Comparison of Characteristics and Outcomes of Asymptomatic Versus Symptomatic Left Ventricular Dysfunction in Subjects 65 Years Old or Older (from the Cardiovascular Health Study)

Although asymptomatic left ventricular (LV) systolic dysfunction (ALVSD) is common, its phenotype and prognosis for incident heart failure (HF) and mortality are insufficiently understood. Echocardiography was done in 5,649 participants in the Cardiovascular Health Study (age 73.0 ± 5.6 years, 57.6% women). The clinical characteristics and cardiovascular risk factors of the participants with ALVSD were compared to those with normal LV function (ejection fraction ≥55%) and with symptomatic LV systolic dysfunction (SLVSD; ejection fraction <55% and a history of HF). Cox proportional hazards models were used to estimate the risk of incident HF and mortality in those with ALVSD. Also, comparisons were made among the LV ejection fraction subgroups using previously validated cutoff values (<45% and 45% to 55%), adjusting for the demographic and cardiovascular disease risk factors. Those with ALVSD (7.3%) were more likely to have cardiovascular risk factors than those in the reference group (without LV dysfunction or symptomatic HF) but less likely than those with SLVSD. The HF rate was 24 occurrences per 1,000 person-years in the reference group and 57 occurrences per 1,000 person-years in those with ALVSD. The HF rate was 45 occurrences per 1,000 person-years for those with ALVSD and mildly impaired LV dysfunction and 93 occurrences per 1,000 person-years for those with ALVSD and moderate to severe LV dysfunction. The mortality rate was 51 deaths per 1,000 person-years in the reference group, 90 deaths per 1,000 person-years in the ALVSD group, and 156 deaths per 1,000 person-years in the SLVSD group. Adjusting for covariates, compared to the reference group, ALVSD was associated with an increased risk of incident HF (hazard ratio 1.60, 95% confidence interval 1.35 to 1.91), cardiovascular mortality (hazard ratio 2.13, 95% confidence interval 1.81 to 2.51), and all-cause mortality (hazard ratio 1.46, 95% confidence interval 1.29 to 1.64). In conclusion, subjects with ALVSD are characterized by a greater prevalence of cardiovascular risk factors and co-morbidities than those with normal LV function and without HF. However, the prevalence is lower than in those with SLVSD. Patients with ALVSD are at an increased risk of HF and mortality, particularly those with greater severity of LV impairment.