Study Details Incidence, Mortality Trends Related to Surgical Explantation in TAVR Patients

October 17, 2020

A Brigham and Women's-led study details trends in incidence, characteristics, and outcomes of surgical explantation following TAVR among patients in the US.

A new study is offering clinicians an updated overview of trends related to surgical explanation after transcatheter aortic valve replacement (TAVR).

Results of the study, which was led by a team of investigators from the Division of Cardiac Surgery at Brigham and Women’s Hospital, detail a low incidence, but high mortality rates when examining surgical explantation following TAVR—stressing the importance of developing a greater understanding of outcomes and mechanisms behind explantation.

With their study objective in mind, a team of investigators, which includes Practical Cardiology advisory board members Tsuyoshi Kaneko, MD, and Sameer Hirji, MD, conducted their analysis using data obtained from the Medicare Provider Analysis Review and Master Beneficiary Summary File for TAVR procedures performed from 2012-2017. In total, 132,633 patients were identified for inclusion in the current analysis.

TAVR patients were excluded if they were not discharged alive, were discharged to hospice, underwent surgical procedures, surgical explantation, or TAVR-in-TAVR during the index TAVR admission, or if they underwent TAVR-in-TAVR subsequently during the observation period.

The primary outcomes of interest chosen for the analysis included incidence of surgical explantation of TAVR valve, time to surgical explant, and 30-day and 1-year mortality. Secondary outcomes included etiology/indication for surgical explantation, bleeding complications, acute kidney injury, permanent stroke, intensive care unit (ICU) stay, hospital length of stay (LOS), and the proportion of bioprosthetic versus mechanical valves used.Of note, post-operative survival was assessed using time-dependent Cox proportional hazard regression analysis and landmark analysis.

Upon analysis, surgical explantation occurred in 0.2% (n=227) patients. Investigators pointed out the incidence of explantation was 0.28% in the early TAVR era and 0.14% in the newer TAVR era. Results of the analysis indicated the median time to surgical explant was 212 days. For patients who underwent surgical explantation, 8.8% occurred within 30 days of TAVR, 46.3% occurred within 6 months, and 70.9% occurred within the first year.

In comparison to patients who did not experience a surgical explantation, the explant cohort was significantly younger (mean age 73.7 vs 81.7 years), had a lower prevalence of heart failure (55.9% vs 65.8%), and were more likely to have a lower-risk profile (15% vs 2.4%) (P for all <.05). Among patients who underwent surgical explantation, the 30-day and 1-year mortality rates were 13.2% and 22.9%, respectively.

Investigators pointed out 30-day and 1-year mortality rates did not vary by time to surgical explant, TAVR era, or between patients with versus without endocarditis (P >.05). In the time-dependent Cox regression analysis, results suggested mortality was greater among patient s with surgical explantation (HR, 4.03; 95% CI, 1.81-8.98). Additionally, results demonstrated indication, time-to-surgical-explant, and year of surgical explantation were not associated with worse post-explantation survival (P for all >.05).

“The present study provides updated evidence on the incidence, timing, and outcomes of surgical explantation of a TAVR prosthesis. Although the overall incidence was low, short-term mortality was high,” wrote study investigators. “These findings stress the importance of future mechanistic studies on TAVR explantation and may have implications on lifetime management of aortic stenosis, particularly in younger patients.”

This study, “Incidence, Characteristics, Predictors, and Outcomes of Surgical Explantation After Transcatheter Aortic Valve Replacement,” was published in the Journal of the American College of Cardiology.