Low Risk For Acute Coronary Syndrome Research Articles

Outcomes of non-invasive diagnostic modalities for the detection of coronary artery disease: network meta-analysis of diagnostic randomised controlled trials

ObjectiveTo evaluate differences in downstream testing, coronary revascularisation, and clinical outcomes following non-invasive diagnostic modalities used to detect coronary artery disease.DesignSystematic review and network meta-analysis.Data sourcesMedline, Medline in process, Embase,...

Identification of coronary artery calcification can optimize risk stratification in patients with acute chest pain

BackgroundThe number of patients presenting to the emergency department (ED) with suspected acute coronary syndrome (ACS) is substantial. We tested whether identification of coronary artery calcium (CAC) can improve the negative predictive value (NPV) of clinical risk assessment for ACS in patients with acute chest pain. Methods and resultsWe included 826 consecutive patients (mean age: 53±11years; 42% female) without known coronary artery disease (CAD) or initially elevated serum biomarkers, whom underwent non-contrast CT, to assess the CAC score, and CT angiography (CTA), to detect coronary stenosis. We analyzed the diagnostic performance of CAC and the Thrombolysis In Myocardial Infarction (TIMI) risk score for our primary outcomes (ACS and obstructive CAD).No CAC was found in 54% (n=444) of all patients, 63% (n=524) had a TIMI score of 0 and 40% (n=328) had both. The prevalence of obstructive CAD was 16% for ≥50% stenosis and 8.7% for ≥70% stenosis. The incidence of ACS was 7.9%, (MI=11, UAP=54). The NPV of CAC=0 was 99.5% for ACS. The NPV of a combination of TIMI score=0 and no CAC was 89% for any CAD (any plaque or stenosis) and 99.7% for ≥50% stenosis. A 100% NPV was found for ≥70% stenosis and ACS, correctly identifying 328 (40%) patients. ConclusionsThe exclusion of CAC, in combination with clinical risk assessment, has high clinical value in patients with acute chest pain, as it identifies patients at low risk for ACS and obstructive CAD more accurately as compared to clinical risk assessment alone.

OBSERVED VERSUS PREDICTED MORTALITY IN PATIENTS WITH ACUTE CORONARY SYNDROMES AND LOW-RISK GRACE SCORES

Guidelines recommend that patients with low-risk acute coronary syndromes (ACS) can be monitored in chest pain units or in hospital telemetry wards; however, up to two-thirds of patients with ACS are admitted to coronary care units (CCU). The outcomes of patients with low-risk ACS admitted to CCUs have not been well described. We examined the observed versus predicted mortality rates in patients with low-risk ACS admitted to CCUs. We created a linked administrative database using a population-based cohort of hospitalized patients (n = 6232) with an ACS admitted to a CCU in the province of Alberta between November 1, 2014 and June 30, 2016. We examined the observed versus GRACE score predicted mortality rates amongst 1290 patients with low-risk ACS defined as a GRACE score ≤ 110. The secondary outcome was critical care restricted therapies. The predicted number of in-hospital deaths was 7 (0.5%), but no in-hospital deaths were observed. In the entire cohort, no in-hospital deaths were observed among patients with a GRACE score < 119 (Figure). Of the 1290 low-risk patients, 579 (45%) required critical care restricted intravenous therapies; but, this was almost exclusively intravenous nitroglycerin (578 patients). Only one patient required dopamine. A total of 10 (0.8%) required non-invasive mechanical ventilation; none required invasive mechanical ventilation. In a large cohort of patients with low-risk GRACE scores admitted to a CCU, no in-hospital mortality was observed. In addition, there was no need for need for advanced critical care therapies beyond intravenous nitroglycerin. These findings support the routine admission of low-risk ACS patients to low-intensity hospital telemetry wards when critical care restricted therapies are not required. Future initiatives designed to decrease unnecessary low-risk CCU admissions have the potential to reduce critical care capacity strain and hospital costs.

Gender, race and the presentation of acute coronary syndrome and serious cardiopulmonary diagnoses in ED patients with chest pain

ObjectiveTo assess the relationship between reported chest pain symptoms and a diagnosis of acute coronary syndrome (ACS) and serious cardiopulmonary diagnoses (SCPD) in black males, white males, black females and...

Risk classification of highly sensitive troponin I predict presence of vulnerable plaque assessed by dual source coronary computed tomography angiography.

Patients presenting to the emergency department with acute chest pain, negative conventional troponin and electrocardiogram require serial testing to rule out acute coronary syndrome (ACS). We studied the association of highly sensitive troponin (hsTn) I with vulnerable plaque features as detected by coronary dual source computed tomography angiography (DSCTA) and determined whether hsTnI at the time of presentation combined with early DSCTA could improve classification of patients as high-risk or low risk for ACS. We included 220 patients with acute chest pain, negative electrocardiogram and conventional troponin who underwent DSCTA and had hsTn I measured at the time of presentation. The patients were categorized as having hsTn I below the limit of detection (low risk), intermediate and above the 99th percentile (high risk). Readers assessed DSCTA qualitatively for the presence of significant CAD (≥50% stenosis), calcified and non-calcified coronary plaque, and vulnerable plaque features (positive remodeling, low CT attenuation plaque, napkin-ring sign, spotty calcium). The mean age of the population was 50.3 ± 8.2 years (43% women). ACS during the index hospitalization occurred in 36 (16.3%) patients (myocardial infarction n = 8, unstable angina pectoris n = 28). HsTn I was below the limit of detection, intermediate, and above 99th percentile in 39 (17.7%), 139 (86.9%), and 42 (19.1%) patients, respectively. Across the categories of low risk, intermediate and high risk of hsTn I, there was increase in prevalence of ≥50% stenosis (0, 11.5, and 61.9% of patients; p < 0.001), any plaque (35.9, 51.1, and 85.7% of patients; p < 0.001) and high-risk plaque (0, 36.0, and 85.7% of patients; p < 0.001). None of the patients in low risk HsTn I group had ACS. ACS occurred in 10.1% of the intermediate hsTn I group and in 52.3% of the patients with high risk hsTnI group. Severity of stenosis and presence of vunerable plaque as detected by DSCTA are associated with increasing levels of hsTn I. DSCTA at the time of presentation with the assessment for both stenosis and high-risk plaque improved the diagnostic accuracy for ACS in the intermediate hsTnI group patients.

NON-INVASIVE FUNCTIONAL AND ANATOMICAL DIAGNOSTIC TESTING FOR PATIENTS WITH LOW-RISK ACUTE CORONARY SYNDROMES: A NETWORK META-ANALYSIS OF DIAGNOSTIC RANDOMIZED CONTROLLED TRIALS

Background: The comparative effects of non-invasive imaging on management and clinical outcomes in low-risk acute coronary syndromes (ACS) patients remain unclear. Methods: We performed a random-effects network meta-analysis to obtain estimates of relative effectiveness of non-invasive diagnostic

Outcomes after coronary computed tomography angiography of patients at low to intermediate risk for acute coronary syndrome

Background: Coronary computed tomography angiography (CTA) has recently been shown to enjoy a high negative predictive value for ruling out coronary heart disease and risk stratifying patients with acute coronary syndrome (ACS). Hence, we assessed the 1-year outcome associated with a CTA-guided strategy in patients presenting to the emergency department with low to intermediate risk for ACS graded according to the GRACE score. Methods: In this case-series study, 77 consecutive patients (mean age = 49.7 ± 10.1 and 53.2% female) who presented to the emergency department with ischemic-type chest pain and low to intermediate risk for ACS were evaluated prospectively. The patients underwent coronary CTA after the measurement of troponin I. Those with nonobstructive plaques and mild stenoses ( 70% narrowing) underwent coronary angiography. The discharged patients were contacted and their medical records were reviewed to determine the rates of major adverse cardiovascular events (MACE)—comprising death, myocardial infarction, stroke, hospital admission, and revascularization. Results: A total of 89.6% of the patients were in the low-risk ACS group. There was no significant association between MACE and the subscales and the GRACE score (P > 0.05). There was no relationship between the GRACE score and the severity of coronary stenosis (P > 0.05) and the high-severity plaques (P > 0.05). However, the severity of stenoses in the proximal part of the left anterior descending artery (LAD) (P = 0.00), the mid part of the LAD (P = 0.004), and the first part of the obtuse marginal artery (P = 0.004) was associated with MACE. Furthermore, there were no relationships between MACE and the high-risk plaques and the risk factors (P > 0.05). Conclusions: CTA ruled out significant lesions and optimal treatment was accompanied by good prognoses in our patients. CTA may, therefore, be an optimal cost-benefit modality for the determination of the diagnosis and the therapeutic modality in patients at low to intermediate risk for ACS presenting to the emergency department.

What Is Shared Decision Making? (and What It Is Not).

Both the practice of medicine and the expectations of patients regarding their care are changing. A point of confluence is in the need for medicine to be more patient centered, and in the need for patients to be more involved in their care.1,2 This confluence is particularly pertinent when more than one reasonable approach is available to manage the patient's situation, and when those approaches differ in ways that matter to patients.3 In shared decision-making (SDM), clinicians and patients work together to understand the patient's situation and to determine how best to address it. Emergency medicine is not exempt from these trends. In this paper we seek to define SDM and its role in contemporary healthcare. Our goal is to set the stage for the active exploration of SDM in the care of patients in the emergency department. This article is protected by copyright. All rights reserved.

Low Risk Acute Coronary Syndrome—How High Is Low?

Low Risk Acute Coronary Syndrome—How High Is Low?

Association between the docosahexaenoic acid to arachidonic acid ratio and acute coronary syndrome: a multicenter observational study.

BackgroundA low eicosapentaenoic acid (EPA) to arachidonic acid (AA) ratio is a known risk for acute coronary syndrome (ACS). However, the association between the docosahexaenoic acid (DHA) to AA ratio and ACS remains unclear. This study aimed to assess the association between the DHA/AA ratio and ACS by patient characteristics.MethodsWe enrolled 1733 patients and evaluated the serum levels of polyunsaturated fatty acids in 5 cardiology departments in a metropolitan area of Japan. We assessed the relationship between the DHA/AA ratio (median cut-off value: 0.903) and ACS according to the following 10 subgroups: sex, age, diabetes mellitus, hypertension, dyslipidemia, smoking history, family history of ischemic heart disease, chronic kidney disease, obesity, and history of coronary revascularization.ResultsInteraction tests in the 10 subgroup analyses revealed a significant difference for adjusted log odds ratios between male and females (p = 0.01), and those with and without hypertension (p = 0.06). Especially in the subgroup based on sex difference, a high DHA/AA ratio was significantly associated with a low risk of ACS among men (adjusted odds ratio = 0.389; 95 % confidence interval: 0.211–0.716). In contrast, a reverse association was found among women, although this was not statistically significant (adjusted odds ratio = 3.820; 95 % confidence interval: 0.718–20.325).ConclusionsThe association between the DHA/AA ratio and ACS differed by clinical characteristic. Notably, patients with a low DHA/AA ratio had a higher risk of ACS than those with a high DHA/AA ratio, and this was significant for men in particular.

48. Can early 24 hours Holter monitoring predict obstructive coronary artery lesions in patients with low risk acute coronary syndrome?

Identification of patients at increased risk of death due to acute coronary syndrome (ACS) can add to risk stratification and guide the next step in the management of those patients. Altered HRV has been associated with adverse outcomes in heart disease, but this has not been established in patients with acute chest pain.This study aimed to create a non-invasive, economical and risk-free method in the clinical evaluation and diagnosis of significant CAD among patients with unstable angina.Twenty-four-hour Holter recordings of 100 patients with ACS were initiated within 24 hours of admission at the emergency department; stress ECG was done for all patients while coronary angiography was done only for patients with abnormal stress test. Time domain, frequency domain, and nonlinear HRV were examined.The mean SDNN was statistically significantly lower in patients with abnormal stress test, many time and frequency domain HRV parameters was statistically lower in patients with significant coronary arteries obstruction. HRV measured close to the ACS onset may assist in risk stratification. HRV parameters may provide additional, incremental prognostic information to established assessment guidelines and possible early intervention in those patients.

Effects of Ticagrelor Versus Clopidogrel in Troponin-Negative Patients With Low-Risk ACS Undergoing Ad Hoc PCI

BackgroundMany low-risk acute coronary syndrome (ACS) patients are not pre-treated with a P2Y12 receptor inhibitor, and percutaneous coronary interventions (PCIs) are often performed on an ad hoc basis in this population. Pharmacodynamic (PD) studies comparing ticagrelor versus clopidogrel in patients undergoing ad hoc PCI are lacking. ObjectivesThis study sought to assess PD effects of ticagrelor versus clopidogrel loading dose (LD) in the peri-procedural period among troponin-negative ACS patients undergoing ad hoc PCI. MethodsThis was a prospective, open-label, randomized, multicenter, parallel-group, phase IV PD study. One hundred P2Y12 inhibitor-naïve patients presenting with biomarker-negative ACS and undergoing ad hoc PCI, on a background of aspirin therapy, were randomized to receive either ticagrelor 180 mg LD or clopidogrel 600 mg LD. Platelet reactivity (P2Y12 reaction units [PRU]; VerifyNow assay) was measured at 5 time points: pre-LD, at 0.5, 2, and 8 h post-LD, and at end of PCI. The primary endpoint was PRU levels 2 h post-LD; secondary endpoints included PRU levels at all other time points and inhibition of platelet aggregation; an exploratory analysis evaluated rates of high on-treatment platelet reactivity (HPR) (PRU >208). ResultsAt 2 h, PRU levels were significantly lower with ticagrelor versus clopidogrel (98.4 ± 95.4 vs. 257.5 ± 74.5; p < 0.001; primary endpoint). PRU levels diverged as early as 0.5 h post-LD, with significant differences observed by the end of PCI (mean 0.6 h post-LD) and maintained up to 8 h post-LD. HPR rates were also significantly reduced with ticagrelor compared with clopidogrel at the end of PCI (p = 0.030), and at 2 h (p < 0.001) and 8 h (p < 0.001) after LD. ConclusionsIn low-risk ACS patients undergoing ad hoc PCI, ticagrelor LD provides more prompt and potent platelet inhibition, and lower HPR rates, compared with clopidogrel LD. (Ad Hoc Percutaneous Coronary Intervention Study in Acute Coronary Syndrome Patients: NCT01603082)

Safety and efficiency of outpatient versus emergency department-based coronary CT angiography for evaluation of patients with potential ischemic chest pain

BackgroundWhile coronary CT angiography (coronary CTA) may be comparable to standard care in diagnosing acute coronary syndrome (ACS) in emergency department (ED) chest pain patients, it has traditionally been obtained prior to ED discharge and a strategy of delayed outpatient coronary CTA following an ED visit has not been evaluated. ObjectiveTo investigate the safety of discharging stable ED patients and obtaining outpatient CCTA. MethodsAt two urban Canadian EDs, patients up to 65 years with chest pain but no findings indicating presence of ACS were further evaluated depending upon time of presentation: (1) ED-based coronary CTA during normal working hours, (2) or outpatient coronary CTA within 72 hours at other times. All data were collected prospectively. The primary outcome was the proportion of patients who had an outpatient coronary CTA ordered and had a predefined major adverse cardiac event (MACE) between ED discharge and outpatient CT; secondary outcome was the ED length of stay in both groups. ResultsFrom July 1, 2012 to June 30, 2014, we enrolled 521 consecutive patients: 350 with outpatient CT and 171 with ED-based CT. Demographics and risk factors were similar in both cohorts. No outpatient CT patients had a MACE prior to coronary CTA. (0.0%, 95% CI 0 to 0.9%) The median length of stay for ED-based evaluation was 6.6 hours (interquartile range 5.4 to 8.3 hours) while the outpatient group had a median length of stay of 7.0 hours (IQR 6.0 to 9.8 hours, n.s.). ConclusionsIn ED chest pain patients with a low risk of ACS, performing coronary CTA as an outpatient may be a safe strategy.

Cost Effectiveness of Antiplatelet and Antithrombotic Therapy in the Setting of Acute Coronary Syndrome: Current Perspective and Literature Review.

Acute coronary syndromes (ACS) are associated with high rates of morbidity and mortality. The advances of antiplatelet and anticoagulation therapy over several years time have resulted in improved in cardiac outcomes, but with increased health care costs. Multiple cost-effectiveness studies have been performed to evaluate the use of available antiplatelet agents and anticoagulation in the setting of both ST-segment elevation myocardial infarction (STEMI) and non-ST-segment elevation acute coronary syndrome (NSTE-ACS). Early on, the use of glycoprotein IIb/IIIa receptor inhibitors (GPIs) proved to be economically attractive in the management of ACS; however, the introduction of P2Y12 receptor antagonists limited their use to a bail out agents in complex interventions. Generic clopidogrel is probably still an economically attractive P2Y12 receptor antagonist choice, especially in low-risk ACS, while both ticagrelor and prasugrel present an economically attractive alternative option, especially in high-risk ACS and patients at risk for stent thrombosis. While enoxaparin presents an economically dominant alternative to heparin in NSTE-ACS, its role in STEMI in the contemporary era is unclear. During percutaneous coronary intervention (PCI), bivalirudin monotherapy was shown to be an economically dominant alternative to the combination of heparin and GPI in ACS. However, new studies may suggest that using heparin monotherapy may offer an attractive alternative. The comparative and cost effectiveness of different combinations of antiplatelet and antithrombotic therapy will be the focus of future expected clinical and economic assessments.

Can Early 24 Hours Holter Monitoring Predict Obstructive Coronary Artery Lesions in Patients with Low Risk Acute Coronary Syndrome?

Can Early 24 Hours Holter Monitoring Predict Obstructive Coronary Artery Lesions in Patients with Low Risk Acute Coronary Syndrome?

0043: Prognosis of patients admitted with chest pain in emergency department and discharged with low risk of acute coronary syndrome

Chest pain is a frequent cause of admission to the emergency department (ED). The diagnosis and medical care of acute coronary syndrome (ACS) with ST-segment elevation (ST+ ACS) are more standardized than non ST-segment elevation ACS (NST ACS). There is very few series on patients classified as low ACS-diagnosis probability. We aimed to assess the 1-year outcome of patients admitted for chest pain in ED and discharged with low risk of ACS. This restrospective study included all patients admitted in the ED of University Hospital Center of Limoges between January and March 2013 for chest pain, without ST-segment elevation and normal troponin level. Patients’ characteristics and initial diagnosis were collected in ED records. Final diagnosis was obtained by phone one year later, from general practitioners or alternatively directly from the patients themselves. Among the 244 patients studied, 38 (15.6%) were lost during follow-up. Mean age was 50±17 years, 58% being males. Among the 41% of cases in whom the initial diagnosis (i.e. ED discharge) was modified during follow-up, 9% (n=8) were diagnosed with coronary disease, and 38% (n=32) with panic attack. Major adverse cardiac events rate was 2.4% (n=5) in the whole population, and 60% of them were directly discharged to home. In the ED, the detection of a cardiovascular etiology of chest pain was accurate with good specificity (96%) but lower sensibility (61%). Of note, the rate of false negative patients was 8.5%. Low probability NST SCA diagnosis is complex in the ED and may frequently lead to erroneous diagnosis associated with therapeutic delay. Nevertheless, cardiac disorders are uncommonly misdiagnosed. A systematic, individualized and close monitoring after ED discharge is mandatory.

Efficacy of multi-detector coronary computed tomography angiography in comparison with exercise electrocardiogram in the triage of patients of low risk acute chest pain

ObjectivesTo compare the safety and diagnostic efficacy of coronary computed tomography angiography (CTA) with exercise electrocardiography (XECG) in triaging patients of low risk acute chest pain. BackgroundNoninvasive assessment of coronary stenosis by CTA may improve early and accurate triage of patients presenting with acute chest pain to the emergency department (ED). MethodsLow risk patients of possible acute coronary syndrome (ACS) were included in the study. The patients in CTA arm with significant stenosis (≥50%) underwent catheterization, while those with no or intermediate stenosis (<50%) were discharged from ED and followed up periodically for six months for major adverse cardiovascular events (MACE). The same protocol was applied for XECG arm. Outcomes included: safety and diagnostic efficacy. ResultsA total of 81 (41 CTA and 40 XECG) patients were enrolled. In this study CTA was observed to be 100% sensitive and 95.7% specific in diagnosing MACE in low risk patients of chest pain presenting to the ED, with a PPV of 94.7% and an NPV of 100%.The overall diagnostic efficacy was 97.6%. XECG was observed to be 72.7% sensitive and 96.6% specific in diagnosing MACE with a PPV of 88.9% and NPV of 90.3% in low risk chest pain patients presenting to the ED. The overall diagnostic accuracy was 90%. ConclusionCTA is an excellent diagnostic tool in ED patients with low risk of ACS, with minimum time delay as compared to XECG, and also is safe for triaging such patients.

Use of Observed Within-Person Variation of Cardiac Troponin in Emergency Department Patients for Determination of Biological Variation and Percentage and Absolute Reference Change Values

Many patients presenting to the emergency department (ED) for assessment of possible acute coronary syndrome (ACS) have low cardiac troponin concentrations that change very little on repeat blood draw. It is unclear if a lack of change in cardiac troponin concentration can be used to identify acutely presenting patients at low risk of ACS. We used the hs-cTnI assay from Abbott Diagnostics, which can detect cTnI in the blood of nearly all people. We identified a population of ED patients being assessed for ACS with repeat cTnI measurement who ultimately were proven to have no acute cardiac disease at the time of presentation. We used data from the repeat sampling to calculate total within-person CV (CV(T)) and, knowing the assay analytical CV (CV(A)), we could calculate within-person biological variation (CV(i)), reference change values (RCVs), and absolute RCV delta cTnI concentrations. We had data sets on 283 patients. Men and women had similar CV(i) values of approximately 14%, which was similar at all concentrations <40 ng/L. The biological variation was not dependent on the time interval between sample collections (t = 1.5-17 h). The absolute delta critical reference change value was similar no matter what the initial cTnI concentration was. More than 90% of subjects had a critical reference change value <5 ng/L, and 97% had values of <10 ng/L. With this hs-cTnI assay, delta cTnI seems to be a useful tool for rapidly identifying ED patients at low risk for possible ACS.

Relationship of Plasma Adiponectin Levels with Acute Coronary Syndromes and Coronary Lesion Severity in North Indian Population

Adiponectin is an adipocyte specific cytokine which, in contrast to other adipokines, has been described to have antiinflammatory, antithrombotic, and anti-atherogenic properties. This study evaluates the association between plasma adiponectin levels with acute coronary syndrome (ACS) and angiographic coronary lesion severity in Indian population. Ninety patients included in the study were divided in two groups in 1 : 1 ratio—patients admitted with a diagnosis of ACS and those without ACS. Adiponectin and other risk markers are measured in forty-five consecutive patients in each group undergoing coronary angiography. Patients without ACS were found to have higher adiponectin (16.47 ± 7.88 μg/mL) levels than patients with ACS (9.03 ± 3.13 μg/mL) (P < 0.001). In multiple regression analysis adjusted for all other risk markers, higher adiponectin levels remain positively associated with a lower risk of ACS (P value > 0.002). The greatest increase in risk for ACS was seen at adiponectin levels ≤12.20 μg/mL in study subjects. The adiponectin levels were inversely related to the angiographic severity of coronary artery stenosis increases (P value > 0.02). The study concluded that higher adiponectin levels are independently associated with lower risk of ACS, and patients with severe angiographic coronary artery disease have lower levels of adiponectin.

Three vs Twelve Months of Dual Antiplatelet Therapy After Zotarolimus-Eluting Stents

The current recommendation is for at least 12 months of dual antiplatelet therapy after implantation of a drug-eluting stent. However, the optimal duration of dual antiplatelet therapy with specific types of drug-eluting stents remains unknown. To assess the clinical noninferiority of 3 months (short-term) vs 12 months (long-term) of dual antiplatelet therapy in patients undergoing percutaneous coronary intervention (PCI) with zotarolimus-eluting stents. The OPTIMIZE trial was an open-label, active-controlled, 1:1 randomized noninferiority study including 3119 patients in 33 sites in Brazil between April 2010 and March 2012. Clinical follow-up was performed at 1, 3, 6, and 12 months. Eligible patients were those with stable coronary artery disease or history of low-risk acute coronary syndrome (ACS) undergoing PCI with zotarolimus-eluting stents. After PCI with zotarolimus-eluting stents, patients were prescribed aspirin (100-200 mg daily) and clopidogrel (75 mg daily) for 3 months (n = 1563) or 12 months (n = 1556), unless contraindicated because of occurrence of an end point. The primary end point was net adverse clinical and cerebral events (NACCE; a composite of all-cause death, myocardial infarction [MI], stroke, or major bleeding); the expected event rate at 1 year was 9%, with a noninferiority margin of 2.7%. Secondary end points were major adverse cardiac events (MACE; a composite of all-cause death, MI, emergent coronary artery bypass graft surgery, or target lesion revascularization) and Academic Research Consortium definite or probable stent thrombosis. NACCE occurred in 93 patients receiving short-term and 90 patients receiving long-term therapy (6.0% vs 5.8%, respectively; risk difference, 0.17 [95% CI, -1.52 to 1.86]; P = .002 for noninferiority). Kaplan-Meier estimates demonstrated MACE rates at 1 year of 8.3% (128) in the short-term group and 7.4% (114) in the long-term group (HR, 1.12 [95% CI, 0.87-1.45]). Between 91 and 360 days, no statistically significant association was observed for NACCE (39 [2.6%] vs 38 [2.6%] for the short- and long-term groups, respectively; HR, 1.03 [95% CI, 0.66-1.60]), MACE (78 [5.3%] vs 64 [4.3%]; HR, 1.22 [95% CI, 0.88-1.70]), or stent thrombosis (4 [0.3%] vs 1 [0.1%]; HR, 3.97 [95% CI, 0.44-35.49]). In patients with stable coronary artery disease or low-risk ACS treated with zotarolimus-eluting stents, 3 months of dual antiplatelet therapy was noninferior to 12 months for NACCE, without significantly increasing the risk of stent thrombosis. clinicaltrials.gov Identifier: NCT01113372.