Treatment of patients with chronic thrombo embolic pulmonary hypertension: focus on riociguat

Chronic thromboembolic pulmonary hypertension (CTEPH) is a disease of the pulmonary vascular bed that is characterized by elevations in the mean pulmonary artery pressure in the setting of perfusion defects on ventilation-perfusion scan, and subsequently confirmed by pulmonary angiography. CTEPH, or World Health Organization (WHO) group 4 pulmonary hypertension, is a result of unresolved thromboembolic obstruction in the pulmonary arteries. Pulmonary endarterectomy (PEA) is the treatment of choice for CTEPH as it is a potentially curative therapy. However, up to one-third of patients are not candidates for the surgery, either due to distal and inaccessible nature of the lesions or comorbid conditions. Due to remodeling that occurs in nonobstructed pulmonary vessels, a portion of patients who have undergone PEA have residual CTEPH after the procedure, attributable to high shear stress prior to PEA. This phenomenon has led to the understanding of a so-called two-compartment model of CTEPH, opening the door to pharmacologic treatment strategies. In 2013, riociguat, a soluble guanylate cyclase stimulator, was approved in the US and Europe for the treatment of inoperable or persistent/recurrent CTEPH. This article reviews the current management of CTEPH with a focus on riociguat

Combination therapy with oral treprostinil for pulmonary arterial hypertension. A double-blind placebo-controlled clinical trial

Rationale: Oral treprostinil improves exercise capacity in patients with pulmonary arterial hypertension (PAH), but the effect on clinical outcomes was unknown. Objectives: To evaluate the effect of oral treprostinil compared with placebo on time to first adjudicated clinical worsening event in participants with PAH who recently began approved oral monotherapy. Methods: In this event-driven, double-blind study, we randomly allocated 690 participants (1:1 ratio) with PAH to receive placebo or oral treprostinil extended-release tablets three times daily. Eligible participants were using approved oral monotherapy for over 30 days before randomization and had a 6-minute-walk distance 150 m or greater. The primary endpoint was the time to first adjudicated clinical worsening event: death; hospitalization due to worsening PAH; initiation of inhaled or parenteral prostacyclin therapy; disease progression; or unsatisfactory long-term clinical response. Measurements and Main Results: Clinical worsening occurred in 26% of the oral treprostinil group compared with 36% of placebo participants (hazard ratio, 0.74; 95% confidence interval, 0.56–0.97; P = 0.028). Key measures of disease status, including functional class, Borg dyspnea score, and N-terminal pro–brain natriuretic peptide, all favored oral treprostinil treatment at Week 24 and beyond. A noninvasive risk stratification analysis demonstrated that oral treprostinil–assigned participants had a substantially higher mortality risk at baseline but achieved a lower risk profile from Study Weeks 12–60. The most common adverse events in the oral treprostinil group were headache, diarrhea, flushing, nausea, and vomiting. Conclusions: In participants with PAH, addition of oral treprostinil to approved oral monotherapy reduced the risk of clinical worsening. Clinical trial registered with www.clinicaltrials.gov (NCT01560624)

The red inmate.

Drug rash with eosinophilia and systemic symptoms (DRESS) syndrome is a severe idiosyncratic drug reaction that has a long latency period. It is characterized by an extensive rash, fever, lymphadenopathy, hematologic abnormalities, hepatitis, and involvement of the kidneys, lungs, heart, or pancreas. Symptoms often start 2-6 weeks after drug initiation. The incidence of DRESS has been estimated to be between 1 in 1,000 and 1 in 10,000 drug exposures. It has a mortality rate of 10-20%, with most fatalities resulting from liver failure. A 21 year-old male inmate presented with nausea, vomiting, epigastric pain, rash and fever. The patient had earned the nickname “Red” due to his appearance. On his initial arrival to the intensive care unit, patient was alert and only oriented to self, but not to place or time. Physical examination showed diffuse blanching erythematous patch throughout his body and increased work of breathing. His laboratory studies showed lactic acidosis, acute renal and liver failure as well as leukocytosis with atypical lymphocytes, eosinophilia and thrombocytopenia. Computer tomography showed axillary and abdominal lymphadenopathy. Differential diagnosis included septic shock, anaphylactic shock, severe drug reaction, acute fulminant liver failure, and lymphoblastic lymphoma as his sister was recently diagnosed with the latter. Mechanical ventilation and broad spectrum antibiotics were initiated along with intravenous fluid and vasopressor for suspected septic shock. Peripheral smear showed leukocytosis with left shift and 13% atypical lymphocytes; however, the flow cytometry was negative. Skin biopsy was done demonstrating superficial dermal edema with focal keratinocyte necrosis and chronic inflammation with pigment incontinence suggestive of cutaneous hypersensitivity reaction, but no lymphocyte atypia or intravascular lymphoma was seen. Liver biopsy was undertaken which was suggestive of drug-induced hepatic toxicity. Records from the correctional facility revealed new initiation of sulfasalazine for suspected inflammatory colitis. Sulfasalazine was thought to be the likely cause of DRESS syndrome in this patient. He improved with supportive care and was discharged back to the correction facility. The international registry of severe cutaneous adverse reaction (RegiSCAR) criteria for the diagnosis of DRESS includes fever, lymphadenopathy at a minimum of 2 sites, involvement of at least 1 internal organ and abnormalities in lymphocytes, eosinophil and platelet counts. The idiosyncratic presentation and the non-specific diagnostic criteria make diagnosis of DRESS challenging particularly in the critically-ill patients with multi-system organ failure. This case demonstrates these challenges and the importance of obtaining detailed medication history

Treatment of patients with chronic thrombo embolic pulmonary hypertension: focus on riociguat

Chronic thromboembolic pulmonary hypertension (CTEPH) is a disease of the pulmonary vascular bed that is characterized by elevations in the mean pulmonary artery pressure in the setting of perfusion defects on ventilation-perfusion scan, and subsequently confirmed by pulmonary angiography. CTEPH, or World Health Organization (WHO) group 4 pulmonary hypertension, is a result of unresolved thromboembolic obstruction in the pulmonary arteries. Pulmonary endarterectomy (PEA) is the treatment of choice for CTEPH as it is a potentially curative therapy. However, up to one-third of patients are not candidates for the surgery, either due to distal and inaccessible nature of the lesions or comorbid conditions. Due to remodeling that occurs in nonobstructed pulmonary vessels, a portion of patients who have undergone PEA have residual CTEPH after the procedure, attributable to high shear stress prior to PEA. This phenomenon has led to the understanding of a so-called two-compartment model of CTEPH, opening the door to pharmacologic treatment strategies. In 2013, riociguat, a soluble guanylate cyclase stimulator, was approved in the US and Europe for the treatment of inoperable or persistent/recurrent CTEPH. This article reviews the current management of CTEPH with a focus on riociguat

Inhaled Iloprost for Chronic Thromboembolic Pulmonary Hypertension (CTEPH) During Pregnancy: A Case Report

Chronic thromboembolic pulmonary hypertension (CTEPH) is a subset of pulmonary hypertension caused by acute and recurrent pulmonary emboli. Pulmonary thromboendarterectomy is the treatment of choice, but 10-50% of patients are ineligible for this procedure. We describe the case of a 25-year-old, morbidly obese (228-kg, body mass index 83.5 kg/m(2) ) pregnant woman (G3 P2 ) who presented at 24 weeks\u27 gestation; bilateral pulmonary angiography revealed filling defects and confirmed the diagnosis of CTEPH. The patient was evaluated and deemed to present too high of a risk for pulmonary thromboendarterectomy, so a multidisciplinary team initiated medical therapy. Sildenafil 20 mg orally 3 times/day was started at week 24 of gestation, and inhaled iloprost was added at 26 weeks and titrated to 5 µg inhaled every 2 hrs in order to optimize hemodynamic status prior to a cesarean section delivery scheduled to be performed 6 weeks later. At 32 weeks of gestation, the patient\u27s pulmonary arterial systolic pressure was 77 mm Hg, right atrial pressure was 15 mm Hg, and pulmonary capillary wedge pressure of 16 mm Hg, and a healthy 1741-g male infant was delivered by cesarean section. The patient was transferred back to the medical intensive care unit in stable condition and discharged home 9 days following the procedure. Pharmacotherapeutic strategies for patients with CTEPH who become pregnant are limited to phosphodiesterase type 5 inhibitors and prostacyclin analog therapies due to the teratogenicity of the other drug classes used to treat the disorder (endothelin receptor antagonists and soluble guanylate cyclase stimulators). To our knowledge, this is the first case report of inhaled iloprost use in addition to oral sildenafil to improve patient symptomatology and hemodynamics during the peripartum period of a young pregnant patient with inoperable CTEPH. This drug therapy was used safely, with no noted adverse effects to the newborn or to the patient

Inhaled Iloprost for Chronic Thromboembolic Pulmonary Hypertension (CTEPH) During Pregnancy: A Case Report

Chronic thromboembolic pulmonary hypertension (CTEPH) is a subset of pulmonary hypertension caused by acute and recurrent pulmonary emboli. Pulmonary thromboendarterectomy is the treatment of choice, but 10-50% of patients are ineligible for this procedure. We describe the case of a 25-year-old, morbidly obese (228-kg, body mass index 83.5 kg/m(2) ) pregnant woman (G3 P2 ) who presented at 24 weeks\u27 gestation; bilateral pulmonary angiography revealed filling defects and confirmed the diagnosis of CTEPH. The patient was evaluated and deemed to present too high of a risk for pulmonary thromboendarterectomy, so a multidisciplinary team initiated medical therapy. Sildenafil 20 mg orally 3 times/day was started at week 24 of gestation, and inhaled iloprost was added at 26 weeks and titrated to 5 µg inhaled every 2 hrs in order to optimize hemodynamic status prior to a cesarean section delivery scheduled to be performed 6 weeks later. At 32 weeks of gestation, the patient\u27s pulmonary arterial systolic pressure was 77 mm Hg, right atrial pressure was 15 mm Hg, and pulmonary capillary wedge pressure of 16 mm Hg, and a healthy 1741-g male infant was delivered by cesarean section. The patient was transferred back to the medical intensive care unit in stable condition and discharged home 9 days following the procedure. Pharmacotherapeutic strategies for patients with CTEPH who become pregnant are limited to phosphodiesterase type 5 inhibitors and prostacyclin analog therapies due to the teratogenicity of the other drug classes used to treat the disorder (endothelin receptor antagonists and soluble guanylate cyclase stimulators). To our knowledge, this is the first case report of inhaled iloprost use in addition to oral sildenafil to improve patient symptomatology and hemodynamics during the peripartum period of a young pregnant patient with inoperable CTEPH. This drug therapy was used safely, with no noted adverse effects to the newborn or to the patient

Transitioning Parenteral or Inhaled Treprostinil to Oral Treprostinil Diolamine: Case Series and Review of the Literature

Treprostinil diolamine is the first oral dosage preparation of a prostacyclin analogue for use in treatment naive pulmonary arterial hypertension (PAH). This case series and review of the available literature describes the experience of patients with PAH receiving treprostinil by intravenous (IV), subcutaneous (SQ), or inhalation route who were transitioned to treprostinil diolamine. At our institution, 3 patients were transitioned to treprostinil diolamine who received treprostinil administered by each of the alternative routes: IV, SQ, and inhalation. All patients tolerated the transition without significant worsening of disease end points. In the literature, 5 additional reports representing 48 patients were transitioned to treprostinil diolamine from an alternate route of administration. A majority (92%) of patients were hospitalized during the cross-titration phase and tolerated the transition without changes in disease markers or significant adverse effect. Six (13%) patients required reinitiation of parenteral therapy due to clinical decline. The most common dosing frequency utilized for treprostinil diolamine was 3 times per day. In patients with stable PAH receiving parenteral or inhaled treprostinil, a transition to treprostinil diolamine was a safe approach in a highly select population meeting clinical end points. Additional studies are required to further describe this clinical strategy before accepted in clinical practice

Transitioning Parenteral or Inhaled Treprostinil to Oral Treprostinil Diolamine: Case Series and Review of the Literature

Treprostinil diolamine is the first oral dosage preparation of a prostacyclin analogue for use in treatment naive pulmonary arterial hypertension (PAH). This case series and review of the available literature describes the experience of patients with PAH receiving treprostinil by intravenous (IV), subcutaneous (SQ), or inhalation route who were transitioned to treprostinil diolamine. At our institution, 3 patients were transitioned to treprostinil diolamine who received treprostinil administered by each of the alternative routes: IV, SQ, and inhalation. All patients tolerated the transition without significant worsening of disease end points. In the literature, 5 additional reports representing 48 patients were transitioned to treprostinil diolamine from an alternate route of administration. A majority (92%) of patients were hospitalized during the cross-titration phase and tolerated the transition without changes in disease markers or significant adverse effect. Six (13%) patients required reinitiation of parenteral therapy due to clinical decline. The most common dosing frequency utilized for treprostinil diolamine was 3 times per day. In patients with stable PAH receiving parenteral or inhaled treprostinil, a transition to treprostinil diolamine was a safe approach in a highly select population meeting clinical end points. Additional studies are required to further describe this clinical strategy before accepted in clinical practice