Hemodynamic Studies in Sickle Cell Anemia

Abstract

Hemodynamic studies in 13 unselected patients with sickle cell anemia are reported. Twelve of these patients were also studied during mild exercise. The cardiac output at rest was elevated in all and rose significantly with exercise in 9 of the 12 patients. The importance of the increased percentage extraction of oxygen by the tissues in modifying the response of the cardiac output is discussed. The similarity of the response to exercise in the majority of these chronically anemic patients compared with the normal response is described. Included in this series is one case with secondary cor pulmonale and one case of concurrent rheumatic heart disease.

Hemodynamic and Functional Assessment of Patients with Sickle Cell Disease and Pulmonary Hypertension

“…As previously reported (12,33), patients with SCD without pulmonary hypertension have low pulmonary vascular resistance values (68.3 dyne · s · cm Ϫ5 ), whereas this value is 206.1 dyne · second · cm Ϫ5 in subjects with SCD and pulmonary hypertension.…”

“…In our recently completed prospective study of mortality in patients with SCD and pulmonary hypertension, only 13 of 195 patients had evidence of right-heart failure (right atrial pressure Ͼ 15 mm Hg), and many of the patients who died had tricuspid regurgitant jet velocities of 2.5 to 3.0 m/second (12). It is also important to point out that, although the degree of increase in pulmonary vascular resistance is relatively mild, it is greater than two times higher than the values observed in our patients without pulmonary hypertension and in two previous series of patients with severe anemia (33,35).…”

A Study of Cardiopulmonary Alterations in Patients With Sickle Cell Disease and Its Variants1

“…A pronounced abnormality of the diffusing capacity of the lungs, as evidenced by a gross increase in A-a gradient, was present in four patients (Nos. 1, 3,11,12). In all patients, the minute volume of ventilation remained close to normal, unaccompanied by subjective Pulmonary veno-arterial shunting The most important mechanism producing desaturation appears to have been right-to-left shunting within the pulmonary parenchyma.…”

Pulmonary Hypertension in Hemolytic Disorders

“…For instance, in resting adults subjected to acute isovolemic anemia, oxygen delivery can be maintained at hemoglobin concentrations as low as 5 g/dL, 50 a fi nding that also occurs in patients with chronic severe anemia. 51,52 From the hemodynamic standpoint, as hemoglobin level decreases, cardiac output increases, fi lling pressures tend to decrease, and systemic and pulmonary vascular resistances decrease. For instance, in studies of patients with SCD undergoing right-sided heart catheterization, the mean cardiac output and pulmonary vascular resistance for patients without PH were 10 L/min and 59 dyne/s/cm 5 , respectively ( Table 1 ).…”