Small heart size and premature death in 366,484 individuals with normal ejection fraction

Abstract Background In patients with preserved left ventricular ejection fraction (LVEF), small ventricular size has been associated with reduced functional capacity, but its impact on clinical outcomes is unclear. Purpose The goal of this study was to determine the relationship between small heart size and premature mortality within a large multi-centre adult patient cohort with transthoracic echocardiographic examinations. Methods We divided 366,484 individuals with LVEF ≥ 50% (including a sub-set of 279,442 individuals with high-normal LVEF ≥ 60%) by sex and increasing quartiles for LV end-diastolic volume (LVEDV), LVEDV indexed to body surface area (LVEDVi) and LV end-diastolic diameter to assess associations with 5-year mortality through linkage with the National Death Index. Results During 2-million person-years of follow-up, 65,241 deaths occurred. Increasing LV chamber size was associated with reduced odds of 5-year all-cause mortality, particularly for higher LVEF. As compared with the larger quartiles, the smallest cardiac size quartiles were associated with higher 5-year all-cause mortality, even after adjusting for age (Figure 1). The smallest LVEDVi quartile was associated with a 14% and 18% higher odds of 5-year all-cause mortality for males and females, respectively, with a greater effect with high-normal LVEF. For cardiovascular-related mortality, females in the smallest quartile for LVEDVi had a 17% increased odds of mortality, which increased to 30% in those with LVEF was ≥ 60%. In men, there was no significant association between smallest cardiac size and cardiovascular-related mortality. Conclusions In individuals with normal LVEF, small ventricular size is associated with increased mortality, particularly among females and those with higher LVEF.