sickle cell disease and pulmonary hypertension
- related: pulmonary hypertension
- tags: #literature #boards
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Treatment with hydroxyurea is recommended regardless of pre or postcapillary pulmonary hypertension.
PDE5 inhibitors can be used if there's precapillary pulmonary hypertension
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Because her mean pulmonary arterial pressure exceeds 20 mm Hg, this patient meets criteria for pulmonary hypertension, which is present in up to approximately 10% of individuals with sickle cell disease and is associated with worsened mortality. Causes of pulmonary hypertension associated with sickle cell disease are precapillary disease that is pathologically similar to idiopathic pulmonary arterial hypertension (approximately 20%-50% of cases), left atrial hypertension due to diastolic dysfunction (approximately 10%-30% of cases), and combined preand postcapillary processes (approximately 30%-50% of cases). This patient’s right heart catheterization reveals pulmonary hypertension with elevated pulmonary capillary wedge pressure and normal pulmonary vascular resistance; these findings are diagnostic of left atrial hypertension and pulmonary venous hypertension without concomitant precapillary disease. Therapy with hydroxyurea, which increases the concentration of fetal hemoglobin and reduces hemolysis, is recommended for patients with sickle cell disease and pulmonary hypertension regardless of cause (choice B is correct).
Because this patient has normal pulmonary vascular resistance and no evidence of precapillary pulmonary hypertension (ie, she does not have pulmonary arterial hypertension), she is not a candidate for pulmonary arterial hypertension-specific therapies such as endothelin receptor antagonists and phosphodiesterase 5 inhibitors (choices A and C are incorrect). Pulmonary arterial hypertension-specific therapies are indicated if pulmonary arterial hypertension is diagnosed in patients with sickle cell disease. Of note, sildenafil and other phosphodiesterase 5 inhibitors generally have been avoided in patients with sickle cell disease because of the finding of increased hospitalization for acute vaso-occlusive pain crises among patients receiving sildenafil in the Pulmonary Hypertension and Sickle Cell Disease with Sildenafil Therapy (Walk-PHaSST) trial. However, other trials and case series have not demonstrated adverse effects with the use of phosphodiesterase 5 inhibitors in patients with sickle cell disease.
Anticoagulation with warfarin or other agents is not indicated in the routine treatment of diastolic dysfunction and heart failure with preserved ejection fraction, as this patient’s right heart catheterization indicates that she has (choice D is incorrect). Because sickle cell disease represents a hypercoagulable state, long-term anticoagulation can be considered if VTE is documented and the patient is at low risk for bleeding; however, this patient had no clinical evidence of VTE, and her ventilation-perfusion scan was negative.1