There was a low prevalence of prosthesis-patient mismatch and mortality 1 year in patients who underwent transcatheter aortic valve replacement, according to a study published in JACC: Cardiovascular Interventions.
“These findings imply that [prosthesis-patient mismatch] is not a risk factor for mortality in Asian patients who have undergone TAVR,” Masaki Miyasaka, MD, of the Cardiovascular Center at Sendai Kosei Hospital in Japan, and colleagues wrote.
High-risk Japanese cohort
Researchers analyzed data from 1,546 Japanese patients (median age, 85 years; median body surface area, 1.41 m2) who were high risk for surgery, had severe aortic stenosis and underwent TAVR between October 2013 and July 2016. Exclusion criteria included death after TAVR before hospital discharge, absence of transcatheter heart valve from migration of transcatheter heart valve or delivery failure, conversion to surgical AVR and unreliable echocardiographic data.
The valves used in these patients included Sapien XT (Edwards Lifesciences), Sapien 3 (Edwards Lifesciences) and CoreValve (Medtronic). Patients received the devices through the trans-subclavian, transfemoral, transapical or transaortic approaches.
Echocardiograms were performed before TAVR and at discharge. A postprocedural echocardiogram was also done to assess for prosthesis-patient mismatch, which was categorized by effective orifice area of the prosthetic valve: none or mild (> 0.85 cm2/m2), moderate (0.65 cm2/m2-0.85 cm2/m2) and severe (< 0.65 cm2/m2).
Primary endpoints were CV and all-cause mortality at 1 year. The secondary endpoint included rehospitalization for congestive HF at 1 year.
Moderate prosthesis-patient mismatch occurred in 8.9% of patients, and 0.7% had severe prosthesis-patient mismatch.
Independent predictors of mismatch
In the logistic multivariate regression analysis, independent predictors of prosthesis-patient mismatch included larger body surface area, younger age, smaller annulus area, smaller aortic valve area, the use of the Sapien 3 valve and no balloon postdilatation.
At 1 year, there was no difference in all-cause mortality in patients with prosthesis-patient mismatch (10.2%) and those without it (8.3%; log-rank P = .41).
More patients with prosthesis-patient mismatch were hospitalized for congestive HF at 1 year than those without prosthesis-patient mismatch (15% vs. 67%; P = .002), although it was not an independent predictor in multivariate analysis.
“These results indicate that a smaller [body surface area] is associated with better survival in patients with [prosthesis-patient mismatch] in this study,” Miyasaka and colleagues wrote. “The reasons behind the better survival in patients with [prosthesis-patient mismatch] with a small [body surface area] is unknown. However, it should be taken into account that the relationship between cardiac output and [body surface area] is not linear, but rather follows an allometric relationship characterized by its power (exponent).”
In a related editorial, Bernard D. Prendergast, DM, of the King’s College London British Heart Foundation Centre of Excellence at the Rayne Institute at St. Thomas’ Hospital Campus in London, and Hannah Z.R. McConkey, MA, of the department of cardiology at Guy’s and St. Thomas’ NHS Foundation Trust in London, wrote: “This study ... provides further assurance that TAVR is a safe and effective alternative to [surgical] AVR and may in fact offer particular advantages in populations at identified risk for [prosthesis-patient mismatch]. Indeed, despite small annular dimensions, patients of small stature are at lower risk for [prosthesis-patient mismatch], provided that meticulous valve sizing is incorporated into preprocedural imaging protocols. Consistent with recent European guidelines, such anatomic considerations should be incorporated into heart team discussions concerning the optimal treatment option for all patients with aortic stenosis at increased surgical risk.” – by Darlene Dobkowski
Disclosures: Miyasaka, Prendergast and McConkey report no relevant financial disclosures. Please see the study for all other authors’ relevant financial disclosures.