TAVI, or transcatheter aortic valve implantation, is a less invasive way of replacing a diseased aortic valve. Instead of removing the old valve through open-heart surgery, a replacement valve is delivered through a catheter and positioned inside the existing aortic valve.
Although TAVI avoids many aspects of conventional open-heart surgery, it is still a major heart procedure and can cause complications. Most patients undergo TAVI without a major complication, but understanding the possible risks can help patients and families know what doctors are monitoring before, during and after the procedure.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
If you are learning about the procedure itself, our guide to TAVI/TAVR treatment explains how the valve is delivered and implanted.
Why can complications occur after TAVI?
TAVI involves several delicate steps. A catheter and replacement valve must travel through the blood vessels to the heart, cross the narrowed aortic valve and then be positioned accurately within the diseased valve.
The heart's electrical conduction system, coronary arteries, aorta and major blood vessels are all close to the structures involved in the procedure. In addition, many patients undergoing TAVI are older adults who may already have kidney disease, vascular disease or other medical conditions. As a result, complications can arise from the catheter procedure itself, the implanted valve or the patient's underlying health.
The main complications doctors watch for
TAVI complications vary in severity. Some are temporary and can be managed with observation or medication, while others may require an additional procedure or longer hospital monitoring. The main complications include:
- Bleeding and blood-vessel complications
- Stroke
- Heart rhythm and conduction problems
- Paravalvular leakage
- Kidney injury
- Valve positioning or deployment problems
- Heart attack or coronary artery obstruction
- Infection
- Valve thrombosis or later valve dysfunction
1. Bleeding and blood-vessel complications
Because TAVI is usually performed through an artery, most commonly the femoral artery in the groin, the access site can develop complications.
These may include bleeding, bruising, formation of a blood collection under the skin, narrowing or injury of the artery, or problems with blood flow to the leg.
Modern TAVI equipment and improved access techniques have reduced these complications, but vascular assessment remains an important part of pre-procedure planning.
CT imaging can help doctors determine whether the arteries are large and healthy enough to safely accommodate the delivery system.
2. Stroke
Stroke is one of the most serious potential complications of TAVI. During the procedure, manipulation of the catheter and valve within the heart and aorta can dislodge tiny particles of calcium or other material. These particles can travel to the brain and interfere with blood flow.
The risk of clinically apparent stroke is relatively low, but it is taken seriously because even a small stroke can have a significant effect on independence and quality of life. Careful procedural planning and monitoring are used to reduce the risk.
3. Heart rhythm problems and the need for a pacemaker
The aortic valve lies close to the heart's electrical conduction system. When a new valve expands inside the native valve, it can sometimes interfere with these electrical pathways.
This may cause an abnormal heart rhythm or a conduction problem. Some patients develop a heart block that requires a permanent pacemaker.
The likelihood varies according to the type of transcatheter valve, the patient's existing electrical conduction pattern and the anatomy of the aortic valve and surrounding structures.
4. Paravalvular leak
A replacement valve needs to seal properly within the native aortic valve. Sometimes a small amount of blood can leak around the outside of the new valve rather than passing entirely through it. This is called paravalvular leak or paravalvular regurgitation. Small leaks may have little clinical significance, while more substantial leakage can affect heart function and may require further treatment.
5. Kidney injury
Some patients develop a temporary decline in kidney function after TAVI. This is known as acute kidney injury. Several factors can contribute, including the use of contrast material during imaging, changes in blood pressure, underlying kidney disease and the patient's overall condition.
The risk is particularly important in older adults and patients who already have impaired kidney function. Doctors therefore check kidney function before and after TAVI and take steps to minimise unnecessary contrast exposure and other factors that could place additional stress on the kidneys.
6. Valve positioning or deployment problems
The replacement valve must be positioned precisely. If it is implanted too high, too low or in an unsuitable position, it may not function as intended or may affect nearby structures.
Modern TAVI systems are designed to improve positioning and reduce these problems, while detailed CT imaging helps the team plan the ideal implantation position before the procedure. In uncommon situations, additional intervention may be required to correct a valve-related problem.
7. Coronary artery obstruction
The openings of the coronary arteries are located close to the aortic valve. In rare cases, the native valve leaflets or other tissue can interfere with these openings when the new valve is deployed.
This can reduce blood flow to the heart muscle and cause a serious complication. Pre-procedure CT imaging is particularly important for identifying patients who may have a higher risk of coronary obstruction. The position of the coronary arteries, the size of the aortic root and the relationship between these structures are carefully evaluated before selecting the valve and implantation strategy.
8. Heart attack and other cardiac complications
Although uncommon, TAVI can be associated with cardiac complications, including myocardial injury or heart attack. These complications may result from obstruction of a coronary artery, problems with blood flow or other procedural events. Patients are continuously monitored during the procedure, and the team is prepared to respond quickly if a cardiac complication occurs.
9. Infection
As with other invasive medical procedures, infection is a possible complication of TAVI. Infections can involve the vascular access site or, more seriously, the implanted heart valve. Infection involving a prosthetic valve is uncommon but can be serious. Sterile procedural techniques and appropriate peri-procedure care are used to reduce the risk.
10. Blood clots and valve thrombosis
Blood clots can form on or around a prosthetic valve, although clinically significant valve thrombosis is uncommon. Valve thrombosis can interfere with the movement of the valve leaflets and affect valve function.
Doctors may use antithrombotic medication after TAVI according to the patient's individual circumstances and current treatment recommendations. The exact medication plan depends on factors such as whether the patient has another reason to take anticoagulants and the overall balance between clotting and bleeding risks.
Which patients may have a higher risk of complications?
TAVI is not associated with the same level of risk for every patient. Risk can be influenced by:
- Advanced age and frailty
- Kidney disease
- Peripheral vascular disease
- Existing conduction abnormalities
- Heavily calcified aortic valve anatomy
- Bicuspid aortic valve anatomy
- Small or difficult vascular access vessels
- Previous heart procedures
- Other significant heart or medical conditions
This is why doctors do not assess TAVI risk from age or surgical risk score alone. Detailed imaging and a comprehensive clinical assessment are used to identify individual risk factors.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
How do doctors reduce the risk of complications?
Risk reduction begins before the procedure. Detailed imaging helps identify the safest access route, determine the appropriate valve size and assess the relationship between the valve, coronary arteries and surrounding structures.
Careful patient selection helps ensure that TAVI is being offered when the expected benefit outweighs the potential risks. Continuous monitoring during and after the procedure allows complications such as abnormal heart rhythms, bleeding or changes in blood pressure to be identified quickly.
Does having a TAVI complication mean the procedure has failed?
Not necessarily. Some complications are temporary and can be managed without another major procedure. For example, a patient may develop a conduction abnormality that requires monitoring before the need for a permanent pacemaker is determined.
Other complications may require additional treatment. The significance of a complication depends on its severity, how quickly it is recognised and how effectively it can be managed.
The presence of a known procedural risk does not mean that the procedure is expected to have a poor outcome. It means that the medical team plans for these possibilities and monitors the patient accordingly.
The Bottom Line
TAVI has become an established treatment for severe aortic stenosis and can provide an effective alternative to open-heart valve replacement for appropriately selected patients. However, less invasive does not mean risk-free.
The main complications doctors watch for include bleeding and vascular injury, stroke, heart conduction problems, need for a pacemaker, paravalvular leakage, kidney injury, valve-related complications and, more rarely, coronary obstruction or serious infection.
The good news is that modern TAVI planning has become increasingly precise. CT imaging, improved valve technology, careful patient selection and experienced Heart Teams all help reduce and manage these risks.
*AI-generated image - for illustration only. Clinical accuracy is not guaranteed.
For a patient considering TAVI, the most useful question is not simply whether complications are possible. It is how the individual's specific risk factors compare with the expected benefit of treating severe aortic stenosis. That assessment allows the Heart Team to choose the safest and most appropriate treatment strategy for the individual patient.
