title: Severity of pulmonary hypertension during vaso-occlusive pain crisis and exercise in patients with sickle cell disease.
abstract: Pulmonary hypertension is associated with sudden death and is a risk factor for mortality in adult patients with sickle cell disease. The high mortality despite only mild-to-moderate increases in pulmonary vascular resistance remains an unresolved paradox. Accordingly, little is known about the cardiovascular effects of stressors, such as vaso-occlusive pain crisis (VOC) and exercise, which may acutely increase pulmonary pressures and impair right heart function. We therefore evaluated pulmonary artery pressures by echocardiogram in 25 patients with sickle cell disease in steady-state and during VOC, and by right heart catheterisation with exercise in a second cohort of 21 patients to determine whether pulmonary hypertension worsens during acute cardiopulmonary stress. TRV increased during VOC (P < 0.001), and the increased pulmonary pressures during VOC were associated with decreases in haemoglobin levels (P < 0.001), and increases in lactate dehydrogenase (P < 0.001) and plasma haemoglobin levels (P = 0.03). During exercise stress performed during cardiac catheterisation, mean pulmonary artery pressures (P < 0.001) and pulmonary vascular resistance increased (P < 0.001) in all subjects. These data suggest that acute elevations in pulmonary pressures during VOC or exercise may contribute to morbidity and mortality in patients with sickle cell disease.
authors.affiliation: Vascular Medicine Branch, National Heart Lung and Blood Institute, National Institutes of Health, Bethesda, MD 20892-1476, USA. robertom@nhlbi.nih.gov
authors.forename: Roberto F
authors.initials: RF
authors.lastname: Machado
authors.forename: A Kyle
authors.initials: AK
authors.lastname: Mack
authors.forename: Sabrina
authors.initials: S
authors.lastname: Martyr
authors.forename: Christopher
authors.initials: C
authors.lastname: Barnett
authors.forename: Peter
authors.initials: P
authors.lastname: Macarthur
authors.forename: Vandana
authors.initials: V
authors.lastname: Sachdev
authors.forename: Inez
authors.initials: I
authors.lastname: Ernst
authors.forename: Lori A
authors.initials: LA
authors.lastname: Hunter
authors.forename: Wynona A
authors.initials: WA
authors.lastname: Coles
authors.forename: James P
authors.initials: JP
authors.lastname: Nichols
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Kato
authors.forename: Mark T
authors.initials: MT
authors.lastname: Gladwin
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D000755:Anemia, Sickle Cell / Q000150:complications* / Q000000981:diagnostic imaging; D001794:Blood Pressure; D006328:Cardiac Catheterization; D004452:Echocardiography; D015444:Exercise; D005260:Female; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D006976:Hypertension, Pulmonary / Q000000981:diagnostic imaging / Q000209:etiology*; D007770:L-Lactate Dehydrogenase / Q000097:blood; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000000981:diagnostic imaging / Q000209:etiology*; D014652:Vascular Diseases / Q000150:complications* / Q000000981:diagnostic imaging; D014655:Vascular Resistance
chemical_list: D006454:Hemoglobins; D007770:L-Lactate Dehydrogenase