Atrial fibrillation and stroke

Atrial fibrillation: an important stroke risk factor

Meet Professor Tatjana Potpara,  School of Medicine, Belgrade University, Serbia and co-author of the 2020 European Society of Cardiology atrial fibrillation guidelines. In this video, Professor Potpara discusses the relationship between atrial fibrillation and stroke.

Association between atrial fibrillation and stroke

Atrial fibrillation (AF) is an important risk factor for stroke. In AF, disrupted heart rhythm may cause blood to pool in the heart’s atria and form clots. If a blood clot forms, it could dislodge from the heart and travel to the brain, blocking the blood flow and causing a stroke (Figure 1). Identifying and managing AF early and effectively can help prevent AF-related stroke¹.

Figure 1. How atrial fibrillation can lead to stroke.

Epidemiology of stroke

Stroke is ranked as the second leading cause of death worldwide with an annual mortality rate of about 5.5 million. The burden of stroke not only lies in the high mortality, but also in the high morbidity, since up to 50% of survivors become chronically disabled¹⁶.

Age-adjusted stroke incidence varies from 95–290 per 1,000,000 of the European population annually¹⁷. About 1.1 million people experience a stroke in Europe each year. Transient ischaemic attacks (TIAs) are also common: the age-adjusted incidence ranged from 28–59 per 100,000 of the European population each year¹⁷.

Despite improved prevention, rapid diagnosis and prompt treatment, stroke remains common. Many stroke survivors develop serious complications and demographic changes mean that strokes and TIAs are likely to become even more common over the next few decades¹⁷.

Stroke incidence, for example, increases 100-fold between 40 and 80 years of age, while the age-adjusted incidence is 1.2–2.0 times higher in men than women, but life-expectancy is lower in males than females. Epidemiologists predict that, if current trends continue, by 2025, 1.5 million people in Europe will experience a stroke each year¹⁷.

Classification of atrial fibrillation 

Atrial fibrillation (AF) can present in several ways and correct classification can guide the choice of treatment. AF can present from a single isolated episode to a constant arrhythmia (Table 2). 

Pathophysiology of atrial fibrillation

A network of pathways influences the onset and persistence of atrial fibrillation

In any particular patient, the onset and persistence of atrial fibrillation (AF) may involve a complex network of mutually reinforcing pathogenic pathways that are influenced by age, genetic factors and acquired risk factors^2,27. For example, acute coronary syndrome (ACS), such as myocardial infarction, as well as surgery or infection seem to precipitate a third of AF cases⁸. Table 3 summaries the possible pathophysiology of different AF types, which may overlap in clinical practice¹². This section takes a deep dive into the pathophysiology of this common arrhythmia and its relationship with stroke.

Burden of atrial fibrillation

Atrial fibrillation (AF) impairs patients’ quality of life and accounts for up to 2% of healthcare budgets; stroke and hospitalisations drive the costs.

AF patients report impaired quality of life (QoL) that is independent of concomitant cardiovascular conditions¹². The impairment in QoL associated with AF can be similar to that in congestive heart failure (CHF) and reflects the symptoms of the disease and complications, such as stroke³⁵. AF’s impact on QoL may be especially marked in women, younger patients and those with comorbid conditions, such as coronary artery disease, chronic obstructive pulmonary disease (COPD), obstructive sleep apnoea or New York Heart Association (NYHA) classes II-IV CHF. Some of these factors could be modified and their presence may indicate that the patient requires a thorough QoL assessment³⁵.

Between 10% and 30% of AF patients are hospitalised annually¹²

References

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