Aortic Valve Diseases and Surgery

Problems occurring in the aortic valve are generally classified as Aortic Stenosis or Aortic Valve Insufficiency, which are the main types of aortic valve diseases. Aortic stenosis restricts the passage of blood, while insufficiency allows blood to leak backward towards the heart.

The aortic valve typically consists of three leaflets in a healthy heart. However, in some cases, the aortic valve can be congenitally bicuspid, meaning it has two leaflets instead of three. Bicuspid Aortic Valve is the most common congenital heart disease but often remains asymptomatic in the early stages. As aortic valve diseases progress (aortic stenosis, aortic insufficiency), complications such as aortic aneurysm (aortic enlargement), aortic dissection (aortic tear), and infective endocarditis can develop.

Symptoms of aortic valve disease may include chest pain, chest tightness, dizziness, fainting after exertion, imbalance, weakness, shortness of breath, and palpitations. These symptoms should be considered as warning signs of aortic valve disease.

How is the Diagnosis of Aortic Valve Diseases Made?

During the examination of the patient based on their complaints, if the doctor hears a heart murmur and after preliminary tests, a definitive diagnosis is made through echocardiography, and if necessary, cardiac catheterization and angiography.

What are the Treatment Methods for Aortic Valve Diseases?

As with all valve diseases, treatment is either Replacement or Reconstruction.

Aortic stenosis occurs when the aortic valve becomes calcified, deformed, and significantly narrowed, making it difficult to open. This condition forces the heart to pump blood through a severely narrowed valve, causing significant strain and pressure on the heart. Over time, this can lead to thickening of the heart muscle and, at an advanced stage, result in heart failure. Aortic stenosis is often related to aging, with the accumulation of calcium deposits on the valve. Other contributing factors include a history of rheumatic fever, radiotherapy, and the development of high cholesterol.

Medication cannot reverse the calcified narrowing of the aortic valve over the years. However, additional drug treatments are provided for heart failure, arrhythmia, and prevention of clot formation, which may occur secondary to aortic valve disease. The treatment for aortic stenosis is surgical or catheter-based.

Aortic Valve Replacement is currently performed using three different methods:

• Open-Heart Surgery, Large Incision (Sternotomy)
• Minimally Invasive Aortic Valve Replacement or Repair Through a Small Incision in the Chest or Armpit (Applying a 3 or 4 cm skin incision)
• Transcatheter Aortic Valve Implantation (TAVI) Method

1. Method: Classic open-heart surgery
2. Method: Minimally invasive surgery through a small incision in the chest (3-4 cm) has become a common method in daily surgical practice. Due to the small incision, it is preferred by patients; however, the final decision always depends on the indication set by the doctor. In this method, the aortic valve is completely removed, and a metal or biological valve is placed in its position. The surgery duration is relatively short, approximately 1.5-2 hours. In this procedure, the old calcified valve is removed, and all calcium deposits are cleaned. A new valve is sewn and placed in its position. Therefore, the use of a Heart-Lung Machine is required. In the closed method, depending on the location where it is performed, only 3-4 cm of the bone is cut.
3. Method: The TAVI Method is a relatively recent development. In this method, the chest is not opened at all, and the aortic valve is replaced with a biological valve by entering through the groin. Additionally, in the TAVI method, a biological aortic valve placed inside a stent is installed in patients. The original faulty aortic valve in TAVI is not removed, as in surgical methods; instead, it is compressed and left in place. The most significant advantage of this method is its completely closed nature and the absence of the need for a Heart-Lung Machine. However, this method has significant disadvantages. Only a biological aortic valve can be installed in the TAVI method. After a long period, the biological valve may deteriorate (denaturation), requiring replacement. While the TAVI method is applied, some complications may occur. For example, in cases of “valve displacement” or failure to fit perfectly, urgent or planned open-heart surgery may be necessary. Even if the valve fits perfectly, a condition known as “paravalvular leak,” where blood leaks from the edge of the valve, may occur. In this case, patients may undergo open-heart surgery in the future. During the TAVI method, the new valve is placed into the heart through a catheter extending from the groin. Therefore, the groin veins and abdominal veins must be of an appropriate size and free from calcification; otherwise, the tearing of these veins may occur, requiring emergency repair by opening the abdomen. During the TAVI procedure, a Heart Angiogram control is applied. Even in the most elite centers, the TAVI procedure shows a mortality rate of approximately 10% (2). In our clinic, we use the quite expensive TAVI method only in very high-risk patients, meaning elderly individuals with additional illnesses, who are not suitable for open or closed surgery.

Patients about to undergo aortic valve surgery should carefully evaluate all these mentioned methods and make decisions accordingly. The experience of the individual performing the procedure and their team is crucial in all three methods. The infrastructure of the hospital, the presence of the surgical team in the TAVI method, and the experience of this team play a significant role in the outcome of the procedure. Despite the advantages and disadvantages of each method, aortic valve stenosis or leakage is a serious condition that must be treated. Otherwise, patients may be exposed to consequences such as heart failure, embolism, and death.

In cases where the aortic valve significantly leaks blood backward or in cases of severe stenosis, where calcification impairs valve function or when both occur simultaneously, serious disruptions in heart rhythm and the risk of embolism can occur, posing a danger to the patient’s life. In such cases, urgent evaluation is necessary, and surgery is indicated.

Postoperative hospitalization lasts for 5 days, and the patient can start going for walks outside within 10 days. When a metal valve is installed, there is no need for another valve replacement throughout the patient’s life. If a biological valve is preferred by the patient, it may be necessary to replace the valve again after 10-15 years, requiring a more challenging surgery. Therefore, metal valves are more often preferred by patients. Patient preference cannot override the indication set by the doctor, and the choice of which valve to install depends on the patient’s medical condition. The most significant disadvantage of a metal valve is that patients need to take Warfarin (Coumadin, Marcumar, etc.), a blood-thinning medication, for their entire life. For the optimal adjustment of this blood-thinning medication, an INR test (determining how much the blood is thinned) is required every month. Due to this, patients need to go to the hospital every month or frequently, have an INR test, and visit the doctor for the adjustment of the medication dosage. In today’s technology, home devices have been developed for this purpose. With these devices, the INR test can now be performed at home with just a drop of blood, and even real-time communication with the doctor can be established through a mobile application for adjusting the medication dosage (see Remote Patient Monitoring Systems).

Sources:

1) Neurologic Complications of Unprotected Transcatheter Aortic Valve Implantation (from the Neuro-TAVI Trial). Am J Cardiol. 2016 Nov 15;118(10):1519-1526 Am J Cardiol. 2016 Nov 15;118(10):1519-1526

2) Incidence and treatment of procedural cardiovascular complications associated with trans-arterial and trans-apical interventional aortic valve implantation in 412 consecutive patients. Eur J Cardiothorac Surg. 2011 Nov;40(5):1105-13. doi: 10.1016/j.ejcts.2011.03.022. Epub 2011 Apr 22.