QRS duration (QRSd) criteria for device therapy in heart failure (HF) were derived from predominantly white populations and ethnic differences are poorly understood.
We compared the association of QRSd with ejection fraction (EF) and outcomes between 839 Singaporean Asian and 11 221 Swedish white patients with HF having preserved EF (HFPEF)and HF having reduced EF (HFREF) were followed in prospective population-based HF studies.
Compared with whites, Asian patients with HF were younger (62 vs 74 years, p120 ms it was 52%; HR for 10 ms increase of QRSd was 1.04 (1.03 to 1.06), p