Aortic Valve Stenosis
Your heart is like an extraordinary machine. From the moment you are conceived, to your very last breath, your heart never stops pumping blood throughout your body. Like any machine, the heart is also subject to wear and tear. In some cases, important components of your heart can become inefficient, requiring repair or replacement.
The aortic valve is one of these parts.
Aortic Valve Stenosis (AVS) is defined as narrowing and hardening of the aortic valve. In most cases, AVS is a slow and gradual process that occurs over years. AVS is generally seen in individuals over the age of 65. However, AVS may develop in children and young adults who are born with abnormal aortic valves. For example, they may have unicuspid or bicuspid valves.
Depending on the severity of your AVS, you may experience signs and symptoms ranging from mild ones (such as shortness of breath) to life-threatening ones (fainting, heart failure).
Your cardiologist would be able to best advise whether you are in need for treatment which may involve medication or aortic valve replacement.
The aortic valve is the gatekeeper between your left ventricle and aorta. By opening and closing, it serves to manage blood flow towards your aorta. It prevents leakage and backflow. Normal aortic valves are tricuspid (they have three flaps or leaflets). Click here for more on the aortic valve and heart structure.
What does this mean for me?
Having AVS does not necessarily mean you will perceive the symptoms associated with the condition. However, the condition may worsen overtime, leading to complications that may affect your well-being.
A normal adult aortic valve has the area of approximately 4 cm². Mild to moderate stenosis is defined by valve area that is between 4 cm² and 1.5 cm². Severe stenosis occurs when the valve area falls below 1 cm². Due to narrowing or leakage, an abnormal aortic valve will force your heart to work harder to pump blood through your aorta and to your body. Like other muscles in your body, if your heart is forced to push or move heavy loads, it will grow and thicken.
With progressive worsening of the valve, you will begin to experience more severe symptoms. It is best to seek medical attention from your cardiologist, who monitor your heart function and recommend lifestyle changes or treatment. See the investigation plan or treatment options for more information.
The following is a general guideline and is not intended to replace advice from your doctor.
The signs and symptoms of Aortic Valve Stenosis vary depending on the severity of the condition. In mild cases, warning signs or symptoms may not be produced, making it hard to detect. The narrower the valve, the more severe the symptoms usually are.
In most cases, survival is not affected before the onset of symptoms. However, when symptoms are present, it is likely that the stenosis has reached a severe state and an aortic valve replacement should be considered.
The three cardinal symptoms of Aortic Valve Stenosis are:
Angina - chest pain and discomfort, a feeling of tightness
Syncope - fainting, a temporary loss of consciousness caused by a drop in blood pressure
Congestive Heart Failure - the heart can no longer pump blood properly, lungs fill with fluid and this may be a peripheral leg swelling.
Some other common symptoms are: shortness of breath with exertion, fatigue during times of increased activity, heart palpitations (rapid, fluttering heartbeat).
Causes: Why do I have AVS?
Aortic valve stenosis may be caused by a number of reasons. For example:
Congenital Heart Defect
Some children are born with an aortic valve that has an abnormal number of "cusps" or leaflets. Normal aortic valves have three flaps of tissue, and are called tricuspid valves. Abnormal valves may contain one, two, or four valves, and may not function properly. This may warrant a replacement as these valves wear out more quickly than normal valves.
As you age, minerals deposit on your aortic valve, causing it to harden and narrow. This may cause the valve to stiffen. This is increasingly common in men and women older than 70 years of age.
Rheumatic fever is a bacterial infection that can cause problems with the heart’s valves. Due to the infection, there is swelling in the heart muscle, which permanently damages the valve tissues. As a result, the leaflets of the valve may stick together, causing a narrowing of the aortic valve.
Long Term Health Implications of AVS
If you are aware of AVS before the onset of severe symptoms, treatment is highly recommended. Once severe symptoms start to present, due to worsening of the AVS, risk for survival decreases significantly, if treatment is not introduced.
Due to increased energy exertion by the left ventricle, the walls of the heart will become thicker. The thickened walls take up more space in the heart chamber, resulting in less room for blood in the lower chambers of the heart. Thus, the heart must work even harder to compensate for this shortage. A thickened heart muscle requires more blood supply and may result in an angina (chest pain).
Next Steps: Investigation Plan
Normally, patients will visit physicians after they have had one or more of the symptoms of aortic valve stenosis. It is possible that there are no symptoms because the problem was found because of a murmur. At this point, some diagnostic procedures will be undertaken, so that an informed decision can be made with regards to treatment. These include one or more of: an echocardiogram, a coronary angiogram, a CT scan, and an ultrasound of the arteries.
An echocardiogram is a test that uses sound waves (ultrasound) to evaluate your heart muscle and heart valves.
This x-ray imaging technique is the standard for evaluating coronary artery disease. A doctor inserts a catheter (a thin, hollow tube) into your artery, through your arm or groin. Using the catheter, a special imaging dye is injected into the artery. The images produced are referred to as the angiogram. If the angiogram is of the aorta, it is referred to as an aortogram.
If you have abnormal kidney function, or an allergy to x-ray dye, medications or extra precautions may be required.
It is critically important that a valve with the correct size is placed in the heart. For this purpose, a Gated Cardiac-CT Angiogram will be performed if TAVI is considered. Doctors will be able to measure the site where the valve needs to be placed. They will be able to examine the height of the coronary arteries, the angle of aortic opening, as well as other dimensions.
The Heart Team
At PMCC, we believe that multidisciplinary teams improve patient care. After you meet with a PMCC cardiologist, your case will be discussed by the "Heart Team". The Heart Team is a team of professionals with a high degree of specialization, that has been assembled to deliver the best possible care for our patients. It consists of Cardiologists, Heart Surgeons, Anesthesiologists, Radiologists, echocardiographers, and specialized nurses. During the “Heart Team” conference, all of your clinical data is presented, including results from the diagnostic imaging tests, as well as your history and other conditions.
The Heart Team will aim to come up with a consensus about the most reasonable course of action for your specific case taking into account all of your clinical features.
Learning Centre Tip
At UHN, there is a technique that limits the amount of x-ray dye used in angiograms. However, for those who have poor kidney functioning, and cannot use dye, a transesophageal echocardiogram may be used (although its results may provide limited information)
Watch this Video about the Immediate Steps involved in the Investigation Plan
Based on the investigation, the Heart Team may recommend various different treatment options. If valve replacement is required, one of two treatment routes will be considered.
In the past, the only way to replace your aortic valve was considered to be open heart surgery. This involves opening the chest, temporarily stopping the heart, excising the old valve and suturing a new valve made from metal or animal tissue. While this method effectively replaces the valve, patients usually spend 4-7 days at hospital after surgery and may take 3-4 months to fully recover.
However, almost 35% of patients with aortic stenosis are categorized as inoperable because they may not be able to survive surgery. For them, mortality rates increase to as much as 50% in the subsequent year if they do not receive treatment. This presents a significant healthcare challenge.
Thankfully in patients who are inoperable, TAVI has proven to be incredibly effective. Patients who cannot have surgery have a 20% absolute increase in survival as compared to treatment with medication alone (at 12 months post-procedurally).
Of AVS Patients are Inoperable
Open Heart Surgery
What is the Transcatheter Aortic Valve Implantation / Replacement (TAVI)?
The aortic valve implant will immediately begin to function in place of your diseased valve, once it is in place.
Following administration of local anesthesia in the skin of the leg and some intravenous sedation to keep you comfortable and relaxed, a cardiac catheter is advanced up to your heart with x-ray guidance. The catheter is a thin, flexible tube which is inserted through your leg, and is guided to the location of the valve replacement in the heart. Your doctor guides the catheter and the device by using x-ray.
After opening up the valve and balloon, a catheter with the new valve is carefully positioned and the replacement valve is deployed. The metal frame is expanded, pushing the leaflets of the old valve out of the way and securing the new valve in place. The catheter is then removed. During the procedure, your heart will continue to beat on its own. A heart or lung bypass machine is not needed.
The replacement valve is composed of a metallic stent and tissue, and immediately starts to function. Over time, your tissues will grow over the implant and it will become a part of your heart.
With the evolution of modern medicine, a minimally invasive procedure known as the Transcatheter Aortic Valve Implantation (TAVI) or Transcatheter Aortic Valve Replacement (TAVR) has become a life-saving treatment for patients with severe aortic stenosis that cannot undergo open-heart surgery. Unlike an open-heart surgery, a catheter approach is minimally invasive. Usually, this means that recovery will often be faster and easier than open-heart surgery. The catheter approach usually takes one hour, and you can be discharged within several days.
Transfemoral TAVI: The opening is made in a large artery in your groin (femoral artery). The doctor threads the catheter through the artery and up to your heart.
Transapical TAVI: The incision is made in the left side of your chest between the ribs. The doctor inserts the catheter through the opening and into your heart.
Your cardiologist will provide full written guidelines in terms of activities and medications. It is important to follow these guidelines, and adhere to the prescriptions. A follow-up appointment will be scheduled 2-3 months post-procedure to ensure a safe and smooth recovery. At that visit you will have an echocardiogram to monitor the device that has been placed and the progress your heart has made in returning to normal. Your doctor will decide at this time whether you should return to your own doctor for follow up or whether further follow up is required.
Watch this video to experience TAVI at the Peter Munk Cardiac Centre.
Watch this video to experience TAVI at the Peter Munk Cardiac Centre.
Accepted to the TAVI Program: Wait-Times
Everything you need to know about the TAVI Pre-Admission Appointment
TAVI and differences between TAVI and Open Heart Surgery
Post TAVI: How long before I can go home?
For Family: What you can do during the procedure.
Everything you need to know about the Operating Room
Living with AVS: Frequently Asked Questions
Do I need medication after a valve implant?
You may need to take a blood thinning medication. If you are already on blood thinners, we will make sure the prescribed medications are right for you before you go home. To avoid possible drug interactions, check with your family doctor or pharmacist before taking any new medication.
What activities can I do?
Before the procedure, your physical activity may have been very limited. So at first, activity may make you feel tired and need to rest. As you gain strength and confidence, you can gradually increase your activity.
Walking is important for your recovery. During the first week at home, try walking around your home or taking a short walk outside each day. Then, gradually increase your activity by walking a little longer each day.
Until your follow-up appointment, please take it easy. Do not lift or carry anything heavy such as groceries. Avoid strenuous activities such as gardening, vacuuming and swimming.
Can I bathe or shower?
You may shower when you get home. After the shower, gently pat the insertion site dry with a clean towel. Do not put cream or powder on it. Your doctor will let you know when you may have a bath.
Can I drive?
Do not drive for 14 days after your procedure. If you have any concerns about driving, please talk to us. If you have had a complicated admission, we will let you know when it is safe for you to drive again.
Can I travel?
Before flying or taking a long trip, please talk with your cardiologist or cardiac surgeon.
Should my health care providers know that I have a new heart valve?
Yes, tell all your care providers that you had a TAVI procedure and have an artificial heart valve. This includes:
your family doctor, dentist and any other doctor you see
your physiotherapist, visiting nurses and home care provider
We will give you a card to carry in your wallet. The card has the type of valve you have and when it was implanted. You may also wish to wear medical identification to let health care providers know that you have an artificial heart valve.
When do I need follow-up appointments?
Your cardiologist will provide full written guidelines in terms of activities and medications. It is important to follow these guidelines, and adhere to the prescriptions. We will give you a follow-up appointment with your cardiologist or cardiac surgeon 2 months after your TAVI procedure. You will have an echocardiogram on the same day.
At your follow-up appointment, ask your doctors any questions that you have about your heart health, physical activity, sexual activity, work and travel.
You will have follow-up appointments every year, around the anniversary of your TAVI procedure.
How do I keep my new valve healthy?
To stay healthy and protect your new heart valve, it is important to prevent germs such as bacteria from entering your body. Bacteria can get into your blood if you have an infection or wound in another part of your body.
For example, if you have an infection in your mouth or on your skin, bacteria can easily get into your blood. The bacteria can cause a serious infection that damages your heart tissue and valves.
Will OHIP (public insurance) cover my TAVI?
How urgent is the treatment?
Once you are symptomatic, it is advisable to receive medical treatment as soon as possible.
Who is a candidate for TAVI in Ontario?
Presently, patients who are inoperable or high risk for open-heart surgery are referred to the TAVI program. We expect that in the future, moderate risk patients will also be referred to the TAVI program. Trials are presently underway on low-risk patients.
What are the chances that the valve implantation will fail?
Many of the early TAVI patients were elderly and very ill with co-morbidities. TAVI procedures on moderate risk and younger patients have only recently begun. As such, data on long term outcomes is not available. However, presently there is very little evidence with premature valve failure.
When is TAVI preferable to surgery or vice versa?
In high risk patients, TAVI has proven to be a better option. This is due to the non-invasive nature of the procedure, which poses a reduced risk to the patient, as compared to open-heart surgery. The heart team will carefully assess your situation and advise you as to what the best option there is for you.
In some complicated cases, surgery may be the only option.