Relationship between spleen size and exercise tolerance in advanced heart failure patients with a left ventricular assist device

OBJECTIVE: Spleen volume increases in patients with advanced heart failure (HF) after left ventricular assist device (LVAD) implantation. However, the relationship between spleen volume and exercise tolerance (peak oxygen consumption [VO(2)]) in these patients remains unknown. In this exploratory study, we enrolled 27 patients with HF using a LVAD (median age: 46 years). Patients underwent blood testing, echocardiography, right heart catheterization, computed tomography (CT), and cardiopulmonary exercise testing. Spleen size was measured using CT volumetry, and the correlations/causal relationships of factors affecting peak VO(2) were identified using structural equation modeling. RESULTS: The median spleen volume was 190.0 mL, and peak VO(2) was 13.2 mL/kg/min. The factors affecting peak VO(2) were peak heart rate (HR; β = 0.402, P = .015), pulmonary capillary wedge pressure (PCWP; β = − 0.698, P = .014), right ventricular stroke work index (β = 0.533, P = .001), blood hemoglobin concentration (β = 0.359, P = .007), and spleen volume (β = 0.215, P = .041). Spleen volume correlated with peak HR, PCWP, and hemoglobin concentration, reflecting sympathetic activity, cardiac preload, and oxygen-carrying capacity, respectively, and was thus related to peak VO(2). These results suggest an association between spleen volume and exercise tolerance in advanced HF. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s13104-022-05939-y.