Stroke risk in rheumatic heart disease

Cardiologists’ perception of the risk of stroke in rheumatic heart disease (RHD) is influenced more by anecdote and opinion than by the evidence.1 Despite data indicating a similar, if not a lower risk of stroke, even among the potentially highest-risk patients with RHD (those with mitral stenosis (MS) and atrial fibrillation (AF)),1 there is a pervasive belief that they may be at the ‘highest risk of thromboembolism’.2 As a consequence, in current practice, any patient with significant valvular heart disease and AF (valvular AF) becomes a candidate for long-term oral anticoagulation, without further risk stratification . The perception of very high stroke risk in RHD is also reinforced by estimates of stroke burden, which are based on extrapolation from the proportion of stroke admissions who have RHD (3%–8%),3 rather than the proportion of strokes attributable to RHD in the community (1%–2%).4 Contemporary data on stroke risk in RHD are therefore needed to realign risk perceptions to reality, to aid in risk stratification and to help make decisions on long-term anticoagulation. The study by Vasconcelos and colleagues in this issue of Heart is therefore a welcome addition to the literature in this area.5 Patients with valvular AF have a risk of stroke similar to that of those with non-valvular AF. Data from the Framingham study showed that the absolute risk of stroke was 4.5 per 100 patient-years among patients with MS and AF, similar to the risk in those with non-valvular AF (4.2 per 100 patient-years).6 In passing, it is worth noting that most references …