Introduction
The heart muscle gets its own blood supply through the coronary arteries. When fatty deposits (plaque) narrow or block these arteries, the muscle may not receive enough blood, especially during effort.
In coronary artery bypass grafting, the surgeon takes a healthy blood vessel from another part of the body and joins it to the coronary artery beyond the blockage. Blood can then travel around the narrowed section — a "bypass" — to reach the heart muscle.
Why the procedure is needed
Blocked or narrowed coronary arteries (coronary artery disease) can cause:
- Chest pain or pressure (angina), often brought on by walking, stairs or stress
- Breathlessness, tiredness or reduced ability to do daily activities
- Heart attack, when an artery becomes suddenly blocked
- Weakening of the heart muscle (heart failure) over time
- Rhythm problems linked to poor blood supply to the heart muscle
Who may benefit
- People with blockages in several coronary arteries, particularly when the main left artery is involved
- People with diabetes and multi-vessel disease, where bypass is often considered
- People whose blockages are not suitable for stenting, or who have had stents fail or re-narrow
- People with reduced heart pumping function and blockages that can be bypassed
- Patients for whom the heart team judges bypass the better long-term option after angiography
Graft sources and surgical approaches
The surgeon chooses grafts according to your arteries, age, other illnesses and the quality of the available vessels.
- Chest artery (internal mammary / LIMA)
- An artery from behind the breastbone, usually joined to the main artery at the front of the heart. It is generally the longest-lasting graft.
- Leg vein (saphenous vein)
- A vein from the leg that is widely used for additional bypasses. It is generally less durable over the very long term than an artery graft.
- Arm artery (radial artery)
- An artery from the forearm that may be used in selected patients as another arterial graft.
- On-pump approach
- The heart is temporarily stopped and a heart-lung machine takes over circulation, giving the surgeon a still, bloodless field.
- Off-pump approach
- The bypasses are done on the beating heart without the heart-lung machine. See the separate Off-Pump CABG page.
Procedure overview
Step 1: Before surgery
Your team reviews your angiography, echo, blood tests and medicines. You are told when to stop certain medicines and when to stop eating and drinking.
Step 2: Anaesthesia
The operation is done under general anaesthesia, so you are asleep and feel no pain. Monitoring lines are placed to watch your heart and blood pressure.
Step 3: Surgical access
Most commonly the surgeon opens the breastbone (sternotomy) to reach the heart. The vessels for grafting are collected from the chest, leg or arm.
Step 4: Creating the bypasses
Each graft is stitched beyond a blocked area of the coronary artery. The number of grafts depends on the number and location of the blockages.
Step 5: Closing and monitoring
The breastbone is closed with wires and the skin with stitches. You are taken to the intensive care unit, where breathing, heart rhythm, blood pressure and drainage are closely monitored.
Step 6: Recovery and rehabilitation
Hospital stay is often around a week, followed by several weeks of recovery. Walking is started early, and a cardiac rehabilitation programme, medicines and lifestyle changes help protect the grafts.
Clinical advantages
- May relieve chest pain and improve the ability to be active
- May improve blood flow to heart muscle that was short of supply
- Can offer durable results, particularly with artery grafts, in suitable patients
- In selected patients (for example, multi-vessel disease or diabetes) may offer long-term advantages over stenting
- May lower the chance of future heart-related problems when combined with medicines and healthy habits
Risks and considerations
Every operation carries risk. The points below are general; your own risk depends on your health and on the operation you need.
- Bleeding, infection (including at the chest or leg wound) and slow wound healing
- Irregular heartbeat, most often atrial fibrillation, in the first days after surgery
- Heart attack, stroke or kidney problems — uncommon, but more likely in older patients or those with other illnesses
- Temporary memory or concentration problems after surgery in some patients
- Grafts can narrow again over time; medicines and lifestyle changes remain important
- Risk depends on your age, heart function, diabetes, kidney and lung health, and whether the surgery is urgent
Frequently asked questions
How long do bypass grafts last?
It varies. Artery grafts generally last longer than vein grafts, and many grafts stay open for years. How long they last also depends on blood pressure, cholesterol, diabetes control, smoking and taking medicines regularly.
How long will I be in hospital, and when can I return to normal life?
Many patients stay about five to seven days. Full recovery commonly takes around six to twelve weeks, but your surgeon will give you advice based on your progress.
Is bypass better than stents?
Neither is better for everyone. For some patients (for example, several blocked arteries or diabetes), bypass is often preferred; for others, stenting is appropriate. Your heart team decides after reviewing your angiography.
Will I need medicines after surgery?
Yes, in most cases. Medicines such as aspirin, cholesterol-lowering tablets and blood pressure medicines are usually continued long term to protect the grafts.
Can the blockages come back?
The disease behind the blockages can continue. Stopping smoking, healthy eating, exercise and regular medicines are important to protect both the grafts and the other arteries.
What care is needed after I go home?
Keep the wounds clean and dry, follow your walking plan, avoid heavy lifting as advised, take medicines as prescribed and attend follow-up visits. Seek help urgently for chest pain, fever, wound discharge or breathlessness.
Patient-friendly summary
Bypass surgery creates new routes for blood to reach the heart muscle around blocked arteries. It can relieve symptoms and help in suitable patients, but it is major surgery with real risks and a recovery period. Only a cardiologist or cardiothoracic surgeon can tell whether it is right for you — and medicines, healthy habits and regular follow-up remain important afterwards.