Publications

The evidence base evaluating the use of mechanical circulatory support (MCS) devices in complex, high-risk percutaneous coronary intervention is evolving from a small number of randomised clinical trials to incorporate an amassing body of real-world data. Due to both the growing incidence of the procedures and the limitations of the evidence, there is wide variability in the use of MCS, and the benefits are actively debated. The goal of this review is to perform an integrated analysis of randomised and non-randomised studies which have informed clinical and regulatory decision-making in contemporary clinical practice. In addition, we describe forthcoming studies that have been specifically designed to advance the field and resolve ongoing controversies that remain unanswered for this complex, high-risk patient population.

BACKGROUND: Food and Drug Administration-mandated postmarket studies for transcatheter aortic valve replacement in low-risk populations plan to use passively collected registry data linked to claims for long-term follow-up out to 10 years. Therefore, it is critically important to understand the validity of these claims-based end points. We sought to evaluate the ability of administrative claims with International Classification of Diseases-Tenth Revision (ICD-10) codes to identify trial-adjudicated end points and reproduce treatment comparisons of aortic valve replacement in the Evolut Low Risk Trial.

METHODS: We linked Evolut Low Risk trial patients to the Medicare Provider Analysis and Review database. We calculated sensitivity, specificity, positive predictive value, negative predictive value, and κ agreement statistic of claims to detect clinical end points through 2 years in trial patients. We additionally compared end points across treatment arms using trial-adjudicated outcomes versus claims-based outcomes.

RESULTS: Trial-adjudicated deaths were perfectly identified by claims. Claims had good performance in identifying trial-adjudicated disabling stroke (sensitivity 68.8%, specificity 99.0%, positive predictive value 64.7%, negative predictive value 99.1%, κ=0.66) and pacemaker placement (sensitivity 85.2%, specificity 98.4%, positive predictive value 90.4%, negative predictive value 97.5%, κ=0.86), but more modest performance in identifying trial-adjudicated myocardial infarction (κ=0.46) and vascular complications (κ=0.45). There was no difference between treatment arms for the primary end point of death or disabling stroke using trial data (hazard ratio, 0.83 [95% CI, 0.41-1.68]) or claims data (hazard ratio, 0.89 [95% CI, 0.43-1.81]; interaction P=0.71).

CONCLUSIONS: Claims-based end points performed well in ascertaining death, disabling stroke, and pacemaker placement and were able to reproduce principal trial findings. These results support the selective use of claims-based end points for transcatheter aortic valve replacement postmarketing surveillance.

REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02701283.

BACKGROUND: Recent data support both surgical-first and endovascular-first revascularization approaches for chronic limb-threatening ischemia (CLTI), but hospital-based practices are poorly described.

OBJECTIVES: This aim of this study was to characterize contemporary variations and outcomes associated with each strategy among U.S. hospitals providing both approaches.

METHODS: Medicare beneficiaries ≥66 years of age with CLTI treated at institutions offering both strategies between October 1, 2015 to December 31, 2021 were analyzed. A marginal Cox regression approach was used, and models were adjusted for patient-level covariates.

RESULTS: Among 196,070 patients at 1,832 institutions, 82.5% underwent endovascular treatment. Patients undergoing endovascular revascularization were older and had a higher comorbidity burden. The adjusted median OR for receiving an endovascular procedure was 2.32 among hospitals (Q1-Q3: 2.24-2.40; P < 0.01), demonstrating high variability in intervention use. Patients undergoing endovascular revascularization at the highest quintile hospitals had a lower rate of major amputation (adjusted HR [aHR]: 0.82; 95% CI: 0.77-0.88; P < 0.01) and a higher rate of repeat procedures (aHR: 1.37; 95% CI: 1.32-1.43; P < 0.01). Patients undergoing surgical bypass at the highest quintile hospitals had a higher rate of major amputation (aHR: 1.21; 95% CI: 1.13-1.29; P < 0.01) and a lower rate of repeat procedures (aHR: 0.73; 95% CI: 0.70-0.76; P < 0.01).

CONCLUSIONS: This study showed large interhospital variability in revascularization strategies, as well as improved outcomes for patients receiving endovascular treatment at higher volume sites. Further work is needed to standardize treatments with the goal of improving limb salvage rates.

BACKGROUND: Ineligibility for surgical revascularization is increasingly prevalent and associated with increased mortality after percutaneous coronary intervention (PCI). High-quality, contemporary, multicenter data regarding clinical outcomes after PCI is scarce and poses a barrier to clinical decision-making for surgically ineligible patients. The aim of this study was to describe and compare the clinical characteristics, institutional variation, and longitudinal outcomes of PCI among surgically eligible and ineligible patients in the Veterans Affairs Healthcare System.

METHODS: Patients with left main and/or multivessel coronary artery disease undergoing index PCI between October 1, 2017 and September 30, 2022 were identified and the prevalence of surgical ineligibility determined by review of the electronic medical record. The association between surgical ineligibility and mortality and major adverse cardiovascular events (MACE; death, myocardial infarction, repeat revascularization, and stroke) was assessed.

RESULTS: A total of 6192 patients with left main and/or multivessel coronary artery disease (842 surgically ineligible and 5350 surgically eligible) underwent PCI during the study period. After adjustment, surgical ineligibility was associated with a significantly decreased time to mortality (time ratio, 0.801 [95% CI, 0.662-0.970]) over a median 1045-day (interquartile range, 583-1600) follow-up period, though not associated with composite MACE (time ratio, 0.859 [95% CI, 0.685-1.078]). After adjustment for target lesion characteristics and procedural complexity, the association between surgical ineligibility and mortality was attenuated (time ratio, 0.842 [95% CI, 0.688-1.030]).

CONCLUSIONS: Ineligibility for surgical revascularization was associated with increased risk of long-term mortality after PCI. The risk of adverse outcomes after PCI, however, was similar among surgically eligible and ineligible patients after adjusting for measured comorbidities, coronary anatomic features, and procedural complexity.

BACKGROUND: There may be variability in willingness to perform percutaneous coronary intervention (PCI) in higher-risk patients who present with ST-segment-elevation myocardial infarction (STEMI). We sought to describe current treatment selection patterns and hospital-level variability.

METHODS AND RESULTS: We identified patients presenting with STEMI with a culprit lesion on coronary angiography between January 1, 2019, and March 31, 2023, using the NCDR (National Cardiovascular Data Registry) CPMI (Chest Pain-Myocardial Infarction) registry. We compared patient-level characteristics of patients who did and did not undergo PCI at each hospital. There were 178 984 patients from 582 US hospitals presenting with STEMI who were included. Among patients with STEMI and a culprit lesion, 6180 did not undergo PCI (3.5%). Patients with a presentation of STEMI and a culprit lesion who did not undergo PCI were older (67 [interquartile range, 58-76]) years versus 62 ([interquartile range, 54-71] years, P<0.001), more likely to present with heart failure (15.0% versus 7.4%, P<0.001), and more likely to have cardiac arrest before arrival (9.7% versus 5.1%, P<0.001) than patients who underwent PCI. Patients who did not undergo PCI had higher predicted mortality rates (12.5%±17.9% versus 6.5%±11.5%, P<0.001) and observed mortality rates (21.7% versus 6.4%, P<0.001) compared with patients who underwent PCI.

CONCLUSIONS: There is variability in the percentage of patients with culprit lesions on invasive coronary angiography undergoing PCI for STEMI, with 3.5% of patients with STEMI not receiving PCI overall, and >5% of patients not undergoing PCI in a quarter of US hospitals. Differences in observed versus predicted mortality rates for patients who did or did not undergo PCI may highlight the effects of risk-avoidant behavior.

BACKGROUND: Catheter ablation is an effective therapy for ventricular tachycardia (VT) and is increasing in use. Assessment of contemporary real-world outcomes of VT ablation requires data inclusive of both inpatient and outpatient encounters.

OBJECTIVE: We aimed to assess factors associated with 1-year in-hospital mortality, all-cause readmission, and recurrent readmission for VT after VT ablation along with the associated costs of care.

METHODS: Inpatient and outpatient VT ablations were captured in the Healthcare Cost and Utilization Project data in Florida, Maryland, and New York from 2016 to 2020 with 1-year follow-up through 2021. Cox proportional hazards regression was used to identify risk factors associated with 1-year in-hospital mortality, all-cause readmission, and recurrent VT readmission. Costs of inpatient cases and readmission were captured.

RESULTS: Of 3899 patients undergoing VT ablation, 2% died during the initial episode of care. The 1-year in-hospital mortality rate, all-cause readmission rate, and recurrent VT readmission rate were 6.8%, 43.4%, and 16.9%, respectively, and were broadly stable during the study period. Coronary artery disease, chronic kidney disease, and heart failure were independently associated with an increased risk of in-hospital mortality and all-cause readmission within 1 year (P < .05). Recurrent VT was the most common cause of readmission. All-cause readmissions increased costs by 55%.

CONCLUSION: Mortality, long-term readmission, and recurrent VT remain high after VT ablation and include measurably important costs. Strategies to improve freedom from recurrent VT while managing comorbid conditions may serve as targets for improving the efficacy and cost-effectiveness of an important procedure applied to a vulnerable population.

BACKGROUND: Although Medicare Advantage (MA) plans provide coverage to >50% of Medicare beneficiaries, it is unclear whether MA claims can be used similarly to Medicare Fee-For-Service (FFS) claims for clinical outcomes assessment. In this study, we evaluate the accuracy of claims algorithms previously validated in FFS to assess comorbidities and outcomes in MA patients after aortic valve replacement.

METHODS: We compared the concordance of 11 claims-based covariates (diabetes, hypertension, atrial flutter/fibrillation, myocardial infarction) and outcomes (stroke, disabling stroke, transient ischemic attack, major vascular complication, bleeding, permanent pacemaker implantation, death) among FFS and MA patients with the covariates and adjudicated outcomes in the multinational Evolut Low-Risk Trial (2016-2018). We used claims algorithms for 1-year outcomes and calculated sensitivity, specificity, positive predictive value, negative predictive value, and kappa, using adjudicated outcomes as the reference. We compared the kappa for MA versus FFS using the 2-sample z-test with a significance level of P<0.05.

RESULTS: Among 1139 US patients aged 65+ years old in the Evolut Low-Risk Trial, 782 patients (175 MA and 607 FFS) were linked to claims data and had complete comorbidity data. Among all covariates, claims algorithms for covariates had sensitivities ≥85% for identifying diabetes, atrial flutter/fibrillation, and hypertension in MA and FFS. For the outcomes, sensitivities were ≥85% for bleeding (comprehensive), permanent pacemaker implantation, and death. The kappa was higher in MA versus FFS for diabetes (P=0.03) and hypertension (P=0.025) but was lower in myocardial infarction (P<0.0001). There was no statistically significant difference in the kappa agreement between MA versus FFS for any of the selected outcomes.

CONCLUSIONS: Medicare claims have a similar level of kappa agreement in MA versus FFS for most covariates and outcomes. As patients shift to MA, ascertainment of outcomes using Medicare claims in postapproval studies remains valid for select outcomes.