Atrial Fibrillation and Systemic Thromboembolism – Causal Correlation or a Message of Atrial Disease?

The correlation between atrial fibrillation (AF) and thromboembolism is well known. In 1951, Raymond Daley et al. associated the occurrence of this arrhythmia to systemic embolic events with consistent information in patients with chronic rheumatic heart disease1. In this study involving 194 patients with rheumatic heart disease who were victims of thromboembolism, with autopsy information in 39 patients, the presence of AF was demonstrated in about 90% of cases. The classic Framingham study, published in 1978, was the first large study that established this same correlation in nonrheumatic individuals, showing that individuals with AF are nearly six times more likely to have a stroke than the AF-free individuals with characteristics adjusted for sex, age and blood pressure2. The inclusion of rheumatic individuals has raised this risk to approximately 18 times. Since this important publication, several studies have corroborated these findings.