Partner 3 Trial shows new clinical data suggesting that TAVI may benefit more patients with Aortic Stenosis

Aortic Stenosis is a common heart valve condition that is associated with alarming mortality rates at 5 years if left untreated¹.

Until recently, there has only been data supporting Transcatheter Aortic Valve Implantation (TAVI) for those patients classified as high risk for the traditional Surgical Aortic Valve Replacement (SAVR). However, the recent Partner 3 Trial² demonstrates a benefit for those patients considered to be at low risk for SAVR.

Dr John Webb, a pioneer in the field of transcatheter therapies, discusses the trial data with Interventional Cardiologist, Dr Karl Poon from St Andrew’s War Memorial Hospital, and the Queensland Heart Institute.

Dr Webb begins by stating “the results really were wonderful and even as one of the investigators we did not expect to do this well, we thought we may see non-inferiority but the degree of superiority was a surprise. We did see a dramatic reduction in death and stroke rates at 30 days, roughly half when compared to surgery… However, we need to keep things in perspective, these were very good TAVI candidates against very good surgical candidates.”

Dr Webb goes further to state “there are some patients who are just better off having a surgical procedure and it is important not to forget that.” It’s widely accepted that some patients who require other cardiac surgical procedures may benefit from one surgical intervention as opposed to multiple surgeries.

Minimally invasive therapies are often attributed to faster recovery times and potential cost savings due to a reduction in hospitalisation. One issue that’s less clear, is the longevity or durability of transcatheter valves in-vivo situations as these patients age.

The current Australian guidelines support TAVI only for patients who have been identified as high risk for surgical intervention after an assessment from specialised heart teams³.

Dr Webb states “it is looking as though TAVI valves are going to be more durable, certainly we have patients out to 10 years now, but like all tissue valves they will fail eventually.”

A recent publication in Interventional Cardiology⁴ supported this opinion but states that “the first studies reporting on structural valve degradation up to 8 years after TAVI showed very low rates of transcatheter aortic valve degradation comparing favourably with surgical counterparts.”

This may lead Cardiology teams to now consider new issues regarding low-risk patients who may be more suited to a surgical valve because of its durability and longevity, patient age or what alternatives may be pertinent regarding valve replacement, as the valve eventually degrades. One option may be considering a new TAVI valve in a failing TAVI valve procedure as opposed to an entirely new surgical approach. These considerations may depend on a range of factors such as a patient’s comorbidities, coronary vessel anatomy and activity levels amongst other factors.

While this may be exciting news for patients requiring Aortic Stenosis treatment, the current guidelines do not include patients classified as intermediate or low risk for surgical procedures.

Sources:
Heart.org
The England Journal of Medicine
Australian Government, Medical Services Advisory Committee
National Centre for Biotechnology Information

Our conversation with Professor John Webb and Dr Karl Poon will be available in full on MEDD coming soon.

Interview conducted: August 2019

Written by Shane Bassett RN, BN. CCRN
Clinical Content Manager – Connect The Docs

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