Aortic valve replacement (AV-R) is a procedure in which a patient’s failing aortic valve is replaced with an artificial heart valve. The aortic valve can be affected by a range of diseases; the valve can either become leaky (aortic insufficiency) or partially blocked (aortic stenosis). Current aortic valve replacement approaches include open heart surgery via a sternotomy, minimally invasive cardiac surgery (MICS) and transcatheter aortic valve replacement (TAVR).
When is it necessary to replace the aortic valve?
The aortic valve may need to be replaced for 2 reasons:
the valve has become narrowed (aortic stenosis) – the opening of the valve becomes smaller, obstructing the flow of blood out of the heart
the valve is leaky (aortic regurgitation) – the valve allows blood to flow back through into the heart
The problems can get worse over time and in severe cases can lead to life-threatening problems such as heart failure if left untreated.
There are no medicines to treat aortic valve problems, so replacing the valve will be recommended if you’re at risk of serious complications but are otherwise well enough to have surgery.
About the surgery
Aortic valve replacement is the most effective method of treating severe aortic valve disease. It involves removing the diseased valve and replacing it with an artificial valve. There are two types of artificial valves: biological (tissue) valves (commonly made out of pig tissue (porcine) or cow tissue (bovine), and mechanical valves (made out of carbon fibre). Mechanical valves are very durable, and rarely fail. However they require life long blood thinners (anticoagulation) such as warfarin, which increase the risk of bleeding and need regular monitoring. On the other hand, biological valves do not require blood thinners, but do not last as long as mechanical valves. The average time a biological valve lasts is around 15-20 years, and the patient may require another operation after this. This is a complex decision that ultimately the patient must make, and they should discuss the differences with their surgeon.
In the procedure, the sternum (breast) bone is divided to access the heart. The patient is then put on the heart-lung machine, the heart stopped, and then the aortic valve is replaced. At this time the surgeon may also perform other procedures if needed, such as coronary artery bypass grafting, to avoid the patient needing another operation.
For a while after the surgery, patients may feel worse than they did before surgery. This is normal and is usually related to the trauma of surgery, not necessarily to the functioning of the heart. Patients usually stay in the intensive care unit for 1 – 2 days for monitoring, and then in the nursing unit for 4 – 5 days. Two to three tubes stay in the chest to drain fluid from around the heart, which are usually removed 1 – 3 days after the surgery. Full recovery usually takes about 2 months. Most patients are able to drive in about 3 to 8 weeks after surgery. Your surgeon will provide specific guidelines for your recovery and return to work.
Risks of the surgery
As with all surgery, aortic valve replacement is associated with some risks. Your surgeon will calculate these risks specific to you, and discuss them with you. In the short-term after the operation these include wound infection, bleeding, kidney injury, stroke, heart attack, arrhythmias and pacemaker implantation, and possibly death. In the long-term the artificial valve may fail, and another operation may be required.