The Association Between the Use of Low-Slice Computed Tomography Machines and Downstream Care: Comparative Study of 16-Slice and 64-Slice Computed Tomography Angiography.

BACKGROUND: Although computed tomography (CT) studies on machines with more slices have reported higher positive and negative predictive values, the impact of using low-slice (16-slice) CT machines on downstream testing has not been well studied. In community outpatient settings, low-slice CT machines remain in use, although many hospitals have adopted higher-slice machines. OBJECTIVE: This study examines the association between the use of low-slice CT machines and downstream invasive testing in the context of the CT angiography of the neck. METHODS: Included health insurance claims pertained to adults with commercial or Medicare Advantage health plans who underwent the CT angiography of the neck. Site certification data were used to assign counts of slices to claims. Claims that were made in the 60 days after CT were examined for cervicocerebral angiography. The association between the number of slices and cervicocerebral angiography was evaluated by using a chi-square test and multivariate logistic regression. RESULTS: Claims for 16-slice CT had a 5.1% (33/641) downstream cervicocerebral angiography rate, while claims for 64-slice CT had a 3.1% (35/1125) rate, and a significant difference (P=.03) was observed. An analysis that was adjusted for patient demographics also found a significant relationship (odds ratio 1.64, 95% CI 1.00-2.69; P=.047). CONCLUSIONS: The use of low-slice CT machines in the community may impact the quality of care and result in more downstream testing.

The association between provider characteristics and post-catheterization interventions.

OBJECTIVES: To examine whether the demographics of providers' prior year patient cohorts, providers' historic degree of catheter-based fractional flow reserve (FFR) utilization, and other provider characteristics were associated with post-catheterization performance of percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG). STUDY DESIGN: A retrospective, observational analysis of outpatient claims data was performed. METHODS: All 2018 outpatient catheterization claims from a national organization offering commercial and Medicare Advantage health plans were examined. Claims were excluded if the patient had a prior catheterization in 2018, had any indications of CABG or valvular heart disease in the prior year of claims, or if the provider had ≤10 catheterization claims in 2017. Downstream PCI and CABG were determined by examining claims 0-30 days post-catheterization. Using multivariate mixed effects logistic regression with provider identity random effects, the association between post-catheterization procedures and provider characteristics was assessed, controlling for patient characteristics. RESULTS: The sample consisted of 31,920 catheterization claims pertaining to procedures performed by 964 providers. Among the catheterization claims, 8,554 (26.8%) were followed by PCI and 1,779 (5.6%) were followed by CABG. Catheterizations performed by providers with older prior year patient cohorts were associated with higher adjusted odds of PCI (1.78; CI: 1.26-2.53), even after controlling for patient age. Catheterizations performed by providers with greater historic use of FFR had significantly higher adjusted odds of being followed by PCI (1.73; CI: 1.26-2.37). CONCLUSION: Provider characteristics may impact whether patients receive a procedure post-catheterization. Further research is needed to characterize this relationship.

A Description of Outcomes Experienced by Patients Whose Orders for Peripheral Artery Revascularization Were Reviewed by a Nondenial Prior Authorization Program.

OBJECTIVE: After a nondenial prior authorization program evaluates orders for peripheral artery revascularization (PAR), ordering physicians sometimes withdraw their orders based upon program recommendations. Some patients with withdrawn orders receive PAR if claudication does not resolve. To characterize patient outcomes under this program, we evaluated whether associations existed between the withdrawal of patients' initial PAR orders and the presence of claims for PAR and claims mentioning intermittent claudication (IC) in the following 16 weeks. METHODS: Orders for PAR placed from 1/1/19 to 9/30/19 for patients with Medicare Advantage health plans were extracted from a national healthcare organization's database. Claims data from 0 to 16 weeks following the order were reviewed to determine if patients had downstream PAR claims, or if they had emergency department or hospital claims mentioning IC. Chi-square tests were used to assess the association between order withdrawal and downstream PAR, as well as claims mentioning IC. Multivariate logistic regressions were run to assess the same, controlling for patient age, sex, urbanicity, local median income, state obesity rate, type of PAR, ordering physician specialty, and whether PAR was ordered in a hospital setting. RESULTS: Of 1588 orders meeting inclusion criteria, 71.9% (1038/1444) of authorized orders and 61.1% (88/144) of withdrawn orders were followed by PAR within 16 weeks, a significant difference (P < .01). Relatedly, 69.8% (1008/1444) of authorized orders and 70.8% (102/144) of withdrawn orders were followed by IC claims, an insignificant difference. Multivariate logistic regressions showed patients with withdrawn PAR orders had significantly lower adjusted odds of PAR (OR: 0.63; 95% CI: 0.44-0.91), but an insignificant difference in their adjusted odds of IC (OR: 1.10; CI: 0.76-1.64). CONCLUSIONS: Although patients with withdrawn PAR orders were significantly less likely to receive PAR in the subsequent 16 weeks, no association was found between withdrawn PAR orders and subsequent claims mentioning IC.

Characterizing Cardiac Catheterization Utilization in a US Population with Commercial or Medicare Advantage Health Plans.

Background: Health plans and health systems need to understand the demand for common healthcare services to ensure adequate access to care. Utilization of cardiac catheterization is of particular interest, because it is relatively common and has the potential for variation across subpopulations, similar to the level of geographical variation in heart disease in the United States. Objectives: To illustrate how the utilization of cardiac catheterization has changed over time in a US population with commercial and Medicare Advantage health plans, and how it differs between subpopulations. Methods: Cardiac catheterization claims data from 2012 to 2018 were extracted from the database of a national healthcare organization offering commercial and Medicare Advantage health plans. Contemporaneous health plan enrollment data and government data were used to determine the patients' characteristics. Annual catheterizations per 1000 patients for the population as a whole and for subpopulations were determined using claims data. Spearman's rank-order correlation was used to assess the monotonicity of trends. Catheterization utilization for each subpopulation was compared with that of the population average. A second, patient-level analysis was used to determine the factors predictive of patients' catheterization utilization in 2018. Results: Across the overall population, the rate of cardiac catheterization was stable from 2012 to 2018. An adjusted analysis of 2018 data showed that catheterization utilization was significantly associated with older age, male sex, residence in a rural zip code, residence in a lower-income zip code, and residence in a state with a high obesity rate. The trendlines of the relative utilization of catheterization in subpopulations over time revealed similar patterns. Conclusion: Marked differences were observed in the rates of cardiac catheterization utilization between the subpopulations in our study. Overall, these data show a direct correlation between geographic residence, obesity level, wealth, and the rate of cardiac catheterization utilization. To ensure adequate access to care, health plans and health systems should explore the implications of disproportionately high demand for cardiac catheterization in populations from lower-income areas, higher obesity rate states, rural patients, and older patients.

Determinants of outcomes following outpatient placement of implantable cardioverter defibrillators in a Medicare Advantage population.

BACKGROUND: Recipients of ICD are likely to have several risk factors that could interfere with successful use of implantable cardioverter defibrillators (ICDs). HYPOTHESIS: Age, sex, and factors indicated in claims are associated with one-year mortality and complications after ICD placement. METHODS: Adult Medicare Advantage patients who underwent outpatient ICD implantation from January 2014 to September 2015 were included. Age, sex, Charlson Comorbidity Index (CCI), prior year hospitalization and emergency department (ED) visit, diabetes, heart failure, ischemic heart disease, and indicators of the need for pacing were evaluated as risk factors. Mortality and device-related complications (lead and nonlead) were assessed at one-year post-procedure using Kaplan-Meier and Cox Proportional Hazard analysis. RESULTS: Among 8450 patients who underwent implantation, 1-year event-free survival was 80.1%, based on an overall composite measure of complications and mortality. Adjusted survival analysis showed that age ≥ 65, male sex, incremental increase in CCI, heart failure, prior year hospitalization, ED visit, and prior year pacing procedure were significant predictors of mortality. Age ≥ 65, male sex, and prior year hospitalization were significant predictors of a composite measure of device-related complications. CCI and prior hospitalization were significant predictors of a composite measure of any adverse outcome. CONCLUSIONS: Results suggest most patients in an older population do not experience adverse outcomes in the year following ICD implantation. The risk of mortality may be greater in men, patients over the age of 65, and patients with greater general morbidity, heart failure, or a history of a pacing procedure.

An exploration of the association between ischemic etiology and the likelihood of heart failure hospitalization following cardiac resynchronization therapy.

BACKGROUND: Myocardial scarring resulting from cardiomyopathy with ischemic etiology may interfere with effective lead placement during implantation of multi-lead cardioverter-defibrillators for cardiac resynchronization therapy (CRT-D). Extensive scarring is known to be associated with poorer physiological and survival outcomes in patients who undergo CRT-D. HYPOTHESIS: Ischemic CRT-D recipients respond as well as nonischemic recipients, using hospital admission for heart failure (HF) as a measure of response. METHODS: Patients who underwent CRT-D between February 1, 2013, and February 1, 2014, were identified in an insurer's claims. Inclusion required 1 year of enrollment pre- and post-CRT-D. The sample was divided into nonischemic and ischemic groups, and a subset of the ischemic group with a history of ST-segment elevation myocardial infarction (STEMI) was identified. The likelihood of HF hospital admissions in the year before and after CRT-D was computed for each group, as well as for the subset of patients with HF admissions prior to CRT-D. RESULTS: A significant (P = 0.02) association was found between ischemic etiology and the post-CRT-D HF admission likelihood. No association was found between history of STEMI vs nonischemic status and likelihood of post-CRT-D HF admission. All groups had significantly lower risk of HF admissions after CRT-D. None of the comparisons involving only patients with a HF hospitalization in the year prior to CRT-D were significant. CONCLUSIONS: Patients with nonischemic etiology were significantly less likely to experience a HF admission after CRT-D, but the risk of HF admission improved significantly in all groups after CRT-D.

Recording undetected P waves in a case of heart transplant with a new bipolar system.

Using a new electrocardiographic lead (L-P lead), we recorded undetected P waves in a post heart-transplant patient. This case shows another application of a noninvasive method, a modification of Einthoven's bipolar leads, used to approach undetermined rhythms.