Outcomes of Veterans Undergoing TAVR Within Veterans Affairs Medical Centers: Insights From the Veterans Affairs Clinical Assessment, Reporting, and Tracking Program

Monitored Anesthesia Care Versus General Anesthesia for Transcatheter Aortic Valve Replacement

OBJECTIVE

Monitored anesthesia care (MAC) has been increasingly used in lieu of general anesthesia (GA) for transcatheter aortic valve replacement (TAVR). We sought to compare outcomes and in-hospital costs between MAC and GA for TAVR at a Veterans Affairs Medical Center.

METHODS

A single-center retrospective review was performed of 349 patients who underwent transfemoral TAVR (MAC, n = 244 vs GA, n = 105) from January 2014 to December 2019. Baseline patient characteristics, operating room (OR) time, intensive care unit (ICU) length of stay (LOS), and cost, total LOS, hospital cost, total cost, and complication rates were collected. Propensity matching was performed and resulted in 83 matched pairs.

RESULTS

In the unmatched TAVR cohort, MAC TAVR was associated with reduced OR time (146 vs 198 min, P < 0.001), ICU LOS (1.4 vs 1.8 days, P < 0.001), total hospital LOS (3.4 vs 5.4 days, P < 0.001), and lower index total cost ($81,300 vs $85,400, P = 0.010). After propensity matching, MAC TAVR patients had reduced OR time (146 vs 196 min, P < 0.05), ICU LOS (1.2 vs 1.7 days, P = 0.006), total LOS (3.5 vs 5.1 days, P = 0.001), and 180-day mortality (2.4% vs 12%, P < 0.03). There was no difference in total hospitalization cost or total cost.

CONCLUSIONS

In propensity-matched groups, TAVR utilizing MAC is associated with improved OR time efficiency, decreased LOS, and a reduction in 180-day mortality but no significant difference in cost.

Midterm Durability and Structural Valve Degeneration of Transcatheter Aortic Valve Replacement in a Federal Facility

OBJECTIVE

Transcatheter aortic valve replacement (TAVR), previously reserved for patients of intermediate to prohibitive surgical risk, has now been expanded to patients of any surgical risk with severe aortic stenosis. Bioprostheses are prone to structural valve degeneration (SVD), a progressive and multifactorial process that limits valve durability. As the population undergoing TAVR shifts toward a lower-risk and younger profile, long-term durability is a crucial determinant for patient outcomes. Our objective was to determine the incidence and risk factors of SVD at midterm follow-up in a veteran TAVR population.

METHODS

Patients undergoing TAVR at our federal facility were retrospectively evaluated for SVD and other endpoints with standardized consensus criteria. Multivariable Cox proportional hazards analysis was performed to evaluate risk factors for mortality and SVD.

RESULTS

From 2013 to 2020, 344 patients (median age, 78 years) underwent TAVR. Survival from all-cause mortality was 91.3% at 1 year, 75.1% at 3 years, and 61.7% at 5 years. Cumulative freedom from SVD was 98.2% at 1 year, 96.5% at 3 years, and 93.7% at 5 years. All 13 patients with SVD met hemodynamic criteria, and 1 required intervention. Median time to hemodynamic SVD was 1.04 years. Independent risk factors for SVD included age (hazard ratio [HR] = 0.92, 95% confidence interval [CI]: 0.86 to 0.99) and valve size (HR = 0.19, 95% CI: 0.04 to 0.89).

CONCLUSIONS

SVD was evident at a low but detectable rate at 5-year follow-up. Further understanding of TAVR biomechanics as well as continued longer-term follow-up will be essential for informing patient-specific risk of SVD.

Dissemination of Transcatheter Aortic Valve Replacement in the United States

BACKGROUND

Societal guidelines and payor coverage decisions for transcatheter aortic valve replacement (TAVR) attempt to strike a balance between providing access and maintaining quality. The extent to which dissemination of TAVR has achieved these ideals remains unknown.

OBJECTIVES

This study sought to define patterns of TAVR dissemination in the United States and their influence on outcomes.

METHODS

Using data from the TVT (Transcatheter Valvular Therapy) registry, this study identified TAVR sites from 2011 to 2018 and calculated drive-times from existing to new sites. In a contemporary cohort, this study compared site and patient characteristics by annual case volume and density of sites per million Medicare beneficiaries. Using hierarchical regression and Cox methods, this study determined the association between case volumes, site density, and changes in volume and density with patient risk profiles and outcomes.

RESULTS

TAVR sites participating in the TVT registry increased from 198 to 556 from 2011 to 2018. Median drive-time from existing to new sites decreased from 403 minutes (interquartile range: 211-587 minutes) to 26 minutes (interquartile range: 17-48 minutes). In a contemporary cohort, higher site density was associated with lower procedural risk as well as with an increased hazard of 30-day risk-adjusted mortality (P = 0.017). Similarly, longitudinal increases in site density over time were associated with a higher hazard of 30-day (P = 0.011) and 1-year (P = 0.013) mortality.

CONCLUSIONS

TAVR has expanded significantly over time, but with regional clustering of sites. Although procedural risk is lower at higher density sites, these sites demonstrate an increased hazard of mortality. These findings suggest that the expansion of TAVR services in the United States may have had unintended consequences on procedural quality.

Left Ventricle Mass Regression After Surgical or Transcatheter Aortic Valve Replacement in Veterans

BACKGROUND

Differences in left ventricular mass regression (LVMR) between transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR) have not been studied. We present clinical and echocardiographic data from veterans who underwent TAVR and SAVR, evaluating the degree of LVMR and its association with survival.

METHODS

We retrospectively reviewed TAVR (n = 194) and SAVR (n = 365) procedures performed in veterans from 2011 to 2019. After 1:1 propensity matching, we evaluated mortality and secondary outcomes. Echocardiographic data (median follow-up 957 days, interquartile range 483-1652 days) were used to evaluate LVMR, its association with survival, and predictors of LVMR.

RESULTS

There was no difference between SAVR and TAVR patients in mortality (for up to 8 years), stroke at 30 days, myocardial infarction, renal failure, prolonged ventilation, reoperation, or structural valve deterioration. SAVR patients (67.3% [101 of 150]) were more likely to have LVMR than TAVR patients (55.7% [44 of 79], P = .11). The magnitude of LVMR was greater for the SAVR patients (median, -23.3%) than for the TAVR patients (median, -17.8%, P = .062). SAVR patients with LVMR had a survival advantage over SAVR patients without LVMR (P = .016). However, LVMR was not associated with greater survival in TAVR patients (P = .248).

CONCLUSIONS

SAVR patients were more likely to have LVMR and had a greater magnitude of LVMR than TAVR patients. LVMR was associated with better survival in SAVR patients, but not in TAVR patients.

Recommendations for strengthening the role of embedded researchers to accelerate implementation in health systems: Findings from a state-of-the-art (SOTA) conference workgroup

BACKGROUND

Traditional research approaches do not promote timely implementation of evidence-based innovations (EBIs) to benefit patients. Embedding research within health systems can accelerate EBI implementation by blending rigorous methods with practical considerations in real-world settings. A state-of-the-art (SOTA) conference was convened in February 2019 with five workgroups that addressed five facets of embedded research and its potential to impact healthcare. This article reports on results from the workgroup focused on how embedded research programs can be implemented into heath systems for greatest impact.

METHODS

Based on a pre-conference survey, participants indicating interest in accelerating implementation were invited to participate in the SOTA workgroup. Workgroup participants (N = 26) developed recommendations using consensus-building methods. Ideas were grouped by thematic clusters and voted on to identify top recommendations. A summary was presented to the full SOTA membership. Following the conference, the workgroup facilitators (LJD, CDH, NR) summarized workgroup findings, member-checked with workgroup members, and were used to develop recommendations.

RESULTS

The workgroup developed 12 recommendations to optimize impact of embedded researchers within health systems. The group highlighted the tension between "ROI vs. R01" goals-where health systems focus on achieving return on their investments (ROI) while embedded researchers focus on obtaining research funding (R01). Recommendations are targeted to three key stakeholder groups: researchers, funders, and health systems. Consensus for an ideal foundation to support optimal embedded research is one that (1) maximizes learning; (2) aligns goals across all 3 stakeholders; and (3) implements EBIs in a consistent and timely fashion.

CONCLUSIONS

Four cases illustrate a variety of ways that embedded research can be structured and conducted within systems, by demonstrating key embedded research values to enable collaborations with academic affiliates to generate actionable knowledge and meaningfully accelerate implementation of EBIs to benefit patients.

IMPLICATIONS

Embedded research approaches have potential for transforming health systems and impacting patient health. Accelerating embedded research should be a focused priority for funding agencies to maximize a collective return on investment.

Development of the Minimalist Approach for Transcatheter Aortic Valve Replacement at a Veterans Affairs Medical Center

OBJECTIVES

While a minimalist transcatheter aortic valve replacement (TAVR) approach has shown safety and efficacy at civilian hospitals, limited data exist regarding developing this approach at Veterans Affairs (VA) medical centers (VAMCs). We implemented TAVR with minimalist approach (MA) using conscious sedation (CS) with transthoracic echocardiography (TTE) and compared safety and outcomes with general anesthesia (GA) with transesophageal echocardiography (TEE) at a university-affiliated VAMC.

METHODS

A total of 258 patients underwent transfemoral TAVR at a VAMC between November 2013 and October 2019. Ninety-three patients underwent GA/TEE and 165 patients underwent CS/TTE with dexmedetomidine and remifentanil. Propensity-score matching with nearest-neighbor matching was used to account for baseline differences, yielding 227 participants (81 GA, 146 CS).

RESULTS

MA-TAVR had no effect on 30-day mortality or paravalvular leakage. No differences were found in permanent pacemaker implantation, major vascular complications, or postoperative hemodynamics. In this population, MA-TAVR did not reduce procedural time, hospital length of stay, or intensive care unit length of stay.

CONCLUSIONS

Unlike civilian hospitals, MA with CS/TTE did not reduce overall length of stay in the veteran population; however, it was safe and effective for transfemoral TAVR without impacting clinical outcomes of mortality, major vascular complications, and paravalvular leakage.