Is mild asymptomatic left ventricular systolic dysfunction always predictive of adverse events in high-risk populations? Insights from the DAVID-Berg study

Background: Mild asymptomatic left ventricular systolic dysfunction (ALVSD) may be associated with incident heart failure (HF). However, this gray zone group needs incremental risk refinement. We hypothesized that diastolic dysfunction (DD) may refine HF and death risk prediction in mild ALVSD. Methods and results: Among 4047 subjects aged ≥55/≤80 years followed by 10 general practitioners in northern Italy, the DAVID-Berg study prospectively enrolled 623 asymptomatic outpatients at increased risk for HF. Baseline evaluation included clinical visit, N-terminal pro B-type natriuretic peptide, and echocardiogram. Based on left ventricular ejection fraction (LVEF) and DD, subjects were classified as: control group (normal LVEF, n = 459, 76%), mild ALVSD (LVEF ≥40%/<53%) without DD (n = 89, 15%) and with DD (n = 54, 9%). Subjects with LVEF <40% or without full echocardiographic data were excluded from the analysis (n = 21). Mean age of the population was 69 ±7 years, 56% were men, mostly hypertensive, mean LVEF was 61%. During a median follow-up of 5.7 years, 88 subjects (15%) experienced HF/death events (59 HF events and 29 deaths). Compared to the control group, mild ALVSD was associated with a higher risk of incident HF/death (hazard ratio 1.80, 95% confidence interval 1.10–2.93, adjusted P = 0.019) according to the Cox proportional hazards model. However, this higher risk was present only in subjects with combined DD (P = 0.005) and not in those without it (P = 0.30). Results were consistent even considering the individual components of the primary outcome. Conclusion: In a high-risk population, an echocardiographic exam is normally performed to assess systolic dysfunction. Our data underline the importance of also relying on DD to risk stratify mild ALVSD. Mild ALVSD might be a predictor of adverse events mainly in subjects with combined DD, though further studies are needed to confirm these results.