Effect of Alirocumab on Incidence of Atrial Fibrillation After Acute Coronary Syndromes: Insights from the ODYSSEY OUTCOMES Trial

BACKGROUND

Using data from the ODYSSEY OUTCOMES trial (NCT01663402), we sought to identify factors associated with the development of incident atrial fibrillation in patients with recent acute coronary syndrome without prior atrial fibrillation and to determine whether alirocumab treatment influenced risk of incident atrial fibrillation.

METHODS

ODYSSEY OUTCOMES compared alirocumab treatment with placebo in 18,924 patients with recent acute coronary syndrome and dyslipidemia despite high-intensity or maximum-tolerated statin therapy. The primary outcome of major adverse cardiovascular events (MACE) comprised death from coronary heart disease, non-fatal myocardial infarction, fatal or non-fatal ischemic stroke, or unstable angina requiring hospitalization. Patients were classified as having previous atrial fibrillation (present prior to or at randomization) or no previous atrial fibrillation. A multivariable model was used to determine factors associated with incident atrial fibrillation.

RESULTS

Among 18,262 participants without prior atrial fibrillation at baseline, 499 (2.7%) had incident atrial fibrillation during follow-up. Older age, history of heart failure or myocardial infarction, and higher body mass index were significantly associated with incident atrial fibrillation. Treatment with alirocumab or placebo did not influence the cumulative incidence of atrial fibrillation (hazard ratio 0.91; 95% confidence interval, 0.77-1.09). Patients with vs without a history of atrial fibrillation had a higher incidence of MACE (8.8 vs 3.7 events per 100 patient-years), without significant interaction between atrial fibrillation and randomized treatment on risk of MACE (P_interaction = .78).

CONCLUSIONS

While alirocumab did not modify risk of incident atrial fibrillation after acute coronary syndrome, it did reduce the risk of MACE, regardless of prior atrial fibrillation history. History of atrial fibrillation is an independent predictor of recurrent cardiovascular events after acute coronary syndrome.

Efficacy and Safety of Dapagliflozin in Type 2 Diabetes According to Baseline Blood Pressure: Observations From DECLARE-TIMI 58 Trial

Background: Dapagliflozin improved heart failure and kidney outcomes in patients with type 2 diabetes mellitus (T2DM) with or at high risk for cardiovascular disease in the DECLARE-TIMI 58 trial. Here, the aim was to analyze efficacy and safety of dapagliflozin stratified according to baseline systolic blood pressure (SBP). Methods: The DECLARE-TIMI 58 trial randomized patients with T2DM and either prior atherosclerotic cardiovascular disease (ASCVD) or ASCVD risk factors to dapagliflozin or placebo. Patients were categorized by baseline SBP levels: < 120, 120-129, 130-139, 140-159 and ≥ 160 mmHg (respectively, normal, elevated, stage 1, stage 2 and severe hypertension). Efficacy outcomes of interest were hospitalization for heart failure (HHF) and a renal-specific composite outcome (sustained decrease in estimated glomerular filtration rate by 40%, progression to end-stage renal disease or renal death). Safety outcomes included symptoms of volume depletion, lower extremity amputations and acute kidney injury. Results: The trial comprised 17,160 patients; mean age of 64.0 ± 6.8 years ; 37.4% women; median duration of T2DM 11 years; 40.6% with prevalent CVD. Overall, dapagliflozin reduced SBP by 2.4 mmHg (95% CI 1.9-2.9; p < 0.0001) compared with placebo at 48 months. The beneficial effects of dapagliflozin on HHF and renal outcomes were consistent across all baseline SBP categories, with no evidence of modification of treatment effect (p-interactions = 0.28 and 0.52, respectively). Among normotensive patients, the HR´s were 0.66 (95% CI 0.42-1.05) and 0.39 (95% CI 0.19-0.78), respectively for HHF and the renal specific outcome. Events of volume depletion, amputation and acute kidney injury did not differ with dapagliflozin overall or within any baseline SBP group. Conclusions: In patients with T2DM with or at high ASCVD risk, dapagliflozin reduced risk for HHF and renal outcomes regardless of baseline systolic blood pressure, with no difference in adverse events of interest at any level of baseline SBP. These results indicate that dapagliflozin provides important cardiorenal benefit in patients with T2DM at high ASCVD risk, independent of baseline blood pressure.

In patients with stable coronary heart disease, low-density lipoprotein-cholesterol levels < 70 mg/dL and glycosylated hemoglobin A1c < 7% are associated with lower major cardiovascular events

BACKGROUND

In patients with stable coronary heart disease, it is not known whether achievement of standard of care (SOC) targets in addition to evidence-based medicine (EBM) is associated with lower major adverse cardiovascular events (MACE): cardiovascular death, myocardial infarction, and stroke.

METHODS

EBM use was recommended in the STabilisation of Atherosclerotic plaque By Initiation of darapLadIb TherapY trial. SOC targets were blood pressure (BP) <140/90 mm Hg and low-density lipoprotein-cholesterol (LDL-C) <100 mg/dL and <70 mg/dL. In patients with diabetes, glycosylated hemoglobin A1c (HbA1c) < 7% and BP of <130/80 mm Hg were recommended. Feedback to investigators about rates of EBM and SOC was provided regularly.

RESULTS

In 13,623 patients, 1-year landmark analysis assessed the association between EBM, SOC targets, and MACE during follow-up of 2.7 years (median) after adjustment in a Cox proportional hazards model. At 1 year, aspirin was prescribed in 92.5% of patients, statins in 97.2%, β-blockers in 79.0%, and angiotensin-converting enzyme inhibitors/angiotensin-II receptor blockers in 76.9%. MACE was lower with LDL-C < 100 mg/dL (70-99 mg/dL) compared with LDL-C ≥ 100 mg/dL (hazard ratio [HR] 0.694, 95% CI 0.594-0.811) and lower with LDL-C < 70 mg/dL compared with LDL-C < 100 mg/dL (70-99 mg/dL) (HR 0.834, 95% CI 0.708-0.983). MACE was lower with HbA1c < 7% compared with HbA1c ≥ 7% (HR 0.705, 95% CI 0.573-0.866). There was no effect of BP targets on MACE.

CONCLUSIONS

MACE was lower with LDL-C < 100 mg/dL (70-99 mg/dL) and even lower with LDL-C < 70 mg/dL. MACE in patients with diabetes was lower with HbA1c < 7%. Achievement of targets is associated with improved patient outcomes.

Effect of Alirocumab on Mortality After Acute Coronary Syndromes

Supplemental Digital Content is available in the text.

Background:

Previous trials of PCSK9 (proprotein convertase subtilisin-kexin type 9) inhibitors demonstrated reductions in major adverse cardiovascular events, but not death. We assessed the effects of alirocumab on death after index acute coronary syndrome.

Methods:

ODYSSEY OUTCOMES (Evaluation of Cardiovascular Outcomes After an Acute Coronary Syndrome During Treatment With Alirocumab) was a double-blind, randomized comparison of alirocumab or placebo in 18 924 patients who had an ACS 1 to 12 months previously and elevated atherogenic lipoproteins despite intensive statin therapy. Alirocumab dose was blindly titrated to target achieved low-density lipoprotein cholesterol (LDL-C) between 25 and 50 mg/dL. We examined the effects of treatment on all-cause death and its components, cardiovascular and noncardiovascular death, with log-rank testing. Joint semiparametric models tested associations between nonfatal cardiovascular events and cardiovascular or noncardiovascular death.

Results:

Median follow-up was 2.8 years. Death occurred in 334 (3.5%) and 392 (4.1%) patients, respectively, in the alirocumab and placebo groups (hazard ratio [HR], 0.85; 95% CI, 0.73 to 0.98; P=0.03, nominal P value). This resulted from nonsignificantly fewer cardiovascular (240 [2.5%] vs 271 [2.9%]; HR, 0.88; 95% CI, 0.74 to 1.05; P=0.15) and noncardiovascular (94 [1.0%] vs 121 [1.3%]; HR, 0.77; 95% CI, 0.59 to 1.01; P=0.06) deaths with alirocumab. In a prespecified analysis of 8242 patients eligible for ≥3 years follow-up, alirocumab reduced death (HR, 0.78; 95% CI, 0.65 to 0.94; P=0.01). Patients with nonfatal cardiovascular events were at increased risk for cardiovascular and noncardiovascular deaths (P<0.0001 for the associations). Alirocumab reduced total nonfatal cardiovascular events (P<0.001) and thereby may have attenuated the number of cardiovascular and noncardiovascular deaths. A post hoc analysis found that, compared to patients with lower LDL-C, patients with baseline LDL-C ≥100 mg/dL (2.59 mmol/L) had a greater absolute risk of death and a larger mortality benefit from alirocumab (HR, 0.71; 95% CI, 0.56 to 0.90; P_interaction=0.007). In the alirocumab group, all-cause death declined with achieved LDL-C at 4 months of treatment, to a level of approximately 30 mg/dL (adjusted P=0.017 for linear trend).

Conclusions:

Alirocumab added to intensive statin therapy has the potential to reduce death after acute coronary syndrome, particularly if treatment is maintained for ≥3 years, if baseline LDL-C is ≥100 mg/dL, or if achieved LDL-C is low.

Clinical Trial Registration:

URL: https://www.clinicaltrials.gov. Unique identifier: NCT01663402.

Prevention of Stroke with the Addition of Ezetimibe to Statin Therapy in Patients With Acute Coronary Syndrome in IMPROVE-IT (Improved Reduction of Outcomes: Vytorin Efficacy International Trial)

BACKGROUND

Patients who experience an acute coronary syndrome are at heightened risk of recurrent ischemic events, including stroke. Ezetimibe improved cardiovascular outcomes when added to statin therapy in patients stabilized after acute coronary syndrome. We investigated the efficacy of the addition of ezetimibe to simvastatin for the prevention of stroke and other adverse cardiovascular events in IMPROVE-IT (Improved Reduction of Outcomes: Vytorin Efficacy International Trial), with a focus on patients with a stroke before randomization.

METHODS

Patients who experienced acute coronary syndrome were randomized to a placebo/simvastatin or ezetimibe/simvastatin regimen and followed for a median of 6 years. Treatment efficacy was assessed for the entire population and by subgroups for the first and total (first and subsequent) events for the end points of stroke of any etiology, stroke subtypes, and the primary trial end point at 7 years.

RESULTS

Of 18 144 patients, 641 (3.5%) experienced at least 1 stroke; most were ischemic (527, 82%). Independent predictors of stroke included prior stroke, older age, atrial fibrillation, congestive heart failure, diabetes mellitus, myocardial infarction, and renal dysfunction. There was a nonsignificant reduction in the first event of stroke of any etiology (4.2% versus 4.8%; hazard ratio [HR], 0.86; 95% confidence interval [CI], 0.73-1.00; P=0.052) with ezetimibe/simvastatin versus placebo/simvastatin, driven by a significant 21% reduction in ischemic stroke (3.4% versus 4.1%; HR, 0.79; 95% CI, 0.67-0.94; P=0.008) and a nonsignificant increase in hemorrhagic stroke (0.8% versus 0.6%; HR, 1.38; 95% CI, 0.93-2.04; P=0.11). Evaluating total events, including the first and all recurrent strokes, ezetimibe/simvastatin reduced stroke of any etiology (HR, 0.83; 95% CI, 0.70-0.98; P=0.029) and ischemic stroke (HR, 0.76; 95% CI, 0.63-0.91; P=0.003). Patients who had experienced a stroke prior to randomization were at a higher risk of recurrence and demonstrated an absolute risk reduction of 8.6% for stroke of any etiology (10.2% versus 18.8%; number needed to treat=12; HR, 0.60; 95% CI, 0.38-0.95; P=0.030) and 7.6% for ischemic stroke (8.7% versus 16.3%; number needed to treat=13; HR, 0.52; 95% CI, 0.31-0.86; P=0.011) with ezetimibe added to simvastatin therapy.

CONCLUSIONS

The addition of ezetimibe to simvastatin in patients stabilized after acute coronary syndrome reduces the frequency of ischemic stroke, with a particularly large effect seen in patients with a prior stroke.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT00202878.

Dual antiplatelet therapy in patients with diabetes and acute coronary syndromes managed without revascularization

OBJECTIVE

Patients with diabetes mellitus (DM) presenting with acute coronary syndrome (ACS) and undergoing percutaneous coronary intervention (PCI) derived enhanced benefit with dual antiplatelet therapy (DAPT) with prasugrel vs. clopidogrel. The risk profile and treatment response to DAPT for medically managed ACS patients with DM remains uncertain.

METHODS

The TRILOGY ACS trial compared aspirin + prasugrel vs. aspirin + clopidogrel for up to 30months in non-ST-segment elevation (NSTE) ACS patients managed medically without revascularization. We compared treatment-related outcomes among 3539 patients with DM vs. 5767 patients without DM. The primary endpoint was a composite of cardiovascular death, myocardial infarction, or stroke.

RESULTS

Patients with vs. without DM were younger, more commonly female, heavier, and more often had revascularization prior to the index ACS event. The frequency of the primary endpoint through 30months was higher among patients with vs. without DM (24.8% vs. 16.3%), with a higher risk for those patients with DM treated with insulin vs. those treated without insulin (35.3% vs. 19.9%). There was no significant difference in the frequency of the primary endpoint by treatment with prasugrel vs. clopiodgrel in those with or without DM (P_int=0.82) and with or without insulin treatment among those with DM (P_int=0.304).

CONCLUSIONS

Among NSTE ACS patients managed medically without revascularization, patients with DM had a higher risk of ischemic events that was amplified among those treated with insulin. There was no differential treatment effect with a more potent DAPT regimen of aspirin + prasugrel vs. aspirin + clopidogrel.

Predictors of Nonuse of a High-Potency Statin After an Acute Coronary Syndrome: Insights From the Stabilization of Plaques Using Darapladib-Thrombolysis in Myocardial Infarction 52 (SOLID-TIMI 52) Trial

Background

High‐potency statins reduce cardiovascular events after acute coronary syndromes but remain underused in clinical practice. We examined predictors of nonuse of high‐potency statins after acute coronary syndromes.

Methods and Results

The Stabilization of pLaques usIng Darapladib‐Thrombolysis in Myocardial Infarction (SOLID‐TIMI 52) trial enrolled patients after an acute coronary syndrome in 36 countries between 2009 and 2011. Statin use was strongly encouraged throughout the trial, and statin potency was at the discretion of the treating physician. A high‐potency statin was defined as ≥40 mg atorvastatin, ≥20 mg rosuvastatin, or 80 mg simvastatin daily. Predictors of nonuse of high‐potency statins were examined using logistic regression. Of the patients included (n=12 446), 11 850 (95.2%) were treated with a statin at baseline after acute coronary syndrome (median 14 days), but only 5212 (41.9%) were on a high‐potency statin. Selected patient factors associated with nonuse of high‐potency statins included age ≥75 years (odds ratio 1.39, 95% CI 1.24–1.56), female sex (odds ratio 1.11, 95% CI 1.02–1.22), renal dysfunction (odds ratio 1.17, 95% CI 1.03–1.32), and heart failure during hospital admission (odds ratio 1.43, 95% CI 1.27–1.62). At 3 months after baseline, only 49% of patients had low‐density lipoprotein cholesterol <70 mg/dL. Among the 5490 patients (59%) who were not on a high‐potency statin at 3 months, lower low‐density lipoprotein cholesterol was a predictor of nonuse of a high‐potency statin after a median of 2.3 years (odds ratio 1.15 for 10 mg/dL decrease, 95% CI 1.11–1.19).

Conclusion

Despite the widespread use of statins after acute coronary syndromes, most patients are not treated with high‐potency statins early and late after the event, including patients at the highest risk of recurrent cardiovascular events.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01000727.

Prevention of Stroke with Ticagrelor in Patients with Prior Myocardial Infarction

Background:

In the PEGASUS-TIMI 54 trial (Prevention of Cardiovascular Events in Patients With Prior Heart Attack Using Ticagrelor Compared to Placebo on a Background of Aspirin-Thrombolysis in Myocardial Infarction 54), ticagrelor reduced the risk of major adverse cardiovascular events when added to low-dose aspirin in stable patients with prior myocardial infarction, resulting in the approval of ticagrelor 60 mg twice daily for long-term secondary prevention. We investigated the incidence of stroke, outcomes after stroke, and the efficacy of ticagrelor focusing on the approved 60 mg twice daily dose for reducing stroke in this population.

Methods:

Patients were followed for a median of 33 months. Stroke events were adjudicated by a central committee. Data from similar trials were combined using meta-analysis.

Results:

Of 14 112 patients randomly assigned to placebo or ticagrelor 60 mg, 213 experienced a stroke; 85% of these strokes were ischemic. A total of 18% of strokes were fatal and another 15% led to either moderate or severe disability at 30 days. Ticagrelor significantly reduced the risk of stroke (hazard ratio, 0.75; 95% confidence interval, 0.57–0.98; P =0.034), driven by a reduction in ischemic stroke (hazard ratio, 0.76; 95% confidence interval, 0.56–1.02). Hemorrhagic stroke occurred in 9 patients on placebo and 8 patients on ticagrelor. A meta-analysis across 4 placebo-controlled trials of more intensive antiplatelet therapy in 44 816 patients with coronary disease confirmed a marked reduction in ischemic stroke (hazard ratio, 0.66; 95% confidence interval, 0.54–0.81; P =0.0001).

Conclusions:

High-risk patients with prior myocardial infarction are at risk for stroke, approximately one-third of which are fatal or lead to moderate-to-severe disability. The addition of ticagrelor 60 mg twice daily significantly reduced this risk without an excess of hemorrhagic stroke but with more major bleeding. In high-risk patients with coronary disease, more intensive antiplatelet therapy should be considered not only to reduce the risk of coronary events, but also of stroke.

Clinical Trial Registration:

URL: http://www.clinicaltrials.gov . Unique Identifier: NCT01225562.

Effect of prior clopidogrel use on outcomes in medically managed acute coronary syndrome patients

OBJECTIVE

We investigated whether prior clopidogrel influenced long-term ischaemic and bleeding risks and modified the randomised treatment effect of clopidogrel versus prasugrel among medically managed patients with acute coronary syndromes (ACS) treated with dual antiplatelet therapy.

METHODS

Medically managed patients with ACS in the Targeted Platelet Inhibition to Clarify the Optimal Strategy to Medically Manage Acute Coronary Syndromes (TRILOGY ACS) trial were randomised to clopidogrel versus prasugrel (plus aspirin), stratified by prior clopidogrel use. From the analysis population (n=8927), we compared two groups: 'clopidogrel in-hospital (n=6513)' (clopidogrel started ≤72 h of presentation for index ACS event) and 'prior-clopidogrel (n=2414)' (on clopidogrel ≥5 days before index hospitalisation). Treatment-related differences in ischaemic (all-cause death, cardiovascular (CV) death, myocardial infarction (MI), stroke and the composite of CV death/MI/stroke) and bleeding outcomes (severe/life-threatening or moderate bleeding events based on Global Use of Strategies to Open Occluded Coronary Arteries (GUSTO) criteria) through 30 months were analysed between patients in the two groups.

RESULTS

Compared with 'clopidogrel in-hospital,' 'prior clopidogrel' patients were younger (median 64 years vs 66 years, p<0.001), more likely to have prior CV events/revascularisation, and had a higher frequency of CV death, MI or stroke through 30 months (20.8% vs 18.2%, p=0.002), with no difference in bleeding events (2.3% vs 3.4%, p=0.50). Randomised treatment effect (prasugrel vs clopidogrel) was similar for ischaemic and bleeding outcomes in both groups (all pinteraction>0.05).

CONCLUSIONS

Patients receiving clopidogrel before admission for ACS and subsequently treated only medically are at higher risk for CV events versus those not previously receiving clopidogrel. More potent antiplatelet inhibition with prasugrel versus clopidogrel did not significantly reduce this risk.

TRIAL REGISTRATION NUMBER

NCT00699998.

Spontaneous coronary artery dissection associated with fibromuscular dysplasia

This case presentation concerns a woman known to have fibromuscular dysplasia (FMD) who presented with an acute coronary syndrome (ACS). The coronary angiogram was considered to be normal. However, as spontaneous coronary artery dissection (SCAD) has a close association with FMD, subsequent meticulous review of the angiogram revealed a dissection within the circumflex coronary artery. SCAD causes 10% of ACS seen in women under 55 years of age. Both FMD and SCAD are underdiagnosed and SCAD may be overlooked or misdiagnosed on coronary angiography. The recommended management of SCAD differs from that of the usual presentations of ACS. For this reason, one should be alert to the possibility of SCAD when confronted by ACS in a younger woman, especially when she is known to have FMD.

Efficacy and safety of vorapaxar as approved for clinical use in the United States

BACKGROUND

Vorapaxar is a protease-activated receptor-1 antagonist approved by the U.S. Food and Drug Administration (FDA) for the reduction of thrombotic cardiovascular (CV) events in patients with a history of myocardial infarction (MI) and peripheral artery disease (PAD), without a previous stroke or transient ischemic attack (TIA).

METHODS AND RESULTS

We examined the efficacy and safety of vorapaxar in the intended use population, considering 20,170 patients randomized in the multinational, double-blinded, placebo-controlled TRA 2°P-TIMI 50 trial. Of these, 16,897 qualified with a history of MI in the prior 2 weeks to 1 year and 3273 with PAD. At baseline 97% of the patients were treated with aspirin, 71% with a thienopyridine, and 93% a statin. At 3 years, the endpoint of CV death, MI, or stroke was significantly reduced with vorapaxar compared with placebo (7.9% versus 9.5%, HR, 0.80; 95% CI 0.73 to 0.89; P<0.001). Vorapaxar also significantly reduced the composite of CV death, MI, stroke, and urgent coronary revascularization (10.1% versus 11.8%, HR, 0.83; 95% CI 0.76 to 0.90; P<0.001), as well as the rate of CV death or MI (P<0.001). The safety endpoint of GUSTO moderate or severe bleeding, was increased in the vorapaxar group (3.7 versus 2.4, HR, 1.55; 95% CI 1.30 to 1.86, P<0.001). Intracranial bleeding (ICH) was 0.6% versus 0.4%, P=0.10 with vorapaxar versus placebo, with fatal bleeding 0.2% versus 0.2%; P=0.70.

CONCLUSIONS

In patients with prior MI or PAD who have not had a previous stroke or TIA, vorapaxar added to standard therapy is effective for long-term secondary prevention of thrombotic CV events, while increasing moderate or severe bleeding.

CLINICAL TRIAL REGISTRATION

URL: clinicaltrials.gov Unique Identifier: NCT00526474.

Vorapaxar in patients with diabetes mellitus and previous myocardial infarction: findings from the thrombin receptor antagonist in secondary prevention of atherothrombotic ischemic events-TIMI 50 trial

Supplemental Digital Content is available in the text.

Background—

Vorapaxar reduces cardiovascular death, myocardial infarction (MI), or stroke in patients with previous MI while increasing bleeding. Patients with diabetes mellitus (DM) are at high risk of recurrent thrombotic events despite standard therapy and may derive particular benefit from antithrombotic therapies. The Thrombin Receptor Antagonist in Secondary Prevention of Atherothrombotic Ischemic Events-TIMI 50 trial was a randomized, double-blind, placebo-controlled trial of vorapaxar in patients with stable atherosclerosis.

Methods and Results—

We examined the efficacy of vorapaxar in patients with and without DM who qualified for the trial with a previous MI. Because vorapaxar is contraindicated in patients with a history of stroke or transient ischemic attack, the analysis (n=16 896) excluded such patients. The primary end point of cardiovascular death, MI, or stroke occurred more frequently in patients with DM than in patients without DM (rates in placebo group: 14.3% versus 7.6%; adjusted hazard ratio, 1.47; P<0.001). In patients with DM (n=3623), vorapaxar significantly reduced the primary end point (11.4% versus 14.3%; hazard ratio, 0.73 [95% confidence interval, 0.60–0.89]; P=0.002) with a number needed to treat to avoid 1 major cardiovascular event of 29. The incidence of moderate/severe bleeding was increased with vorapaxar in patients with DM (4.4% versus 2.6%; hazard ratio, 1.60 [95% confidence interval, 1.07–2.40]). However, net clinical outcome integrating these 2 end points (efficacy and safety) was improved with vorapaxar (hazard ratio, 0.79 [95% confidence interval, 0.67–0.93]).

Conclusions—

In patients with previous MI and DM, the addition of vorapaxar to standard therapy significantly reduced the risk of major vascular events with greater potential for absolute benefit in this group at high risk of recurrent ischemic events.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00526474.

Duration of eptifibatide infusion after percutaneous coronary intervention and outcomes among high-risk patients with non-ST-segment elevation acute coronary syndrome: insights from EARLY ACS

BACKGROUND AND OBJECTIVES

Eptifibatide is indicated during percutaneous coronary intervention (PCI) with continuation for 18-24 hours post procedure but is associated with bleeding. We examined the efficacy and safety of shorter post-PCI eptifibatide infusions in high-risk non-ST-segment elevation acute coronary syndrome (NSTE ACS) patients.

METHODS

EARLY ACS patients treated with PCI and eptifibatide were grouped by post-procedure infusion duration: <10, 10-13, 13-17, and 17-25 (per protocol) hours. Adjusted estimated event rates for 96-hour death/myocardial infarction (MI)/recurrent ischaemia requiring urgent revascularization (RIUR), 30-day death/MI, post-PCI packed red blood cell (PRBC) transfusion, and GUSTO (Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries) moderate/severe bleeding were obtained using inverse-propensity weighting to account for informative censoring of infusions.

RESULTS

Among 3271 eptifibatide-treated PCI patients, there were 66 96-hour death/MI/RIUR events, 94 30-day death/MI events, 127 PRBC transfusions, and 115 GUSTO moderate/severe bleeds. Compared with per protocol, patients receiving post-PCI infusions <10 hours had similar adjusted estimated rates of 96-hour death/MI/RIUR (absolute difference 0.021 higher; 0.040 vs. 0.019, 95% CI -0.023 to 0.064; p=0.35) and 30-day death/MI (0.020 higher; 0.046 vs. 0.026, 95% CI -0.021 to 0.062; p=0.34). There were also no differences in ischaemic outcomes between infusions of 10-17 hours and per-protocol infusions. Adjusted estimated rates of PRBC transfusion were higher for the <10-hour infusion group compared with per protocol (0.048 higher; 0.079 vs. 0.031, 95% CI 0.005 to 0.091, p=0.03) but were similar for other groups. Adjusted GUSTO moderate/severe bleeding rates were similar to per-protocol rates for all groups.

CONCLUSIONS

In high-risk NSTE ACS patients, post-PCI eptifibatide infusions <18 hours were not associated with worse ischaemic outcomes. Shorter eptifibatide infusions in this population may be feasible.

Darapladib for preventing ischemic events in stable coronary heart disease

BACKGROUND

Elevated lipoprotein-associated phospholipase A2 activity promotes the development of vulnerable atherosclerotic plaques, and elevated plasma levels of this enzyme are associated with an increased risk of coronary events. Darapladib is a selective oral inhibitor of lipoprotein-associated phospholipase A2.

METHODS

In a double-blind trial, we randomly assigned 15,828 patients with stable coronary heart disease to receive either once-daily darapladib (at a dose of 160 mg) or placebo. The primary end point was a composite of cardiovascular death, myocardial infarction, or stroke. Secondary end points included the components of the primary end point as well as major coronary events (death from coronary heart disease, myocardial infarction, or urgent coronary revascularization for myocardial ischemia) and total coronary events (death from coronary heart disease, myocardial infarction, hospitalization for unstable angina, or any coronary revascularization).

RESULTS

During a median follow-up period of 3.7 years, the primary end point occurred in 769 of 7924 patients (9.7%) in the darapladib group and 819 of 7904 patients (10.4%) in the placebo group (hazard ratio in the darapladib group, 0.94; 95% confidence interval [CI], 0.85 to 1.03; P=0.20). There were also no significant between-group differences in the rates of the individual components of the primary end point or in all-cause mortality. Darapladib, as compared with placebo, reduced the rate of major coronary events (9.3% vs. 10.3%; hazard ratio, 0.90; 95% CI, 0.82 to 1.00; P=0.045) and total coronary events (14.6% vs. 16.1%; hazard ratio, 0.91; 95% CI, 0.84 to 0.98; P=0.02).

CONCLUSIONS

In patients with stable coronary heart disease, darapladib did not significantly reduce the risk of the primary composite end point of cardiovascular death, myocardial infarction, or stroke. (Funded by GlaxoSmithKline; STABILITY ClinicalTrials.gov number, NCT00799903.).

Elderly Patients With Acute Coronary Syndromes Managed Without Revascularization

Background—

Dual antiplatelet therapy in older versus younger patients with acute coronary syndromes is understudied. Low-dose prasugrel (5 mg/d) is recommended for younger, lower-body-weight patients and elderly patients with acute coronary syndromes to mitigate the bleeding risk of standard-dose prasugrel (10 mg/d).

Methods and Results—

A total of 9326 medically managed patients with acute coronary syndromes from the Targeted Platelet Inhibition to Clarify the Optimal Strategy to Medically Manage Acute Coronary Syndromes (TRILOGY ACS) trial (<75 years of age, n=7243; ≥75 years of age, n=2083) were randomized to prasugrel (10 mg/d; 5 mg/d for those ≥75 or <75 years of age and <60 kg in weight) or clopidogrel (75 mg/d) plus aspirin for ≤30 months. A total of 515 participants ≥75 years of age (25% of total elderly population) had serial platelet reactivity unit measurements in a platelet-function substudy. Cumulative risks of the primary end point (cardiovascular death/myocardial infarction/stroke) and Thrombolysis in Myocardial Infarction (TIMI) major bleeding increased progressively with age and were ≥2-fold higher in older participants. Among those ≥75 years of age, TIMI major bleeding (4.1% versus 3.4%; hazard ratio, 1.09; 95% confidence interval, 0.57–2.08) and the primary end point rates were similar with reduced-dose prasugrel and clopidogrel. Despite a correlation between lower 30-day on-treatment platelet reactivity unit values and lower weight only in the prasugrel group, there was a nonsignificant treatment-by-weight interaction for platelet reactivity unit values among participants ≥75 years of age in the platelet-function substudy ( P =0.06). No differences in weight were seen in all participants ≥75 years of age with versus without TIMI major/minor bleeding in both treatment groups.

Conclusions—

Older age is associated with substantially increased long-term cardiovascular risk and bleeding among patients with medically managed acute coronary syndromes, with no differences in ischemic or bleeding outcomes with reduced-dose prasugrel compared with clopidogrel in elderly patients. No significant interactions among weight, pharmacodynamic response, and bleeding risk were observed between reduced-dose prasugrel and clopidogrel in elderly patients.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov/ct2/home . Unique identifier: NCT0069999.

Prevalence and clinical outcomes of undiagnosed diabetes mellitus and prediabetes among patients with high-risk non-ST-segment elevation acute coronary syndrome

BACKGROUND

We examined the prevalence of undiagnosed diabetes or prediabetes and associations with ischemic outcomes among non-ST-segment elevation acute coronary syndrome (ACS) patients.

METHODS

We categorized 8795 EARLY ACS trial patients into one of the following groups: "known diabetes" (n = 2860 [32.5%]; reported on the case report form), "undiagnosed diabetes" (n = 1069 [12.2%]; no diabetes history and fasting glucose ≥126 mg/dL or hemoglobin A1c ≥6.5%), "prediabetes" (n = 947 [10.8%]; fasting glucose ≥110 to <126 mg/dL, or "normal" (n = 3919 [44.5%]). Adjusted associations of known diabetes, undiagnosed diabetes, and prediabetes (versus normal) with 30-day and 1-year outcomes were determined.

RESULTS

Undiagnosed diabetes was associated with greater 30-day death or myocardial infarction (MI) (ORadj 1.28, 95% CI 1.05-1.57), driven primarily by greater 30-day mortality (ORadj 1.65, 95% CI 1.09-2.48). Known diabetic patients had 30-day death or MI outcomes similar to those of normal patients, but 30-day mortality was higher (ORadj 1.40, 95% CI 1.01-1.93). Prediabetic patients had 30-day death or MI outcomes similar to those of normal patients. One-year mortality was greater among known diabetic patients (HRadj 1.38, 95% CI 1.13-1.67) but not among those with undiagnosed diabetes or prediabetes.

CONCLUSIONS

Undiagnosed diabetes and prediabetes were common among high-risk non-ST-segment elevation ACS patients. Routine screening for undiagnosed diabetes may be useful since these patients seem to have worse short-term outcomes and deserve consideration of alternative management strategies.

Prasugrel versus clopidogrel for acute coronary syndromes without revascularization

BACKGROUND

The effect of intensified platelet inhibition for patients with unstable angina or myocardial infarction without ST-segment elevation who do not undergo revascularization has not been delineated.

METHODS

In this double-blind, randomized trial, in a primary analysis involving 7243 patients under the age of 75 years receiving aspirin, we evaluated up to 30 months of treatment with prasugrel (10 mg daily) versus clopidogrel (75 mg daily). In a secondary analysis involving 2083 patients 75 years of age or older, we evaluated 5 mg of prasugrel versus 75 mg of clopidogrel.

RESULTS

At a median follow-up of 17 months, the primary end point of death from cardiovascular causes, myocardial infarction, or stroke among patients under the age of 75 years occurred in 13.9% of the prasugrel group and 16.0% of the clopidogrel group (hazard ratio in the prasugrel group, 0.91; 95% confidence interval [CI], 0.79 to 1.05; P=0.21). Similar results were observed in the overall population. The prespecified analysis of multiple recurrent ischemic events (all components of the primary end point) suggested a lower risk for prasugrel among patients under the age of 75 years (hazard ratio, 0.85; 95% CI, 0.72 to 1.00; P=0.04). Rates of severe and intracranial bleeding were similar in the two groups in all age groups. There was no significant between-group difference in the frequency of nonhemorrhagic serious adverse events, except for a higher frequency of heart failure in the clopidogrel group.

CONCLUSIONS

Among patients with unstable angina or myocardial infarction without ST-segment elevation, prasugrel did not significantly reduce the frequency of the primary end point, as compared with clopidogrel, and similar risks of bleeding were observed. (Funded by Eli Lilly and Daiichi Sankyo; TRILOGY ACS ClinicalTrials.gov number, NCT00699998.).

Vorapaxar in the secondary prevention of atherothrombotic events

BACKGROUND

Thrombin potently activates platelets through the protease-activated receptor PAR-1. Vorapaxar is a novel antiplatelet agent that selectively inhibits the cellular actions of thrombin through antagonism of PAR-1.

METHODS

We randomly assigned 26,449 patients who had a history of myocardial infarction, ischemic stroke, or peripheral arterial disease to receive vorapaxar (2.5 mg daily) or matching placebo and followed them for a median of 30 months. The primary efficacy end point was the composite of death from cardiovascular causes, myocardial infarction, or stroke. After 2 years, the data and safety monitoring board recommended discontinuation of the study treatment in patients with a history of stroke owing to the risk of intracranial hemorrhage.

RESULTS

At 3 years, the primary end point had occurred in 1028 patients (9.3%) in the vorapaxar group and in 1176 patients (10.5%) in the placebo group (hazard ratio for the vorapaxar group, 0.87; 95% confidence interval [CI], 0.80 to 0.94; P<0.001). Cardiovascular death, myocardial infarction, stroke, or recurrent ischemia leading to revascularization occurred in 1259 patients (11.2%) in the vorapaxar group and 1417 patients (12.4%) in the placebo group (hazard ratio, 0.88; 95% CI, 0.82 to 0.95; P=0.001). Moderate or severe bleeding occurred in 4.2% of patients who received vorapaxar and 2.5% of those who received placebo (hazard ratio, 1.66; 95% CI, 1.43 to 1.93; P<0.001). There was an increase in the rate of intracranial hemorrhage in the vorapaxar group (1.0%, vs. 0.5% in the placebo group; P<0.001).

CONCLUSIONS

Inhibition of PAR-1 with vorapaxar reduced the risk of cardiovascular death or ischemic events in patients with stable atherosclerosis who were receiving standard therapy. However, it increased the risk of moderate or severe bleeding, including intracranial hemorrhage. (Funded by Merck; TRA 2P-TIMI 50 ClinicalTrials.gov number, NCT00526474.).

Predictors of bleeding and time dependence of association of bleeding with mortality: insights from the Trial to Assess Improvement in Therapeutic Outcomes by Optimizing Platelet Inhibition With Prasugrel--Thrombolysis in Myocardial Infarction 38 (TRITON-TIMI 38)

BACKGROUND

The balance between benefit (ischemia protection) and risk (bleeding) is a key consideration in choosing the intensity of antiplatelet therapy for patients with acute coronary syndromes. The goals of this analysis were to identify baseline characteristics that independently predict bleeding and to determine how bleeding events impact the subsequent mortality in the Trial to Assess Improvement in Therapeutic Outcomes by Optimizing Platelet Inhibition With Prasugrel--Thrombolysis in Myocardial Infarction 38 (TRITON-TIMI 38).

METHODS AND RESULTS

Multivariable Cox regression analyses adjusted for treatment, baseline, and procedural variables were used to determine the predictors for serious (TIMI major or minor) bleeding. To analyze the hazard ratio and time dependency of bleeding on mortality, we used iterative day-to-day landmark analyses after the bleed. From the 13 420 patients with acute coronary syndromes included in this analysis, 534 (4.0%) experienced a serious bleeding event. Variables with the highest strength of association with risk of serious bleeding were female sex, use of a glycoprotein IIb/IIIa inhibitor, duration of intervention, age, assignment to prasugrel, regional characteristics, admission diagnosis of ST-elevation myocardial infarction, femoral access for angiography, creatinine clearance, hypercholesterolemia, and arterial hypertension. Serious bleeding was associated with a significantly increased adjusted hazard ratio of 5.84 (95% confidence interval 4.11 to 8.29) for mortality. However, the hazard ratio did not differ statistically from baseline risk by 40 days after the bleeding event.

CONCLUSIONS

The major predictors of serious bleeding were a combination of patient and procedural characteristics and antiplatelet therapies. Although serious bleeding was strongly associated with mortality within the first month of the bleeding event, this association was not significant beyond 40 days.

CLINICAL TRIAL REGISTRATION INFORMATION

http://www.clinicaltrial.gov. Unique identifier NCT00097591.

Predictors of the first heart failure hospitalization in patients who are stable survivors of myocardial infarction complicated by pulmonary congestion and/or left ventricular dysfunction: a VALIANT study

AIMS

We sought to assess the incidence of and prognostic factors for heart failure (HF) hospitalization among survivors of high-risk acute myocardial infarction (MI).

METHODS AND RESULTS

We assessed the risk of an initial hospitalization for HF in 11 040 stable MI patients (no major non-fatal cardiovascular events or deaths within 45 days of randomization) without a prior history of HF enrolled in the VALIANT trial. Multivariable models were developed to identify independent predictors of HF and HF or cardiovascular death. Of 11 040 stable post-MI patients, 1139 (10.3%) developed HF during the median 25-month follow-up at a rate of approximately 3.4% per year. Most patients, 824 (72.3%), did not have a symptomatic recurrent MI between randomization and the onset of HF. The most important predictors of HF were older age, antecedent diabetes, prior MI before index MI, and reduced renal function. HF markedly increased the risk of death [HR(hazard ratio) 8.22; 95% CI(confidence interval), 7.49-9.01].

CONCLUSION

HF post high risk-MI occurs in a time-dependent fashion and is usually not directly related to re-infarction. Patients who experience HF beyond the acute phase have increased mortality. Long-term survivors of high-risk MI should be followed closely and treated aggressively beyond the acute MI period.

Mortality and morbidity remain high despite captopril and/or Valsartan therapy in elderly patients with left ventricular systolic dysfunction, heart failure, or both after acute myocardial infarction: results from the Valsartan in Acute Myocardial Infarction Trial (VALIANT)

BACKGROUND

The elderly constitute an increasing proportion of acute myocardial infarction patients and have disproportionately high mortality and morbidity. Those with heart failure or impaired left ventricular left ventricular function after acute myocardial infarction have high complication and mortality rates. Little is known about outcomes with contemporary therapies in these patients.

METHODS AND RESULTS

The Valsartan in Acute Myocardial Infarction Trial (VALIANT) randomized 14,703 patients with heart failure and/or left ventricular ejection fraction <40% to receive captopril, valsartan, or both. Mortality and a composite end point, including cardiovascular mortality, readmission for heart failure, reinfarction, stroke, and resuscitated cardiac arrest, were compared for the age groups of <65 (n=6988), 65 to 74 (n=4555), 75 to 84 (n=2777), and > or =85 (n=383) years. With increasing age, 3-year mortality almost quadrupled (13.4%, 26.3%, 36.0%, and 52.1%, respectively), composite end-point events more than doubled (25.2%, 41.0%, 52.3%, and 66.8%), and hospital admissions for heart failure almost tripled (12.0%, 23.1%, 31.3%, and 35.4%). Outcomes did not differ between the 3 study treatments in any age group. Adverse events associated with captopril and valsartan were more common in the elderly and in patients receiving combination therapy. With increasing age, use of aspirin, beta-blockers, and statins declined, and use of digoxin, calcium-channel blockers, and non-potassium-sparing diuretics increased. On 3-year multivariable analysis, each 10-year age increase was associated with a hazard ratio of 1.49 (95% CI, 1.426 to 1.557; P<0.0001) for mortality and an odds ratio of 1.38 (95% CI, 1.31 to 1.46; P<0.0001) for readmission with heart failure.

CONCLUSIONS

Outcomes remained poor in elderly patients with heart failure and/or impaired left ventricular systolic function after acute myocardial infarction, although most received beta-blockers and all received an ACE inhibitor and/or an angiotensin receptor blocker. Better therapies and increased use of aspirin, beta-blockers, and statins are needed in this important and increasing patient group.

Effect of glucose-insulin-potassium infusions on epicardial ECG changes and on myocardial metabolic changes after coronary artery ligation in dogs

The effect of glucose-insulin-potassium infusion (GIK) on developing myocardial infarction in dogs was evaluated, commencing infusion 30 min after coronary artery ligation (CAL). The parameters studied were: early (60 min after CAL) and late (6 and one half h after CAL) epicardial ST segment elevation, the change in Q, R, and S waves and certain myocardial metabolic determinations (glycogen, sodium, potassium, dry-wet weight ratio, adenosine triphosphate, creatine phosphate, inorganic phosphate, and lactate). 6 and one half h after coronary ligation Q wave amplitude was less, the R wave amplitude was greater and the metabolic profile in hte infarct zone was less deranged; metabolic improvement was also found in the nonischaemic zone. Sites in which early ST-segment elevation was less with GIK did not predict all the sites in which there was eventual lessened Q wave formation. R wave fall and disturbance of myocardial metabolism. This study supports others showing an effect of GIK in improving the features of developing experimental myocardial infarction. Following the rate of Q wave development in relation to the early ST segment elevation may be of value in assessing GIK effects provided that a qualitative rather than quantitative relationship between the two parameters is accepted.

The clinical assessment and management of patients with prosthetic cardiac valves: A review of current practice at the Cardiac Clinic, Groote Schuur Hospital

This review deals with the clinical assessment and management of patients with prosthetic cardiac valves. The types of prosthesis available are considered, with special reference to those which have been used frequently at Groot Schuur Hospital. The common complications encountered are described, as well as the clinical features of normally and abnormally functioning prostheses. The management of anticoagulant medication, pregnancy, infective endocarditis, systemic embolism and haemolysis in these patients is discussed. Particular emphasis is placed on the urgent referral to a cardiac department of patients with posthetic malfunction or conditions in which there is a potential for the development of malfunction.

Acquired pulmonary stenosis

A patient with acquired pulmonary stenosis due to lymphocytic lymphoma is presented. Three further patients with acquired pulmonary stenosis have been seen in our department in the past 15 years. A review of published cases reveals that there are more causes of this condition than have previously been enumerated.

Acute of fulminating myelofibrosis

Patients who run a fulminating course in association with histologically proven myelofibrosis are distinctly unusual, since the natural history of this entity is characteristically one of slow progression. Because of its rarity and proteam manifestations, acute myelofibrosis may easily go unrecognized. We report 2 such patients. In one, rapid clinical deterioration was dominated by spreading skin lesions, and in the other by refractory intravascular haemolysis. There was no splenomegaly in the first patient, and it was minimal in the second. Although it is seen in frequently, it should be emphasized that myelofibrosis may arise de novo as an acute illness in which the usual degree of splenomegaly is absent.