Assessment of Repeat Revascularization in Percutaneous Coronary Intervention Randomized Controlled Trials as a Surrogate for Mortality: A Meta-Regression Analysis.

The association of repeat revascularization after percutaneous coronary intervention (PCI) with mortality is uncertain. To assess the association of repeat revascularization after PCI with mortality in patients with coronary artery disease (CAD). We identified randomized controlled trials comparing PCI with coronary artery bypass graft (CABG) or optimal medical therapy (OMT) using electronic databases through January 1, 2022. We performed a random-effects meta-regression between repeat revascularization rates after PCI (absolute risk difference [%] between PCI and CABG or OMT) with the relative risks (RR) of mortality. We assessed surrogacy of repeat revascularization for mortality using the coefficient of determination (R2), with threshold of 0.80. In 33 trials (21,735 patients), at median follow-up of 4 (2-7) years, repeat revascularization was higher after PCI than CABG [RR: 2.45 (95% confidence interval, 1.99-3.03)], but lower vs OMT [RR: 0.64 (0.46-0.88)]. Overall, meta-regression showed that repeat revascularization rates after PCI had no significant association with all-cause mortality [RR: 1.01 (0.99-1.02); R2=0.10) or cardiovascular mortality [RR: 1.01 (CI: 0.99-1.03); R2=0.09]. In PCI vs CABG (R2=0.0) or PCI vs OMT trials (R2=0.28), repeat revascularization did not meet the threshold for surrogacy for all-cause or cardiovascular mortality (R2=0.0). We observed concordant results for subgroup analyses (enrollment time, follow-up, sample size, risk of bias, stent types, and coronary artery disease), and multivariable analysis adjusted for demographics, comorbidities, risk of bias, MI, and follow-up duration. In summary, this meta-regression did not establish repeat revascularization after PCI as a surrogate for all-cause or cardiovascular mortality.

The Implications of Acute Clinical Care Responsibilities on the Contemporary Practice of Interventional Cardiology.

The responsibilities of the interventional cardiologist (IC) have evolved in contemporary practice to include substantial acute care clinical duties outside of the cardiac catheterization laboratory. In particular, the IC has assumed a central role in the global management of myocardial infarction and other acute coronary syndromes in the intensive care unit and beyond. These duties have expanded to include many nonprocedural tasks. The Interventional Section Leadership Council (ISLC) of the American College of Cardiology (ACC) therefore recommends: 1) these implications should be directly considered in the ACC's future planning and policy statements concerning manpower, competence, education, and reimbursement; 2) the development of an acute care cardiology subspecialty should be undertaken; 3) steps should be taken to adjust the number of ICs primarily on the basis of optimizing procedural volume and quality; and 4) the annual number of coronary interventions performed should not solely define competence in the future, but should include the performance of acute cardiology responsibilities.

Transcatheter aortic valve replacement in patients with severe mitral or tricuspid regurgitation at extreme risk for surgery.

OBJECTIVES: Patients with symptomatic severe aortic stenosis and severe mitral regurgitation or severe tricuspid regurgitation were excluded from the major transcatheter aortic valve replacement trials. We studied these 2 subgroups in patients at extreme risk for surgery in the prospective, nonrandomized, single-arm CoreValve US Expanded Use Study. METHODS: The primary end point was all-cause mortality or major stroke at 1 year. A favorable medical benefit was defined as a Kansas City Cardiomyopathy Questionnaire overall summary score greater than 45 at 6 months and greater than 60 at 1 year and with a less than 10-point decrease from baseline. RESULTS: There were 53 patients in each group. Baseline characteristics for the severe mitral regurgitation and severe tricuspid regurgitation cohorts were age 84.2 ± 6.4 years and 84.9 ± 6.5 years; male, 29 (54.7%) and 22 (41.5%), and mean Society of Thoracic Surgeons score 9.9% ± 5.0% and 9.2% ± 4.0%, respectively. Improvement in valve regurgitation from baseline to 1 year occurred in 72.7% of the patients with severe mitral regurgitation and in 61.8% of patients with severe tricuspid regurgitation. A favorable medical benefit occurred in 31 of 47 patients (66.0%) with severe mitral regurgitation and 33 of 47 patients (70.2%) with severe tricuspid regurgitation at 6 months, and in 25 of 44 patients (56.8%) with severe mitral regurgitation and 24 of 45 patients (53.3%) with severe tricuspid regurgitation at 1 year. All-cause mortality or major stroke for the severe mitral regurgitation and severe tricuspid regurgitation cohorts were 11.3% and 3.8% at 30 days and 21.0% and 19.2% at 1 year, respectively. There were no major strokes in either group at 1 year. CONCLUSIONS: Transcatheter aortic valve replacement in patients with severe mitral regurgitation or severe tricuspid regurgitation is reasonable and safe and leads to improvement in atrioventricular valve regurgitation.

Regional Variation in Utilization, In-hospital Mortality, and Health-Care Resource Use of Transcatheter Aortic Valve Implantation in the United States.

We queried the National Inpatient Sample database from 2012 to 2014 to identify all patients aged ≥18 years undergoing transcatheter aortic valve implantation (TAVI) in the United States. Regional differences in TAVI utilization, in-hospital mortality, and health-care resource use were analyzed. Of 41,025 TAVI procedures in the United States between 2012 and 2014, 10,390 were performed in the Northeast, 9,090 in the Midwest, 14,095 in the South, and 7,450 in the West. Overall, the number of TAVI implants per million adults increased from 24.8 in 2012 to 63.2 in 2014. The utilization of TAVI increased during the study period in all 4 geographic regions, with the number of implants per million adults being highest in the Northeast, followed by the Midwest, South, and West, respectively. Overall in-hospital mortality was 4.2%. Compared with the Northeast, risk-adjusted in-hospital mortality was higher in the Midwest (adjusted odds ratio [aOR] 1.26 [1.07 to 1.48]) and the South (aOR 1.61 [1.40 to 1.85]) and similar in the West (aOR 1.00 [0.84 to 1.18]). Average length of stay was shorter in all other regions compared with the Northeast. Among patients surviving to discharge, disposition to a skilled nursing facility or home health care was most common in the Northeast, whereas home discharge was most common in the West. Average hospital costs were highest in the West. In conclusion, we observed significant regional differences in TAVI utilization, in-hospital mortality, and health-care resource use in the United States. The findings of our study may have important policy implications and should provide an impetus to understand the source of this regional variation.

Association Between Hospital Volume and 30-Day Readmissions Following Transcatheter Aortic Valve Replacement.

Importance: With the approval of transcatheter aortic valve replacement (TAVR) for patients with severe symptomatic aortic stenosis at intermediate surgical risk, TAVR volume is projected to increase exponentially in the United States. The 30-day readmission rate for TAVR was recently reported at 17.9%. The association between institutional TAVR volume and the 30-day readmission metric has not been examined. Objective: To assess the association between hospital TAVR volume and 30-day readmission. Design, Setting, and Participants: In this observational study, we used the 2014 Nationwide Readmissions Database to identify hospitals with established TAVR programs (performing at least 5 TAVRs in the first quarter of 2014). Based on annual TAVR volume, hospitals were classified as low (<50), medium (≥50 to <100), and high (≥100) volume. Rates, causes, and costs of 30-day readmissions were compared between low-, medium-, and high-volume hospitals. Data were analyzed from November to December 2016. Exposure: Transcatheter aortic valve replacement. Main Outcomes and Measures: Thirty-day readmissions. Results: Of 129 hospitals included in this study, 20 (15.5%) were categorized as low volume, 47 (36.4%) as medium volume, and 62 (48.1%) as high volume. Of 16 252 index TAVR procedures, 663 (4.1%), 3067 (18.9%), and 12 522 (77.0%) were performed at low-, medium-, and high-volume hospitals, respectively. Thirty-day readmission rates were significantly lower in high-volume compared with medium-volume (adjusted odds ratio, 0.76; 95% CI, 0.68-0.85; P < .001) and low-volume (adjusted odds ratio, 0.75; 95% CI, 0.60-0.92; P = .007) hospitals. Noncardiac readmissions were more common in low-volume hospitals (65.6% vs 60.6% in high-volume hospitals), whereas cardiac readmissions were more common in high-volume hospitals (39.4% vs 34.4% in low-volume hospitals). There were no significant differences in length of stay and costs per readmission among the 3 groups (mean [SD], 5.5 [5.0] days vs 5.9 [7.5] days vs 6.0 [5.8] days; P = .74, and $13 886 [18 333] vs $14 135 [17 939] vs $13 432 [15 725]; P = .63, respectively). Conclusions and Relevance: We report for the first time, to our knowledge, an inverse association between hospital TAVR volume and 30-day readmissions. Lower readmission at higher-volume hospitals was associated with significantly lower cost to the health care system.

Survival benefit with drug-eluting stents in observational studies: fact or artifact?

BACKGROUND: Recently, there has been increased interest in leveraging observational studies for comparative effectiveness research. Without robust and valid risk adjustment, however, findings from these nonrandomized studies may remain biased. Previous studies examining long-term mortality with drug-eluting stents (DESs) have demonstrated discordant results between randomized trials and observational studies. To examine the impact of treatment selection bias on these findings, we used data from a prospective percutaneous coronary intervention (PCI) registry (EVENT [Evaluation of Drug Eluting Stents and Ischemic Events]) to compare clinical outcomes between DESs and bare metal stents (BMSs) using conventional (multivariable regression and propensity matching) and novel (instrumental variable analysis) risk-adjustment techniques. METHODS AND RESULTS: The study population consisted of 9266 patients who underwent nonemergent PCI with stent placement at 55 US centers between 2004 and 2007. All-cause mortality and target lesion revascularization (TLR) were assessed prospectively over 1 year of follow-up. Overall, 8171 patients (88%) received DES, but this proportion substantially differed by treatment year (93% in 2004-2006 and 73% in 2007; P<0.001). One-year rates of death and TLR were significantly lower with DES versus BMS (death, 2.5% versus 5.6%; TLR, 4.2% versus 6.9%; P<0.001 for both), findings that persisted in both multivariable-adjusted and propensity-matched analyses. In contrast, instrumental variable analysis, using enrollment period (2004-2006 versus 2007) as the instrument, demonstrated no significant difference in 1-year mortality (predicted absolute difference, 2.0%; 95% CI, -1.8% to 5.7%; P=0.30) and a strong trend toward reduced TLR with DES use (predicted absolute difference, -4.2%; 95% CI, -8.8% to 0.4%; P=0.07). CONCLUSIONS: Among unselected PCI patients in contemporary practice, DES use tended to be associated with a consistent reduction in TLR regardless of risk-adjustment method but showed discordant effects on mortality with conventional risk adjustment compared with instrumentable variable analysis. These findings underscore the limitations of standard risk-adjustment methods to adequately address treatment selection bias in nonrandomized studies and have important implications for comparative effectiveness research using observational data.

Clinical and economic outcomes of liberal versus selective drug-eluting stent use: insights from temporal analysis of the multicenter Evaluation of Drug Eluting Stents and Ischemic Events (EVENT) registry.

BACKGROUND: Although the benefits of drug-eluting stents (DES) for reducing restenosis after percutaneous coronary intervention are well established, the impact of alternative rates of DES use on population-level outcomes is unknown. METHODS AND RESULTS: We used data from the Evaluation of Drug Eluting Stents and Ischemic Events (EVENT) registry to examine the clinical impact and cost-effectiveness of varying DES use rates in routine care. Between 2004 and 2007, 10,144 patients undergoing percutaneous coronary intervention were enrolled in the EVENT registry at 55 US centers. Clinical outcomes and cardiovascular-specific costs were assessed prospectively over 1 year of follow-up. Use of DES decreased from 92 in 2004 to 2006 (liberal use era; n=7587) to 68 in 2007 (selective use era; n=2557; P<0.001). One-year rates of death or myocardial infarction were similar in both eras. Over this time period, the incidence of target lesion revascularization increased from 4.1 to 5.1, an absolute increase of 1.0 (95 confidence interval, 0.1 to 1.9; P=0.03), whereas total cardiovascular costs per patient decreased by $401 (95 confidence interval, 131 to 671; P=0.004). The risk-adjusted incremental cost-effectiveness ratio for the liberal versus selective DES era was $16,000 per target lesion revascularization event avoided, $27,000 per repeat revascularization avoided, and $433 000 per quality-adjusted life-year gained. CONCLUSIONS: In this prospective registry, a temporal reduction in DES use was associated with a small increase in target lesion revascularization and a modest reduction in total cardiovascular costs. These findings suggest that although clinical outcomes are marginally better with unrestricted DES use, this approach represents a relatively inefficient use of healthcare resources relative to several common benchmarks for cost-effective care.

Cardiogenic shock and heart failure post-percutaneous coronary intervention in ST-elevation myocardial infarction: observations from "Assessment of Pexelizumab in Acute Myocardial Infarction".

BACKGROUND: Mortality after ST-elevation myocardial infarction (STEMI) has reduced with reperfusion by primary percutaneous coronary intervention (PCI), which may have impacted on the adverse outcomes of cardiogenic shock (CS) and congestive heart failure (CHF). METHODS AND RESULTS: In the APEX-AMI trial, 5,745 patients with STEMI and planned primary PCI were randomly assigned pexelizumab or matching placebo. Post-randomization CS or CHF was adjudicated by a clinical endpoints committee. Treatment assignment to pexelizumab did not influence either endpoint or mortality rates. Cardiogenic shock developed in 196 patients (3.4%) at a median of 6.0 hours (interquartile range 3.9-28.3) post-randomization, and mortality at 90 days was 54.6%. Congestive heart failure occurred in 254 of patients (4.4%) at a median of 2.6 days (IQR 1.0-16.6), and mortality through 90 days was 10.2%; mortality among those with neither endpoint was 2.1%. Patients with CS or CHF were older, were more often female, and had more hypertension and diabetes, but smoked less compared with non-CS/CHF patients (all P < .05). Independent mortality predictors among those with CS or CHF were hyperlipidemia and a history of angina (interaction P = .011 and .008, respectively); procedural predictors among survivors to PCI were pre-PCI Thrombolysis In Myocardial Infarction (TIMI) flow 0-1 and post-PCI TIMI flow <3 (P = .013 and <.0001, respectively). CONCLUSIONS: Survival after CS remains poor despite aggressive reperfusion. Both CS and CHF remain the major causes of death among STEMI patients undergoing primary PCI. Future studies should examine treatments that aim to reduce mortality in these highest risk patients.

Strategic lessons from the clinical event classification process for the Assessment of Pexelizumab in Acute Myocardial Infarction (APEX-AMI) trial.

BACKGROUND: Independent adjudication of clinical trial events is traditionally performed by physicians on a clinical event classification (CEC) committee. OBJECTIVES: The experience of the centralized CEC group of the APEX-AMI trial is described. This group adjudicated key secondary pre-specified outcome measures of congestive heart failure (CHF) and cardiogenic shock through 90 days using an algorithmic approach for some events. METHODS: Data were collected via an electronic data capture (EDC) tool on all subjects, and additional information was provided via EDC for patients identified by site investigators with CHF or shock. Two strategies were used to adjudicate potential events: 1) a computer algorithm (followed by physician confirmation) analyzed data to determine whether events met trial end point definitions; or 2) physician review was used if EDC data were inadequate to allow classification by algorithm. RESULTS: Of 5745 patients, 282 suspected cardiogenic shock and 465 suspected CHF events were identified. The computer algorithm or physicians confirmed 196/282 cardiogenic shock and 277/465 CHF end points. Overall, 242/742 (32.6%) of suspected events were classified by algorithm. Of the 500 events not resolved by computer algorithm, the CEC physicians agreed with site investigator assessments in 126/277 (45%) of CHF and 151/196 (77%) of cardiogenic shock events. The CEC committee completed adjudication of all suspected 30- and 90-day CHF and cardiogenic shock events within 7 days of the last patient 30-day follow-up visit and within 1 day of the last patient 90-day follow-up visit. Only 27% of patients required source document collection in addition to EDC-collected information. CONCLUSIONS: A complementary approach of a computerized assessment and physician review was used in the CEC effort of the APEX-AMI trial. The algorithm categorized approximately one third of suspected CHF/cardiogenic shock events. The APEX-AMI CEC experience shows that an algorithmic approach may be a useful strategy for end point evaluation but requires validation.

Assessment, mechanisms, and clinical implication of variability in platelet response to aspirin and clopidogrel therapy.

Antiplatelet therapy is the mainstay of treatment for patients with cardiovascular disease. However, some patients experience adverse cardiac events despite treatment with single- or dual-antiplatelet (aspirin and clopidogrel) therapy. Some of those events could be caused by low responsiveness to aspirin or clopidogrel. The frequency of this phenomenon has been reported to range from 1% to 45% for the 2 drugs. This wide range arises from the lack of a "gold-standard" definition to assess antiplatelet drug response and differences in assays, agonist concentrations, and cut-off points. Regardless of the variability in the incidence of aspirin or clopidogrel low responsiveness, several studies have indicated a clear relation between clopidogrel or aspirin low responsiveness and cardiovascular events. The evidence for an association between adverse clinical events and the results of ex vivo platelet function tests is stronger for clopidogrel than for aspirin. Currently, there is no established therapeutic approach for managing low response to aspirin or clopidogrel that has been shown in large trials to have clinical benefit. This review focuses on laboratory testing of antiplatelet response to aspirin and clopidogrel, the prevalence of low response, potential mechanisms, clinical significance, and prognostic value of this phenomenon and alternative approaches to optimize treatment in patients with low response to the drugs.

Outcomes of patients with acute coronary syndromes who are treated with bivalirudin during percutaneous coronary intervention: an analysis from the Randomized Evaluation in PCI Linking Angiomax to Reduced Clinical Events (REPLACE-2) trial.

BACKGROUND: The REPLACE-2 trial demonstrated that bivalirudin with provisional glycoprotein IIb/IIIa (GPIIb/IIIa) inhibition is not inferior to heparin plus GPIIb/IIIa inhibition in patients undergoing percutaneous coronary intervention. The extent to which this applies to patients with acute coronary syndromes (ACS) is unclear. Therefore, we sought to determine if bivalirudin has similar efficacy in ACS patients as compared with "stable" patients in the REPLACE-2 trial. METHODS: We analyzed the outcomes of ACS patients compared with stable patients and the outcomes of ACS patients according to whether or not they had received bivalirudin, including the economic costs. The trial enrolled 1351 ACS patients (myocardial infarction within 7 days or unstable angina within 48 hours, but not on ongoing GPIIb/IIIa or heparin therapy) and 4554 stable patients. RESULTS: Patients with ACS had a similar rate of death or myocardial infarction at 30 days compared to stable patients (7.2% vs 6.7%, P = .51) and death at 1 year (1.6% vs 2.2%, P = .169), but a higher rate of urgent coronary artery bypass graft at 30 days (1.0% vs 0.3%, P = .002). Patients with ACS treated with bivalirudin had a similar rate of 30-day death, myocardial infarction, or urgent revascularization compared with ACS patients treated with heparin and GPIIb/IIIa inhibitors (8.7% vs 8.0%, P = .616) and death at 1 year (1.5% vs 1.8%, P = .701), but a higher rate of revascularization at 6 months (12% vs 8.4%, P = .04). Patients with ACS treated with bivalirudin had less major bleeding than ACS patients treated with heparin and GPIIb/IIIa inhibitors, although this was not statistically significant (2.7% vs 4.5%, P = .07). Mean 30-day costs for patients with ACS were dollar 12415 for those treated with bivalirudin and dollar 12806 for those treated with heparin plus GPIIb/IIIa inhibitors (P = .022). CONCLUSION: Bivalirudin with provisional GPIIb/IIIa inhibitor use in low-risk ACS patients (not receiving preprocedural GPIIb/IIIa blockade) appears to provide similar protection against death and myocardial infarction as the combination of heparin and GPIIb/IIIa inhibitors, although we observed a higher rate of revascularization at 6 months.

Glycoprotein IIb-IIIa inhibition with abciximab and postprocedural risk assessment: lessons from the evaluation of platelet IIb/IIIa inhibitor for stenting trial and implication for ad hoc use of glycoprotein IIb-IIIa antagonists.

BACKGROUND: Angiographic features of vessels in which stents have been deployed can be used to predict the risk of postprocedural ischemic events. The purpose of this study was to compare the effects of abciximab in patients with and without high-risk postprocedure features. METHODS AND RESULTS: Protocol-mandated stent implantation was performed in 1586 patients in the Evaluation of Platelet IIb/IIIa Inhibitor for Stenting trial, 783 of whom received abciximab, and was successful in 97% of the patients. High-risk features were defined as the presence of Thrombolysis In Myocardial Infarction (TIMI) flow <3, presence of thrombus or major dissection, or residual stenosis >10%. The primary endpoint was a composite of death, myocardial infarction, and urgent target vessel revascularization at 30 days. High-risk features were present in 21% of the patients. In patients without high-risk features after stent placement, abciximab reduced the primary endpoint from 9.0% to 3.9% (P <.001) compared with 16.2% to 8.6% (P =.046) in patients in whom high-risk features were present. There was no statistical evidence of interaction between abciximab treatment and the presence or absence of high-risk features. CONCLUSION: Glycoprotein IIb-IIIa antagonism with abciximab is equally effective in prevention of a composite of ischemic events in patients with and without high-risk features after stent placement. However, patients in whom high-risk features are present after stent placement are at increased risk of ischemic cardiac events even with abciximab treatment.