Publication Date:
2005-11-16
Description:
Pulmonary hypertension (PHT) is an emerging common complication of hereditary hemolytic anemias. It has been mechanistically and epidemiologically linked to intravascular hemolysis and decreased nitric oxide (NO) bioavailability. While this complication has been described in approximately 30% of adult patients with sickle cell disease and thalassemia, the prevalence of PHT in patients with paroxysmal nocturnal hemoglobinuria (PNH), an acquired disease with the highest levels of intravascular hemolysis observed, has never been determined. PNH patients frequently have symptoms consistent with both hemolysis and PHT including severe fatigue and dyspnea on exertion. Therefore, we examined for the presence of PHT in PNH and explored potential mechanisms associated with its development by measuring the ability of plasma to instantaneously consume NO using ozone-based chemiluminescence. Doppler echocardiography was performed in 24 hemolytic PNH patients to estimate pulmonary artery systolic pressures. Systolic PHT was defined by a tricuspid regurgitant jet velocity (TRV) ≥ 2.5m/s at rest. Eleven (46%) patients had elevated pulmonary artery systolic pressures (mean TRV 2.7m/s ± 0.08) and one (4%) had severely elevated pressures (TRV 3.5m/s). Plasma from PNH patients (n=28) consumed 32.26 ± 8.74μM NO while normal subjects (n=9) consumed 2.42 ± 0.77μM NO (p=0.03). LDH levels correlated with NO consumption (p
Print ISSN:
0006-4971
Electronic ISSN:
1528-0020
Topics:
Biology
,
Medicine
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