- Aortic stenosis, which involves narrowing of the aortic valve that controls blood flow from the heart to the aorta, can lead to life-threatening complications such as heart attack and stroke.
- Traditionally, open-heart surgery has been used to treat severe aortic stenosis, but for people at high risk of death and complications from invasive surgery, transcatheter aortic valve replacement ( TAVR) is preferred.
- Federal regulators have approved TAVR for the treatment of patients with aortic stenosis who are at low surgical risk, but data on long-term outcomes of this procedure are lacking.
- A new study shows that TAVR has a lower risk of death, stroke, and readmission, and a higher risk of needing a pacemaker than open-heart surgery during a 3-year follow-up period.
A recent study published in Journal of the American College of Cardiology suggest that minimally invasive transcatheter aortic valve replacement (TARV) surgery provided durable and superior clinical outcomes compared with open-heart surgery over a 3-year follow-up period.
The researchers reported that TARV significantly reduced all-cause mortality and stroke incidence and improved the performance of postoperative replacement valves compared to open-heart surgery.
“This study shows that the initial benefits of TAVR are broadly consistent over the first three years,” said lead author John Forrest, associate professor of medicine at Yale University School of Medicine in Connecticut. said in a statement, Dr. “In patients at low risk of death, stroke, or other serious complications of aortic valve surgery, we need convincing evidence that TAVR is safe, effective, and has durable results. The consistent benefit of TAVR later is not what has been observed in previous studies and provides further evidence that TAVR deserves to become the primary treatment modality for patients with aortic stenosis undergoing valve replacement. .”
The findings are significant, said Dr. Sanjiv Patel, an interventional cardiologist at the Memorial Care Heart & Vascular Institute in Orange Coast Medical Center, California.
“The most important aspect of this study is that we looked at patients at low risk of TAVR and their outcomes,” Patel said. medical news today“This study showed that TAVR was more effective than open-heart surgery in terms of mortality and stroke 3 years after new valve implantation. TAVR was also associated with higher pacemaker rates than open-heart surgery.” , further verifying what is already clinically recognized to be true.”
The aortic valve is located between the lower left chamber of the heart and the aorta, the largest artery that supplies oxygenated blood to the body. The aortic valve regulates blood flow between the left ventricle of the heart and the aorta.
Common symptoms of aortic stenosis include chest pain, shortness of breath, rapid or irregular heartbeat, and fatigue.
As the aortic valve narrows, the heart works harder and the left ventricular wall thickens compensatory.thickening of the left ventricular wall known as
In severe aortic stenosis, the defective aortic valve should be replaced. Invasive open-heart surgery, which involves an incision to access the heart, has traditionally been used to replace defective aortic valves.
Open-heart surgery, also called surgical aortic valve replacement, replaces the defective aortic valve with a new valve made of synthetic material or derived from porcine, bovine, or human heart tissue.
TAVR does not replace old bulbs. Instead, a new valve is placed inside the defective valve using a flexible, thin tube or catheter. A catheter is inserted into an artery, usually through a small incision in the leg, to deliver the replacement valve to the heart.
TAVR has replaced surgical aortic valve replacement (SAVR) in high-risk patients who cannot tolerate invasive surgery due to the risk of complications and death.
Previous studies have shown that TAVR has lower mortality in high-risk patients than SAVR. Similarly, studies in patients with moderate surgical risk have shown that TAVR has clinical outcomes that are similar or superior to open-heart surgery.
The Federal Drug Administration has approved TAVR for use in individuals under the age of 75 with severe aortic stenosis. However, there are only short-term data available comparing outcomes after TAVR with SAVR in patients with low surgical risk.
Major concerns regarding the use of TAVR include the long-term durability of the valve and the potential for paravalvular regurgitation or leakage. Paravalvular leak refers to a condition in which blood leaks back into the left ventricle due to an inadequate seal between the replacement valve and the native heart tissue.
This study was conducted as part of the Evolut LowRisk trial to evaluate long-term outcomes in patients with aortic stenosis undergoing TAVR.
The current study consisted of 1,414 participants with severe aortic stenosis who were randomly assigned to undergo TAVR or open-heart surgery. The average age of study participants was 74 years.
To compare clinical outcomes in patients undergoing TAVR or surgery, investigators assessed the incidence of all-cause mortality or stroke during the 3-year follow-up period.
They also looked at the performance of replacement valves.
During the 3-year follow-up period, the incidence of all-cause mortality or stroke was lower in patients undergoing TVAR (7%) than in the open-heart surgery group (10%). These differences in all-cause mortality and incidence of disabling stroke were consistently observed at the end of 12, 24, and 36 months.
Patients with TAVR also show a lower incidence of atrial fibrillation.
During aortic valve replacement, the size of the prosthetic valve opening becomes smaller than necessary, which can lead to an inadequate supply of blood to the body and exacerbate symptoms. This phenomenon is called prosthesis-patient mismatch.
According to research,
In the current study, individuals undergoing open-heart surgery (25%) had more than twice as many cases of moderate-to-severe prosthesis-patient mismatch than those undergoing TAVR (10%).
Echocardiography also revealed significantly improved aortic valve function after TAVR over open-heart surgery. Both groups showed improvements in quality of life, but these improvements were more rapid in the group that received TAVR.
A previous study showed that moderate to severe paravalvular leakage after TAVR was associated with increased mortality 5 years after the intervention. In the current study, the incidence of moderate and severe paravalvular regurgitation was similar in patients in the TAVR and open-heart surgery groups.
However, mild paravalvular leakage or regurgitation was more commonly observed in participants undergoing TVAR (20%) than open heart surgery (2%). Individuals with mild paravalvular leak on day 30 were not at increased risk of death or disabled stroke by the end of the follow-up period.
The heart’s conduction system contains specialized muscle cells that transmit electrical impulses through the heart, causing the heart chambers to contract and controlling the heartbeat.
Valve placement during TAVR can damage the heart’s conduction system, and patients often require a new pacemaker after TAVR.
Consistent with this, the number of individuals requiring pacemaker placement was higher in the TAVR group (23%) than in the surgery group (9%). Patients who had a pacemaker implanted within 30 days after TAVR had a higher mortality rate than those who did not require a pacemaker.
The type of prosthetic valve used for TAVR in this study may also limit access to the coronary arteries that supply blood to the heart muscle.
Providence Interventional Cardiologist Michael Broukhim, Ph.D. St. John’s Health Center in California, which was not involved in the study, said: medical news today.
“The researchers intend to follow patients for a total of 10 years to fully understand the long-term risks and benefits after TAVR,” he added. “The significance of this study is that the 3-year outcomes of TAVR and surgical aortic valve replacement appear to be comparable. Therefore, long-term follow-up data will be important to evaluate the optimal treatment for low-risk patients.”
Dr. Nish Harshadkumar Patel, an interventional cardiologist at the Miami Cardiac and Vascular Institute, part of Baptist Health South Florida, who was not involved in the study, said: medical news today “Physicians can consider this finding when educating patients and engaging in shared decision-making regarding TAVR and surgical selection for aortic valve replacement in low-risk patients.”