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

Abstract

Rationale: Although pulmonary hypertension (PH) is a common complication of sickle cell disease (SCD) associated with high mortality, there exist few data characterizing hemodynamics and cardiopulmonary function in this population. Objectives: To characterize hemodynamics and cardiopulmonary function in patients with SCD with and without PH. Methods: Patients with SCD with PH (n ϭ 26) were compared with control subjects with SCD but without PH (n ϭ 17), matched for age, hemoglobin levels, and fetal hemoglobin levels. Measurements and Main Results: Upon catheterization, 54% of the patients with PH had pulmonary arterial hypertension, and 46% had pulmonary venous hypertension. When compared with control subjects, patients with PH exhibited lower six-minute-walk distance (435 Ϯ 31 vs. 320 Ϯ 20 m, p ϭ 0.002) and oxygen consumption (50 Ϯ 3% vs. 41 Ϯ 2% of predicted, p ϭ 0.02), and also had mild restrictive lung disease and more perfusion abnormalities on radionuclide lung scans. The six-minute-walk distance in this population inversely correlated with tricuspid regurgitant jet velocity (r ϭ Ϫ0.55, p Ͻ 0.001), and mean pulmonary artery pressure (r ϭ Ϫ0.57, p Ͻ 0.001), and directly correlated with maximal oxygen consumption (r ϭ 0.49, p ϭ 0.004), even after adjustment for hemoglobin, supporting an independent contribution of increasing pulmonary artery pressures to loss of exercise capacity. Conclusions: Patients with SCD-associated PH have both pulmonary arterial and venous PH associated with severe limitations in exercise capacity, likely compounded by interstitial lung fibrosis and severe anemia. These data support the use of the six-minute-walk distance as an index of PH and cardiopulmonary function in patients with SCD.Keywords: sickle cell disease; pulmonary hypertension; six-minute walk; hemodynamics; echocardiogram Pulmonary arterial hypertension is an increasingly recognized complication of chronic hereditary and acquired hemolytic anemias, including sickle cell disease (SCD), thalassemia intermedia and major, paroxysmal nocturnal hemoglobinuria, hereditary spherocytosis and stomatocytosis, microangiopathic hemolytic anemias, pyruvate kinase deficiency, alloimmune hemolytic anemia, and possibly malaria (1, 2). In addition, certain conditions AT A GLANCE COMMENTARY Scientific Knowledge on the SubjectPulmonary hypertension is an emerging complication of sickle cell disease with high mortality. There are few data characterizing hemodynamics and cardiopulmonary function in this population. What This Study Adds to the FieldPatients with sickle cell disease-associated pulmonary hypertension have both pulmonary arterial and venous pulmonary hypertension associated with severe limitations in exercise capacity, likely compounded by interstitial lung fibrosis and severe anemia.are associated with intravascular hemolysis, and consequently there is the potential risk for the development of pulmonary hypertension, such as schistosomiasis (3, 4), and iatrogenic hemolysis from mechanical heart valves (5, 6), left ventricula...

Pulmonary Complications of Sickle Cell Disease

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Cellular, Pharmacological, and Biophysical Evaluation of Explanted Lungs from a Patient with Sickle Cell Disease and Severe Pulmonary Arterial Hypertension

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Uric Acid as a Potential Biomarker of Pulmonary Arterial Hypertension in Patients with Sickle Cell Disease

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