Does antithrombotic therapy improve outcomes in patients with cardioembolic stroke?

The aim of Kristaps Jurjāns' doctoral thesis was to evaluate the effect of antithrombotic therapy* on reducing mortality and improving long-term functional outcomes in patients with cardioembolic stroke in Latvia.

The study's findings

In Latvia and other Baltic countries, cardioembolic stroke is dominated by the ischaemic stroke subtype, which has a higher prevalence than in other European countries. Patients in Latvia tend to be older and predominantly female. These patients also have a higher prevalence of comorbidities such as coronary heart disease, angina pectoris, chronic heart failure and chronic kidney disease. 

The prevalence of newly diagnosed atrial fibrillation in these patients is relatively high and its detection rate is influenced by the method of monitoring, duration and time after stroke. The high prevalence of undiagnosed atrial fibrillation, which is often asymptomatic, may contribute to the development of cryptogenic stroke. 

The use of vitamin K antagonists in patients with atrial fibrillation is complicated by an increased risk of bleeding complications. Direct-acting oral anticoagulants are safer in these patients because they cause fewer complications and bleeding events. 

The study revealed a lack of antithrombotic therapy in patients with atrial fibrillation and highlighted significant differences between practice and current clinical guidelines. The poor functional outcomes and high mortality of patients with cardioembolic stroke require further investigation. The prescription of oral anticoagulants for stroke prevention in elderly and severely disabled patients remains suboptimal, suggesting an age-related bias.

Previous studies have concluded that cardioembolic stroke is associated with higher mortality and poorer functional outcomes. However, when patients with cardioembolic stroke received appropriate antithrombotic therapy for secondary stroke prevention, their long-term mortality rates were lower and they achieved greater independence, improving long-term survival and functional outcomes. Severe neurological deficit should not be a reason to limit the use of anticoagulants. Anti-platelet therapy is not recommended because it showed only a small improvement in long-term survival and functional outcome.

Recommendations and next steps

As cardioembolic stroke, the predominant subtype of ischaemic stroke in Latvia, causes poor functional outcome and high mortality, primary and secondary prevention of arrhythmia should be promoted at national level. 

Public authorities should address the issue of reimbursement for antithrombotic drugs and provide patients with self-monitoring devices to facilitate monitoring and dose adjustment. Communication between healthcare professionals and patients should be improved by providing additional time for education on anticoagulant use and drug interactions.

Patients with irregular heartbeat should be prescribed direct-acting oral anticoagulants rather than vitamin K antagonists because of their ease of use and safety. Severe neurological deficits, patient age or frailty should not be a reason to limit the use of anticoagulants in either primary or secondary stroke prevention.

* Antithrombotic therapy covers a broader group of drugs that includes both anticoagulants and anti-platelet agents. Anti-platelet agents, such as aspirin, prevent blood platelets from sticking together and forming clots. Different drugs are used in this therapy to prevent blood clots from forming.