Nationwide Analysis of Patients With ST-Segment–Elevation Myocardial Infarction Transferred for Primary Percutaneous Intervention

Background—

Current American College of Cardiology/American Heart Association guidelines recommend transfer and primary percutaneous coronary intervention (PCI) for ST-segment–elevation myocardial infarction (STEMI) patients within the time limit of first contact to device ≤120 minutes. We determined the hospital-level, patient-level, and process characteristics of timely versus delayed primary PCI for a diverse national sample of transfer patients confined to a travel distance that facilitates the process.

Methods and Results—

We studied 14 518 patients transferred from non–PCI-capable hospitals for primary PCI to 398 National Cardiovascular Data Registry Acute Coronary Treatment and Intervention Outcomes Network Registry-Get With The Guidelines hospitals between July 2008 and December 2012. Patients with estimated transfer times >60 minutes (by Google Maps driving times) were excluded from the analysis. Patients achieving first door-to-device time ≤120 minutes were compared with patients with delayed treatment; independent predictors of timely treatment were determined using generalized estimating equations logistic regression models. The median estimated transfer distance was 26.5 miles. First door-to-device ≤120 minutes was achieved in 65% of patients (n=9380); only 37% of the hospitals were high-performing hospitals (defined as risk-adjusted rate, ≥75% of transfer STEMI patients with ≤120-minute first door-to-device time). In addition to known predictors of delay (cardiogenic shock, cardiac arrest, and prolonged door-in door-out time), STEMI referral hospitals’ rural location and longer estimated transfer time were identified as predictors of delay. In this diverse national sample, regional and racial variations in care were observed. Finally, lower PCI hospital annual STEMI volume was a potent predictor of delay.

Conclusions—

More than one third of US STEMI patients transferred for primary PCI fail to achieve first door-to-device time ≤120 minutes, despite estimated transfer times <60 minutes. Delays are related to process variables, comorbidities, and lower annual PCI hospital STEMI volumes.

Fibrinolysis use among patients requiring interhospital transfer for ST-segment elevation myocardial infarction care: a report from the US National Cardiovascular Data Registry

IMPORTANCE

Guidelines for patients with ST-segment elevation myocardial infarction (STEMI) recommend timely reperfusion with primary percutaneous coronary intervention (pPCI) or fibrinolysis. Among patients with STEMI who require interhospital transfer, it is unclear how reperfusion strategy selection and outcomes vary with interhospital drive times.

OBJECTIVE

To assess the association of estimated interhospital drive times with reperfusion strategy selection among transferred patients with STEMI in the United States.

DESIGN, SETTING, AND PARTICIPANTS

We identified 22,481 patients eligible for pPCI or fibrinolysis who were transferred from 1771 STEMI referring centers to 366 STEMI receiving centers in the Acute Coronary Treatment and Intervention Outcomes Network Registry-Get With the Guidelines database between July 1, 2008, and March 31, 2012.

MAIN OUTCOMES AND MEASURES

In-hospital mortality and major bleeding.

RESULTS

The median estimated interhospital drive time was 57 minutes (interquartile range [IQR], 36-88 minutes). When the estimated drive time exceeded 30 minutes, only 42.6% of transfer patients treated with pPCI achieved the first door-to-balloon time within 120 minutes. Only 52.7% of eligible patients with a drive time exceeding 60 minutes received fibrinolysis. Among 15,437 patients with estimated drive times of 30 to 120 minutes who were eligible for fibrinolysis or pPCI, 5296 (34.3%) received pretransfer fibrinolysis, with a median door-to-needle time of 34 minutes (IQR, 23-53 minutes). After fibrinolysis, the median time to transfer to the STEMI receiving center was 49 minutes (IQR, 34-69 minutes), and 97.1% underwent follow-up angiography. Patients treated with fibrinolysis vs pPCI had no significant mortality difference (3.7% vs 3.9%; adjusted odds ratio, 1.13; 95% CI, 0.94-1.36) but had higher bleeding risk (10.7% vs 9.5%; adjusted odds ratio, 1.17; 95% CI, 1.02-1.33).

CONCLUSIONS AND RELEVANCE

In the United States, neither fibrinolysis nor pPCI is being optimally used to achieve guideline-recommended reperfusion targets. For patients who are unlikely to receive timely pPCI, pretransfer fibrinolysis, followed by early transfer for angiography, may be a reperfusion option when potential benefits of timely reperfusion outweigh bleeding risk.

Comparative Effectiveness and Safety of a Catheterization Laboratory–Only Eptifibatide Dosing Strategy in Patients Undergoing Percutaneous Coronary Intervention

Background—

Eptifibatide, a small-molecule glycoprotein IIb/IIIa inhibitor, is conventionally administered as a bolus plus infusion. A growing number of clinicians are using a strategy of catheterization laboratory–only eptifibatide (an off-label use) as procedural pharmacotherapy for patients undergoing percutaneous coronary intervention although the comparative effectiveness of this approach is unknown.

Methods and Results—

We compared the in-hospital outcome of patients undergoing percutaneous coronary intervention across 47 hospitals and treated with eptifibatide bolus plus infusion with those treated with a catheterization laboratory–only regimen. We used optimal matching to link the use of catheterization laboratory–only eptifibatide with clinical outcomes, including mortality, myocardial infarction, bleeding, and need for transfusion. Of the 84 678 percutaneous coronary interventions performed during 2010 to 2011, and meeting our inclusion criteria, eptifibatide was administered to 21 296 patients. Of these, a catheterization laboratory–only regimen was used in 4511 patients, whereas 16 785 patients were treated with bolus plus infusion. In the optimally matched analysis, compared with bolus plus infusion, a catheterization laboratory–only regimen was associated with a reduction in bleeding (optimally matched adjusted odds ratio, 0.74; 95% confidence interval, 0.58–0.93; P =0.014) and need for transfusion (optimally matched adjusted odds ratio, 0.70; 95% confidence interval, 0.52–0.92; P =0.012), with no difference in mortality or myocardial infarction.

Conclusions—

A catheterization laboratory–only eptifibatide regimen is commonly used in clinical practice and is associated with a significant reduction in bleeding complications in patients undergoing contemporary percutaneous coronary intervention.

How can we optimize the processes of care for acute coronary syndromes to improve outcomes?

Acute coronary syndromes (ACS), either ST-elevation myocardial infarction or non-ST-elevation ACS, are still one of the most common cardiac emergencies with substantial morbidity and mortality. The availability of evidence-based treatments, such as early and intense platelet inhibition and anticoagulation, and timely reperfusion and revascularization, has substantially improved outcomes in patients with ACS. The implementation of streamlined processes of care for patients with ST-elevation myocardial infarction and non-ST-elevation ACS over the last decade including both appropriate tools, especially cardiac troponin, for rapid diagnosis and risk stratification and for decision support, and the widespread availability of modern antithrombotic and interventional treatments, have reduced morbidity and mortality to unprecedented low levels. These changes in the process of care require a synchronized approach, and research using a team-based strategy and effective regional networks has allowed healthcare systems to provide modern treatments for most patients with ACS. There are still areas needing improvement, such as the delivery of care to people in rural areas or with delayed time to treatment.

Antiplatelet and anticoagulation agents in acute coronary syndromes: what is the current status and what does the future hold?

Mortality and morbidity in acute coronary syndromes (ACSs), caused principally by plaque erosion or rupture leading to thrombus formation and myocardial ischemia, have been reduced by a combination of antithrombotic agents (antiplatelet drugs and anticoagulants) and early revascularization. Aspirin is the foundation antiplatelet agent. New P2Y12 receptor inhibitors (prasugrel and ticagrelor) have clear benefits compared with clopidogrel for dual antiplatelet therapy, and cangrelor or vorapaxar, a thrombin receptor inhibitor, may be of value in specific settings. Anticoagulation uses 1 of 4 choices: bivalirudin, unfractionated heparin, enoxaparin, and fondaparinux. Moreover, some patients (such as those who have chronic atrial fibrillation) require triple therapy with aspirin, clopidogrel, plus an anticoagulant, frequently a vitamin K antagonist. New oral anticoagulants have been shown to be at least as effective as vitamin K antagonists in atrial fibrillation and led to fewer bleeding complications. Finally, the combination of aspirin, clopidogrel, and low-dose rivaroxaban has recently been approved by the European Medicines Agency (but not the Food and Drug Administration) for secondary prevention after ACS. Several strategies have been developed to balance the potential benefit of antithrombotic therapy against the risk of bleeding complications, for example, radial access in coronary angiography or restricted use of combination therapy, and others are under investigation, such as discontinuation of aspirin. This overview summarizes the current status of antithrombotic therapy in ACS and describes strategies currently explored to optimize its benefit/risk ratio.

Abstract 168: Effectiveness of Case-Based Education on Clinical Decision-Making in ACS

Introduction: Due to emerging clinical evidence and the availability of new therapies, professional societies continue to update guidelines that direct the management of patients with acute coronary syndromes (ACS). Evolving therapies and guidelines create clinical confusion. Confusion in ACS management has been self-identified by healthcare professionals (HCPs) as an area of clinical concern. Knowledge gaps were addressed by constructing a case-based educational intervention to improve physician’s ability to make appropriate evidence- and guidelines-based clinical decisions for patients with non-ST elevation myocardial infarction (NSTEMI).

Methods: The continuing medical education (CME) activity was developed as an online case-based text activity modeled after the interactive grand rounds approach where clinicians make clinical decisions about treatment for a patient. The activity targeted primary care physicians (PCPs) and cardiologists who manage patients experiencing an ACS and focused on application of guideline recommendations. The effects of education were assessed using a linked pre-/post-assessment study design that separated learners into 3 categories: improved (incorrect pre, correct post), reinforced (correct pre and post), and unaffected (incorrect post).

Results: 755 PCPs and 255 cardiologist completed both the pre- and post-assessment survey with a large overall effect size of 1.229 ( P =0.0001) and 0.808 ( P= 0.0005), respectively. PCPs Correct responses on post-assessment questions ranged between 18% and 164% higher after CME completion. A summary of the pre- compared with post-assessment scoring indicates the scoring distribution curve shifted to the right. While only 86 of 755 (11%) participants answered all 4 questions correctly on the pre-assessment, 451 (60%) answered them all correctly on the post-assessment. Between 17% and 53% of participants showed improvement in understanding individual learning concepts as demonstrated by selecting correct answers to case-based questions. Cardiologists Correct responses on post-assessment questions ranged between 3% and 134% higher after CME completion. A summary of the pre- compared with post-assessment scoring indicates the scoring distribution curve shifted to the right. While only 51 of 255 (20%) participants answered all 4 questions correctly on the pre-assessment, 176 (69%) answered them all correctly on the post-assessment. Between 6% and 55% of participants showed improvement in understanding individual learning concepts as demonstrated by selecting correct answers to case-based questions.

Conclusion: Online case-based CME activities modeled after the interactive grand rounds approach prompted changes in clinical knowledge, showing that when effectively constructed, online CME is an effective tool to improve clinical application of guidelines and clinical decision-making.

Predicting outcome in the COURAGE trial (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation): coronary anatomy versus ischemia

OBJECTIVES

The aim of this study was to determine the relative utility of anatomic and ischemic burden of coronary artery disease for predicting outcomes.

BACKGROUND

Both anatomic burden and ischemic burden of coronary artery disease determine patient prognosis and influence myocardial revascularization decisions. When both measures are available, their relative utility for prognostication and management choice is controversial.

METHODS

A total of 621 patients enrolled in the COURAGE (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation) trial with baseline quantitative nuclear single-photon emission computed tomography (SPECT) and quantitative coronary angiography were studied. Several multiple regression models were constructed to determine independent predictors of the endpoint of death, myocardial infarction (MI) (excluding periprocedural MI) and non-ST-segment elevation acute coronary syndromes (NSTE-ACS). Ischemic burden during stress SPECT, anatomic burden derived from angiography, left ventricular ejection fraction, and assignment to either optimal medical therapy (OMT) + percutaneous coronary intervention (PCI) or OMT alone were analyzed.

RESULTS

In nonadjusted and adjusted regression models, anatomic burden and left ventricular ejection fraction were consistent predictors of death, MI, and NSTE-ACS, whereas ischemic burden and treatment assignment were not. There was a marginal (p = 0.03) effect of the interaction term of anatomic and ischemic burden for the prediction of clinical outcome, but separately or in combination, neither anatomy nor ischemia interacted with therapeutic strategy to predict outcome.

CONCLUSIONS

In a cohort of patients treated with OMT, anatomic burden was a consistent predictor of death, MI, and NSTE-ACS, whereas ischemic burden was not. Importantly, neither determination, even in combination, identified a patient profile benefiting preferentially from an invasive therapeutic strategy. (Clinical Outcomes Utilizing Revascularization and Aggressive Drug Evaluation [COURAGE]; NCT00007657).

Bivalirudin: an anticoagulant option for percutaneous coronary intervention

Coronary artery thrombosis is usually triggered by platelet-rich thrombus superimposed on a spontaneously or mechanically disrupted atherosclerotic plaque. Thrombin and platelets both play a role in this process. Unfractionated heparin and aspirin have served as cornerstones in the prevention and treatment of intracoronary thrombus, but unfractionated heparin has several limitations that necessitate the use of adjunctive therapies, such as glycoprotein IIb/IIIa receptor inhibitors and clopidogrel, in order to reduce the risk of ischemic events. These combination therapies, however, typically increase the risk for bleeding complications, as well as the cost and complexity of treatment. Bivalirudin (Angiomax, The Medicines Company), a thrombin-specific anticoagulant, does not share heparin's limitations. Bivalirudin appears to provide clinical advantages over unfractionated heparin therapy in acute coronary syndrome patients and those undergoing percutaneous coronary intervention, without increasing cost or complexity of treatment for most patients.

Prognostic importance of coronary anatomy and left ventricular ejection fraction despite optimal therapy: assessment of residual risk in the Clinical Outcomes Utilizing Revascularization and Aggressive DruG Evaluation Trial

BACKGROUND

It is unknown if baseline angiographic findings can be used to estimate residual risk of patients with chronic stable angina treated with both optimal medical therapy (OMT) and protocol-assigned or symptom-driven percutaneous coronary intervention (PCI).

METHODS

Death, myocardial infarction (MI), and hospitalization for non-ST-segment elevation acute coronary syndrome were adjudicated in 2,275 COURAGE patients. The number of vessels diseased (VD) was defined as the number of major coronary arteries with ≥50% diameter stenosis. Proximal left anterior descending, either isolated or in combination with other disease, was also evaluated. Depressed left ventricular ejection fraction (LVEF) was defined as ≤50%. Cox regression analyses included these anatomical factors as well as interaction terms for initial treatment assignment (OMT or OMT + PCI).

RESULTS

Percutaneous coronary intervention and proximal left anterior descending did not influence any outcome. Death was predicted by low LVEF (hazard ratio [HR] 1.86, CI 1.34-2.59, P < .001) and VD (HR 1.45, CI 1.20-1.75, P < .001). Myocardial infarction and non-ST-segment elevation acute coronary syndrome were predicted only by VD (HR 1.53, CI 1.30-1.81 and HR 1.24, CI 1.06-1.44, P = .007, respectively).

CONCLUSIONS

In spite of OMT and irrespective of protocol-assigned or clinically driven PCI, LVEF and angiographic burden of disease at baseline retain prognostic power and reflect residual risk for secondary ischemic events.

Change in enrollment patterns, patient selection, and clinical outcomes with the availability of drug-eluting stents in the Bypass Angioplasty Revascularization Investigation 2 Diabetes trial

BACKGROUND

In the BARI 2D trial, patients with type 2 diabetes and stable coronary artery disease were randomized to prompt revascularization versus intensive medical therapy (IMT). This analysis sought to evaluate how the availability of drug-eluting stents (DESs) has changed practice and outcomes.

METHODS

In BARI 2D, 1,605 patients were in the percutaneous coronary intervention (PCI)-intended stratum. As DES became available midway through recruitment, we report clinical outcomes among patients who underwent IMT versus prompt PCI with bare-metal stents (BMSs) or DES up to 4 years.

RESULTS

In North America, after DES became available, selection for the PCI-intended stratum increased from 73% to 79% (P = .003). Fewer BMS than DES patients had total occlusions treated or underwent rotational atherectomy (5.6% vs 9.7%, P = .02, and 1.2% vs 3.7%, P < .01, respectively). Subsequent revascularization (IMT 39%, BMS 29%, DES 21%, P < .01) and target vessel revascularization (BMS 16.1% vs DES 9.6%, P = .03) were lower with DES. Angina at 2 years tended to be less common with DES (IMT 39%, BMS 37%, DES 29%, P = .04, for 3 groups, P = .07 for DES vs BMS). The composite of death, myocardial infarction, or stroke was IMT 16.0%, BMS 20.5%, DES 17.5%; P = .80.

CONCLUSIONS

When DES became available in North America, patients were more likely to be selected into the PCI-intended stratum. Compared with patients receiving BMS, those receiving DES tended to have less target vessel revascularization and angina.

False activation of the cardiac catheterization laboratory for primary PCI

OBJECTIVES

We sought to evaluate trends in door-to-balloon (D2B) times and false activation rates for the cardiac catheterization laboratory (CCL) in patients presenting to the emergency department (ED) with acute ST-elevation myocardial infarction (STEMI). In patients with STEMI, national efforts have focused on reducing D2B times for primary percutaneous coronary intervention (P-PCI). This emphasis on time-to-treatment may increase the rate of false CCL activations and unnecessary healthcare utilization.

STUDY DESIGN

Retrospective quality improvement chart review.

METHODS

We examined all emergent CCL activations for P-PCI between 2007 and 2011 at the University of Michigan Hospital. False activation was defined as emergent CCL activation when the patient did not require CCL care or emergent cardiology evaluation in the ED. Pre-hospital or ED false activation rates and mean D2B time were retrospectively determined by chart review.

RESULTS

The CCL was activated 717 times for suspected STEMI. The number of CCL activations increased from 96 in 2007 to 190 in 2011. False CCL activations accounted for 28% of all prehospital and 29% of all ED activations. The false activation rate increased from 15% of all cases in 2007 to 40% of all cases in 2011. The median D2B time decreased from 67 minutes in 2007 to 55 minutes in 2011.

CONCLUSIONS

Over a 5-year period with a strong emphasis on reducing D2B times, there has been an increased CCL false activation rate for P-PCI.