Contemporary Patterns of Discharge Aspirin Dosing After Acute Myocardial Infarction in the United States

Background—

Accumulated data suggest that low-dose aspirin after myocardial infarction (MI) may offer similar efficacy to higher dose aspirin with reduced risk of bleeding. Few data are available on contemporary aspirin dosing patterns after MI in the United States

Methods and Results—

Aspirin dosing from 221 199 patients with MI (40.2% ST-segment–elevation MI) from 525 US hospitals enrolled in the National Cardiovascular Data Registry’s (NCDR’s) Acute Coronary Treatment and Intervention Outcomes Network Registry-Get with the Guidelines were described, overall and in clinically relevant subgroups. High-dose aspirin was defined as 325 mg and low dose as 81 mg. Between January 2007 and March 2011, 60.9% of patients with acute MI were discharged on high-dose aspirin, 35.6% on low-dose aspirin, and 3.5% on other doses. High-dose aspirin was prescribed at discharge to 73.0% of patients treated with percutaneous coronary intervention and 44.6% of patients managed medically. Among 9075 patients discharged on aspirin, thienopyridine, and warfarin, 44.0% were prescribed high-dose aspirin. Patients with an in-hospital major bleeding event were also frequently discharged on high-dose aspirin (56.7%). A 25-fold variation in the proportion prescribed high-dose aspirin at discharge was observed across participating centers.

Conclusions—

Most US patients with MI continue to be discharged on high-dose aspirin. Although aspirin dosing after percutaneous coronary intervention largely reflected prevailing guidelines before 2012, high-dose aspirin was prescribed with similar frequency in medically managed patients and to those in categories expected to be at high risk for bleeding. Wide variability in the proportional use of high-dose aspirin across centers suggests significant influence from local practice habits and uncertainty about appropriate aspirin dosing.

Early clopidogrel versus prasugrel use among contemporary STEMI and NSTEMI patients in the US: insights from the National Cardiovascular Data Registry

Background

P2Y12 antagonist therapy improves outcomes in acute myocardial infarction (MI) patients. Novel agents in this class are now available in the US. We studied the introduction of prasugrel into contemporary MI practice to understand the appropriateness of its use and assess for changes in antiplatelet management practices.

Methods and Results

Using ACTION Registry‐GWTG (Get‐with‐the‐Guidelines), we evaluated patterns of P2Y12 antagonist use within 24 hours of admission in 100 228 ST elevation myocardial infarction (STEMI) and 158 492 Non‐ST elevation myocardial infarction (NSTEMI) patients at 548 hospitals between October 2009 and September 2012. Rates of early P2Y12 antagonist use were approximately 90% among STEMI and 57% among NSTEMI patients. From 2009 to 2012, prasugrel use increased significantly from 3% to 18% (5% to 30% in STEMI; 2% to 10% in NSTEMI; P for trend <0.001 for all). During the same period, we observed a decrease in use of early but not discharge P2Y12 antagonist among NSTEMI patients. Although contraindicated, 3.0% of patients with prior stroke received prasugrel. Prasugrel was used in 1.9% of patients ≥75 years and 4.5% of patients with weight <60 kg. In both STEMI and NSTEMI, prasugrel was most frequently used in patients at the lowest predicted risk for bleeding and mortality. Despite lack of supporting evidence, prasugrel was initiated before cardiac catheterization in 18% of NSTEMI patients.

Conclusions

With prasugrel as an antiplatelet treatment option, contemporary practice shows low uptake of prasugrel and delays in P2Y12 antagonist initiation among NSTEMI patients. We also note concerning evidence of inappropriate use of prasugrel, and inadequate targeting of this more potent therapy to maximize the benefit/risk ratio.

Patterns of long-term thienopyridine therapy and outcomes in patients with acute coronary syndrome treated with coronary stenting: Observations from the TIMI-38 Coronary Stent Registry

BACKGROUND

The optimal duration of dual antiplatelet therapy (DAPT) after acute coronary syndrome (ACS) is not known. Factors influencing DAPT duration are not well described.

HYPOTHESIS

We hypothesized that continued DAPT 12 months beyond ACS would be associated with patient factors such as stent type and that it may be associated with lower rates of ischemic events.

METHODS

The TIMI 38 Coronary Stent Registry (CSR) followed patients who completed the TRITON-TIMI 38 trial, received a stent, and were alive and event free. Continuation of DAPT was determined by the treating physician.

RESULTS

The CSR enrolled 2110 patients (1679>12 months from index ACS) and followed for a median of 2.1 additional years. DAPT was continued in 554 (26%) and was more likely to be continued in patients with drug-eluting stents (DES; 54%) and in North America. The rate of cardiovascular death, MI, or stroke was 2.35% per year, and 13 patients (0.6%) experienced Academic Research Consortium definite or probable ST. Recurrent ischemic events were similar between patients who continued thienopyridine therapy and those who stopped at registry entry (P = 0.74 for cardiovascular death/MI/stroke; P = 0.72 for definite or probable ST). After propensity score adjustment, there was no significant difference in cardiovascular death/MI/stroke (P = 0.55) or bleeding (P = 0.51) with prolonged DAPT.

CONCLUSIONS

Patients stabilized for a year after ACS and stenting have low rates of ST relative to overall cardiovascular events. The decision to continue DAPT maybe associated with stent type (DES vs bare-metal stent) and region.

Clinical features, use of evidence-based therapies, and cardiovascular outcomes among patients with chronic kidney disease following non-ST-elevation acute coronary syndrome

BACKGROUND

Chronic kidney disease (CKD) is associated with an increased risk of cardiovascular events following acute coronary syndrome (ACS). The underlying pathobiology and optimal treatments for this population continue to be evaluated.

HYPOTHESIS

Patients with CKD will receive fewer evidence-based therapies and experience high rates of adverse cardiovascular events in both the short- and long term.

METHODS

The MERLIN-TIMI 36 (Metabolic Efficiency With Ranolazine for Less Ischemia in Non-ST-Elevation Acute Coronary Syndromes-Thrombolysis in Myocardial Infarction 36) trial randomized non-ST-elevation ACS patients to ranolazine or placebo, with no exclusion for renal dysfunction (except dialysis). We conducted a prespecified analysis among 6543 patients based on the degree of CKD.

RESULTS

Patients with worse renal function were older with more comorbidities (P < 0.0001 for each). They were less likely to receive evidence-based cardiovascular medicines (P < 0.04 for each). Rates of an early invasive management strategy varied based on renal function; however, among patients with the highest TIMI risk scores, the rates of an early invasive management strategy were similar regardless of glomerular filtration rate (GFR) (Pinteraction = 0.005). Lower GFR was associated with increased rates of cardiovascular disease or myocardial infarction in the short and long term, even after adjustment (GFR <30 vs ≥90 mL/min/1.73 m(2) ; hazard ratio [HR]: 3.24 [95% confidence interval {CI}: 1.26-8.38] through 7 days and HR: 2.12 [95% CI: 1.33-3.39] through 1 year). The effect of ranolazine vs placebo on clinical outcomes was similar among those with and without CKD (Pinteraction = not significant).

CONCLUSIONS

Following ACS, patients with renal dysfunction had more cardiovascular risk factors but were less likely to receive evidence-based medical therapies. A strong graded, independent relationship between the degree of CKD and poor clinical outcomes was observed over time. Continued efforts to optimize ACS treatment strategies in patients with CKD are warranted.

Clinical implications and correlates of Q waves in patients with ST-elevation myocardial infarction treated with fibrinolysis: observations from the CLARITY-TIMI 28 trial

BACKGROUND

The relationships between Q waves that appear during the acute phase of ST-elevation myocardial infarction (STEMI), clinical characteristics, ST-segment resolution (STRes), and clopidogrel therapy in patients treated with fibrinolysis are not well described.

HYPOTHESIS

We hypothesized that Q waves would be associated with less successful reperfusion and increased cardiovascular events.

METHODS

In the CLARITY-TIMI 28 trial, 3491 STEMI patients treated with fibrinolysis were randomized to clopidogrel or placebo. Electrocardiograms were evaluated for STRes post-fibrinolysis and the presence of pathologic Q waves during the index hospitalization in 3322 patients.

RESULTS

Q waves were identified in 2045 patients (61.6%) prior to discharge and were associated with increased odds of congestive heart failure (CHF) (adjusted odds ratio [ORadj ]: 2.10, P = 0.002) or the composite of cardiovascular death/CHF at 30 days (ORadj : 2.08, P ≤ 0.001). Q waves were associated with lower odds of Thrombolysis in Myocardial Infarction [TIMI] flow grade 2 to 3 (ORadj : 0.78, P = 0.028), TIMI myocardial perfusion grade 3 (ORadj : 0.83, P = 0.029), and complete STRes at 90 minutes (ORadj : 0.80, P = 0.030). Patients with both a Q wave and incomplete STRes 90 minutes after fibrinolysis were at higher risk for cardiovascular death or CHF (11.1%) than patients with no Q wave and at least partial STRes (1.9%). Overall, clopidogrel tended to be equally or more effective in patients without Q waves compared to those with Q waves.

CONCLUSIONS

Among STEMI patients treated with fibrinolysis, evaluating for Q waves prior to discharge is a simple method of assessing for less successful reperfusion and an increased risk of adverse 30-day cardiovascular outcomes. The combination of Q waves and 90-minute STRes allows additional risk refinement.

Edoxaban versus warfarin in patients with atrial fibrillation

BACKGROUND

Edoxaban is a direct oral factor Xa inhibitor with proven antithrombotic effects. The long-term efficacy and safety of edoxaban as compared with warfarin in patients with atrial fibrillation is not known.

METHODS

We conducted a randomized, double-blind, double-dummy trial comparing two once-daily regimens of edoxaban with warfarin in 21,105 patients with moderate-to-high-risk atrial fibrillation (median follow-up, 2.8 years). The primary efficacy end point was stroke or systemic embolism. Each edoxaban regimen was tested for noninferiority to warfarin during the treatment period. The principal safety end point was major bleeding.

RESULTS

The annualized rate of the primary end point during treatment was 1.50% with warfarin (median time in the therapeutic range, 68.4%), as compared with 1.18% with high-dose edoxaban (hazard ratio, 0.79; 97.5% confidence interval [CI], 0.63 to 0.99; P<0.001 for noninferiority) and 1.61% with low-dose edoxaban (hazard ratio, 1.07; 97.5% CI, 0.87 to 1.31; P=0.005 for noninferiority). In the intention-to-treat analysis, there was a trend favoring high-dose edoxaban versus warfarin (hazard ratio, 0.87; 97.5% CI, 0.73 to 1.04; P=0.08) and an unfavorable trend with low-dose edoxaban versus warfarin (hazard ratio, 1.13; 97.5% CI, 0.96 to 1.34; P=0.10). The annualized rate of major bleeding was 3.43% with warfarin versus 2.75% with high-dose edoxaban (hazard ratio, 0.80; 95% CI, 0.71 to 0.91; P<0.001) and 1.61% with low-dose edoxaban (hazard ratio, 0.47; 95% CI, 0.41 to 0.55; P<0.001). The corresponding annualized rates of death from cardiovascular causes were 3.17% versus 2.74% (hazard ratio, 0.86; 95% CI, 0.77 to 0.97; P=0.01), and 2.71% (hazard ratio, 0.85; 95% CI, 0.76 to 0.96; P=0.008), and the corresponding rates of the key secondary end point (a composite of stroke, systemic embolism, or death from cardiovascular causes) were 4.43% versus 3.85% (hazard ratio, 0.87; 95% CI, 0.78 to 0.96; P=0.005), and 4.23% (hazard ratio, 0.95; 95% CI, 0.86 to 1.05; P=0.32).

CONCLUSIONS

Both once-daily regimens of edoxaban were noninferior to warfarin with respect to the prevention of stroke or systemic embolism and were associated with significantly lower rates of bleeding and death from cardiovascular causes. (Funded by Daiichi Sankyo Pharma Development; ENGAGE AF-TIMI 48 ClinicalTrials.gov number, NCT00781391.).

Discharge aspirin dose and clinical outcomes in patients with acute coronary syndromes treated with prasugrel versus clopidogrel: an analysis from the TRITON-TIMI 38 study (trial to assess improvement in therapeutic outcomes by optimizing platelet inhibition with prasugrel-thrombolysis in myocardial infarction 38)

OBJECTIVES

The goal of this study was to determine whether there is a relationship between aspirin dose and the potent antiplatelet agent prasugrel in the TRITON-TIMI 38 (Trial to Assess Improvement in Therapeutic Outcomes by Optimizing Platelet Inhibition With Prasugrel-Thrombolysis In Myocardial Infarction 38) study.

BACKGROUND

Optimal aspirin dosing after acute coronary syndromes remains uncertain. Previous studies have raised questions regarding an interaction between high-dose aspirin and the potent antiplatelet agent ticagrelor.

METHODS

In TRITON-TIMI 38, we classified 12,674 patients into low-dose (<150 mg) or high-dose (≥150 mg) aspirin groups based on discharge dose. We identified independent correlates of dose selection and studied the impact of aspirin dose on the clinical effects of prasugrel.

RESULTS

There was significant geographical variation in aspirin dosing, with North American patients receiving high-dose aspirin more frequently than other countries (66% vs. 28%; p < 0.001). Clinical factors correlating with high-dose aspirin included previous percutaneous coronary intervention and use of aspirin before randomization. Characteristics associated with the use of low-dose aspirin included age ≥75 years, white race, and use of bivalirudin or a glycoprotein IIb/IIIa inhibitor during coronary intervention. Regardless of low- or high-dose aspirin use, prasugrel had lower rates of the primary efficacy endpoint (cardiovascular death, myocardial infarction, or stroke [CVD/MI/stroke]) (hazard ratio [HR]CVD/MI/stroke = 0.78 [95% confidence interval (CI) 0.64 to 0.95] and HRCVD/MI/stroke = 0.87 [95% CI 0.69 to 1.10], respectively; p value for interaction = 0.48) and higher rates of the primary safety endpoint (HR TIMI major bleeding = 1.40 [95% CI 0.81 to 2.42] and TIMImajor bleeding = 1.30 [95% CI 0.63 to 2.68], respectively; p value for interaction = 0.84) compared with clopidogrel.

CONCLUSIONS

In TRITON-TIMI 38, the safety and efficacy outcomes of prasugrel compared with those of clopidogrel were directionally consistent regardless of aspirin dose, although only the primary efficacy endpoint achieved statistical significance. There was no clinically meaningful interaction of aspirin with prasugrel, suggesting that previous observations with potent antiplatelet agents indicating differential results are not universal. (A Comparison of Prasugrel [CS-747] and Clopidogrel in Acute Coronary Syndrome Subjects Who Are to Undergo Percutaneous Coronary Intervention; NCT00097591).

Saxagliptin and cardiovascular outcomes in patients with type 2 diabetes mellitus

BACKGROUND

The cardiovascular safety and efficacy of many current antihyperglycemic agents, including saxagliptin, a dipeptidyl peptidase 4 (DPP-4) inhibitor, are unclear.

METHODS

We randomly assigned 16,492 patients with type 2 diabetes who had a history of, or were at risk for, cardiovascular events to receive saxagliptin or placebo and followed them for a median of 2.1 years. Physicians were permitted to adjust other medications, including antihyperglycemic agents. The primary end point was a composite of cardiovascular death, myocardial infarction, or ischemic stroke.

RESULTS

A primary end-point event occurred in 613 patients in the saxagliptin group and in 609 patients in the placebo group (7.3% and 7.2%, respectively, according to 2-year Kaplan-Meier estimates; hazard ratio with saxagliptin, 1.00; 95% confidence interval [CI], 0.89 to 1.12; P=0.99 for superiority; P<0.001 for noninferiority); the results were similar in the "on-treatment" analysis (hazard ratio, 1.03; 95% CI, 0.91 to 1.17). The major secondary end point of a composite of cardiovascular death, myocardial infarction, stroke, hospitalization for unstable angina, coronary revascularization, or heart failure occurred in 1059 patients in the saxagliptin group and in 1034 patients in the placebo group (12.8% and 12.4%, respectively, according to 2-year Kaplan-Meier estimates; hazard ratio, 1.02; 95% CI, 0.94 to 1.11; P=0.66). More patients in the saxagliptin group than in the placebo group were hospitalized for heart failure (3.5% vs. 2.8%; hazard ratio, 1.27; 95% CI, 1.07 to 1.51; P=0.007). Rates of adjudicated cases of acute and chronic pancreatitis were similar in the two groups (acute pancreatitis, 0.3% in the saxagliptin group and 0.2% in the placebo group; chronic pancreatitis, <0.1% and 0.1% in the two groups, respectively).

CONCLUSIONS

DPP-4 inhibition with saxagliptin did not increase or decrease the rate of ischemic events, though the rate of hospitalization for heart failure was increased. Although saxagliptin improves glycemic control, other approaches are necessary to reduce cardiovascular risk in patients with diabetes. (Funded by AstraZeneca and Bristol-Myers Squibb; SAVOR-TIMI 53 ClinicalTrials.gov number, NCT01107886.).

Circadian variation of stent thrombosis and the effect of more robust platelet inhibition: a post hoc analysis of the TRITON-TIMI 38 trial

BACKGROUND

The well-described morning peak in the onset of acute coronary syndromes has been partly attributed to increased platelet activity upon arising. It has been suggested that stent thrombosis (ST) exhibits a similar pattern. We assessed whether a diurnal variation in ST occurs, and whether more robust antiplatelet therapy with prasugrel (vs clopidogrel) can attenuate a morning excess.

METHODS AND MATERIALS

Patients from the Trial to Assess Improvement in Therapeutic Outcomes by Optimizing Platelet Inhibition with Prasugrel-Thrombolysis in Myocardial Infarction (TRITON-TIMI) 38 trial (N = 13 608) with adjudicated ST classified per the Academic Research Consortium definitions of definite (N = 135) and probable (N = 27) were grouped into prespecified 8-hour intervals by time of onset: early (6 am-2 pm), late-day (2 pm-10 pm), and overnight (10 pm-6 am). We compared the rates per 1000 patients of ST across time intervals and stratified by treatment and stent type.

RESULTS

A diurnal variation in definite/probable ST was observed with rates of 6.5, 3.7, and 2.1 for early, late-day, and overnight intervals, respectively (P < .001), per 1000 patients treated. A sensitivity analysis excluding periprocedural acute-ST (<24 hours after index percutaneous coronary intervention [PCI]) resulted in similar findings (5.2, 2.5, and 1.8 per 1000, P < .001). The circadian variation in ST was observed in patients on clopidogrel (9.7, 4.8, and 3.1 per 1000, P < .001) with the highest rate of ST early in the day. Patients on prasugrel also demonstrated a circadian variation with particularly low rates of overnight ST (3.4, 3.0, and 1.1 per 1000, P = .020).

CONCLUSIONS

In TRITON-TIMI 38 trial, the timing of ST exhibited a significant diurnal variation similar to that seen with onset of other acute coronary syndromes. ST occurred less frequently among patients randomized to prasugrel compared to clopidogrel with the greatest absolute reduction (6.2 per 1000 patients) in events earlier in the day when platelet activity is known to be highest.

Anticoagulation with otamixaban and ischemic events in non-ST-segment elevation acute coronary syndromes: the TAO randomized clinical trial

IMPORTANCE

The optimal anticoagulant for patients with non-ST-segment elevation acute coronary syndromes (NSTE-ACS) managed with an invasive strategy remains controversial.

OBJECTIVE

To compare the clinical efficacy and safety of otamixaban, a novel intravenous direct factor Xa inhibitor, with that of unfractionated heparin plus downstream eptifibatide in patients with NSTE-ACS undergoing a planned early invasive strategy.

DESIGN, SETTING, AND PARTICIPANTS

Randomized, double-blind, active-controlled superiority trial that enrolled 13,229 patients with NSTE-ACS and a planned early invasive strategy, at 568 active sites in 55 countries and conducted between April 2010 and February 2013. A planned interim analysis was conducted for otamixaban dose selection.

INTERVENTIONS

Eligible participants were randomized to otamixaban (bolus and infusion, at 1 of 2 doses) or unfractionated heparin plus, at the time of percutaneous coronary intervention, eptifibatide. The otamixaban dose selected at interim analysis was an intravenous bolus of 0.080 mg/kg followed by an infusion of 0.140 mg/kg per hour.

MAIN OUTCOMES AND MEASURES

The primary efficacy outcome was the composite of all-cause death or new myocardial infarction through day 7.

RESULTS

Rates of the primary efficacy outcome were 5.5% (279 of 5105 patients) randomized to receive otamixaban and 5.7% (310 of 5466 patients) randomized to receive unfractionated heparin plus eptifibatide (adjusted relative risk, 0.99 [95% CI, 0.85-1.16]; P = .93). There were no differences for the secondary end points, including procedural thrombotic complications. The primary safety outcome of Thrombosis in Myocardial Infarction major or minor bleeding through day 7 was increased by otamixaban (3.1% vs 1.5%; relative risk, 2.13 [95% CI, 1.63-2.78]; P < .001). Results were consistent across prespecified subgroups.

CONCLUSIONS AND RELEVANCE

Otamixaban did not reduce the rate of ischemic events relative to unfractionated heparin plus eptifibatide but did increase bleeding. These findings do not support the use of otamixaban for patients with NSTE-ACS undergoing planned early percutaneous coronary intervention.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01076764.

Prasugrel versus clopidogrel for patients with unstable angina or non-ST-segment elevation myocardial infarction with or without angiography: a secondary, prespecified analysis of the TRILOGY ACS trial

BACKGROUND

Treatment with prasugrel and aspirin improves outcomes compared with clopidogrel and aspirin for patients with acute coronary syndrome who have had angiography and percutaneous coronary intervention; however, no clear benefit has been shown for patients managed first with drugs only. We assessed outcomes from the TRILOGY ACS trial based on whether or not patients had coronary angiography before treatment was chosen.

METHODS

TRILOGY ACS (ClinicalTrials.gov number NCT00699998) was a randomised controlled trial, done at more than 800 sites worldwide. Patients with non-ST-elevation acute coronary syndrome who were selected for management without [corrected] revascularisation were randomly assigned to clopidogrel or prasugrel.The primary endpoint was cardiovascular death, myocardial infarction, or stroke at 30 months. In the present analysis we assessed differences in the primary endpoint by angiography status and whether the effects of treatment on the primary endpoint differed between patients who had angiography before enrolment and those who had not.

FINDINGS

7243 patients younger than 75 years were included in the TRILOGY ACS primary analysis. 3085 (43%) had angiography at baseline, 4158 (57%) had not. Fewer patients who had angiography reached the primary endpoint at 30 months compared with those who did not have angiography, according to Kaplan-Meier analysis (281/3085 [12·8%] vs 480/4158 [16·5%], adjusted hazard ratio [HR] 0·63, 95% CI 0·53-0·75; p<0·0001). The proportion of patients who reached the primary endpoint was lower in the prasugrel group than in the clopidogrel group for those who had angiography (122/1524 [10·7%] vs 159/1561 [14·9%], HR 0·77, 95% CI 0·61-0·98; p=0·032) but did not differ between groups in patients who did not have angiography (242/2096 [16·3%] vs 238/2062 [16·7%], HR 1·01, 0·84-1·20; p=0·94; pinteraction=0·08). Overall, TIMI major bleeding and GUSTO severe bleeding were rare. Bleeding outcomes tended to be higher with prasugrel but did not differ significantly between treatment groups in either angiography cohort.

INTERPRETATION

Among patients who had angiography who took prasugrel there were fewer cardiovascular deaths, myocardial infarctions, or strokes than in those who took clopidogrel. This result needs to be corroborated, but it is consistent with previous trials of more versus less intensive antiplatelet treatment. When angiography is done for acute coronary syndrome and anatomic coronary disease confirmed, the benefits and risks of intensive antiplatelet treatment exist whether the patient is treated with drugs or percutaneous coronary intervention.

FUNDING

Daiichi Sankyo, Eli Lilly.

Comparison of the efficacy and safety of two rivaroxaban doses in acute coronary syndrome (from ATLAS ACS 2-TIMI 51)

The dosing of anticoagulants is critical when balancing efficacy and safety. The Anti-Xa Therapy to Lower Cardiovascular Events in Addition to Aspirin With/Without Thienopyridine Therapy in Subjects With Acute Coronary Syndrome 2-Thrombolysis In Myocardial Infarction 51 (ATLAS ACS 2-TIMI 51) trial was designed to evaluate 2 low doses of rivaroxaban compared with placebo in patients with recent acute coronary syndromes being treated with antiplatelet therapies. Because the 2 doses significantly reduced the primary efficacy end point, a further comparison of the 2 treatment strategies was deemed important. In total, 15,526 patients were randomized to twice-daily rivaroxaban 2.5 mg, rivaroxaban 5 mg, or placebo. Comparing the 2 active doses, there were no significant differences between 2.5 and 5 mg for the primary efficacy end point of cardiovascular death, myocardial infarction, or stroke (9.1% vs 8.8%, p = 0.89), myocardial infarction (6.1% vs 4.9%, p = 0.23), or stent thrombosis (2.2% vs 2.3%, p = 0.59). However, there was a divergence in cardiovascular death, which included ischemic and hemorrhagic events, with the 2.5-mg dose resulting in lower rates than the 5-mg dose (2.7% vs 4.0%, p = 0.009). Notably, with 2.5 versus 5 mg, there were fewer study drug discontinuations (p = 0.004) and fewer non-coronary artery bypass grafting TIMI major or minor bleeds (p = 0.021) and fatal bleeds (p = 0.044). Of the patients who died, 8 in the 2.5-mg group and 20 in the 5-mg group experienced non-coronary artery bypass grafting TIMI major or minor bleeding events before death. In conclusion, the 2 doses of rivaroxaban reduced cardiovascular events in patients with recent acute coronary syndromes treated with antiplatelet therapies; however, the 2.5-mg dose was associated with lower mortality and fewer bleeding complications than the 5-mg dose. Thus, the addition of rivaroxaban 2.5 mg twice daily offers a more favorable balance of efficacy and safety in patients with recent acute coronary syndromes.

Sex differences in the effectiveness of early coronary computed tomographic angiography compared with standard emergency department evaluation for acute chest pain: the rule-out myocardial infarction with Computer-Assisted Tomography (ROMICAT)-II Trial

BACKGROUND

We evaluate sex-based differences in the effectiveness of early cardiac computed tomographic angiography (CCTA) and standard emergency department (ED) evaluation in patients with acute chest pain.

METHODS AND RESULTS

In the Rule-Out Myocardial Infarction With Computer-Assisted Tomography (ROMICAT)-II multicenter, controlled trial, we randomized 1000 patients (47% women) 40 to 74 years of age with symptoms suggestive of acute coronary syndrome to an early CCTA or standard ED evaluation. In this prespecified analysis, women in the CCTA arm had a greater reduction in length of stay, lower hospital admission rates, and lesser increased cumulative radiation dose than men in a comparison of ED strategies (P for interaction ≤0.02). Although women had lower acute coronary syndrome rates than men (3% versus 12%; P<0.0001), sex differences in length of stay persisted after adjustment for baseline differences, including acute coronary syndrome rate (P for interaction <0.03). Length of stay was similar between sexes with normal CCTA findings (P=0.11). There was no missed acute coronary syndrome for either sex. No difference was observed in major adverse cardiac events between sexes and ED strategies (P for interaction =0.39). Women had more normal CCTA examinations than men (58% versus 37%; P<0.0001), less obstructive coronary disease by CCTA (5% versus 17%; P=0.0001), but similar normalcy rates for functional testing (P=0.65). Men in the CCTA arm had the highest rate of invasive coronary angiography (18%), whereas women had comparable low 5% rates regardless of ED strategy.

CONCLUSIONS

This trial provides data supporting an early CCTA strategy as an attractive option in women presenting to the ED with symptoms suggestive of acute coronary syndrome. The findings may be explained by lower CAD prevalence and severity in women than men.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT01084239.

Association between natriuretic peptides and mortality among patients admitted with myocardial infarction: a report from the ACTION Registry(R)-GWTG™

BACKGROUND

Patients with increased blood concentrations of natriuretic peptides (NPs) have poor cardiovascular outcomes after myocardial infarction (MI). The objectives of this analysis were to evaluate the utilization and the prognostic value of NP in a large, real-world MI cohort.

METHODS

Data from 41 683 patients with non-ST-segment elevation MI (NSTEMI) and 27 860 patients with ST-segment elevation MI (STEMI) at 309 US hospitals were collected as part of the ACTION Registry®-GWTG™ (Acute Coronary Treatment and Intervention Outcomes Network Registry-Get with the Guidelines) (AR-G) between July 2008 and September 2009.

RESULTS

B-type natriuretic peptide (BNP) or N-terminal pro-BNP (NT-proBNP) was measured in 19 528 (47%) of NSTEMI and 9220 (33%) of STEMI patients. Patients in whom NPs were measured were older and had more comorbidities, including prior heart failure or MI. There was a stepwise increase in the risk of in-hospital mortality with increasing BNP quartiles for both NSTEMI (1.3% vs 3.2% vs 5.8% vs 11.1%) and STEMI (1.9% vs 3.9% vs 8.2% vs 17.9%). The addition of BNP to the AR-G clinical model improved the C statistic from 0.796 to 0.807 (P < 0.001) for NSTEMI and from 0.848 to 0.855 (P = 0.003) for STEMI. The relationship between NPs and mortality was similar in patients without a history of heart failure or cardiogenic shock on presentation and in patients with preserved left ventricular function.

CONCLUSIONS

NPs are measured in almost 50% of patients in the US admitted with MI and appear to be used in patients with more comorbidities. Higher NP concentrations were strongly and independently associated with in-hospital mortality in the almost 30 000 patients in whom NPs were assessed, including patients without heart failure.

Relation between time of symptom onset of ST-segment elevation myocardial infarction and patient baseline characteristics: from the National Cardiovascular Data Registry

BACKGROUND

The presence of a morning excess of ST-segment elevation myocardial infarction (STEMI) has been observed. The relation between patient characteristics and timing of STEMI may provide insight into the biological processes responsible for this phenomenon.

HYPOTHESIS

Patient baseline characteristics will vary with timing of STEMI.

METHODS

We performed an analysis using a large national registry of unselected patients with STEMI (N=45,218). Patients were categorized by time of symptom onset: early (6 am-2 pm), late day (2 pm-10 pm), and overnight (10 pm-6 am) then evaluated for variations in characteristics.

RESULTS

A circadian variation in the timing of symptom onset of STEMI was observed (early 41%, late day 32%, and overnight 26%, P<0.001). Circadian variations in factors known to alter timing of events were seen, including lower rates of home β-blocker use, smoking, and diabetes, with early onset of STEMI symptoms. In addition, patients in the 6 am to 2 pm subgroup were more likely older, white race, and male, with higher rates of home aspirin use and lower rates of obesity. Higher rates of coexisting cardiovascular disease, including prior heart failure, 3-vessel coronary artery disease, and depressed left ventricular ejection fraction, were observed in the overnight group. More robust antiplatelet therapy with home clopidogrel use was not associated with a change in the timing of events.

CONCLUSIONS

A morning excess of STEMI continues to exist and represents a potential target for preventative strategies. Patient baseline characteristics vary with the onset of STEMI and may reflect a physiologic relationship between these factors and the timing of events.

Design and rationale of the treatment of acute coronary syndromes with otamixaban trial: a double-blind triple-dummy 2-stage randomized trial comparing otamixaban to unfractionated heparin and eptifibatide in non-ST-segment elevation acute coronary syndromes with a planned early invasive strategy

BACKGROUND

Otamixaban is a synthetic intravenous direct factor Xa inhibitor, with rapid onset/offset, linear kinetics, and no significant renal elimination. A phase II trial in acute coronary syndromes (ACS) showed a marked reduction in the combined end point of death or myocardial infarction (MI) and similar bleeding rates with otamixaban at midrange doses, compared with unfractionated heparin (UFH) and eptifibatide.

DESIGN

The TAO trial is a phase III, randomized, double-blind, triple-dummy controlled trial testing the efficacy of otamixaban over UFH plus eptifibatide in patients with non-ST-segment elevation ACS to be treated with dual oral antiplatelet therapy and an invasive strategy. Approximately 13,220 patients in 55 countries will be randomized (1:1:1 ratio) to receive UFH plus downstream eptifibatide (started pre-percutaneous coronary intervention and continued per label) or otamixaban (0.08 mg/kg intravenous bolus at randomization then 0.100 or 0.140 mg/kg per hour intravenous infusion). An interim analysis was performed after ≥1,969 patients per arm completed 7 days of follow-up and the Data Monitoring Committee selected 1 otamixaban dose (blinded to investigators) to be carried forward using a prespecified algorithm. The primary efficacy outcome is the composite of all-cause mortality or new MI through day 7. The primary safety outcome is thrombolysis in MI major or minor bleeding through day 7. Secondary outcomes include all-cause mortality, recurrent ischemia/infarction resulting in prolonged/recurrent hospitalization, periprocedural angiographic complications, and pharmacokinetic data in 6,000 patients.

CONCLUSIONS

The TAO trial will assess the clinical efficacy and safety of otamixaban in non-ST-segment elevation ACS with planned invasive strategy.

Hospital length of stay in patients with non-ST-segment elevation myocardial infarction

PURPOSE

Substantial heterogeneity in hospital length of stay exists among patients admitted with non-ST-segment elevation myocardial infarction. Furthermore, little is known about the factors that impact length of stay.

METHODS

We examined 39,107 non-ST-segment elevation myocardial infarction patients admitted to 351 Acute Coronary Treatment Intervention Outcomes Network Registry-Get With The Guidelines hospitals from January 1, 2007-March 31, 2009 who underwent cardiac catheterization and survived to discharge. Length of stay was categorized into 4 groups (≤2, 3-4, 5-7, and ≥8 days), where prolonged length of stay was defined as >4 days.

RESULTS

The overall median (25(th), 75(th)) length of stay was 3 (2, 5) days. Patients with a length of stay of >2 days were older with more comorbidities, but were less likely to receive evidence-based therapies or percutaneous coronary intervention. Among the factors associated with prolonged length of stay >4 days were delay to cardiac catheterization >48 hours, heart failure or shock on admission, female sex, insurance type, and admission to the hospital on a Friday afternoon or evening. Hospital characteristics such as academic versus nonacademic or urban versus rural setting, were not associated with prolonged length of stay.

CONCLUSION

Patients with longer length of stay have more comorbidities and in-hospital complications, yet paradoxically, are less often treated with evidence-based medications and are less likely to receive percutaneous coronary intervention. Hospital admission on a Friday afternoon or evening and delays to catheterization appear to significantly impact length of stay. A better understanding of factors associated with length of stay in patients with non-ST-segment elevation myocardial infarction is needed to promote safe and early discharge in an era of increasingly restrictive health care resources.

Scirica B. Risk of Heart Failure Complication During Hospitalization for Acute Myocardial Infarction in a Contemporary Population

Background—

Patients with acute myocardial infarction (MI) complicated by heart failure (HF) are subject to higher mortality during the index hospitalization. Early risk prediction and intervention may help prevent HF-related morbidity and mortality.

Methods and Results—

We examined 77 675 ST-elevation MI and 110 128 non-ST-elevation patients with MI without cardiogenic shock or HF at presentation treated at 609 hospitals in Acute Coronary Treatment and Intervention Outcomes Network Registry (ACTION) Registry-Get With The Guidelines between January 1, 2007, and March 31, 2011. Logistic regression identified patient characteristics associated with development of in-hospital HF. Overall, 3.8% of patients with MI developed in-hospital HF, which was associated with higher mortality in both ST-elevation MI and non-ST elevation MI. In multivariable logistic regression, left ventricular ejection fraction ≤30%, prior HF, diabetes mellitus, female sex, ST-elevation MI, and hypertension (all P <0.005) were independently associated with in-hospital HF. Patients who developed HF during non-ST-elevation MI were more likely to be medically managed without catheterization (30% versus 13% with HF, P <0.0001) or had longer delays to surgical or percutaneous revascularization. Patients with ST-elevation MI and HF were less likely to receive primary percutaneous coronary revascularization (84% versus 79% with HF, P <0.0001), and more likely to receive thrombolytic therapy (14% versus 11%; P =0.0001).

Conclusions—

Patients with MI who develop HF during hospitalization have a higher risk clinical profile and greater mortality, but may be less likely to receive revascularization in a timely fashion. Targeting these highest risk patients may improve outcome post-MI.

Coronary CT angiography versus standard evaluation in acute chest pain

BACKGROUND

It is unclear whether an evaluation incorporating coronary computed tomographic angiography (CCTA) is more effective than standard evaluation in the emergency department in patients with symptoms suggestive of acute coronary syndromes.

METHODS

In this multicenter trial, we randomly assigned patients 40 to 74 years of age with symptoms suggestive of acute coronary syndromes but without ischemic electrocardiographic changes or an initial positive troponin test to early CCTA or to standard evaluation in the emergency department on weekdays during daylight hours between April 2010 and January 2012. The primary end point was length of stay in the hospital. Secondary end points included rates of discharge from the emergency department, major adverse cardiovascular events at 28 days, and cumulative costs. Safety end points were undetected acute coronary syndromes.

RESULTS

The rate of acute coronary syndromes among 1000 patients with a mean (±SD) age of 54±8 years (47% women) was 8%. After early CCTA, as compared with standard evaluation, the mean length of stay in the hospital was reduced by 7.6 hours (P<0.001) and more patients were discharged directly from the emergency department (47% vs. 12%, P<0.001). There were no undetected acute coronary syndromes and no significant differences in major adverse cardiovascular events at 28 days. After CCTA, there was more downstream testing and higher radiation exposure. The cumulative mean cost of care was similar in the CCTA group and the standard-evaluation group ($4,289 and $4,060, respectively; P=0.65).

CONCLUSIONS

In patients in the emergency department with symptoms suggestive of acute coronary syndromes, incorporating CCTA into a triage strategy improved the efficiency of clinical decision making, as compared with a standard evaluation in the emergency department, but it resulted in an increase in downstream testing and radiation exposure with no decrease in the overall costs of care. (Funded by the National Heart, Lung, and Blood Institute; ROMICAT-II ClinicalTrials.gov number, NCT01084239.).

Clopidogrel Use and Hospital Quality in Medically Managed Patients With Non–ST-Segment–Elevation Myocardial Infarction

Background—

Clopidogrel prescription is a class I guideline recommendation for medically managed patients with non–ST-segment–elevation myocardial infarction (NSTEMI). However, clopidogrel has historically been underused in this population. We evaluated contemporary rates of its use and evaluated associated factors, with a particular focus on hospital quality of myocardial infarction (MI) care.

Methods and Results—

We examined clopidogrel prescription rates among 23 186 patients with NSTEMI discharged from 382 US hospitals between October 2009 and March 2011. Associations between clopidogrel prescription and various patient and hospital factors, including hospital quality of MI care, were determined with regression modeling. Of the sample, 54.9% of eligible patients with NSTEMI received clopidogrel prescription at hospital discharge. Variation in rate by hospital was large, ranging from 22% to 97%. A variety of patient and hospital factors were associated with clopidogrel prescription. Hospital quality of MI care demonstrated modest association with clopidogrel prescription (odds ratio, 0.68; 95% CI, 0.54–0.85) between the lowest and highest hospital quality quartile) and accounted for 5.7% of the variation in prescription rates.

Conclusions—

Clopidogrel prescription is significantly underused in the medically managed NSTEMI population and demonstrates wide variability by hospital. Although hospital quality of MI care is associated with its use, the findings suggest that it only has a modest effect. Therefore, efforts to improve clopidogrel use likely will require measures beyond improving the overall hospital quality of MI care.