Cardiovascular Volume Reserve in Patients with Heart Failure and Reduced Ejection Fraction.

This study aimed to investigate the relationship between intravascular volume and intracardiac filling pressures in stable HF patients with reduced ejection fraction (HFrEF). A total of 40 HFrEF patients (LVEF 36 ± 10%) (10 subjects with a pulmonary artery catheter) underwent intravascular volume expansion with 1 L hydroxyl-ethyl-starch over 3 h with coinciding intravascular volume measurements (technetium (99 tc)-labeled red blood cell technique). Intravascular blood volume increased from 5.0 ± 1.0 L to 5.7 ± 1.0 L (p < 0.0001). No change in clinical status, echocardiographic indices, or cardiac filling pressures was noticed. Invasively measured right atrial pressure and pulmonary arterial wedge pressure increased significantly immediately after start of infusion (4 ± 2 mmHg to 8 ± 4 mmHg; p = 0.01 and 10 ± 3 mmHg to 15 ± 6 mmHg; p = 0.01, respectively), decreased afterwards, and remained stable for 3 h (6 ± 2 mmHg and 14 ± 4 mmHg, respectively). The accuracy of cardiac filling pressure estimates to predict intravascular volume expansion was low (all AUC < 0.65).