The TAVR heart procedure was granted FDA approval in 2012 for patients whose risk of death after surgery was greater than 15%. Newer clinical evidence for TAVR has shown that it may be an effective alternative to open heart valve replacement surgery in lower risk patients as well, and potentially in individuals with other heart valve conditions. Interventional cardiologist Dr. Tim Issac explains the history of TAVR and reviews what newer clinical evidence has demonstrated since the approval of TAVR.
In this Article:
History of the TAVR heart procedure and the landmark PARTNER study
Comparison of clinical outcomes between TAVR and open heart valve replacement surgery in high and low surgical risk patients with aortic valve stenosis
Emerging data on the efficacy of the TAVR procedure in other valvular heart diseases
History of the TAVR Heart Procedure
Transcatheter aortic valve replacement (TAVR) exploded onto the scene of cardiac medicine shortly after the turn of the millennium.¹ At that time, aortic valve stenosis was a fairly well understood disease, yet the only treatment options were open heart surgery to replace the valve or optimizing medications to minimize the negative impact of the stenosed valve. Unfortunately, medications are merely a “band-aid” fix, as there are no current medication options to delay the progression of valve disease. Then in 2002, the first TAVR procedure was performed in a patient who could not undergo surgery, demonstrating that a new option should be considered for these patients. Still the technology and skills to perform TAVR took time to develop.
It wasn’t until 2012 that the FDA approved TAVR for patients who are “high surgical risk”, or those patients whose risk of death after surgery was greater than 15%. The landmark PARTNER study was revolutionary in the treatment of aortic stenosis because it demonstrated conclusively that TAVR was better than medications in surgically inoperable patients, and TAVR was better than surgery in high risk patients with symptomatic aortic stenosis.² The technology and procedural skills have only improved since the first TAVR was performed, and now we have evidence that TAVR may be appropriate in other patient populations.
TAVR Procedure Versus Open Heart Valve Replacement Surgery
As noted above, TAVR has been compared to medical management and to open heart valve replacement surgery, but the nuances of those comparisons are important to consider. In the PARTNER trials, TAVR was compared to medical management in surgically inoperable patients, and it was compared to surgical valve replacement in high risk patients. So while the data is useful in these two groups, the study can’t tell us anything about TAVR in other groups of patients, such as those with intermediate surgical risk. It also doesn’t tell us about how new devices and techniques have changed outcomes. Additionally, these studies focused on patients with classic age-related aortic stenosis, and did not include patients with other reasons for needing an aortic valve replaced, like bicuspid aortic valve or even aortic regurgitation.
Fortunately, the data from a handful of large and well-designed studies has become available within the past couple years.³⁻⁴ These studies are answering questions about the benefit of TAVR versus surgery even in patients with lower surgical risks, and the data is also showing improvement in second generation valves compared to the valves used in the first PARTNER trial.
So what do we know now? We know that second generation valves have new features that increase first time success rates and decrease short- and long-term complications. TAVR is also beginning to show favorable outcomes in lower surgical risk patients. At this time, it’s hard to say which is better because long-term mortality seems equal between the two, and each has its benefits. Compared to surgical replacement, TAVR procedures resulted in a lower risk of bleeding, shorter hospital length of stay, and faster recovery.³ However there remains a concern that patients who underwent TAVR are at higher risk of other adverse events, like vascular complications, regurgitation around the new valve, or the need for a new pacemaker.⁴ Some smaller trials are beginning to demonstrate a clearer benefit of TAVR, but more data is needed to confirm.
Expanding Indications for the TAVR Heart Procedure
It’s an exciting time in cardiac medicine because the technology and skills of procedural cardiologists continue to improve. New data is also coming out every day arguing to expand the indications for TAVR to increasingly lower risk surgical patients,⁵ or those with aortic stenosis due to a bicuspid valve,⁶ or even to aortic regurgitation.⁷ At the same time, minimally invasive surgical techniques have been developed with favorable results, but they have not yet been studied against TAVR. With all the new data, the differences between TAVR and surgery are becoming smaller and smaller, which can make it hard to decide on the best treatment. Sometimes, the data clearly points to the better alternative, as in high surgical risk patients. But for many patients who are looking for an alternative to surgery, the answer may be less clear.
To know where your case fits, it’s important to find a comprehensive Heart Team that carefully weighs the risks and benefits of TAVR vs. open heart valve replacement surgery. Schedule a consultation with Premier Cardiovascular Care to learn more about valvular heart disease and your options.
About the Author
Dr. Tim T. Issac is a practicing interventional cardiologist with Premier Cardiovascular Care in the Dallas, TX metroplex. Dr. Issac has been in private practice since 2011 and specializes in minimally invasive cardiovascular interventions. You can view Dr. Issac's full bio here.
This article was written with research and editorial assistance from OnChart.
References
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[7] Haddad A, Arwani R, Altayar O, Sawas T, Murad MH, De marchena E. Transcatheter aortic valve replacement in patients with pure native aortic valve regurgitation: A systematic review and meta-analysis. Clin Cardiol. 2019;42(1):159-166.