Registry of atrial fibrillation in Latin America: Primary results of the LACROSS study

Atrial fibrillation (AF) affects more than 1% of the adult population but there is limited data of these patients in Latin America. A registry was conducted including patients with AF in four countries in Latin America.

LACROSS was a multicenter, prospective cohort that included and followed for 1-year patients with AF at 40 sites across Argentina, Brazil, Colombia and Mexico from August 2020 to June 2024. Patient characteristics, concomitant medication use, and clinical outcomes are presented.

Of 2,012 patients enrolled, the median [quartiles] age was 72 [64 - 79] years, 41.1% were women, and 41.7% had permanent AF. Only 6.6% of patients had history of previous AF ablation and 14.2% had a previous cardioversion. The median CHA₂DS₂-VA score was 3 [2 - 4]; median HAS-BLED score was 2 [1 - 3]. At baseline, 29.7% were not on oral anticoagulants and, of those taking anticoagulants, 9.8% were taking vitamin K antagonists and 60.7% were taking direct oral anticoagulants. The primary reason for not using an oral anticoagulant was physician judgement due to low risk of thromboembolism (26.1%). The rates/100 [95%CI] patient-years of death, stroke, hospitalization due to AF, AF ablation, cardioversion, systemic embolism, and major bleeding were 9.58 [8.20 - 11.19], 1.09 [0.69 - 1.73], 20.18 [18.13 - 22.46], 1.99 [1.41 - 2.80], 2.23 [1.62 - 3.08], 0.30 [0.13 - 0.72], and 1.09 [0.69 - 1.73]. Older age, diabetes, and renal disease were independently associated with an increased risk of mortality or stroke, while higher body mass index, dyslipidemia, and DOAC use at baseline were associated with a lower risk of death.

LACROSS represents a contemporary registry of patients with AF in Latin America. A high percentage of patients are still without prescription of oral anticoagulation and the identification of diverse gaps in this treatment should guide future interventions to improve the care of patients with AF in Latin America.

Study Registration: ClinicalTrials.gov ID NCT04456842.