TAVI Improves Heart Function and Exercise Capacity
German researchers report success with transcatheter aortic valve
implantation (TAVI) in patients with low-flow, low-gradient aortic
stenosis—a special form of aortic stenosis that is difficult to treat.
Results published in the April issue of Catheterization
and Cardiovascular Interventions, the peer-reviewed journal of
the Society for Cardiovascular Angiography and Interventions (SCAI),
show that while all-cause mortality was high within the first six
months, TAVI significantly improved heart function and exercise capacity
in surviving patients.
While low-flow, low-gradient aortic stenosis occurs in only 5% of
patients with aortic stenosis, treatment of these patients remains
challenging. Previous research shows a more discouraging prognosis for
patients receiving conservative therapy and higher mortality following
surgical aortic valve replacement. Over the past few years, TAVI has
been used as an alternative treatment for patients with severe aortic
stenosis or in those deemed a high surgical risk.
A team led by Dr. Michael Gotzmann, with the University-Hospital
Bergmannsheil in Bochum, Germany performed TAVI in 167 consecutive
patients with severe aortic stenosis and high operative risk between
June 2008 and December 2010. Of those participating, 15 patients had
low-flow, low-gradient aortic stenosis and the remaining 152 patients
were part of the control group. Interventionists used the Medtronic
CoreValve prosthesis 18-F generation for this study.
Within the first 6 months following TAVI, 25 patients died—13% without
and 33% with low-flow, low-gradient aortic stenosis. These patients had
a higher all-cause mortality following TAVI compared to patients without
this severe form of disease. However, the surviving 10 patients with
low-flow, low-gradient aortic stenosis reached the 6-month mark, and
after nearly a year post-procedure no additional death, myocardial
infarction, or stroke occurred.
Furthermore, the surviving patients displayed a significant improvement
in heart function and exercise capacity. “While there is a high
mortality rate in this difficult-to-treat patient group, there is
symptomatic benefit for patients undergoing TAVI therapy,” said Dr.
Gotzmann. The authors suggest the high mortality rate could be due to
pre-existing conditions that place patients are greater risk
post-procedure. “Further multi-center studies in larger patient
populations are needed to understand the potential benefit of TAVI in
patients with low-flow, low-gradient aortic stenosis,” concludes Dr.
Gotzmann.
