Milvexian vs Apixaban for Stroke Prevention in Atrial Fibrillation: The LIBREXIA Atrial Fibrillation Trial Rationale and Design

BACKGROUND: Direct oral anticoagulants are the standard of care for stroke prevention in eligible patients with atrial fibrillation and atrial flutter; however, bleeding remains a significant concern, limiting their use. Milvexian is an oral Factor XIa inhibitor that may offer similar anticoagulant efficacy with less bleeding risk. METHODS: LIBREXIA AF (NCT05757869) is a global phase III, randomized, double-blind, parallel-group, event-driven trial to compare milvexian with apixaban in participants with atrial fibrillation or atrial flutter. Participants are randomly assigned to milvexian 100 mg or apixaban (5 mg or 2.5 mg per label indication) twice daily. The primary efficacy objective is to evaluate if milvexian is noninferior to apixaban for the prevention of stroke and systemic embolism. The principal safety objective is to evaluate if milvexian is superior to apixaban in reducing the endpoint of International Society of Thrombosis and Hemostasis (ISTH) major bleeding events and the composite endpoint of ISTH major and clinically relevant nonmajor (CRNM) bleeding events. In total, 15,500 participants from approximately 1,000 sites in over 30 countries are planned to be enrolled. They will be followed until both 430 primary efficacy outcome events and 530 principal safety events are observed, which is estimated to take approximately 4 years. CONCLUSION: The LIBREXIA AF study will determine the efficacy and safety of the oral Factor XIa inhibitor milvexian compared with apixaban in participants with either atrial fibrillation or atrial flutter. TRIAL REGISTRATION: ClinicalTrials.gov NCT05757869

Using heart rate variability to stratify risk of obstetric patients undergoing spinal anesthesia.

In this study, we evaluated whether point correlation dimension (PD2), a measure of heart rate variability, can predict hypotension accompanying spinal anesthesia for cesarean delivery. After the administration of spinal anesthesia with bupivacaine, hypotension was defined as systolic blood pressur

Risks and benefits of combining aspirin with anticoagulant therapy in patients with atrial fibrillation: An exploratory analysis of stroke prevention using an oral thrombin inhibitor in atrial fibrillation (SPORTIF) trials

Aspirin is used in combination with anticoagulant therapy in patients with atrial fibrillation (AF), but evidence of additional efficacy is not available. We compared ischemic events and bleeding in the SPORTIF III and IV randomized trials of anticoagulation with warfarin (international normalized ratio 2-3) or fixed-dose ximelagatran. Low-dose aspirin (<100 mg/d) was allowed based on prevailing guidelines. The 14% of patients receiving aspirin more often had diabetes (27.5% vs 23%, P < .01), coronary artery disease (69% vs 41%, P < .01), previous stroke or transient ischemic attack (26% vs 20%, P < .01), and left ventricular dysfunction (41% vs 36%, P < .01). Addition of aspirin to either warfarin or ximelagatran was associated with no reduction in stroke or systemic embolism. Major bleeding occurred significantly more often with aspirin plus warfarin (3.9% per year) than with warfarin alone (2.3% per year, P < .01), aspirin plus ximelagatran (2.0% per year), or ximelagatran alone (1.9% per year). The rate of myocardial infarction with aspirin and warfarin (0.6% per year) was not significantly different from that with ximelagatran alone (1.0% per year), warfarin alone (1.0% per year), or aspirin and ximelagatran (1.4% per year). Aspirin combined with anticoagulant therapy was associated with no reduction in stroke, systemic embolism, or myocardial infarction in patients with AF. Aspirin combined with warfarin was associated with an incremental rate of major bleeding of 1.6% per year. No increased major bleeding occurred with aspirin and ximelagatran. These results suggest that the risks associated with addition of aspirin to anticoagulation in patients with AF outweigh the benefit

Reduction in First and Recurrent Cardiovascular Events with Ticagrelor Compared with Clopidogrel in the Plato Study

Background-We sought to evaluate the effect of potent platelet inhibition after acute coronary syndrome on total (ie, first and recurrent) occurrences of any of the primary outcome events (eg, cardiovascular death, myocardial infarction, and stroke) as well as on other ischemic events, such as urgent revascularization, (severe) recurrent ischemia, transient ischemic attacks, and arterial thrombotic events. Methods and Results-In the PLATelet inhibition and patient Outcomes (PLATO) study, 18 624 patients presenting with acute coronary syndromes randomly received ticagrelor (n=9333) or clopidogrel (n=9291). Cox proportional hazard models were used to calculate time to first event and hazard ratios. Total events were compared using a Poisson regression model, and time to second event or death was calculated with the Wei Lin Weissfeld method. Patients randomized to ticagrelor had 1057 total primary end point events versus 1225 for patients on clopidogrel (rate ratio, 0.86; 95% confidence interval, 0.79-0.93; P=0.003). The number of additional events was numerically lower for ticagrelor (189 versus 205; P=0.40), resulting in a hazard for time to second event/death of 0.80 (95% confidence interval, 0.70-0.90; P<0.001) and a number needed to treat of 54. For cardiovascular death/myocardial infarction/stroke/(severe) recurrent ischemia/transient ischemic attack/arterial thrombotic events, total events were fewer with ticagrelor (2030 versus 2290; rate ratio, 0.88; 95% confidence interval, 0.82-0.95; P<0.001), with fewer recurrent events with ticagrelor (740 versus 834; P=0.01) and a highly significant concurrent reduction in hazard for time to second event or death of 0.83 (95% confidence interval, 0.75-0.91; P<0.001). Recurrent PLATO major or Thrombolysis in Myocardial Infarction (TIMI) major non-coronary artery bypass graft bleeding events were infrequent and not different between the two therapies (P=0.96 and 0.38, respectively). Conclusions-In PLATO, treatment with ticagrelor compared with clopidogrel resulted in a reduction in total events, including first and subsequent recurrent cardiovascular events, when compared with clopidogrel. These types of analyses demonstrate an even greater absolute benefit of ticagrelor over clopidogrel than previously reported.WoSScopu

The efficacy of ticagrelor is maintained in women with acute coronary syndromes participating in the prospective, randomized, PLATelet inhibition and patient Outcomes (PLATO) trial

Aims The aim of this study was to assess the relationship between sex and clinical outcomes and treatment-related complications in patients with ST-elevation or non-ST-elevation acute coronary syndromes (ACS) randomized to treatment with ticagrelor or clopidogrel in the PLATelet inhibition and patient Outcomes (PLATO) trial. Methods The associations between sex subgroup and the primary composite outcomes, secondary outcomes, and major bleeding endpoints as well as interaction of sex subgroup with treatment effects were analysed using Cox proportional-hazards models. Results Sex was not significantly associated with the probability of the primary composite endpoint [adjusted hazard ratio (HR): 1.02 (0.91-1.16)], or other adverse cardiovascular endpoints. Ticagrelor was similarly more effective than clopidogrel in reducing rates of the primary endpoint in women 11.2 vs. 13.2% [adjusted HR: 0.88 (0.74-1.06)] and men 9.4 vs. 11.1% [adjusted HR: 0.86 (0.76-0.97)] (interaction P-value 0.78), all-cause death in women 5.8 vs. 6.8% [adjusted HR: 0.90 (0.69-1.16)] and men 4.0 vs. 5.7% [adjusted HR: 0.80 (0.67-0.96)] (interaction P-value 0.49), and definite stent thrombosis in women 1.2 vs. 1.4% [adjusted HR: 0.71 (0.36-1.38)] and men 1.4 vs. 2.1% [adjusted HR: 0.63 (0.45-0.89)] (interaction P-value 0.78). The treatments did not differ for PLATO-defined overall major bleeding complications in women [adjusted HR: 1.01 (0.83-1.23)] or men [adjusted HR: 1.10 (0.98-1.24)]. Sex had no significant association with these outcomes (interactions P = 0.43-0.88). Conclusion Female sex is not an independent risk factor for adverse clinical outcomes in moderate-to-high risk ACS patients. Ticagrelor has a similar efficacy and safety profile in men and women