with the ulnar artery. Considering that the ulnar artery is a dominant blood supplier of the hand, intake of the radial artery during operation does not pose a threat for the organism. Prior to the procedure a doctor makes tests to determine if the radial artery can be used.
Great saphenous vein is often used as a graft. To take the vein a surgeon makes an incision or several small incisions along its location. The technique to be used for the vein intake is determined by the attending doctor in each case individually.
Procedure of Coronary Artery Bypass Grafting
What is necessary to know about the preparation to and the procedure of the CABG surgery?
Usually the patient is hospitalized 3-5 days prior to the surgery. In the inpatient department (s)he undergoes the necessary examinations and prepares to the surgery - (s)he acquires methods of regular breathing and coughing up which can be useful during rehabilitation.
During the surgery, a special device “heart-lungs” carries out functions of heart and lungs. Thus a surgeon can make a bypass grafting of all necessary arteries. When finishing the CABG a doctor installs drain tubes in the chest to remove the liquid from the operated area. Then the wound is stitched and the patient is delivered to the intensive care unit where he stays until the complete stabilization of his/her condition.
Rehabilitation and recommendations for patient
During the first days after the coronary artery bypass grafting the patient must strictly follow these recommendations:
- to control the amount of consumed and excreted water, making notes for the attending doctor;
- to make respiratory exercises to stabilize breath and prevent pneumonia development. Respiratory gymnastics includes air toys, massage above the lungs area with tapping;
- at the early stage of rehabilitation it is extremely important to cough up because some patient can aggravate the situation by cough;
- chest corset should be worn for the quickest healing of the wound.
The patient can return to the sedentary work in 1.5 months after discharge from the hospital. Heavier physical work can require longer period of recovery, some patient will not be able to return to the previous work because of the contraindications.
In general, patients after the CABG have their usual lifestyle. Walking and stair climbing are particularly useful during rehabilitation period. But they should avoid longtime walks at very cold or too hot weather which exhaust the organism. In such a case it is better to create the conditions for physical activity at home, indoors.
Certainly, bad habits should be quitted — smoking can provoke heart attack. The patient should constantly monitor his blood pressure. (S)he should revise the diet and reduce consumption of salt, fats and products rich in cholesterol. Weight control is also recommended.
The patient is allowed to start driving when his/her physical condition is normalized. If driving belongs to your professional duties, you should discuss with the doctor the period of your returning to work.
The chest will completely recover in 3 months after the surgery. During this time no loads on the chest area are recommended and thus the patient should mind this factor during sexual life. As for the rest, there are no contraindications.
Risks and contraindications to CABG
The coronary artery bypass grafting eliminates a pain syndrome and abnormalities of coronary arteries but does not relieve in full from the atherosclerosis. The main aim of the procedure is to improve the patient’s condition for long term and to minimize the effect of atherosclerosis on the vessels.
Cardiologists advise the CABG because of inconvenience and low long-period efficiency rate of the prolonged medication.
In terms of mortality the coronary artery bypass grafting has extremely low risks - 3-2 %. The mortality rate after such operation is 3 times lower in comparison with the antianginal therapy and 2 times lower than after a longtime anti-ischemic therapy.
Contraindications to the surgery:
- damage of all coronary arteries;
- congestive cardiac and renal failure;
- chronic nonspecific pulmonary pathologies;
- renal failure;
There are some risk factors in elderly patients but the age is not an absolute contraindication to the CABG. This is why prior to planning the surgery the doctor prescribes comprehensive examination of the patient and then decides if the patient can undergo the CABG.