Limited prognostic value of left ventricular global longitudinal strain in acute heart failure: the influence of hemoglobin levels
S J Kim, S H Ann, G M Park, Y G Kim, S Park, M H Jang, S G LeeAbstract
Background and Aim
Left ventricular global longitudinal strain (LV GLS) has prognostic potential for heart failure (HF) with reduced ejection fraction (EF) (HFrEF) and HF with preserved ejection fraction (HFpEF). However, it remains unclear whether hemoglobin levels influence the prognostic value of LV GLS for all-cause mortality in acute HF (AHF).
Methods
This retrospective study evaluated patients admitted for AHF between January 2012 and December 2017. Clinical and echocardiographic data, including LV GLS, were obtained from the hospital database. The primary outcome was all-cause mortality.
Results
Of the 432 patients evaluated, 262 (60.5%) had HFrEF (EF ≤40%) and 171 (39.5%) had HFpEF (EF >40%). During a median follow-up of 44 months, 227 patients (47.0%) died. In multivariate Cox regression analysis, LV GLS was not associated with lower all-cause mortality in HFrEF (hazard ratio [HR], 1.01; 95% confidence interval [CI], 0.94-1.08, P = 0.824) or HFpEF (HR, 1.01; 95% CI, 0.97-1.06, P = 0.571). In the multivariate linear regression analysis of LV GLS in HFrEF and HFpEF, heart rate (B, -0.02; 95% CI, -0.04 to -0.00, P = 0.015 vs. B, -0.06; 95% CI, -0.09 to -0.02, P = 0.001) and hemoglobin level (B, -0.16; 95% CI, -0.30 to -0.01, P = 0.037 vs. B, -0.48; 95% CI, -0.81 to -0.14, P = 0.005) were negatively associated with LV GLS after adjustment for traditional confounders (Table 1). Restricted cubic spline curves showed that the all-cause mortality risk was not associated with heart rate (Figure 2A) but increased when the hemoglobin level was <12 g/dL (Figure 2B).
Conclusion
In patients with AHF, LV GLS was not associated with all-cause mortality in HFrEF and HFpEF. LV GLS is at least equivalent if not slightly negatively associated with hemoglobin levels, and decreased hemoglobin was associated with increased all-cause mortality. Further large-scale studies should investigate whether hemoglobin levels attenuate the prognostic value of LV GLS for all-cause mortality in patients with AHF.Linear regression analysisFor image description, please refer to the figure legend and surrounding text.Restricted cubic spline curvesFor image description, please refer to the figure legend and surrounding text.