Estimation of DAPT Study Treatment Effects in Contemporary Clinical Practice: Findings From the EXTEND-DAPT Study.

BACKGROUND: Differences in patient characteristics, changes in treatment algorithms, and advances in medical technology could each influence the applicability of older randomized trial results to contemporary clinical practice. The DAPT Study (Dual Antiplatelet Therapy) found that longer-duration DAPT decreased ischemic events at the expense of greater bleeding, but subsequent evolution in stent technology and clinical practice may attenuate the benefit of prolonged DAPT in a contemporary population. We evaluated whether the DAPT Study population is different from a contemporary population of US patients receiving percutaneous coronary intervention and estimated the treatment effect of extended-duration antiplatelet therapy after percutaneous coronary intervention in this more contemporary cohort. METHODS: We compared the characteristics of drug-eluting stent-treated patients randomly assigned in the DAPT Study to a sample of more contemporary drug-eluting stent-treated patients in the National Cardiovascular Data Registry CathPCI Registry from July 2016 to June 2017. After linking trial and registry data, we used inverse-odds of trial participation weighting to account for patient and procedural characteristics and estimated a contemporary real-world treatment effect of 30 versus 12 months of DAPT after coronary stent procedures. RESULTS: The US drug-eluting stent-treated trial cohort included 8864 DAPT Study patients, and the registry cohort included 568 540 patients. Compared with the trial population, registry patients had more comorbidities and were more likely to present with myocardial infarction and receive 2nd-generation drug-eluting stents. After reweighting trial results to represent the registry population, there was no longer a significant effect of prolonged DAPT on reducing stent thrombosis (reweighted treatment effect: -0.40 [95% CI, -0.99% to 0.15%]), major adverse cardiac and cerebrovascular events (reweighted treatment effect, -0.52 [95% CI, -2.62% to 1.03%]), or myocardial infarction (reweighted treatment effect, -0.97% [95% CI, -2.75% to 0.18%]), but the increase in bleeding with prolonged DAPT persisted (reweighted treatment effect, 2.42% [95% CI, 0.79% to 3.91%]). CONCLUSIONS: The differences between the patients and devices used in contemporary clinical practice compared with the DAPT Study were associated with the attenuation of benefits and greater harms attributable to prolonged DAPT duration. These findings limit the applicability of the average treatment effects from the DAPT Study in modern clinical practice.

Watchman device migration and embolization: A report from the NCDR LAAO Registry.

INTRODUCTION: Incomplete anchoring of the Watchman left atrial appendage closure (LAAO) device can result in substantial device migration or device embolization (DME) requiring percutaneous or surgical retrieval. METHODS: We performed a retrospective analysis of Watchman procedures (January 2016 through March 2021) reported to the National Cardiovascular Data Registry LAAO Registry. We excluded patients with prior LAAO interventions, no device released, and missing device information. In-hospital events were assessed among all patients and postdischarge events were assessed among patients with 45-day follow-up. RESULTS: Of 120 278 Watchman procedures, the in-hospital DME rate was 0.07% (n = 84) and surgery was commonly performed (n = 39). In-hospital mortality rate was 14% among patients with DME and 20.5% among patients who underwent surgery. In-hospital DME was more common: at hospitals with a lower median annual procedure volume (24 vs. 41 procedures, p < .0001), with Watchman 2.5 versus Watchman FLX devices (0.08% vs. 0.04%, p = .0048), with larger LAA ostia (median 23 vs. 21 mm, p = .004), and with a smaller difference between device and LAA ostial size (median difference 4 vs. 5 mm, p = .04). Of 98 147 patients with 45-day follow-up, postdischarge DME occurred in 0.06% (n = 54) patients and cardiac surgery was performed in 7.4% (n = 4) of cases. The 45-day mortality rate was 3.7% (n = 2) among patients with postdischarge DME. Postdischarge DME was more common among men (79.7% of events but 58.9% of all procedures, p = .0019), taller patients (177.9 vs. 172 cm, p = .0005), and those with greater body mass (99.9 vs. 85.5 kg, p = .0055). The rhythm at implant was less frequently AF among patients with DME compared to those without (38.9% vs. 46.9%, p = .0098). CONCLUSION: While Watchman DME is rare, it is associated with high mortality and frequently requires surgical retrieval, and a substantial proportion of events occur after discharge. Due to the severity of DME events, risk mitigation strategies and on-site cardiac surgical back-up are of paramount importance.

In-hospital complications associated with pulmonary vein isolation with adjunctive lesions: the NCDR AFib Ablation Registry.

AIMS: No prior study has been adequately powered to evaluate real-world safety outcomes in those receiving adjunctive ablation lesions beyond pulmonary vein isolation (PVI). We sought to evaluate characteristics and in-hospital complications among patients undergoing PVI with and without adjunctive lesions. METHODS AND RESULTS: Patients in the National Cardiovascular Data Registry AFib Ablation Registry undergoing first-time atrial fibrillation (AF) ablation between 2016 and 2020 were identified and stratified into paroxysmal (PAF) and persistent AF, and separated into PVI only, PVI + cavotricuspid isthmus (CTI) ablation, and PVI + adjunctive (superior vena cava isolation, coronary sinus, vein of Marshall, atypical atrial flutter lines, other). Adjusted odds of adverse events were calculated using multivariable logistic regression. A total of 50 937 patients [PAF: 30 551 (60%), persistent AF: 20 386 (40%)] were included. Among those with PAF, there were no differences in the adjusted odds of complications between PVI + CTI or PVI + adjunctive when compared with PVI only. Among persistent AF, PVI + adjunctive was associated with a higher risk of any complication [3.0 vs. 4.5%, odds ratio (OR) 1.30, 95% confidence interval (CI) 1.07-1.58] and major complication (0.8 vs. 1.4%, OR 1.56, 95% CI 1.10-2.21), while no differences were observed in PVI + CTI compared with PVI only. Overall, there was high heterogeneity in adjunctive lesion type, and those receiving adjunctive lesions had a higher comorbidity burden. CONCLUSION: Additional CTI ablation was common without an increased risk of complications. Adjunctive lesions other than CTI are commonly performed in those with more comorbidities and were associated with an increased risk of complications in persistent AF, although the current analysis is limited by high heterogeneity in adjunctive lesion set type.

Abnormal left atrial body stiffness is predicted by appendage size: impact of appendage occlusion on left atrial mechanics assessed by pressure-volume analysis.

Atrial cardiomyopathy has been recognized as having important consequences for cardiac performance and clinical outcomes. The pathophysiological role of the left atrial (LA) appendage and the effect of percutaneous left atrial appendage occlusion (LAAO) upon LA mechanics is incompletely understood. We evaluated if changes in LA stiffness due to endocardial LAAO can be detected by LA pressure-volume (PV) analysis and whether stiffness parameters are associated with baseline characteristics. Patients undergoing percutaneous endocardial LAAO (n = 25) were studied using a novel PV analysis using near-simultaneous three-dimensional LA volume measurements by transesophageal echocardiography (TEE) and direct invasive LA pressure measurements. LA stiffness (dP/dV, change in pressure with change in volume) was calculated before and after LAAO. Overall LA stiffness significantly increased after LAAO compared with baseline (median, 0.41-0.64 mmHg/mL; P ≪ 0.001). LA body stiffness after LAAO correlated with baseline LA appendage size by indexed maximum depth (Spearman's rank correlation coefficient Rs = 0.61; P < 0.01). LA stiffness change showed an even stronger correlation with baseline LA appendage size by indexed maximum depth (Rs = 0.70; P < 0.001). We found that overall LA stiffness increases after endocardial LAAO. Baseline LA appendage size correlates with the magnitude of increase and LA body stiffness. These findings document alteration of LA mechanics after endocardial LAAO and suggest that the LA appendage modulates overall LA compliance.NEW & NOTEWORTHY Our study documents a correlation of LA appendage remodeling with the degree of chronically abnormal LA body stiffness. In addition, we found that LA appendage size was the baseline parameter that best correlated with the magnitude of a further increase in overall LA stiffness after appendage occlusion. These findings offer insights about the LA appendage and LA mechanics that are relevant to patients at risk for adverse atrial remodeling, especially candidates for LA appendage occlusion.

Risk and predictors of mortality after implantable cardioverter-defibrillator implantation in patients with sarcoid cardiomyopathy.

BACKGROUND: Implantable cardioverter-defibrillators (ICDs) are recommended for patients with cardiac sarcoidosis (CS) with an indication for pacing, prior ventricular arrhythmias, cardiac arrest, or left ventricular ejection fraction <35%, but data on outcomes are limited. METHODS: Using data from the National Cardiovascular Data Registry ICD Registry between April 1, 2010 and December 31, 2015, we evaluated a propensity matched cohort of CS patients implanted with ICDs versus non-ischemic cardiomyopathies (NICM). We compared mortality using Kaplan-Meier survival curves and Cox proportional hazards models. RESULTS: We identified 1,638 patients with CS and 8,190 propensity matched patients with NICM. The rate of death at 1 and 2 years was similar in patients with CS and patients with NICM (5.2% vs 5.4%, P = 0.75 and 9.0% vs 9.3%, P = 0.72, respectively). After adjusting for other covariates, patients with CS had similar mortality at 2 years after ICD implantations compared with NICM patients (RR 1.03, 95% CI 0.87-1.23). Among patients with CS, multivariable logistic regression identified 6 factors significantly associated with increased 2-year mortality: presence of heart failure (HR 1.92, 95% CI 1.44-3.22), New York Heart Association (NYHA) Class III heart failure (HR 1.68, 95% CI 1.16-2.45), NYHA Class IV heart failure (HR 3.08, 95% CI 1.49-6.39), atrial fibrillation/flutter (HR 1.66, 95% CI 1.17-2.35), chronic lung disease (HR 1.64, 95% CI 1.17-2.29), creatinine >2.0 mg/dL (HR 4.07, 95% CI 2.63-6.30), and paced rhythm (HR 2.66, 95% CI 1.07-6.59). CONCLUSION: Mortality following ICD implantation was similar in CS patients compared with propensity matched NICM patients. Presence of heart failure, NYHA class, atrial fibrillation/flutter, chronic lung disease, renal dysfunction, and paced rhythm at time of implantation were all predictors of increased 2-year mortality among CS patients with ICDs.

Development and validation of an automated algorithm for end point adjudication for a large U.S. national registry.

BACKGROUND: Clinical events committee (CEC) evaluation is the standard approach for end point adjudication in clinical trials. Due to resource constraints, large registries typically rely on site-reported end points without further confirmation, which may preclude use for regulatory oversight. METHODS: We developed a novel automated adjudication algorithm (AAA) for end point adjudication in the National Cardiovascular Data Registry Left Atrial Appendage Occlusion (LAAO) Registry using an iterative process using CEC adjudication as the "gold standard." A ≥80% agreement rate between automated algorithm adjudication and CEC adjudication was prespecified as clinically acceptable. Agreement rates were calculated. RESULTS: A total of 92 in-hospital and 127 post-discharge end points were evaluated between January 1, 2016 and June 30, 2019 using AAA and CEC. Agreement for neurologic events was >90%. Percent agreement for in-hospital and post-discharge events was as follows: ischemic stroke 95.7% and 94.5%, hemorrhagic stroke 97.8% and 96.1%, undetermined stroke 97.8% and 99.2%, transient ischemic attack 98.9% and 98.4% and intracranial hemorrhage 100.0% and 94.5%. Agreement was >80% for major bleeding (83.7% and 90.6%) and major vascular complication (89.1% and 97.6%). With this approach, <1% of site reported end points require CEC adjudication. Agreement remained very good during the period after algorithm derivation. CONCLUSIONS: An AAA-guided approach for end point adjudication was successfully developed and validated for the LAAO Registry. With this approach, the need for formal CEC adjudication was substantially reduced, with accuracy maintained above an 80% agreement threshold. After application specific validation, these methods could be applied to large registries and clinical trials to reduce the cost of event adjudication while preserving scientific validity.

Trends in ICD Implantations and in-Hospital Outcomes After DOJ Investigation.

BACKGROUND: The Department of Justice (DOJ) investigated implantable cardioverter-defibrillators (ICDs) not meeting the Centers for Medicare & Medicaid Services National Coverage Determination (NCD) criteria, resulting in increased adherence to the NCD criteria. Trends of the specific reasons for patients not meeting the NCD criteria and in-hospital outcomes for those patients are not known. METHODS AND RESULTS: We analyzed 300,151 primary-prevention ICDs from 2007-2015 at 1809 hospitals. We calculated the rates of in-hospital adverse events and the proportion of ICDs not meeting the 4 NCD criteria before and after the announcement of the DOJ investigation, stratified by whether hospitals paid settlements to the DOJ. Most reductions in the use of devices in patients not meeting NCD criteria were in patients with recently diagnosed heart failure (15.5%-6.8% for settled; 13.5%-7.3% for nonsettled) and who had had a recent myocardial infarction (8.4%-1.3% for settled; 7.4% to 1.5% for nonsettled). Adverse-event rates were significantly higher for ICDs not meeting NCD criteria (odds ratio 1.26 for settled; P < 0.001; 1.18 for nonsettled; P = 0.001). CONCLUSIONS: After the investigation, there was a rapid reduction in the placement of ICDs in patients with recent acute myocardial infarction or recent diagnosis of heart failure. Patients who did not meet NCD criteria experienced more in-hospital adverse events and higher mortality rates.

The Evolving Landscape of Impella Use in the United States Among Patients Undergoing Percutaneous Coronary Intervention With Mechanical Circulatory Support.

BACKGROUND: Impella was approved for mechanical circulatory support (MCS) in 2008, but large-scale, real-world data on its use are lacking. Our objective was to describe trends and variations in Impella use, clinical outcomes, and costs across US hospitals in patients undergoing percutaneous coronary intervention (PCI) treated with MCS (Impella or intra-aortic balloon pump). METHODS: From the Premier Healthcare Database, we analyzed 48 306 patients undergoing PCI with MCS at 432 hospitals between January 2004 and December 2016. Association analyses were performed at 3 levels: time period, hospital, and patient. Hierarchical models with propensity adjustment were used for association analyses. We examined trends and variations in the proportion of Impella use, and associated clinical outcomes (in-hospital mortality, bleeding requiring transfusion, acute kidney injury, stroke, length of stay, and hospital costs). RESULTS: Among patients undergoing PCI treated with MCS, 4782 (9.9%) received Impella; its use increased over time, reaching 31.9% of MCS in 2016. There was wide variation in Impella use across hospitals (>5-fold variation). Specifically, among patients receiving Impella, there was a wide variation in outcomes of bleeding (>2.5-fold variation), and death, acute kidney injury, and stroke (all ≈1.5-fold variation). Adverse outcomes and costs were higher in the Impella era (years 2008-2016) versus the pre-Impella era (years 2004-2007). Hospitals with higher Impella use had higher rates of adverse outcomes and costs. After adjustment for the propensity score, and accounting for clustering of patients by hospitals, Impella use was associated with death: odds ratio, 1.24 (95% CI, 1.13-1.36); bleeding: odds ratio, 1.10 (95% CI, 1.00-1.21); and stroke: odds ratio, 1.34 (95% CI, 1.18-1.53), although a similar, nonsignificant result was observed for acute kidney injury: odds ratio, 1.08 (95% CI, 1.00-1.17). CONCLUSIONS: Impella use is rapidly increasing among patients undergoing PCI treated with MCS, with marked variability in its use and associated outcomes. Although unmeasured confounding cannot be ruled out, when analyzed by time periods, or at the hospital level or the patient level, Impella use was associated with higher rates of adverse events and costs. More data are needed to define the appropriate role of MCS in patients undergoing PCI.

Impact of insurance status on ICD implantation practice patterns: Insights from the NCDR ICD registry.

BACKGROUND: Whether insurance status influences practice patterns in implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy (CRT) defibrillators, when indicated, is not known. METHODS AND RESULTS: We analyzed the NCDR ICD Registry to evaluate associations of insurance status with guidelines-based receipt of CRT, as well as device-type, complication rates, and use of optimal medical therapy defined by guidelines. Among 798,028 patients with de novo ICD implants, we included only patients < 65 years (those older have Medicare) and excluded those admitted before 2006 (n=1,835) or with insurance coverage other than Medicare, Medicaid or private insurance (n=25,695) leaving 286,556 for analysis. Inverse probability of treatment weighting was used to control for imbalances between groups. Mean age was 53 years, 29% were female. Patients with private insurance and Medicare were more likely to receive CRT-D when indicated (79.6%, OR 1.19 95% CI 1.09-1.28, P <.001 and 78.5%, OR 1.11 95% CI 1.01-1.21 P = .03, respectively) compared to the uninsured (76.7%). The uninsured were also more likely than other groups to receive a single-chamber device. Complication rates did not differ. Uninsured patients were, however, more likely to receive optimal medical therapy, particularly in the subgroup receiving the implant for primary prevention. CONCLUSIONS: In propensity-weighted analysis, uninsured patients are less likely to receive CRT when indicated but more likely to be receiving optimal medical therapy at discharge. Reasons for differences in device implantation practices based on insurance status require further study.

Paclitaxel-coated devices in the treatment of femoropopliteal stenosis among patients ≥65 years old: An ACC PVI Registry Analysis.

BACKGROUND: The connection between paclitaxel-coated devices (PCD) use during peripheral vascular interventions (PVI) and mortality is debated. We aimed to analyze patterns of PCD use and the safety and effectiveness of PCD use in the superficial femoral and/or popliteal arteries. METHODS: Patients undergoing PVI of femoropopliteal lesions with and without PCD between January 1, 2015 and June 30, 2017 were compared using the American College of Cardiology's National Cardiovascular Data Registry PVI Registry. Outcomes were derived from Centers for Medicare & Medicaid claims data. The primary outcome was all-cause mortality at 6-, 12-, and 24-months following PVI. Inverse probability weighting and frailty models were used to assess the differences between groups. The analysis was IRB-approved. RESULTS: In the overall cohort consisting of 6,302 femoropopliteal PVIs, PCD-PVI patients were more likely to be treated for claudication (63.5% vs 51.3%, P< .001), less likely to have a chronic total occlusion (24.6% vs 34.7%, P < .001), and more likely to be treated in certain geographic and practice settings. In the analytic cohort consisting of 1,666 femoropopliteal PVIs with linked claims outcomes (888 PCD-PVI, 53.3%), unadjusted rates of all outcomes were lower in PCD-PVI patients. After adjustment, there were no significant differences in mortality following PCD-PVI versus non-PCD PVI at 1 year (adjusted RR 0.78, 95% CI 0.60-1.01, P= .055) or 2 years (aRR 0.98, 95% CI 0.77-1.24, P= .844). CONCLUSION: There were significant differences between the patients in whom and settings in which PCD-PVI was versus was not used. PCD-PVI was not associated with an increased risk of 2-year mortality in real-world use.

Characteristics of cardiac catheterization laboratory directors at the 2017 U.S. News & World Report top 100 U.S. cardiovascular hospitals.

INTRODUCTION: The cardiac catheterization laboratory (CCL) is a focal point for cardiovascular programs and the CCL director represents the key personnel. We outline profiles of CCL directors at the 2017 U.S. News & World Report top 100 U.S. cardiovascular hospitals. METHODS: Using hospital websites, LinkedIn, Healthgrades, Medicare Provider Utilization and Payment Data 2017, and Scopus, we described CCL directors (in 2017) by age, gender, years since medical graduation, international medical school graduate (IMG) status, academic rank, provider clinical focus, and Hirsch (h)-index. RESULTS: Nearly all CCL directors were male (97%). The median age (interquartile range [IQR]) was 53 (49-61) years and median (IQR) years since medical school graduation was 28 (23-35) years. Over a third of CCL directors (39.4%) were IMGs and 38.4% had completed fellowship training at the same facility where they were CCL director. The median (IQR) h-index was 11 (6-22). Of the 69.7% CCL directors who held faculty positions, 60.9% were professors and 30.4% were associate professors. From Medicare data, 45.5% performed only percutaneous coronary interventions, 41.4% performed structural interventions, 3.0% peripheral interventions, and 2.0% performed both structural and peripheral. CCL directors at the top 25 hospitals had higher h-indexes, and more likely to have completed fellowship training at their own institution. CONCLUSIONS: There are very few women CCL directors at the top U.S. cardiovascular hospitals. A third of the CCL directors were IMGs. A significant proportion of CCL directors primarily performed structural interventions and trained at the same institution, more so at the top 25 hospitals.

Myocardial infarction with non-obstructive coronary arteries as compared with myocardial infarction and obstructive coronary disease: outcomes in a Medicare population.

AIMS: The prognosis of patients with MINOCA (myocardial infarction with non-obstructive coronary arteries) is poorly understood. We examined major adverse cardiac events (MACE) defined as all-cause mortality, re-hospitalization for acute myocardial infarction (AMI), heart failure (HF), or stroke 12-months post-AMI in patients with MINOCA versus AMI patients with obstructive coronary artery disease (MICAD). METHODS AND RESULTS: Multicentre, observational cohort study of patients with AMI (≥65 years) from the National Cardiovascular Data Registry CathPCI Registry (July 2009-December 2013) who underwent coronary angiography with linkage to the Centers for Medicare and Medicaid (CMS) claims data. Patients were classified as MICAD or MINOCA by the presence or absence of an epicardial vessel with ≥50% stenosis. The primary endpoint was MACE at 12 months, and secondary endpoints included the components of MACE over 12 months. Among 286 780 AMI admissions (276 522 unique patients), 16 849 (5.9%) had MINOCA. The 12-month rates of MACE (18.7% vs. 27.6%), mortality (12.3% vs. 16.7%), and re-hospitalization for AMI (1.3% vs. 6.1%) and HF (5.9% vs. 9.3%) were significantly lower for MINOCA vs. MICAD patients (P < 0.001), but was similar between MINOCA and MICAD patients for re-hospitalization for stroke (1.6% vs. 1.4%, P = 0.128). Following risk-adjustment, MINOCA patients had a 43% lower risk of MACE over 12 months (hazard ratio = 0.57, 95% confidence interval 0.55-0.59), in comparison to MICAD patients. This pattern was similar for adjusted risks of the MACE components. CONCLUSION: This study confirms an unfavourable prognosis in elderly patients with MINOCA undergoing coronary angiography, with one in five patients with MINOCA suffering a major adverse event over 12 months.

Modeling defibrillation benefit for survival among cardiac resynchronization therapy defibrillator recipients.

BACKGROUND: Patients with heart failure having a low expected probability of arrhythmic death may not benefit from implantable cardioverter defibrillators (ICDs). OBJECTIVE: The objective was to validate models to identify cardiac resynchronization therapy (CRT) candidates who may not require CRT devices with ICD functionality. METHODS: Heart failure (HF) patients with CRT-Ds and non-CRT ICDs from the National Cardiovascular Data Registry and others with no device from 3 separate registries and 3 heart failure trials were analyzed using multivariable Cox proportional hazards regression for survival with the Seattle Heart Failure Model (SHFM; estimates overall mortality) and the Seattle Proportional Risk Model (SPRM; estimates proportional risk of arrhythmic death). RESULTS: Among 60,185 patients (age 68.6 ±â€¯11.3 years, 31.9% female) meeting CRT-D criteria, 38,348 had CRT-Ds, 11,389 had non-CRT ICDs, and 10,448 had no device. CRT-D patients had a prominent adjusted survival benefit (HR 0.52, 95% CI 0.50-0.55, P < .0001 versus no device). CRT-D patients with SHFM-predicted 4-year survival ≥81% (median) and a low SPRM-predicted probability of an arrhythmic mode of death ≤42% (median) had an absolute adjusted risk reduction attributable to ICD functionality of just 0.95%/year with the majority of survival benefit (70%) attributable to CRT pacing. In contrast, CRT-D patients with SHFM-predicted survival median had substantially more ICD-attributable benefit (absolute risk reduction of 2.6%/year combined; P < .0001). CONCLUSIONS: The SPRM and SHFM identified a quarter of real-world, primary prevention CRT-D patients with minimal benefit from ICD functionality. Further studies to evaluate CRT pacemakers in these low-risk CRT candidates are indicated.

Facility Variation in Troponin Ordering Within the Veterans Health Administration.

BACKGROUND: Current United States guidelines recommend troponin as the preferred biomarker in assessing for acute coronary syndrome, but recommendations are limited about which patients to test. Variations in troponin ordering may influence downstream health care utilization. METHODS: We performed a cross-sectional analysis of 3,308,131 emergency department (ED) visits in all 121 acute care facilities within the Veterans Health Administration from 2015 to 2017. We quantified the degree to which case mix and facility characteristics accounted for variations in facility rates in troponin ordering. We then assessed the association between facility quartiles of risk-adjusted troponin ordering and downstream resource utilization [inpatient admissions, noninvasive testing (stress tests, echocardiograms), and invasive procedures (coronary angiograms, percutaneous coronary interventions, and coronary artery bypass grafting surgeries)]. RESULTS: The proportion of ED visits with troponin orders ranged from 2.2% to 64.5%, with a median of 37.1%. Case mix accounted for 9.5% of the variation in troponin orders; case mix and differences in facility characteristics accounted for 34.6%. Facilities in the highest quartile of troponin ordering, as compared with those in the lowest quartile, had significantly higher rates of inpatient admissions, stress tests, echocardiograms, coronary angiograms, and percutaneous coronary intervention. CONCLUSIONS: Significant variation in troponin utilization exists across Veterans Health Administration facilities and that variation is not well explained by case mix alone. Facilities with higher rates of troponin ordering were associated with more downstream resource utilization.

Stent selection among patients with chronic kidney disease: Results from the NCDR CathPCI Registry.

OBJECTIVES: This study sought to define contemporary rates of drug eluting stent (DES) usage in patients with chronic kidney disease (CKD). BACKGROUND: Among patients with CKD undergoing percutaneous coronary interventions (PCIs), outcomes are superior for those who receive DES compared to those who receive bare metal stents (BMSs). However, perceived barriers may limit the use of DES in this population. METHODS: All adult PCI cases from the NCDR CathPCI Registry involving coronary stent placement between July 1, 2009 and December 31, 2015 were analyzed. The rate of DES usage was then compared among four groups, stratified by CKD stage (I/II, III, IV, and V). Subgroup analysis was conducted based on PCI status and indication. Cases were linked to Medicare claims data to assess 1-year mortality. RESULTS: A total of 3,650,333 PCI cases met criteria for analysis. DES usage significantly declined as renal function worsened (83.0%, 79.9%, 75.6%, and 75.6%, respectively, in the four CKD stages; p < .001). DES usage was universally lower across the four groups in the setting of ST-Elevation Myocardial Infarction (STEMI) (70.6%, 66.5%, 58.7%, 58.0%; p < .001) and higher in the setting of elective PCI (87.6%, 84.9%, 82.3%, 77.9%; p < .0001). DES was associated with improved 1-year survival, and usage increased over time across each group. CONCLUSIONS: DESs are underutilized in patients with advanced renal dysfunction. Although DES usage has increased over time, variation still exists between patients with normal renal function and those with CKD.

Institutional Variation in Quality of Cardiovascular Implantable Electronic Device Implantation: A Cohort Study.

Background: Cardiovascular implantable electronic devices (CIEDs) are associated with procedure-related complications, yet little is known about variation in complication rates among institutions that may suggest disparities in care quality. Objective: To assess institutional variation in risk-standardized complication rates (RSCRs) for CIED. Design: Cohort study. Setting: 174 hospitals in Australia and New Zealand, 98 of which implanted at least 25 CIEDs during the study period. Participants: 81 304 patients older than 18 years (mean, 74.7 years [SD, 12.4]; 37.9% female) who received a new CIED (65 711 permanent pacemakers [PPMs] and 15 593 implantable cardioverter-defibrillators [ICDs]) in 2010 to 2015. Measurements: RSCRs and frequencies of major device-related complications during hospitalization or within 90 days of discharge. Results: Of the cohort, 6664 patients (8.2%) had a major complication. Although complication rates were higher for ICDs than PPMs (10.04% vs. 7.76%), 76.5% of all complications were attributable to PPMs (5098 vs. 1566 for ICDs). Among hospitals that implanted at least 25 CIEDs, the median RSCR was 8.1%; however, rates varied from 5.3% to 14.3%, with 22 hospitals identified as having RSCRs that differed significantly from the national average. Similar variation was observed when RSCRs for PPM implantation (n = 96 hospitals) (median RSCR, 7.6% [range, 5.4% to 12.9%]) were considered separately from those for ICD placement (n = 68 hospitals) (median RSCR, 9.7% [range, 6.2% to 16.9%]) and persisted when only elective procedures were assessed (n = 88 hospitals) (median RSCR, 7.4% [range, 4.7% to 13.0%]). Limitation: Possible unmeasured confounding from the use of administrative data. Conclusion: CIED complications are common and vary among hospitals, suggesting institutional variation in CIED care quality. Concerted clinical and policy interventions are needed to address CIED-related complications. These efforts should preferentially target PPMs, because most CIED complications are attributable to these devices. Primary Funding Source: The Hospitals Contribution Fund Research Foundation.

Association Between Industry Payments to Physicians and Device Selection in ICD Implantation.

Importance: Little is known about the association between industry payments and medical device selection. Objective: To examine the association between payments from device manufacturers to physicians and device selection for patients undergoing first-time implantation of a cardioverter-defibrillator (ICD) or cardiac resynchronization therapy-defibrillator (CRT-D). Design, Setting, and Participants: In this cross-sectional study, patients who received a first-time ICD or CRT-D device from any of the 4 major manufacturers (January 1, 2016-December 31, 2018) were identified. The data from the National Cardiovascular Data Registry ICD Registry was linked with the Open Payments Program's payment data. Patients were categorized into 4 groups (A, B, C, and D) corresponding to the manufacturer from which the physician who performed the implantation received the largest payment. For each patient group, the proportion of patients who received a device from the manufacturer that provided the largest payment to the physician who performed implantation was determined. Within each group, the absolute difference in proportional use of devices between the manufacturer that made the highest payment and the proportion of devices from the same manufacturer in the entire study cohort (expected prevalence) was calculated. Exposures: Manufacturers' payments to physicians who performed an ICD or CRT-D implantation. Main Outcomes and Measures: The primary outcome of the study was the manufacturer of the device used for the implantation. Results: Over a 3-year period, 145 900 patients (median age, 65 years; 29.6% women) received ICD or CRT-D devices from the 4 manufacturers implanted by 4435 physicians at 1763 facilities. Among these physicians, 4152 (94%) received payments from device manufacturers ranging from $2 to $323 559 with a median payment of $1211 (interquartile range, $390-$3702). Between 38.5% and 54.7% of patients received devices from the manufacturers that had provided physicians with the largest payments. Patients were substantially more likely to receive devices made by the manufacturer that provided the largest payment to the physician who performed implantation than they were from each other individual manufacturer. The absolute differences in proportional use from the expected prevalence were 22.4% (95% CI, 21.9%-22.9%) for manufacturer A; 14.5% (95% CI, 14.0%-15.0%) for manufacturer B; 18.8% (95% CI, 18.2%-19.4%) for manufacturer C; and 30.6% (95% CI, 30.0%-31.2%) for manufacturer D. Conclusions and Relevance: In this cross-sectional study, a large proportion of ICD or CRT-D implantations were performed by physicians who received payments from device manufacturers. Patients were more likely to receive ICD or CRT-D devices from the manufacturer that provided the highest total payment to the physician who performed an ICD or CRT-D implantation than each other manufacturer individually.

Association of Use of an Intravascular Microaxial Left Ventricular Assist Device vs Intra-aortic Balloon Pump With In-Hospital Mortality and Major Bleeding Among Patients With Acute Myocardial Infarction Complicated by Cardiogenic Shock.

Importance: Acute myocardial infarction (AMI) complicated by cardiogenic shock is associated with substantial morbidity and mortality. Although intravascular microaxial left ventricular assist devices (LVADs) provide greater hemodynamic support as compared with intra-aortic balloon pumps (IABPs), little is known about clinical outcomes associated with intravascular microaxial LVAD use in clinical practice. Objective: To examine outcomes among patients undergoing percutaneous coronary intervention (PCI) for AMI complicated by cardiogenic shock treated with mechanical circulatory support (MCS) devices. Design, Setting, and Participants: A propensity-matched registry-based retrospective cohort study of patients with AMI complicated by cardiogenic shock undergoing PCI between October 1, 2015, and December 31, 2017, who were included in data from hospitals participating in the CathPCI and the Chest Pain-MI registries, both part of the American College of Cardiology's National Cardiovascular Data Registry. Patients receiving an intravascular microaxial LVAD were matched with those receiving IABP on demographics, clinical history, presentation, infarct location, coronary anatomy, and clinical laboratory data, with final follow-up through December 31, 2017. Exposures: Hemodynamic support, categorized as intravascular microaxial LVAD use only, IABP only, other (such as use of a percutaneous extracorporeal ventricular assist system, extracorporeal membrane oxygenation, or a combination of MCS device use), or medical therapy only. Main Outcomes and Measures: The primary outcomes were in-hospital mortality and in-hospital major bleeding. Results: Among 28 304 patients undergoing PCI for AMI complicated by cardiogenic shock, the mean (SD) age was 65.0 (12.6) years, 67.0% were men, 81.3% had an ST-elevation myocardial infarction, and 43.3% had cardiac arrest. Over the study period among patients with AMI, an intravascular microaxial LVAD was used in 6.2% of patients, and IABP was used in 29.9%. Among 1680 propensity-matched pairs, there was a significantly higher risk of in-hospital death associated with use of an intravascular microaxial LVAD (45.0%) vs with an IABP (34.1% [absolute risk difference, 10.9 percentage points {95% CI, 7.6-14.2}; P < .001) and also higher risk of in-hospital major bleeding (intravascular microaxial LVAD [31.3%] vs IABP [16.0%]; absolute risk difference, 15.4 percentage points [95% CI, 12.5-18.2]; P < .001). These associations were consistent regardless of whether patients received a device before or after initiation of PCI. Conclusions and Relevance: Among patients undergoing PCI for AMI complicated by cardiogenic shock from 2015 to 2017, use of an intravascular microaxial LVAD compared with IABP was associated with higher adjusted risk of in-hospital death and major bleeding complications, although study interpretation is limited by the observational design. Further research may be needed to understand optimal device choice for these patients.

Ventricular Fibrillation Conversion Testing After Implantation of a Subcutaneous Implantable Cardioverter Defibrillator: Report From the National Cardiovascular Data Registry.

BACKGROUND: Compared with transvenous implantable cardioverter defibrillators (ICDs), subcutaneous (S)-ICDs require a higher energy for effective defibrillation. Although ventricular fibrillation conversion testing (CT) is recommended after S-ICD implantation to ensure an adequate margin between the defibrillation threshold and maximum device output (80J), prior work found that adherence to this recommendation is declining. METHODS: We studied first-time recipients of S-ICDs (between September 28, 2012, and April 1, 2016) in the National Cardiovascular Database Registry ICD Registry to determine predictors of use of CT, predictors of an insufficient safety margin (ISM, defined as ventricular fibrillation conversion energy >65J) during testing, and inhospital outcomes associated with use of CT. Multivariable logistic regression analysis was used to predict use of CT and ISM. Inverse probability weighted logistic regression analysis was used to examine the association between use of CT and inhospital adverse events including death. RESULTS: CT testing was performed in 70.7% (n=5624) of 7960 patients with S-ICDs. Although deferral of CT was associated with several patient characteristics (including increased body mass index, increased body surface area, severely reduced ejection fraction, dialysis dependence, warfarin use, anemia, and hypertrophic cardiomyopathy), the facility effect was comparatively more important (area under the curve for patient level versus generalized linear mixed model: 0.619 versus 0.877). An ISM occurred in 6.9% (n=336) of 4864 patients without a prior ICD and was more common among white patients and those with ventricular pacing on the preimplant ECG, higher preimplant blood pressure, larger body surface area, higher body mass index, and lower ejection fraction. A risk score was able to identify patients at low (<5%), medium (5% to 10%), and high risk (>10%) for ISM. CT testing was not associated with a composite of inhospital complications including death. CONCLUSIONS: Use of CT testing after S-ICD implantation was driven by facility preference to a greater extent than patient factors and was not associated with a composite of inhospital complications or death. ISM was relatively uncommon and is associated with several widely available patient characteristics. These data may inform ICD system selection and a targeted approach to CT.

Heart Failure After Ischemic Stroke or Transient Ischemic Attack in Insulin-Resistant Patients Without Diabetes Mellitus Treated With Pioglitazone.

BACKGROUND: The IRIS trial (Insulin Resistance Intervention After Stroke) demonstrated that pioglitazone reduced the risk for both cardiovascular events and diabetes mellitus in insulin-resistant patients. However, concern remains that pioglitazone may increase the risk for heart failure (HF) in susceptible individuals. METHODS: In IRIS, patients with insulin resistance but without diabetes mellitus were randomized to pioglitazone or placebo (1:1) within 180 days of an ischemic stroke or transient ischemic attack and followed for ≤5 years. To identify patients at higher HF risk with pioglitazone, we performed a secondary analysis of IRIS participants without HF history at entry. HF episodes were adjudicated by an external review, and treatment effects were analyzed using time-to-event methods. A baseline HF risk score was constructed from a Cox model estimated using stepwise selection. Baseline patient features (individually and summarized in risk score) and postrandomization events were examined as possible modifiers of the effect of pioglitazone. Net cardiovascular benefit was estimated for the composite of stroke, myocardial infarction, and hospitalized HF. RESULTS: Among 3851 patients, the mean age was 63 years, and 65% were male. The 5-year HF risk did not differ by treatment (4.1% pioglitazone, 4.2% placebo). Risk for hospitalized HF was low and not significantly greater in pioglitazone compared with placebo groups (2.9% versus 2.3%, P=0.36). Older age, atrial fibrillation, hypertension, obesity, edema, high C-reactive protein, and smoking were risk factors for HF. However, the effect of pioglitazone did not differ across levels of baseline HF risk (hazard ratio [95% CI] for pioglitazone versus placebo for patients at low, moderate, and high risk: 1.03 [0.61-1.73], 1.10 [0.56-2.15], and 1.08 [0.58-2.01]; interaction P value=0.98). HF risk was increased in patients with versus those without incident myocardial infarction in both groups (pioglitazone: 31.4% versus 2.7%; placebo: 25.7% versus 2.4%; P<0.0001). Edema, dyspnea, and weight gain in the trial did not predict HF hospitalization but led to more study drug dose reduction with a lower mean dose of pioglitazone versus placebo (29±17 mg versus 33±15 mg, P<0.0001). Pioglitazone reduced the composite outcome of stroke, myocardial infarction, or hospitalized HF (hazard ratio, 0.78; P=0.007). CONCLUSIONS: In IRIS, with surveillance and dose adjustments, pioglitazone did not increase the risk of HF and conferred net cardiovascular benefit in patients with insulin resistance and cerebrovascular disease. The risk of HF with pioglitazone was not modified by baseline HF risk. The IRIS experience may be instructive for maximizing the net benefit of this therapy. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov . Unique identifier: NCT00091949.