Transcatheter aortic valve implantation, often referred to as TAVI, is a minimally invasive medical procedure to replace a diseased heart valve. It offers an alternative to traditional open-heart surgery for individuals with a narrowed aortic valve. The procedure involves inserting a new valve without removing the old one, improving blood flow from the heart. The new valve is delivered through a flexible tube, a catheter, inserted into a blood vessel.
The Condition Treated by TAVI
TAVI addresses severe aortic stenosis, a condition where the aortic valve opening narrows. This valve is between the heart’s left ventricle and the aorta. When the valve narrows, the left ventricle must exert more force to pump oxygen-rich blood through the constricted opening. This increased workload can cause the heart muscle to thicken and, over time, may weaken the heart.
The most common cause of aortic stenosis is calcium deposits on the valve leaflets, often associated with aging. Other causes include congenital heart defects or damage from infections.
Symptoms typically manifest when the narrowing becomes significant, worsening with physical activity. Common symptoms include chest pain or tightness, shortness of breath, and fatigue, particularly during exertion. Individuals may also experience lightheadedness, dizziness, or fainting spells.
Determining Candidacy for the Procedure
The decision to proceed with TAVI involves a comprehensive evaluation by a specialized multidisciplinary “Heart Team.” This team typically includes interventional cardiologists, cardiac surgeons, cardiac imaging specialists, and cardiac anesthetists.
The evaluation process involves diagnostic tests to assess the severity of aortic stenosis and the patient’s overall health. These tests often include an echocardiogram, a CT scan of the aorta and surrounding vessels, a coronary angiogram, chest X-ray, and various blood tests.
Historically, TAVI was primarily for patients at high or prohibitive risk for traditional open-heart surgical aortic valve replacement (SAVR). Factors contributing to this risk include advanced age and multiple underlying health conditions. Recent advancements have led to TAVI’s expanding use for patients at intermediate and lower surgical risk.
The Heart Team considers a patient’s anatomical suitability, such as the size and shape of the aortic valve annulus and the condition of the blood vessels for catheter insertion. The team weighs potential benefits against risks or other medical conditions.
The TAVI Procedure Explained
The TAVI procedure typically takes one to two hours. Patients often receive conscious sedation, though general anesthesia may be used. The procedure is performed in a specialized cardiac catheterization lab.
The most common access method involves inserting a catheter into the femoral artery in the groin. If the femoral artery is not suitable, alternative access points may be used, such as the subclavian artery or a small incision directly into the heart’s apex.
Once inserted, the catheter is advanced through blood vessels, under continuous X-ray imaging, until it reaches the diseased aortic valve. The new, collapsible artificial valve is then delivered through the catheter. The valve is precisely positioned within the opening of the existing, narrowed aortic valve.
The new valve is then expanded, anchoring itself in place. Immediately upon deployment, the new valve begins to regulate blood flow.
Recovery and Life After Implantation
Following TAVI, patients are closely monitored in a recovery area. Most patients begin walking within a day or two.
The typical hospital stay after TAVI is one to two days. Upon discharge, patients receive instructions on wound care for the catheter insertion site. Light activities are encouraged, while strenuous exertion and heavy lifting should be avoided for a few weeks.
TAVI often leads to significant improvement in symptoms like chest pain and shortness of breath, enhancing quality of life. Long-term management involves prescribed medications, including blood thinners, to prevent blood clots. Regular follow-up appointments with a cardiologist are scheduled to monitor valve function and overall heart health.
During these visits, the medical team assesses for potential issues, such as valve leakage or the need for a pacemaker, which can occur. Patients are advised on a heart-healthy diet and gradual resumption of physical activity.