TAVI/TAVR – Transcatheter Aortic Valve Implantation/Replacement - Revolution in the field of treating heart valve diseases
What is TAVI/TAVR?
The Transcatheter heart valve replacement (TAVR) procedure offers hope for heart patients with inoperable stenosis (the Heart’s semilunar valve fails to open correctly). A TAVR artificial valve mounted on a catheter is inserted via the Femoral artery (groin area) and placed within the place of an old non-functioning valve, without requiring an open operation.
How is it different from the regular procedures?
When an individual is diagnosed with Aortic stenosis (a Heart Valve disease) and sees the symptoms, it is advisable to undergo the treatment immediately as chances of death increases by 50%. The historical gold standard for the treatment of AS (Aortic stenosis) has been operation with surgical heart valve replacement (SAVR).
An open operation is a critical procedure where the surgeon opens the chest to access the heart. During the process, the center is stopped, and blood is then allowed to bypass through a heart-lung machine. With SAVR surgery, the diseased valve is removed and replaced with an artificial valve sewn into place.
SAVR has shown promising outcomes in patients who are suitable candidates for surgery. However, SAVR does have an extended recovery period that generally requires five to seven days of hospitalization after surgery, and upwards of six weeks to form a full recovery. Also, many patients require heart valve replacement but have too many other medical conditions that make them unsuitable candidates for SAVR.
TAVR is performed by placing a catheter within the femoral artery, the vast vessel within the groin. A replacement heart valve mounted on another catheter is threaded on the initial stiff wire within the blood vessel and across the diseased semilunar valve. The new valve is stationed by pushing the old valve leaflets to the side. The new valve leaflets start to function immediately.
In most cases, the procedure lasts an hour and is performed under sedation medications without general anaesthesia. Many patients are ready to be discharged the subsequent day and are usually back to regular activity within every week.
What is the clinical test evidence of TAVI/TAVR?
The initial clinical trials of TAVR began in the year 2007, evaluated TAVR in patients who were too ill to be considered for SAVR. These trials showed benefit at extending the quality and length of life in patients with severe AS. Ever since trials have been performed comparing TAVR to SAVR in patients who are considered high risk and intermediate risk for traditional SAVR. In each of these studies, TAVR has shown to be no worse or even better than SAVR. Due to the quick recovery with TAVR, it soon became the standard of taking care of intermediate and high surgical risk patients with AS.
Recently, there has been a lot of news about TAVR concerns clinical trials conducted on the healthiest patients; that is, patients who are considered low-risk surgical candidates. The PARTNER 3 trial was presented at the recent American College of Cardiology Meetings in March 2019. The PARTNER 3 trials showed significant benefits of TAVR compared to SAVR, including reduced rates of death, Stroke, and repeat hospitalizations. Thus, TAVR in low-risk patients has gained FDA approval. TAVR is considered because of the standard of care or all patients with Aortic Stenosis.
While TAVR has excellent benefits, there are certainly risks involved, as there are for any massive heart procedure. These risks may include attack, Stroke, bleeding, and need for emergency surgery, but these risks are low. Additionally, there is potential damage to the electrical system of the center, which can end within the necessity for the situation of a permanent pacemaker.
Who is eligible for the procedure?
Patients who have severe stenosis are eligible for TAVR if the operation isn't an option due to:
1. Age- elderly age >65yrs
2. Severe comorbidities, or related conditions like COPD, CKD frailty
3. Previous CVA or carotid disease patients
4. Any other condition which may make the operation too risky
5. Anatomical Consideration – Heavily calcified Av with Porcelain aorta
6. Severely depressed heart pumping function
7. Who are at increased surgical risk, have restricted mobility that will affect post‐operative rehabilitation
How is that the procedure getting to revolutionize the regular procedures?
In the last 15 years, interventional cardiology has been revolutionized by transcatheter semilunar valve implantation (TAVI). The initial promise is borne out of results from the PARTNER data from numerous real‐world registries have substantiated clinical trials, and TAVI has become the established treatment for severe, symptomatic stenosis (AS) in patients unable to undergo surgical semilunar valve replacement (AVR) thanks to prohibitive risk. The success of TAVI within this cohort has led to an expansion of its use. There is no potential for it to be administered during a broader range of patients like those with lower surgical risk or with bicuspid aortic valves (BAV). Equally, increased usage and familiarity of the procedure in recent years have enhanced understanding of potential pitfalls and sequelae. TAVI in Severe stenosis has become the "standard of care" for the treatment of high-risk and surgically inoperable patients with symptomatic AS. Consistent with the PARTNER 3 trial, which suggests that TAVI is additionally a therapeutic option in low-risk patients. TAVI/TAVR may be a boon for patients whose aortic valves have failed. Patients who have lost hope thanks to inoperable stenosis are suitable for this procedure. TAVI doesn't require heart surgery.
Advantages of TAVR over SAVR :
1. No general anesthesia in most of cases – so complications of general anesthesia & ventilation
2. No Chest Cutting or incision – no wound or bone(sternum) healing problems
3. No Cardiopulmonary Bypass – No problems of Stroke (paralysis), No Bleeding or clotting problems
4. Cardiac Muscle contractility & pumping improvement faster- patient improves faster
5. Done through 14F groin artery – closed immediately by Closure device – Pt. can walk after 6hours – No problems of ICU stay or infection
6. Immediate Discharge during a day or two from Hospital – Early recovery & back to figure
7. No need for future blood thinners (anticoagulants)
