Why do Grafts Fail So Soon? Understanding Long-Term Patency Trends
Medicine Made Simple:
CABG surgery works by creating new routes for blood to flow to the heart using grafts from the patient’s body. But sometimes these grafts can narrow or fail sooner than expected. This blog explains what graft patency means, why some grafts last longer than others, common reasons for failure, and how patients can improve long-term outcomes. Written in simple language, it helps patients and families understand what to expect after CABG and how to care for their heart health.
What Does Patency Mean?
Patency is a medical term that means how open and functional a graft or artery remains after surgery. A patent graft means blood is flowing smoothly through it, providing the heart muscle with the oxygen it needs. When a graft loses patency, it means it has narrowed or blocked, reducing blood flow to the heart. This can cause symptoms to come back, such as chest pain or shortness of breath, and in some cases it may even lead to a heart attack. Patency is therefore an important measure of how successful bypass surgery is in the long run.
Types of Grafts Used in CABG
Surgeons usually use two main types of grafts:
- Artery grafts: These come from arteries such as the internal mammary artery (IMA) from the chest or the radial artery from the arm. Arteries are stronger, designed to handle high pressure, and tend to stay open longer. Studies show that IMA grafts are the most reliable and have the best long-term patency rates.
- Vein grafts: These are usually taken from the saphenous vein in the leg. Veins are easier to harvest and allow surgeons to bypass multiple blockages. However, veins are not naturally exposed to the same blood pressure as arteries, so they are more prone to narrowing or failing over time.
How Long Do Grafts Last?
The lifespan of a graft depends on the type of blood vessel used, the patient’s health, and lifestyle choices after surgery. On average, arterial grafts like the internal mammary artery remain open in more than 90% of patients even 10 years after surgery. Radial artery grafts also perform well, with about 80% still open at 10 years.
Vein grafts, however, show a different story. Studies indicate that about 15–20% of vein grafts may close within the first year. At 10 years, nearly half of vein grafts may fail. This does not mean all patients will have problems, but it does explain why doctors emphasize lifestyle changes and medicines after surgery.
Why Do Some Grafts Fail Early?
While most grafts work well after surgery, some may fail earlier than expected. This can happen in the first few weeks or months due to blood clots forming inside the graft, which block blood flow. Technical issues during surgery, such as how the graft is attached, may also affect outcomes. In addition, patients with very small or heavily diseased blood vessels may be at greater risk of early graft failure. Thankfully, early failure is uncommon, and modern surgical techniques have reduced this risk significantly.
Why Do Grafts Narrow Over Time?
Over the years, grafts may narrow or close due to the same process that caused the original heart disease—atherosclerosis. This is when fatty deposits build up inside the vessel walls. Risk factors like high cholesterol, smoking, diabetes, obesity, and high blood pressure accelerate this process. Vein grafts are especially vulnerable because they are not naturally built to handle high pressure and can develop thickened walls more quickly.
In contrast, artery grafts are naturally suited to high-pressure blood flow and therefore last much longer.
What Symptoms Suggest Graft Failure?
If grafts begin to fail, patients may notice symptoms that are very similar to those they experienced before surgery. These include chest pain or discomfort (angina), breathlessness, fatigue, or reduced ability to exercise. Sometimes symptoms are mild, but in other cases they can be sudden and severe. It is important to recognize these warning signs early and consult a doctor. Doctors may recommend non-invasive tests such as stress tests or CT angiography, and if needed, invasive angiography to check the grafts directly.
Can Failed Grafts Be Treated?
Yes, treatment is possible if a graft fails. The choice depends on how severe the blockage is and the patient’s overall condition. Medicines such as blood thinners, cholesterol-lowering drugs, and anti-anginal medicines can help manage mild narrowing. If the graft is significantly blocked, angioplasty and stenting can often be used to open it. In rare and complex cases, another bypass surgery may be required, although this is more complicated than the first operation. Thankfully, repeat surgery is not common, and most cases are managed with medicines or stents.
How Patients Can Protect Their Grafts
Patients play a crucial role in protecting their grafts and ensuring long-term success of CABG. Doctors strongly recommend a combination of lifestyle changes and regular medicines. This includes:
- Taking prescribed medicines such as aspirin, statins, and blood pressure drugs without fail.
- Following a balanced diet rich in fruits, vegetables, lean proteins, and whole grains while limiting unhealthy fats and sugars.
- Exercising regularly, starting with supervised cardiac rehabilitation and then continuing with daily physical activity.
- Quitting smoking completely, as it is one of the biggest causes of graft failure.
- Attending regular check-ups with a cardiologist to monitor graft function and overall heart health.
What the Latest Research Shows
Medical research has shown clear differences in how long grafts last. The internal mammary artery is considered the gold standard because it has the best long-term patency. Surgeons now often try to use more than one arterial graft when possible to improve survival and reduce future procedures.
Studies also highlight the importance of aggressive risk factor management—controlling blood pressure, cholesterol, and diabetes can significantly extend graft life. Newer medicines, such as stronger cholesterol-lowering drugs, are also improving outcomes for patients after CABG.
Patient Experiences
Patients often share mixed experiences about graft outcomes. Some are relieved to know their artery grafts are still functioning well even after many years. Others feel discouraged if vein grafts fail earlier than expected. However, many also find reassurance in the fact that modern treatments like stents and advanced medicines can help manage failed grafts effectively.
Hearing real-life stories can be comforting for new patients, as they show that even when challenges arise, there are always solutions available.
If you or your loved one has undergone CABG surgery, protecting your grafts should be a top priority. Following your doctor’s advice, taking medicines regularly, and adopting a healthy lifestyle can make a huge difference. If you experience symptoms like chest pain or breathlessness, do not ignore them—early action can prevent complications. Our hospital offers comprehensive cardiac care, including follow-up testing, rehabilitation, and advanced treatments to ensure your grafts last as long as possible. Book a consultation with our heart team today and take control of your recovery journey.
References and Sources
American Heart Association
Cleveland Clinic
National Institutes of Health
Mayo Clinic
*Information contained in this article is not intended or designed to be a substitute for professional medical advice, diagnosis, or treatment. It is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other professional health care provider with any questions you may have regarding a medical condition or advice in relation thereto.
