Successful treatment of pulmonary hypertension following hematopoietic stem cell transplant with a single oral tadalafil: a case report.

A 46-year-old man who had undergone hematopoietic stem cell transplant twice because of acute lymphoblastic leukemia with recurrence presented with dyspnea, leading to a diagnosis of pulmonary arterial hypertension which was quickly and effectively treated with the phosphodiesterase type 5 inhibitor tadalafil. To our knowledge, pulmonary arterial hypertension related to hematologic malignancies requiring hematopoietic stem cell transplant is rarely reported. Importantly, the present case suggests that early diagnosis and treatment with a pulmonary vasodilator, such as tadalafil, can greatly decrease pulmonary vascular resistance in patients with severe pulmonary arterial hypertension after hematopoietic stem cell transplant and can then improve other symptoms. Accordingly, pulmonary vascular disease should be considered if respiratory symptoms develop following hematopoietic stem cell transplant, because treatment with pulmonary vasodilator may lead to significant improvement in pulmonary arterial hypertension.

Genomewide RNA expression profiling in lung identifies distinct signatures in idiopathic pulmonary arterial hypertension and secondary pulmonary hypertension.

Idiopathic pulmonary arterial hypertension (PAH) is a life-threatening condition characterized by pulmonary arteriolar remodeling. This investigation aimed to identify genes involved specifically in the pathogenesis of PAH and not other forms of pulmonary hypertension (PH). Using genomewide microarray analysis, we generated the largest data set to date of RNA expression profiles from lung tissue specimens from 1) 18 PAH subjects and 2) 8 subjects with PH secondary to idiopathic pulmonary fibrosis (IPF) and 3) 13 normal subjects. A molecular signature of 4,734 genes discriminated among these three cohorts. We identified significant novel biological changes that were likely to contribute to the pathogenesis of PAH, including regulation of actin-based motility, protein ubiquitination, and cAMP, transforming growth factor-beta, MAPK, estrogen receptor, nitric oxide, and PDGF signaling. Bone morphogenic protein receptor type II expression was downregulated, even in subjects without a mutation in this gene. Women with PAH had higher expression levels of estrogen receptor 1 than normal women. Real-time quantitative PCR confirmed differential expression of the following genes in PAH relative to both normal controls and PH secondary to IPF: a disintegrin-like and metalloprotease with thrombospondin type 1 motif 9, cell adhesion molecule with homology to L1CAM, cytochrome b(558) and beta-polypeptide, coagulation factor II receptor-like 3, A-myb myeloblastosis viral oncogene homolog 1, nuclear receptor coactivator 2, purinergic receptor P2Y, platelet factor 4, phospholamban, and tropomodulin 3. This study shows that PAH and PH secondary to IPF are characterized by distinct gene expression signatures, implying distinct pathophysiological mechanisms.

Impact of four times daily dosing of oral treprostinil on tolerability and daily dose achieved in pulmonary hypertension.

Oral treprostinil (TRE) is a prostacylin that is approved for the treatment of patients with pulmonary arterial hypertension (PAH). Dosing is approved for two or three times daily (t.i.d.); however, adverse effects, including gastrointestinal-related symptoms, may limit the ability to reach optimal doses. We report our experience with a four times daily (q.i.d.) regimen of oral TRE for goal-directed therapy of PAH. We describe three patients that were transitioned from infusion or inhaled TRE to oral TRE with initial t.i.d. dosing over a four-day hospital stay. All patients were subsequently further dose-adjusted in the outpatient setting; however, adverse effects limited additional up-titration despite persistent dyspnea. In a carefully monitored outpatient setting, patients were switched from t.i.d. to q.i.d. dosing of oral TRE. All three patients were successfully dosed q.i.d., having achieved a higher total daily dose compared with a t.i.d. dose regimen. Furthermore, patients were able to maintain functional class II symptoms with mitigation of adverse effects using the q.i.d. dose regimen.

Oral treprostinil for the treatment of pulmonary arterial hypertension in patients transitioned from parenteral or inhaled prostacyclins: case series and treatment protocol.

Oral treprostinil (TRE) is a prostacylin approved for the management of pulmonary arterial hypertension (PAH). Few data exist to guide the use of oral TRE as a replacement for parenteral or inhaled prostacyclins. Therefore, the purpose of this report was to describe our experience with oral TRE to transition patients from parenteral or inhaled TRE. We describe a case series of patients admitted for a 4-day hospital stay to transition from parenteral or inhaled TRE. Appropriate criteria for transition included stable patients with improved symptoms/functional capacity, patients who could not tolerate intravenous prostacyclin due to infection or subcutaneous prostacyclin due to pain, and patient preference for transition. The dosing protocol for transition is described. A total of 9 patients generally representative of a typical PAH demographic and background medical therapy were included. Patients were initiated at either 0.5 or 1 mg 3 times daily and discharged on a median dose of 8 mg 3 times daily. Our protocol resulted in 6 of 9 patients who successfully transitioned at a median follow-up of 47 weeks. Two patients had to return to their previous prostacyclin therapy based on the presence of clinical worsening and adverse events (n = 1) and adverse events alone (n = 1). Another patient discontinued therapy due to plans for hospice care. Oral TRE may serve an important role in prostacyclin transitions in carefully selected, stable patients who receive background oral therapy for PAH.

The beta1-adrenergic receptor mediates the pharmacogenetic interaction of the ACE D allele and beta-blockers.

The role of beta-receptor selectivity for the interaction between the angiotensin-converting enzyme (ACE) insertion/deletion polymorphism and beta-blocker therapy was investigated in 479 subjects with left ventricular dysfunction. Subjects were separated into no beta-blocker, beta1 -selective, and nonselective beta-blocker treatment groups. The D allele adversely affected transplant-free survival for subjects not on beta-blockers (p= 0.004). Treatment with selective beta1-blockers eliminated the impact of the D allele (p= 0.51) in a manner similar to nonselective beta1,2-blockers (p= 0.80). Treatment with beta1-blockers was sufficient to eliminate the adverse impact of the ACE D allele, suggesting this pharmacogenetic interaction is mediated through the beta1-receptor.