A healthy Aortic Valve opens and closes over 100,000 times each day and survives for over 3.4 billion heart beats in a person’s lifetime. It is the gateway for blood from the heart to the rest of the body. Aortic Stenosis (AS) is the abnormal narrowing of the aortic valve by calcification, which reduces this blood flow and can result in angina, weakness, and death. AS is congenital or acquired, and the most common valvular abnormality in developed countries. AS afflicts an estimated 2% of people above age 65, 3% above age 75, and 4% above age 85. More than 300,000 people worldwide have been diagnosed with Severe AS. Left untreated, the survival rate at one year is approximately 50%.
For over 40 years, the standard therapy for most AS patients has been Surgical Aortic Valve Replacement (SAVR). SAVR is a type of open-heart surgery in which the diseased leaflets are removed and a replacement surgical valve is sutured in place. However, because this procedure is so invasive, approximately 100,000 patients are ineligible for it due to comorbidities, and nearly another 100,000 patients avoid it due to the risks of surgery.
Transcatheter Aortic Valve Implantation (TAVI) is a new and emerging medical procedure for treating AS. It does not require open-heart surgery and instead uses minimally invasive surgical or percutaneous methods. In TAVI, a bioprosthetic heart valve (called a transcatheter aortic valve, or TAV) is inserted into a specifically designed catheter system. The catheter is then inserted into the femoral artery and advanced under X-Ray-Fluoroscopy towards the heart until the TAV reaches the aortic valve position. The TAV is then deployed inside the diseased valve and starts functioning immediately; the diseased valve is not removed. If the patient’s femoral artery is badly diseased, the catheter can be inserted via the subclavian artery, directly into the aorta, or directly into the apex of the heart. TAVI avoids opening the chest and heart, and is significantly less traumatic than open-heart surgery.
TAVI is a new treatment option for “SAVR-ineligible” patients and those considered “high-risk,” and increasingly “medium-risk,” for SAVR. In fact, the procedure has become the standard of care for SAVR-ineligible patients and was recently approved for medium-risk patients. Over 300,000 TAVI procedures have been conducted since the first TAV was approved in Europe in 2007. The U.S. approved its first TAV in November 2011 for SAVR-ineligible patients, and expanded this approval in October 2012 to high-risk patients. The first FDA approvals for “medium-risk” patients occurred in mid-2016.
The market for TAVs continues to grow. Current TAVI clinical trials include low-risk patients. Low-risk patients, which comprise nearly 50% of all Severe AS patients, are typically younger and require a more durable TAV. Additional markets for TAVs include bicuspid patients, for which few TAVs are designed. It is also expected that TAVs will be used in valve-in-valve procedures, whereby a TAV is deployed inside a diseased surgical or transcatheter valve.
Dr. Thubrikar has invented a next-generation TAV – Optimum TAV – distinguished by its design for durability and performance.