[Studies of hyperkinetic circulatory state in chronic anemia]

To clarify the hemodynamics of anemia, 28 patients with iron deficiency anemia were investigated in respect to their parameters of left ventricular (LV) systolic and diastolic function. The subjects were categorized in three groups: 1) patients (pts) with severe anemia, whose hemoglobin (Hb) concentration was less than 7 g/dl (N = 7); 2) pts with moderate anemia, whose Hb concentration was between 7 and 10 g/dl (N = 13): and 3) pts with mild anemia whose Hb concentration was between 10 and 12 g/dl (N = 8). Changes in hemodynamic parameters were observed before and after treatment in 14 subjects. These results were compared with those of normal subjects (N = 11). In the anemic patients, LV stroke volume (SV), and heart rate both increased. An increase in SV was accompanied by an increase in LV preload (LV diastolic diameter = LVDd by M-mode echocardiography) and an increase in the Doppler parameters of early diastolic filling (peak velocity in the rapid filling phase, acceleration rate, and deceleration rate). SV correlated roughly with LVDd (r = 0.44, p less than 0.05). In addition, the indices of LV contractility as measured by the pulsed Doppler method (ET/PEP) and by M-mode echocardiography (mVcf) also increased. These factors which contributed to hyperkinetic circulation were restored as the anemia improved. It was concluded that an increase in SV is an important determinant of high cardiac output in chronic anemia, because it parallels the severity of anemia. The change in SV is preload-dependent, and is suspected of being LV contractility-dependent.