No Change Seen in European TAVR Clinical Use Patterns

SAN FRANCISCO, CALIF.—Evidence in recent years indicates all the rules of TAVR in Europe are being broken, with physicians there performing TAVR in low-risk patients. However, to more precisely assess “risk creep,” accurately measuring risk is important, according to Martyn R. Thomas, MD, of St. Thomas’ Hospital, London.

During his presentation, Thomas said that more patients with aortic stenosis are receiving some form of treatment, and “risk creep” can reflect an inappropriate increase in low-risk patients or reduced high-risk patients receiving TAVR.

“We have to be able to [accurately] measure risk, and this is a problem because both the Logistic EuroSCORE and STS [Society of Thoracic Surgeons risk model] are far from ideal,” Thomas said.

According to Thomas, in the PARTNER trial, STS scores had little value at 30 days, but they did distinguish outcomes in the various patients at 2 years. The EuroSCORE, on the other hand, was “completely useless” in Cohort B of the PARTNER trial, according to Thomas.

“The Logistic EuroSCORE grossly overestimates risk in high-risk populations,” Thomas said, adding that despite the overestimation, he would not dismiss it completely because it categorizes risk.

Using the EuroSCORE to review two cohorts separated by time in the SOURCE Registry, European TAVR patients treated using the Edwards Sapien bioprosthesis were evaluated during the first 2 years after commercialization. Data on 2,307 patients were analyzed with little evidence found of “risk creep.”

“There was a reduction in patients in the Logistic EuroSCORE of greater than 20 and an increase of less than 20. This may be a lesson in what not to do and excluding the very high-risk patients. Interestingly, we started to see those patients having valve-in-valve therapies,” Thomas said (see Figure).

Some of the more common reasons for performing TAVR in patients with an STS score of less than 20 included presence of a porcelain aorta, cancer, pulmonary disease and post-thoracic radiation therapy.

Ultimately, Thomas said the optimal way to deliver TAVR is with a multidisciplinary team with the surgeon as the gatekeeper. “Within this environment, the availability of TAVR improves the results of surgical aortic valve replacement,” Thomas said.  “The regulatory environment of any country will dictate the degree of risk creep.”