Survival rates remained high 1 year after implantation with the transcatheter aortic CoreValve in the postmarket ADVANCE study, initial results show.
At 1 year, overall survival was 82.1% and cardiovascular survival 88.2%. This compares with survival rates of 87.4% and 91.7% at 6 months and 95.5% and 96.6% at 30 days, principal investigator Dr. Axel Linke reported at Transcatheter Cardiovascular Therapeutics 2012.
"I think they’re outstanding," he said in an interview. "If you put it into the perspective of the PARTNER A and B cohorts [in the pivotal trial in the Sapien transcatheter valve system], our mortality rate is, in absolute values, 8 to 13% lower."
One explanation is that the 1,015-patient, postmarket ADVANCE study sought out centers experienced with transcatheter aortic valve implantation (TAVI). The 44 centers in Western Europe, Asia, and South America were required to have performed at least 40 TAVI procedures, with some German centers having done as many as 500, to be certified by a TAVI proctor and to have a heart team in place.
"Clearly, our centers were out of the learning curve," remarked Dr. Linke of the University of Leipzig (Germany) Heart Center.
By comparison, some centers in the PARTNER trial of the Edwards Lifesciences Sapien valve contributed just six or seven patients and were selected based on their experience with general cardiologic intervention, he observed.
The 1-year survival rates in ADVANCE also surpass those from early registries, notably the French Aortic National CoreValve and Edwards Registry, where the initial experience with TAVI was associated with interventional mistakes, which were linked to early mortality, Dr. Linke said.
The CoreValve System has been implanted in more than 30,000 patients since its approval in the European Union in 2007, but is limited to investigational use in the United States and Japan.
No details were presented regarding mortality in various subgroups or complications such as stroke, paravalvular leaks or left bundle branch block (LBBB). A recent analysis raised concerns about LBBB, showing that one-third of 202 consecutive patients with no prior conduction disturbances developed new-onset LBBB after TAVI with a balloon-expandable valve (Sapien or Sapien XT). Although it resolved in 37.7% by hospital discharge and 57.3% at 6- to 12-month follow-up, patients with persistent LBBB had a significantly higher incidence of syncope and complete atrioventricular block requiring a permanent pacemaker (J. Am. Coll. Cardiol. 2012;60:1743-52 [doi:10.1016/j.jacc.2012.035]).
Dr. Linke said they will look at LBBB in more detailed analyses expected from ADVANCE in the coming weeks, but that there’s been no evidence of a problem with LBBB in earlier follow-up in ADVANCE or from other CoreValve users.
"Survival curves are absolutely identical up to the 6-month follow-up, so there’s no reason to believe they should be worse afterwards, although I can’t be exactly sure right now," he said, adding that in the publication, survival curves from patients with and without new-onset LBBB "started to diverge very early."
Quality of life data from ADVANCE, reported in a separate poster session at the meeting, showed significant benefits with the CoreValve, even among higher-risk patients.
Scores on the European Quality of Life–5 Dimensions (EQ-5D), which ranges from 0 (death) to 1 (perfect health), improved from 0.62 at baseline to 0.72 at 1 month, where it remained at 6 months, both highly significant differences from baseline.
On the Short Form Health Survey–12 (SF-12), scores at baseline, 1 month, and 6 months were 32.8, 39, and 39.7 for the physical component and 46.2, 48.5, and 50 for the mental component.
"Basically, whatever is gained, is gained very early from the baseline to the 1-month follow-up in the majority of the cases," said Dr. Linke.
The 322 higher-risk patients entering the study with a logistic EuroSCORE of more than 20 had significantly worse baseline health-related quality of life than did those with a EuroSCORE of 10 or less, but experienced significant improvements after TAVI on the EQ-5D at 1 month and on both components of the SF-12 at 6 months, all significant changes.
The access route used during TAVI had no impact on quality of life improvement at 6 months.
Dr. Linke reported serving as an adviser or consultant for Medtronic, which sponsored the study.