Transcatheter aortic valve replacement (TAVR) in bicuspid aortic stenosis (AS) was effective and without paravalvular aortic regurgitation (AR), according to a multicenter study published in JACC: Cardiovascular Interventions.
TAVR is typically contraindicated for bicuspid AS, particularly in light of paravalvular AR risk. While bicuspid AS typically occurs in younger patients, bicuspid valves are still a significant cause of symptomatic aortic stenosis (AS) in elderly patients considered for TAVR or surgical AVR.
Researchers hypothesized that newer-generation valves, such as the SAPIEN 3 (Edwards Lifesciences; Irvine, CA), may offer advantages compared to previous valves. They collected patient data from 8 centers in Canada, Germany, Italy, France, and Switzerland. All patients were treated with SAPIEN 3 devices between June 2012 and July 2015.
Clinical end points included procedural and 30-day mortality.
Bicuspid aortic valve stenosis was identified in 51 patients (mean age: 76.2 ± 9.3; 52.9% women) with an average Society of Thoracic Surgeon Predicted Risk of Mortality score of 5.2 ± 3.7%. A majority of patients (n=49; 96.1%) had TAVR performed via the femoral route and just 2 patients via the transcarotid route. No intraprocedural deaths occurred and there were no device malposition events that required additional intervention.
At 30 days, the mean aortic gradient was reduced from 49.4 ± 16.0 mm Hg to 11.2 ± 4.7 mm Hg, and the aortic valve area was increased from 0.7 ± 0.2 cm2 to 1.7 ± 0.3 cm2. There was no AR or trivial AR in 63% of patients and mild AR in 37% of patients. No moderate or severe AR was present in any of the patients. Researchers noted a tendency of the valve to expand asymmetrically when viewed by angiography in 38% of patients. However, AR rates or need for pacemaker were not higher in patients with a degree of asymmetry >7%.
Researchers recorded 2 deaths after 30 days. One patient died on day 14 after a procedure-related tamponade led to gradual deterioration, and another patient died on day 27 from aspiration after general deterioration. Of the 5 patients who experienced major or life-threatening bleeding, 3 were directly related to the procedure. Finally, new pacemakers were implanted in 12 patients. A low implantation position of the valve frame (defined as >8 mm below annulus level) was associated with a need for pacemaker implantation.
“To the best of our knowledge, this is the largest report of bicuspid patients treated with the SAPIEN 3 valve, and the only report of patients treated exclusively with this device,” researchers wrote. “The device success rate of 98% reported here is comparable to that reported with the same next-generation valve in patients with tricuspid aortic valves.”
They noted that only 4 patients (7.6%) required post-implantation balloon dilation due to residual paravalvular regurgitation, which is a relatively low rate compared to other recent reports of 18% to 30%. The low profile and improved accuracy of positioning with the SAPIEN 3 system, as well as operator experience and case planning, may have attributed to the high success rate, according to the researchers.
Researchers also pointed out that previous studies have included patients treated with self-expanded valves, which are more capable of conforming to the “irregular orifice of the bicuspid valve,” but are not as capable of achieving circular formation after implantation.
Using a new-generation TAVR device in patients with bicuspid aortic valve stenosis appears to be clinically promising. Given that pacemaker implantation after TAVR in bicuspid AS were still relatively high, researchers urged for further study to understand the mechanism behind it.
Perlman GY, Blanke P, Dvir D, et al. Bicuspid aortic valve stenosis. Favorable early outcomes with a next-generation transcatheter heart valve in a multicenter study. JACC Cardiovasc Interv. 2016;9(8):817-824. doi: 10.1016/j.jcin.2016.01.002.