Aortic valve stenosis is a narrowing of the heart’s aortic valve, which obstructs blood flow from the heart to the aorta. This condition often develops over many years as calcium deposits build up on the valve leaflets, causing them to become stiff and unable to open fully. Other causes include being born with a bicuspid aortic valve or scarring from rheumatic fever. As the narrowing worsens, the heart must work harder to pump blood, leading to symptoms like chest pain, fatigue, shortness of breath, and dizziness. When symptoms become significant, treatment is necessary. While surgical valve replacement has long been the standard, several effective non-surgical treatments provide alternatives for patients who are not ideal candidates for open-heart surgery.
Transcatheter Aortic Valve Replacement (TAVR): The Leading Non-Surgical Option
Transcatheter aortic valve replacement (TAVR), also known as TAVI, is the primary non-surgical intervention for severe aortic stenosis. The procedure involves implanting a new, collapsible valve within the patient’s narrowed valve. This new valve pushes the old valve’s leaflets aside, taking over the function of regulating blood flow.
The replacement valves are biological, constructed from cow or pig tissue mounted on a metal-mesh frame. There are two main types: balloon-expandable, which are inflated into place with a balloon catheter, and self-expanding, which expand on their own once positioned. The TAVR approach is less invasive than surgical aortic valve replacement (SAVR) because it avoids a large chest incision and the need to stop the heart.
The TAVR Procedure: What to Expect
Before a TAVR procedure, patients undergo imaging tests to measure the aortic valve and assess blood vessels for access. Patients receive either conscious sedation or general anesthesia, as determined by the heart team. The intervention is performed by an interventional cardiologist in a cardiac catheterization lab and takes less than an hour.
The most common delivery method is the transfemoral approach, where a catheter is inserted through a small incision in the femoral artery in the groin. This catheter carries the compressed replacement valve through blood vessels to the heart, where it is positioned and deployed. After confirming the new valve is functioning correctly, the catheter is removed, and patients are monitored before returning home, often within a day or two.
Determining Candidacy for TAVR
A multidisciplinary heart team, including cardiologists and surgeons, determines if a patient is a suitable candidate for TAVR. This team evaluates each patient’s unique circumstances. Initially, TAVR was reserved for individuals at high risk for open-heart surgery, but its use has expanded to include patients at intermediate and even low surgical risk.
Factors in the evaluation include the patient’s age, overall health, frailty, and other medical conditions (comorbidities). Detailed imaging, such as echocardiograms and CT scans, is used to assess the aortic valve’s anatomy and the suitability of blood vessels for catheter access.
Aortic Balloon Valvuloplasty: An Alternative Intervention
Aortic balloon valvuloplasty (ABV) is another non-surgical intervention, but it serves a different purpose than TAVR. In this procedure, a catheter with a balloon tip is guided to the aortic valve and inflated, stretching the opening to improve blood flow. This provides immediate but temporary symptom improvement.
ABV is not a definitive treatment because the valve narrowing (restenosis) often recurs within months. Its primary role is as a “bridge” to a permanent solution like TAVR or surgery by stabilizing ill patients beforehand. For patients who are not candidates for any valve replacement, ABV may be used as a palliative measure for symptom relief.
Medication-Based Management Strategies
For individuals with aortic stenosis, medications do not stop or reverse the valve’s narrowing. Their role is to manage symptoms and reduce strain on the heart, particularly in milder cases or for those awaiting intervention. Lifestyle modifications, like a heart-healthy diet and avoiding strenuous activity, are also recommended.
Physicians may prescribe diuretics to remove excess fluid, which alleviates shortness of breath and swelling. Drugs to control high blood pressure, such as ACE inhibitors, may also be used to ease the heart’s workload. For patients experiencing angina, beta-blockers might be cautiously prescribed.