Publications

2019

Chung M, Zhao Y, Strom JB, Shen C, Yeh RW. Extracorporeal Membrane Oxygenation Use in Cardiogenic Shock: Impact of Age on In-Hospital Mortality, Length of Stay, and Costs.. Critical care medicine. 2019;47(3):e214-e221. doi:10.1097/CCM.0000000000003631

OBJECTIVES: Increasing age is a well-recognized risk factor for in-hospital mortality in patients receiving extracorporeal membrane oxygenation for cardiogenic shock, but the shape of this relationship is unknown. In addition, the impact of age on hospital length of stay, patterns of patient disposition, and costs has been incompletely characterized.

DESIGN: Retrospective analysis of the National Inpatient Sample.

SETTING: U.S. nonfederal hospitals, years 2004-2016.

PATIENTS: Adults with cardiogenic shock treated with extracorporeal membrane oxygenation (3,094; weighted national estimate: 15,415).

INTERVENTIONS: None.

MEASUREMENTS AND MAIN RESULTS: The mean age of extracorporeal membrane oxygenation recipients was 54.8 ± 15.4 years (range, 18-90 yr). Crude in-hospital mortality was 57.7%. Median time-to-death was 8 days (interquartile range, 3-17 d). A linear relationship between age and in-hospital mortality was observed with a 14% increase in the adjusted odds of in-hospital mortality for every 10-year increase in age (adjusted odds ratio, 1.14; 95% CI, 1.08-1.21; p < 0.0001). Thirty-four percent of patients were discharged alive at a median time of 30 days (interquartile range, 19-48 d). The median length of stay and total hospitalization costs were 14 days (interquartile range, [5-29 d]) and $134,573 ($71,782-$239,439), respectively, both of which differed significantly by age group (length of stay range from 17 d [18-49 yr] to 9 d [80-90 yr]; p < 0.0001 and cost range $147,548 [18-49 yr] to $105,350 [80-90 yr]; p < 0.0001).

CONCLUSIONS: Age is linearly associated with increasing in-hospital mortality in individuals receiving extracorporeal membrane oxygenation for cardiogenic shock without evidence of a threshold effect. Median time-to-death is approximately 1 week. One third of patients are discharged from the hospital alive, but the median time-to-discharge is 1 month. Median length of stay ranges from 9 to 17 days depending on age. Hospitalization costs exceed $100,000 in all age groups.

Kundi H, Popma JJ, Cohen DJ, et al. Prevalence and Outcomes of Isolated Tricuspid Valve Surgery Among Medicare Beneficiaries.. The American journal of cardiology. 2019;123(1):132-138. doi:10.1016/j.amjcard.2018.09.016

We sought to characterize the clinical outcomes and to identify predictors of mortality undergoing isolated tricuspid valve surgery in the United States. We identified 5,164 patients undergoing isolated tricuspid valve surgery from the Centers for Medicare and Medicaid Services Medicare Provider Analysis and Review data between January 2003 and December 2014. The primary outcome was all cause 1-year mortality. A backward elimination method was performed to identify predictors of 1-year mortality. Tricuspid valve repair was performed in 2,494 (48.3%) patients and tricuspid valve replacement was performed in 2,670 (51.7%) patients. Perioperative and 1-year mortality rates were 9.9% and 24.1%, respectively. Predictors of 1-year mortality were age (p <0.001), chronic heart failure (p = 0.001, cirrhosis (p <0.001), carcinoid syndrome (p <0.001), chronic kidney disease (p = 0.001), secondary pulmonary hypertension (p = 0.023), endocarditis (p = 0.005), decubitus ulcer (p <0.001), malnutrition (p <0.001), replacement (p = 0.013), emergency procedure (p <0.001), and preprocedural shock (p <0.001). The C-statistic for 1-year mortality was 0.70 (95% confidence interval, 0.67 to 0.73). In conclusion, isolated tricuspid valve surgery is infrequently performed in the United States, and is associated with high 1-year mortality. Patients at higher risk for mortality can be identified based on the presence of a number of comorbidities at the time of surgery.

Ferro EG, Secemsky EA, Wadhera RK, et al. Patient Readmission Rates For All Insurance Types After Implementation Of The Hospital Readmissions Reduction Program.. Health affairs (Project Hope). 2019;38(4):585-593. doi:10.1377/hlthaff.2018.05412

Since the implementation of the Hospital Readmissions Reduction Program (HRRP), readmissions have declined for Medicare patients with conditions targeted by the policy (acute myocardial infarction, heart failure, and pneumonia). To understand whether HRRP implementation was associated with a readmission decline for patients across all insurance types (Medicare, Medicaid, and private), we conducted a difference-in-differences analysis using information from the Nationwide Readmissions Database. We compared how quarterly readmissions for target conditions changed before (2010-12) and after (2012-14) HRRP implementation, using nontarget conditions as the control. Our results demonstrate that readmissions declined at a significantly faster rate after HRRP implementation not just for Medicare patients but also for those with Medicaid, both in the aggregate and for individual target conditions. However, composite Medicaid readmission rates remained higher than those for Medicare. Throughout the study period privately insured patients had the lowest aggregate readmission rates, which declined at a similar rate compared to nontarget conditions. The HRRP was associated with nationwide readmission reductions beyond the Medicare patients originally targeted by the policy. Further research is needed to understand the specific mechanisms by which hospitals have achieved reductions in readmissions.

Kundi H, Popma JJ, Reynolds MR, et al. Frailty and related outcomes in patients undergoing transcatheter valve therapies in a nationwide cohort.. European heart journal. 2019;40(27):2231-2239. doi:10.1093/eurheartj/ehz187

AIMS: We sought to identify the prevalence and related outcomes of frail individuals undergoing transcatheter mitral valve repair and transcatheter aortic valve replacement (TAVR).

METHODS AND RESULTS: Patients aged 65 and older were included in the study if they had at least one procedural code for transcatheter mitral valve repair or TAVR between 1 January 2016 and 31 December 2016 in the Centers for Medicare and Medicaid Services Medicare Provider and Review database. The Hospital Frailty Risk Score, an International Classification of Diseases, Tenth Revision (ICD-10) claims-based score, was used to identify frailty and the primary outcome was all-cause 1-year mortality. A total of 3746 (11.6%) patients underwent transcatheter mitral valve repair and 28 531 (88.4%) underwent TAVR. In the transcatheter mitral valve repair and TAVR populations, respectively, there were 1903 (50.8%) and 14 938 (52.4%) patients defined as low risk for frailty (score <5), 1476 (39.4%) and 11 268 (39.5%) defined as intermediate risk (score 5-15), and 367 (9.8%) and 2325 (8.1%) defined as high risk (score >15). One-year mortality was 12.8% in low-risk patients, 29.7% in intermediate-risk patients, and 40.9% in high-risk patients undergoing transcatheter mitral valve repair (log rank P < 0.001). In patients undergoing TAVR, 1-year mortality rates were 7.6% in low-risk patients, 17.6% in intermediate-risk patients, and 30.1% in high-risk patients (log rank P < 0.001).

CONCLUSIONS: This study successfully identified individuals at greater risk of short- and long-term mortality after undergoing transcatheter valve therapies in an elderly population in the USA using the ICD-10 claims-based Hospital Frailty Risk Score.

BACKGROUND: Randomized controlled trials are the "gold standard" for comparing the safety and efficacy of therapies but may be limited due to high costs, lack of feasibility, and difficulty enrolling "real-world" patient populations. The Extending Trial-Based Evaluations of Medical Therapies Using Novel Sources of Data (EXTEND) Study seeks to evaluate whether data collected within procedural registries and claims databases can reproduce trial results by substituting surrogate non-trial-based variables for exposures and outcomes.

METHODS AND RESULTS: Patient-level data from 2 clinical trial programs-the Dual Antiplatelet Therapy Study and the United States CoreValve Studies-will be linked to a combination of national registry, administrative claims, and health system data. The concordance between baseline and outcomes data collected within nontrial data sets and trial information, including adjudicated end point events, will be assessed. We will compare the study results obtained using these alternative data sources to those derived using trial-ascertained variables and end points using trial-adjudicated end points and covariates.

CONCLUSIONS: Linkage of trials to registries and claims data represents an opportunity to use alternative data sources in place of and as adjuncts to randomized clinical trial data but requires further validation. The results of this research will help determine how these data sources can be used to improve our present and future understanding of new medical treatments.

Kundi H, Wadhera RK, Strom JB, et al. Association of Frailty With 30-Day Outcomes for Acute Myocardial Infarction, Heart Failure, and Pneumonia Among Elderly Adults.. JAMA cardiology. 2019;4(11):1084-1091. doi:10.1001/jamacardio.2019.3511

IMPORTANCE: The addition of a claims-based frailty metric to traditional comorbidity-based risk-adjustment models for acute myocardial infarction (AMI), heart failure (HF), and pneumonia improves the prediction of 30-day mortality and readmission. This may have important implications for hospitals that tend to care for frail populations and participate in Centers for Medicare & Medicaid Services value-based payment programs, which use these risk-adjusted metrics to determine reimbursement.

OBJECTIVE: To determine whether the addition of frailty measures to traditional comorbidity-based risk-adjustment models improved prediction of outcomes for patients with AMI, HF, and pneumonia.

DESIGN, SETTING, AND PARTICIPANTS: A nationwide cohort study included Medicare fee-for-service beneficiaries 65 years and older in the United States between January 1 and December 1, 2016. Analysis began August 2018.

MAIN OUTCOMES AND MEASURES: Rates of mortality within 30 days of admission and 30 days of discharge, as well as 30-day readmission rates by frailty group. We evaluated the incremental effect of adding the Hospital Frailty Risk Score (HFRS) to current comorbidity-based risk-adjustment models for 30-day outcomes across all conditions.

RESULTS: For 785 127 participants, there were 166 200 hospitalizations [21.2%] for AMI, 348 619 [44.4%] for HF, and 270 308 [34.4%] for pneumonia. The mean (SD) age at the time of hospitalization was 79.2 (8.9) years; 656 315 (83.6%) were white and 402 639 (51.3%) were women. The mean (SD) HFRS was 7.3 (7.4) for patients with AMI, 10.8 (8.3) for patients with HF, and 8.2 (5.7) for patients with pneumonia. Among patients hospitalized for AMI, an HFRS more than 15 (compared with an HFRS <5) was associated with a higher risk of 30-day postadmission mortality (adjusted odds ratio [aOR], 3.6; 95% CI, 3.4-3.8), 30-day postdischarge mortality (aOR, 4.0; 95% CI, 3.7-4.3), and 30-day readmission (aOR, 3.0; 95% CI, 2.9-3.1) after multivariable adjustment for age, sex, race, and comorbidities. Similar patterns were observed for patients hospitalized with HF (30-day postadmission mortality: aOR, 3.5; 95% CI, 3.4-3.7; 30-day postdischarge mortality: aOR, 3.5; 95% CI, 3.3-3.6; and 30-day readmission: aOR, 2.9; 95% CI, 2.8-3.0) and among patients with pneumonia (30-day postadmission mortality: aOR, 2.5; 95% CI, 2.3-2.6; 30-day postdischarge mortality: aOR, 3.0; 95% CI, 2.9-3.2; and 30-day readmission: aOR, 2.8; 95% CI, 2.7-2.9). The addition of HFRS to traditional comorbidity-based risk-prediction models improved discrimination to predict outcomes for all 3 conditions.

CONCLUSIONS AND RELEVANCE: Among Medicare fee-for-service beneficiaries, frailty as measured by the HFRS was associated with mortality and readmissions among patients hospitalized for AMI, HF, or pneumonia. The addition of HFRS to traditional comorbidity-based risk-prediction models improved the prediction of outcomes for all 3 conditions.

Kiefer NJ, Salber GC, Burke GM, et al. The Impact of Basal Septal Hypertrophy on Outcomes after Transcatheter Aortic Valve Replacement.. Journal of the American Society of Echocardiography : official publication of the American Society of Echocardiography. 2019;32(11):1416-1425. doi:10.1016/j.echo.2019.06.012

BACKGROUND: The role of basal septal hypertrophy (BSH) on preprocedural transthoracic echocardiography in transcatheter aortic valve replacement (TAVR) is unknown.

METHODS: Medical charts and preprocedural transthoracic echocardiograms of 378 patients who underwent TAVR were examined. The association between BSH and the primary composite outcome of valve pop-out, recapture, embolization, aborted procedure, conversion to open procedure, new conduction disturbance, or need for permanent pacemaker ≤30 days after TAVR was evaluated. Patients with preexisting pacemakers were excluded. Sensitivity analyses were performed varying the definition of BSH.

RESULTS: Of 296 TAVR patients (78.3%) with interpretable images, 55 (18.6%) had BSH at a median of 40 days (interquartile range, 19-62 days) before TAVR. Age and sex were similar among those with and without BSH. BSH patients received postdilation more frequently (BSH+ vs BSH-: 41.8% vs 29.9%, P = .04). A total of 50 individuals (16.9%) received pacemakers within 30 days, and 128 (43.2%) developed conduction disturbances (with left bundle branch block most common), without differences between groups. BSH was unrelated to the primary outcome on multivariate analysis (adjusted odds ratio BSH+ vs BSH-, 0.94; 95% CI, 0.42-2.11; P = .88).

CONCLUSIONS: In this convenience sample of TAVR recipients at a large academic medical center, patients with BSH were more likely to receive postdilation. BSH was not associated with procedural or conduction outcomes after TAVR in patients without preexisting pacemakers.

Strom JB, Zhao Y, Faridi KF, et al. Comparison of Clinical Trials and Administrative Claims to Identify Stroke Among Patients Undergoing Aortic Valve Replacement: Findings From the EXTEND Study.. Circulation. Cardiovascular interventions. 2019;12(11):e008231. doi:10.1161/CIRCINTERVENTIONS.119.008231

BACKGROUND: Cerebrovascular events (CVEs) are devastating complications after aortic valve replacement. We assessed whether billing claims accurately identify CVEs in place of clinical event adjudication in structural heart disease trials.

METHODS: Adult participants in the US CoreValve High Risk and SURTAVI trials (Surgical or Transcatheter Aortic-Valve Replacement in Intermediate-Risk Patients) were linked to Medicare inpatient claims from January 1, 2006 to December 31, 2016. Claims consistent with CVEs within 14 days of a similar trial-adjudicated CVE were considered a match. The sensitivity, specificity, and positive and negative predictive values of International Classification of Diseases,Ninth andTenthRevisions, Clinical Modification billing codes for cerebrovascular disease were determined against trial-defined CVEs as the criterion standard. Kaplan-Meier estimates of claims-defined versus trial-defined CVEs were compared.

RESULTS: Among 4230 linked trial participants (linkage rate 79.8%), 550 (13.0%) sustained 630 adjudicated CVEs over a 5-year follow-up period. Linked and nonlinked individuals were similar. An algorithm using 4 International Classification of Diseases, Ninth Revision, Clinical Modification codes (434.91, 434.11, 433.11, and 997.02) had a sensitivity of 60.9%, specificity of 99.0%, positive predictive value of 86.5%, and negative predictive value of 95.8% for identifying a trial-adjudicated ischemic stroke. An algorithm using 3 International Classification of Diseases, Tenth Revision, Clinical Modification codes (I63.9, I63.40, I63.49) had a sensitivity of 66.7%, specificity of 99.4%, positive predictive value of 88.9%, and negative predictive value of 97.6%.

CONCLUSIONS: In linked clinical trial and Medicare claims data, 4 International Classification of Diseases, Ninth Revision, Clinical Modification and 3 International Classification of Diseases, Tenth Revision, Clinical Modification billing codes identified half of trial-adjudicated CVEs during follow-up with high specificity and predictive value, but imperfect sensitivity. Although low sensitivity may limit the use of claims to substitute for traditional trial outcomes to identify CVEs, high specificity suggests claims could be used to trigger evaluation of neurological events, potentially improving the efficiency of the evaluation of techniques and devices designed to reduce such events.