PubMed Health⌕ Search

Biomedical subjects

H Olschewski

Publications and source records attributed to H Olschewski.

At least 19 recordsLinked to original sources

[Treatment of pulmonary arterial hypertension: prostacyclin analogs].

Prostanoids continue to be of great importance in the treatment of pulmonary hypertension (PHT). Their vasodilatory, antiproliferative, anti-inflammatory and anticoagulant profile of effects makes them suitable substances in the treatment of PHT whose pathogenesis, vasoconstriction, proliferation, vascular modelling and in-situ thromboses play a role. Current tendency is to use other oral drugs as primary and initial treatment. But it is important not to miss the point when prostanoids are required as additional or alternative treatment. Prostanoids are indicated in current treatment algorithms for patients in NYHA class III or IV, especially those in right ventricular failure. Prostanoids can be given by continual intravenous or subcutaneous infusion, by mouth or as inhalants. Inhalant isoprost is practicable and well tolerated and improves the clinical condition and survival prognosis when given to patients with severe PHT. New developments with prostanoids apply largely to combination treatment.

Administration, Inhalation↗

[Current recommendations for the diagnosis and treatment of pulmonary hypertension].

Spiroergometry and Doppler stress echocardiography are recommended in cases of suspected but unproven pulmonary hypertension (PHT). Treatment of the underlying disease is indicated when there is pulmonary hypertension associated with disease of the left heart or the lungs. Surgery is indicated if there if the PHT is caused by chronic thromboembolism. PAH patients in NYHA class III-IV who do not meet response criteria to acute vasodilators, can be treated with prostanoids, endothelin receptor antagonists or phosphodiesterase 5 inhibitors.

3',5'-Cyclic-GMP Phosphodiesterases↗

Sildenafil treatment for portopulmonary hypertension.

Portopulmonary hypertension (POPH) is regarded as a subtype of pulmonary arterial hypertension (PAH); however, established PAH therapies have not been evaluated for this condition. The current authors treated 14 patients (four male, 10 female; mean (range) age 55 (39-75) yrs) with moderate (n = 1) or severe (n = 13) POPH caused by alcoholic liver disease (n = 7), chronic viral hepatitis (n = 3), autoimmune hepatitis (n = 3), and hepatic manifestation of hereditary haemorrhagic teleangiectasia (n = 1) with oral sildenafil. Eight patients were newly started on pulmonary vasoactive treatment, while six patients were already on treatment with inhaled prostanoids (iloprost, n = 5; treprostinil, n = 1). During treatment with sildenafil, mean +/- sd 6-min walk distance increased from 312 +/- 111 m to 397 +/- 99 m after 3 months, and 407 +/- 97 m after 12 months. Mean +/- sd pro-brain natriuretic peptide levels decreased from 582 +/- 315 ng x mL(-1) to 230 +/- 278 ng x mL(-1), and to 189 +/- 274 ng x mL(-1) after 3 and 12 months, respectively. Two patients died after 1 and 2 months from liver failure and cardiac failure, respectively. There was a similar response to sildenafil treatment after 3 and 12 months in patients on monotherapy and those on combination therapy. In conclusion, sildenafil might be effective in monotherapy and in combination therapy with inhaled prostanoids in portopulmonary hypertension, leading to significant improvement by 3 months and sustained response over 12 months.

Administration, Oral↗

Sildenafil improves dynamic vascular function in the brain: studies in patients with pulmonary hypertension.

BACKGROUND: Prostaglandins and nitric oxide play a pivotal role in the regulation of macro- and microcirculatory blood flow distribution. Interference with both mediator systems have been implicated in cerebrovascular dysfunction. Inhaled iloprost (long-acting prostacyclin analogue) and the phosphodiesterase-5 inhibitor sildenafil have recently shown efficacy in the treatment of chronic pulmonary hypertension. We investigated the impact of these agents on cerebral microcirculatory regulation in patients suffering from this disease. METHODS: In 11 patients suffering from severe pulmonary hypertension, a functional transcranial Doppler test utilizing a visual stimulation paradigm was undertaken to measure the evoked flow velocity in the posterior cerebral artery. Measurements were performed in parallel to right heart catheterization and pharmacological testing of the pulmonary vasoreactivity. After assessment of baseline measurements, inhaled iloprost and oral sildenafil were given consecutively for testing of cerebral and pulmonary vascular function. The data gained from the Doppler measurements were compared to data from 22 healthy volunteers. RESULTS: Both substances provoked a significant reduction of pulmonary arterial pressure and vascular resistance, accompanied by minor changes in systemic vascular resistance. In contrast to these superimposable hemodynamic profiles opposite effects were observed regarding cerebral vascular tone: cerebral microvascular reactivity, as assessed by attenuation and time rate parameters, was significantly improved by sildenafil, but slightly worsened by iloprost. CONCLUSIONS: Sildenafil has beneficial effects on cerebral vascular reactivity indicative of an improvement in neurovascular coupling in patients with pulmonary hypertension. These results warrant further investigations of the influence of sildenafil on dynamic vascular function in the brain independent of the underlying disease.

Administration, Inhalation↗

[Therapy of pulmonary arterial hypertension].

New drugs for pulmonary arterial hypertension have shown efficacy in randomized controlled trials. Endothelin receptor antagonists (ERA) and prostanoids are most important for clinical practice. Bosentan represents the first approved orally active therapy for PAH. Besides its hepatotoxicity it is mostly well tolerated. The first approved prostanoid, epoprostenol, is currently first choice only for decompensated right heart failure in PAH. It has to be delivered continuously intravenously and is prone to complications, side effects and very high costs. Alternatively, subcutaneous treprostinil can be applied. It is less risky and expensive but may cause local pain at the infusion site. Inhaled iloprost combines the features of a prostanoid with pulmonary and intrapulmonary selectivity. Alternatively, iloprost is being used as continuous intravenous infusion. The phosphodiesterase-5 inhibitor sildenafil was effective in two randomized controlled trials but has not been approved for PAH therapy.

Antihypertensive Agents↗

Inhaled iloprost is a potent acute pulmonary vasodilator in HIV-related severe pulmonary hypertension.

As antiretroviral therapy has improved life expectancy in human immunodeficiency virus (HIV) infection, the life-limiting complication of HIV-related pulmonary hypertension has come into focus. Inhalation of the stable prostacyclin analogue iloprost is an effective treatment for various forms of precapillary pulmonary hypertension. The main objective of the present study was to evaluate the safety and efficacy of inhaled iloprost in HIV-related pulmonary hypertension. In eight patients with severe pulmonary hypertension related to HIV infection, right heart and femoral artery catheterisation were performed. The acute effect of oxygen, inhaled nitric oxide and aerosolised iloprost was investigated. Four patients underwent long-term treatment with inhaled iloprost. The rank order of pulmonary vasodilatory potency was iloprost>NO>O2, with a maximum reduction (mean +/- SEM) in pulmonary vascular resistance of 30.6 +/- 3.1% (p < 0.001), 5.9 +/- 3.9% and -0.6 +/- 3.9%, respectively. Concomitantly, inhaled iloprost significantly increased the cardiac index and central venous oxygen saturation. Chronic treatment with inhaled iloprost tended to improve the 6 min walking distance and decreased pulmonary vascular resistance in all patients (although not significantly). No serious adverse events and no major interactions with the ongoing antiretroviral therapy were noted. In conclusion, inhaled iloprost is a potent pulmonary vasodilator in human immune deficiency virus-related pulmonary hypertension. Future studies are warranted to confirm the encouraging long-term beneficial results observed in the present limited number of patients.

Administration, Inhalation↗

Molecular and functional analysis identifies ALK-1 as the predominant cause of pulmonary hypertension related to hereditary haemorrhagic telangiectasia.

BACKGROUND: Mutations of the transforming growth factor beta (TGFbeta) receptor components ENDOGLIN and ALK-1 cause the autosomal dominant vascular disorder hereditary haemorrhagic telangiectasia (HHT). Heterozygous mutations of the type II receptor BMPR2 underlie familial primary pulmonary hypertension. OBJECTIVE: To investigate kindreds presenting with both pulmonary hypertension and HHT. METHODS: Probands and families were identified by specialist pulmonary hypertension centres in five countries. DNA sequence analysis of ALK-1, ENDOGLIN, and BMPR2 was undertaken. Cellular localisation was investigated by heterologous overexpression of mutant constructs in both BAEC and HeLa cells. The impact of a novel sequence variant was assessed through comparative analysis and computer modelling. RESULTS: Molecular analysis of 11 probands identified eight missense mutations of ALK-1, one of which was observed in two families. Mutations were located within exons 5 to 10 of the ALK-1 gene. The majority of ALK-1 mutant constructs appeared to be retained within the cell cytoplasm, in the endoplasmic reticulum. A novel GS domain mutation, when overexpressed, reached the cell surface but is predicted to disrupt conformational changes owing to loss of a critical hydrogen bond. Two novel missense mutations were identified in ENDOGLIN. CONCLUSIONS: The association of pulmonary arterial hypertension and HHT identifies an important disease complication and appears most common among subjects with defects in ALK-1 receptor signalling. Future studies should focus on detailed molecular analysis of the common cellular pathways disrupted by mutations of ALK-1 and BMPR2 that cause inherited pulmonary vascular disease.

Activin Receptors, Type I↗

Zardaverine and aerosolised iloprost in a model of acute respiratory failure.

In this study, the impact of aerosolised prostacyclin (PGI2) and iloprost in the absence or presence of subthreshold intravascular doses of the dual-selective phosphodiesterase-3/4 inhibitor zardaverine was investigated in an experimental model of acute respiratory failure. In perfused rabbit lungs, continuous infusion of the thromboxane-A2-mimetic U46619 provoked pulmonary hypertension, accompanied by progressive lung oedema formation and severe ventilation-perfusion mismatch with predominance of shunt flow (increasing from approximately 2 to 58%, as assessed by the multiple inert gas elimination technique). Aerosolisation of PGI2 (in total 1.05 microg x kg(-1) for 15 min caused a decrease in pulmonary artery pressure (Ppa) and a limitation of maximum shunt flow to approximately 37%. When nebulised PGI2 was combined with subthreshold intravascular zardaverine, which did not affect pulmonary haemodynamics per se, the duration of the PGI2 effect was increased. Aerosolisation of 3 microg x kg(-1) PGI2 resulted in a transient decrease in Ppa and a reduction in shunt flow. In the presence of subthreshold zardaverine, the effects of this PGI2 dose were only marginally increased. Aerosolisation of iloprost (in total 0.7 microg x kg(-1)) for 15 min caused a more sustained decrease in Ppa, some enhanced reduction of oedema formation as compared with PGI2 and a decrease in shunt flow to approximately 32%. Most impressively, when combined with subthreshold zardaverine, iloprost suppressed oedema formation to <15% and shunt flow to approximately 8%. In conclusion, combined use of aerosolised iloprost and subthreshold systemic phosphodiesterase-3/4 inhibitor may result in selective intrapulmonary vasodilation, a reduction in oedema formation and an improvement in ventilation-perfusion matching in acute respiratory failure.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗

[Sildenafil for treatment of severe pulmonary hypertension and commencing right-heart failure].

Pulmonary hypertension (PHT) is mainly explained by four underlying pathophysiological phenomena: 1. Vasoconstriction, 2. reduction of pulmonary vascular bed, 3. reduction in vessel elasticity, and 4. obliteration of the vessel lumen by thrombotic material and subsequent cellular alterations of the vessel wall (vascular remodeling). Chronic right heart load is thus a consequence of increased pulmonary pressure and vascular resistance. Main targets of advanced therapeutic strategies are therefore first: resolution of chronically increased vascular tone by smooth muscle cell relaxation (vasodilators), second: reversal of vascular remodeling and third: prevention from pulmonary embolization and/or in-situ thrombosis (chronic anticoagulation). Long term administration of high dose calcium channel blockers (though operative only in a minority of 10 - 15 % of all patients), prostanoids (eg. prostacyclin, iloprost), and the recently approved unselective oral endothelin antagonist bosentan are regarded as established medical therapies for treatment of chronic PHT. However, applicability of these substances can be limited by potentially serious adverse events and/or necessity for elaborate parenteral application. Recent data are indicative for a strong pulmonary vasodilative potency of the selective phosphodiesterase-5 (PDE5) inhibitor sildenafil. Smaller clinical studies and numerous case reports underline the good tolerability of this orally applied substance in various form of PHT. Based on these encouraging results, the simple availability, and the low costs (in comparison to "established therapies") of the drug, sildenafil is currently widely used in an "off-label" indication for treatment of PHT. Controlled randomized studies have to confirm the current findings, before general recommendations regarding the use of sildenafil for treatment of PHT can be made.

Clinical Trials as Topic↗

Peripheral airway obstruction in primary pulmonary hypertension.

BACKGROUND: As there is controversy about changes in lung function in primary pulmonary hypertension (PPH), lung mechanics were assessed with a focus on expiratory airflow in relation to pulmonary haemodynamics. METHODS: A cross sectional study was performed in 64 controls and 171 patients with PPH (117 women) of mean (SD) age 45 (13) years, pulmonary artery pressure (PAPmean) 57 (15) mm Hg, and pulmonary vascular resistance 1371 (644) dyne.s/cm(5). RESULTS: Mean (SD) total lung capacity was similar in patients with PPH and controls (98 (12)% predicted v 102 (17)% predicted, mean difference -4 (95% confidence interval (CI) -7.89 to -0.11); residual volume (RV) was increased (118 (24)% predicted v 109 (27)% predicted, mean difference 9 (95% CI 1.86 to 16.14); and vital capacity (VC) was decreased (91 (16)% predicted v 102 (10)% predicted, mean difference -11 (95% CI 15.19 to -6.80). RV/TLC was increased (117 (27)% predicted v 97 (29)% predicted, mean difference 20 (95% CI 12.3 to 27.8)) and correlated with PAPmean (r=0.31, p<0.001). In patients with PAPmean above the median of 56 mm Hg, RV/TLC was further increased (125 (32)% predicted v 111 (22)% predicted, mean difference -14 (95% CI -22.2 to -5.8)). Expiratory flow-volume curves were reduced and curvilinear in patients with PPH. CONCLUSIONS: Peripheral airway obstruction is common in PPH and is more pronounced in severe disease. This may contribute to symptoms. Reversibility of bronchodilation and relation to exercise capacity need further evaluation.

Airway Obstruction↗

Nocturnal periodic breathing in primary pulmonary hypertension.

Cheyne-Stokes respiration is frequently observed in congestive heart failure. Among other factors, prolongation of circulation time, hypocapnia and hypoxia are thought to underlie this sleep-related breathing disorder. Primary pulmonary hypertension (PPH) is also characterized by reduced cardiac output and blood gas alterations. Therefore, the aim of the present study was to determine whether a nocturnal periodic breathing (PB) occurs in PPH. A total of 20 consecutive patients with PPH who had been admitted for pharmacological investigation of pulmonary vasoreactivity were investigated by lung function testing, right heart catheterization and full-night attended polysomnography. PB was detected in six patients (30%) (mean +/- SEM: apnoea/hypopnoea index 37 +/- 5 h(-1); arterial oxygen saturation was <90% during 56 +/- 6.5% of total sleep time). The patients with PB had more severe haemodynamic impairment than those without. They also had a more marked reduction in the pulmonary diffusion capacity and greater arterial hypoxia. PB was markedly improved or even eradicated by nasal oxygen during the night. Periodic breathing occurs in patients with advanced primary pulmonary hypertension and can be reversed by nocturnal nasal oxygen. The clinical and prognostic significance of periodic breathing in primary pulmonary hypertension needs to be determined by further studies.

Cardiac Catheterization↗

Lung cGMP release subsequent to NO inhalation in pulmonary hypertension: responders versus nonresponders.

Inhalation of nitric oxide (NO) is widely employed for the assessment of pulmonary vasoresponsiveness in pulmonary hypertension (PH). However, the reasons for the huge differences in vascular reactivity to NO between patients are unknown, and the role of NO-induced cyclic guanosine monophosphate (cGMP) is unclear. Twenty patients with severe precapillary PH were investigated. Thirty-six Swan-Ganz catheter investigations were performed and the study subjects were tested for responses to NO inhalation. This included an assessment of pulmonary and systemic arterial plasma cGMP and atrial natriuretic peptide (ANP) levels. A significant NO response (pulmonary vascular resistance (PVR) decrease >20%) was noted in nine of 20 patients (45%) during the first catheterization. A highly significant correlation between baseline plasma cGMP and ANP levels with PVR was observed (r=0.62 and r=0.66, respectively; p<0.0001). In response to NO, systemic and mixed venous cGMP levels increased from 13.9 +/- 1.28 nM and 12.75 +/- 0.99 nM to 79.23 +/- 4.99 nM and 55.25 +/- 4.41 nM (p<0.001), respectively, accompanied by the appearance of a marked transpulmonary cGMP gradient. Although in the responder group ANP levels were significantly reduced after NO inhalation, no significant correlation was observed to the extent of PVR reduction. The magnitude of the NO-elicited cGMP response did not discriminate between haemodynamic responders and nonresponders. This study concludes that plasma cyclic guanosine monophosphate levels are significantly correlated with the severity of disease in pulmonary arterial hypertension. Nitric oxide inhalation provokes a prompt increase in cyclic guanosine monophosphate secretion, but the magnitude of this release is not linked with a decrease in pulmonary vascular resistance.

Administration, Inhalation↗