Prostanoids In Patients Research Articles

Prostanoids in patients with diabetes and chronic limb-threatening ischemia: a meta-analysis of randomized clinical trials for the development of the Italian guidelines for the treatment of diabetic foot syndrome.

Prostanoids in patients with diabetes and chronic limb-threatening ischemia: a meta-analysis of randomized clinical trials for the development of the Italian guidelines for the treatment of diabetic foot syndrome.

Effect of statin treatment on metabolites, lipids and prostanoids in patients with Statin Associated Muscle Symptoms (SAMS).

Between 5-10% of patients discontinue statin therapy due to statin-associated adverse reactions, primarily statin associated muscle symptoms (SAMS). The absence of a clear clinical phenotype or of biomarkers poses a challenge for diagnosis and management of SAMS. Similarly, our incomplete understanding of the pathogenesis of SAMS hinders the identification of treatments for SAMS. Metabolomics, the profiling of metabolites in biofluids, cells and tissues is an important tool for biomarker discovery and provides important insight into the origins of symptomatology. In order to better understand the pathophysiology of this common disorder and to identify biomarkers, we undertook comprehensive metabolomic and lipidomic profiling of plasma samples from patients with SAMS who were undergoing statin rechallenge as part of their clinical care. We report our findings in 67 patients, 28 with SAMS (cases) and 39 statin-tolerant controls. SAMS patients were studied during statin rechallenge and statin tolerant controls were studied while on statin. Plasma samples were analyzed using untargeted LC-MS metabolomics and lipidomics to detect differences between cases and controls. Differences in lipid species in plasma were observed between cases and controls. These included higher levels of linoleic acid containing phospholipids and lower ether lipids and sphingolipids. Reduced levels of acylcarnitines and altered amino acid profile (tryptophan, tyrosine, proline, arginine, and taurine) were observed in cases relative to controls. Pathway analysis identified significant increase of urea cycle metabolites and arginine and proline metabolites among cases along with downregulation of pathways mediating oxidation of branched chain fatty acids, carnitine synthesis, and transfer of acetyl groups into mitochondria. The plasma metabolome of patients with SAMS exhibited reduced content of long chain fatty acids and increased levels of linoleic acid (18:2) in phospholipids, altered energy production pathways (β-oxidation, citric acid cycle and urea cycles) as well as reduced levels of carnitine, an essential mediator of mitochondrial energy production. Our findings support the hypothesis that alterations in pro-inflammatory lipids (arachidonic acid pathway) and impaired mitochondrial energy metabolism underlie the muscle symptoms of patients with statin associated muscle symptoms (SAMS).

Efficacy comparison of prostacyclin analogue and prostacyclin receptor agonist as third line treatment for pulmonary arterial hypertension

Abstract Background Pulmonary arterial hypertension (PAH) is a progressive disease characterized by small pulmonary arteries remodeling that leads to increased pulmonary vascular resistance, dyspnea, fatigue, right heart failure and ultimately death. Prostacyclin analogue drugs, such as epoprostenol or treprostinil, have a vasodilator, antiproliferative and immunomodulatory effect, representing established therapies for cases of severe PAH. Both these drugs improve exercise capacity, functional class and hemodynamic parameters, while epoprostenol also improves survival among patients with PAH. Despite these therapeutic benefits, these treatments need parenteral administration. Recently, the approval of selexipag, an oral selective prostacyclin receptor agonist, may represent a possible alternative option in some PAH patients. Methods Patients with PAH treated as third line therapy with epoprostenol, treprostinil or selexipag, on top of inhibitor of type 5 phosphodiesterases and endothelin-1 receptor antagonists, referred to our center from February 1995 to December 2021 were retrospectively included. All patients noninvasive [6 minutes walking distance (6MWD)] and invasive [mean pulmonary arterial pressure (mPAP), pulmonary vascular resistance (PVR), cardiac index (CI), right atrial pressure (RAP) and mixed venous oxygen saturation (SvO2)] parameters were first collected at the baseline right heart catheterization (prior to the beginning of prostacyclin treatment) and then 3-4 months after the beginning of third line therapy. The absolute improvements in these parameters were compared with Dunn’s test. Data are expressed as median (interquartile range). Results 153 PAH patients treated as third line therapy with epoprostenol, treprostenil and selexipag were included (44, 73, 36 patients respectively). At 3 to 4 months after the beginning of the third line therapy, absolute improvements in the different parameters are shown in Figure 1. Conclusions In our study population, epoprostenol, treprostenil and selexipag improve both exercise capacity and haemodynamic parameters in PAH patients when used as third line therapy, with the highest efficacy in the first group and, possibly, the lowest efficacy in the latter. These results confirm the beneficial role of these drugs in PAH patients and may suggest a possible favorable role for selexipag in the management of PAH patients with a less severe disease reserving a more invasive treatment strategy with parenteral prostanoids in patients with a higher risk disease.Figure 1

109 EFFICACY COMPARISON OF PROSTACYCLIN ANALOGUE AND PROSTACYCLIN RECEPTOR AGONIST AS THIRD LINE TREATMENT FOR PULMONARY ARTERIAL HYPERTENSION

Abstract Background Pulmonary arterial hypertension (PAH) is a progressive disease characterized by small pulmonary arteries remodeling that leads to increased pulmonary vascular resistance, dyspnea, fatigue, right heart failure and ultimately death. Prostacyclin analogue drugs, such as epoprostenol or treprostinil, have a vasodilator, antiproliferative and immunomodulatory effect, representing established therapies for cases of severe PAH. Both these drugs improve exercise capacity, functional class and hemodynamic parameters, while epoprostenol also improves survival among patients with PAH. Despite these therapeutic benefits, these treatments need parenteral administration. Recently, the approval of selexipag, an oral selective prostacyclin receptor agonist, may represent a possible alternative option in some PAH patients. Methods patients with PAH treated as third line therapy with epoprostenol, treprostinil or selexipag, on top of inhibitor of type 5 phosphodiesterases and endothelin-1 receptor antagonists, referred to our center from February 1995 to December 2021 were retrospectively included. All patients noninvasive [6 minutes walking distance (6MWD)] and invasive [mean pulmonary arterial pressure (mPAP), pulmonary vascular resistance (PVR), cardiac index (CI), right atrial pressure (RAP) and mixed venous oxygen saturation (SvO2)] parameters were first collected at the baseline right heart catheterization (prior to the beginning of prostacyclin treatment) and then 3-4 months after the beginning of third line therapy. The absolute improvements in these parameters were compared with Dunn's test. Data are expressed as median (interquartile range). Results 153 PAH patients treated as third line therapy with epoprostenol, treprostenil and selexipag were included (44, 73, 36 patients respectively). At 3 to 4 months after the beginning of the third line therapy, improvements in the 6MWD were: 65 (25 - 132) m with epoprostenol, 16 (-8 - 63) m with treprostenil and 12 (-10 - 57) m with selexipag (p = 0.044). Absolute RAP reduction was -1 (-4–2.5) mmHg with epoprostenol, -1 (-3 - 2) mmHg with treprostenil and 0 (-4 - 2) mmHg with selexipag (p = 0.953). Absolute PAPm reduction was -5 (-9 - -1) mmHg with epoprostenol, -5 (-11 - -1) mmHg with treprostenil and -6.5 (-14 - 0) mmHg with selexipag (p = 0.670). Absolute CI improvement was 0.9 (0.4–1.1) l/min/m2 with epoprostenol, 0.5 (0.2–0.8) l/min/m2 with treprostenil and 0.3 (0.1 - 1) l/min/m2 with selexipag (p = 0.022). Absolute PVR improvement was -4.5 (-7.6 - -2) WU with epoprostenol, -3.2 (-4.9 - -1.7) WU with treprostenil and -2 (-4.4–0.9) WU with selexipag (p = 0.021). Absolute SvO2 increase was 4.8 (1.7–13.2) % with epoprostenol, 2.6 (-2.2–6.2) % with treprostenil and 2.3 (-2.4–7.5) % with selexipag (p = 0.036). For all three-way significant comparisons, the only pairwise comparisons with a p-value <0.05 were between epoprostenol vs the other two drugs. Conclusions in our study population, epoprostenol, treprostenil and selexipag improve both exercise capacity and haemodynamic parameters in PAH patients when used as third line therapy, with the highest efficacy in the first group and, possibly, the lowest efficacy in the latter. These results confirm the beneficial role of these drugs in PAH patients and may suggest a possible favorable role for selexipag in the management of PAH patients with a less severe disease reserving a more invasive treatment strategy with parenteral prostanoids in patients with a higher risk disease.

P4160Safety and efficacy of triple combination therapy with parenteral prostanoids in patients with Eisenmenger physiology

Abstract Aim While combination therapy is currently strongly advocated for idiopathic pulmonary arterial hypertension (PAH) patients, evidence to support its use in patients with PAH related to congenital heart disease (CHD), especially patients with Eisenmenger syndrome, is lacking. We evaluated the efficacy and safety of sequential triple combination therapy with parenteral prostanoids after failure of double oral therapy in patients with PAH-CHD and Eisenmenger physiology. Methods This is an international, multicentre, retrospective cohort study conducted in adult patients with Eisenmenger physiology on double oral PAH therapy in whom intravenous or subcutaneous prostanoid treatment was added due to clinical deterioration or failure to reach the treatment goals. Clinical status, 6-minute walk test distance (6MWD), biomarkers and haemodynamics were assessed at baseline and during the follow-up. Results A total 28 patients with Eisenmenger syndrome (6 [21%] male, age 37.6±14.3 years) were included. A post-tricuspid shunt was present in 16 (57%), 86% of whom had a ventricular septal defect. The majority (89%) were treated with subcutaneous treprostinil. At 27±14 months follow-up, WHO functional class improved in 18 (64%), remained unchanged in 8 (29%), and deteriorated in 2 (7%) patients. There was also an increase in 6MWD (mean 339±145 versus 233±140m, p=0.0001, fig 1A) and a reduction in NT-proBNP levels (median 1125 [123–5882] versus 3087 [234–7428] pg/mL, p<0.0001, fig 1B). On follow-up cardiac catheterization, an improvement in right atrial pressure (8±2 versus 11±5 mmHg, p=0.01), mean pulmonary artery pressure (68±12 versus 72±17 mmHg, p=0.005), cardiac index (2.3±0.3 versus 2.0±0.5 l/min/m2, p=0.005, fig 1C), and pulmonary vascular resistance (17±7 versus 21±10, p=0.008, fig 1D), was observed compared to baseline. No patients discontinued treatment. Five (18%) patients died during follow up. Figure 1 Conclusions Triple combination therapy with subcutaneous treprostinil or endovenous epoprostenol in patients with Eisenmenger syndrome is safe and well tolerated at 2 years follow-up, resulting in a significant improvement in clinical status, exercise tolerance and haemodynamics.

Prostanoids for critical limb ischaemia.

Peripheral arterial occlusive disease (PAOD) is a common cause of morbidity and mortality due to cardiovascular disease in the general population. Although numerous treatments have been adopted for patients at different disease stages, no option other than amputation is available for patients presenting with critical limb ischaemia (CLI) unsuitable for rescue or reconstructive intervention. In this regard, prostanoids have been proposed as a therapeutic alternative, with the aim of increasing blood supply to the limb with occluded arteries through their vasodilatory, antithrombotic, and anti-inflammatory effects. This is an update of a review first published in 2010. To determine the effectiveness and safety of prostanoids in patients with CLI unsuitable for rescue or reconstructive intervention. For this update, the Cochrane Vascular Information Specialist searched the Specialised Register (January 2017) and the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 1). In addition, we searched trials registries (January 2017) and contacted pharmaceutical manufacturers, in our efforts to identify unpublished data and ongoing trials. Randomised controlled trials describing the efficacy and safety of prostanoids compared with placebo or other pharmacological control treatments for patients presenting with CLI without chance of rescue or reconstructive intervention. Two review authors independently selected trials, assessed trials for eligibility and methodological quality, and extracted data. We resolved disagreements by consensus or by consultation with a third review author. For this update, 15 additional studies fulfilled selection criteria. We included in this review 33 randomised controlled trials with 4477 participants; 21 compared different prostanoids versus placebo, seven compared prostanoids versus other agents, and five conducted head-to-head comparisons using two different prostanoids.We found low-quality evidence that suggests no clear difference in the incidence of cardiovascular mortality between patients receiving prostanoids and those given placebo (risk ratio (RR) 0.81, 95% confidence interval (CI) 0.41 to 1.58). We found high-quality evidence showing that prostanoids have no effect on the incidence of total amputations when compared with placebo (RR 0.97, 95% CI 0.86 to 1.09). Adverse events were more frequent with prostanoids than with placebo (RR 2.11, 95% CI 1.79 to 2.50; moderate-quality evidence). The most commonly reported adverse events were headache, nausea, vomiting, diarrhoea, flushing, and hypotension. We found moderate-quality evidence showing that prostanoids reduced rest-pain (RR 1.30, 95% CI 1.06 to 1.59) and promoted ulcer healing (RR 1.24, 95% CI 1.04 to 1.48) when compared with placebo, although these small beneficial effects were diluted when we performed a sensitivity analysis that excluded studies at high risk of bias. Additionally, we found evidence of low to very low quality suggesting the effects of prostanoids versus other active agents or versus other prostanoids because studies conducting these comparisons were few and we judged them to be at high risk of bias. None of the included studies assessed quality of life. We found high-quality evidence showing that prostanoids have no effect on the incidence of total amputations when compared against placebo. Moderate-quality evidence showed small beneficial effects of prostanoids for rest-pain relief and ulcer healing when compared with placebo. Additionally, moderate-quality evidence showed a greater incidence of adverse effects with the use of prostanoids, and low-quality evidence suggests that prostanoids have no effect on cardiovascular mortality when compared with placebo. None of the included studies reported quality of life measurements. The balance between benefits and harms associated with use of prostanoids in patients with critical limb ischaemia with no chance of reconstructive intervention is uncertain; therefore careful assessment of therapeutic alternatives should be considered. Main reasons for downgrading the quality of evidence were high risk of attrition bias and imprecision of effect estimates.

Prostanoids in patients with peripheral arterial disease: A meta-analysis of placebo-controlled randomized clinical trials

AimsProstanoids are indicated in the treatment of peripheral arterial disease (PAD). Available trials suggest that these compounds could reduce the symptoms of intermittent claudication, even though the quality of studies is poor. The present meta-analysis is aimed at verifying the effects of prostanoids on amputation rate and ulcer healing in patients with lower limb PAD. Materials and methodsThe review protocol was published on http://www.crd.york.ac.uk/prospero (CRD42015020258). A comprehensive search for published and unpublished trials comparing iloprost, alprostadil, prostaglandin-E1, epoprostenol, or taprostene with placebo/no therapy on amputation rate in patients with PAD and ulcer healing rate in patients with concomitant foot ulcers. Mantel–Haenzel odds ratio (MH-OR) was calculated with random effect models for the chosen endpoints. ResultsA total of 18 trials, enrolling 3,077 and 2,763 patients in the prostanoid and comparator groups, respectively were included in the analysis. Only 11 and 10 of those trials reported data on total and major amputations, respectively. Prostanoids were associated with a significantly lower risk of major (MH-OR [95% confidence interval] was 0.77 [0.63; 0.93], p=0.007), but not total, amputations. Healing rate (available only in 7 trials) was not significantly augmented by prostanoid treatment. ConclusionsAvailable data are not sufficient to support an extensive use of prostanoids in patients with critical limb ischemia, as an adjunct to revascularization or as an alternative to major amputation in cases which cannot undergo revascularization.

Prostanoids for intermittent claudication

Peripheral arterial disease (PAD) is a common cause of morbidity in the general population. While numerous studies have established the efficacy of prostanoids in PAD stages III and IV, the question of the role of prostanoids as an alternative or additive treatment in patients suffering from intermittent claudication (PAD II) has not yet been clearly answered. This is an update of a Cochrane Review first published in 2004. To determine the effects of prostanoids in patients with intermittent claudication (IC) Fontaine stage II. For this update, the Cochrane Peripheral Vascular Diseases Group Trials Search Co-ordinator (TSC) searched the Specialised Register (last searched January 2013) and CENTRAL (2012, Issue 12). Clinical trials databases were searched for details of ongoing or unpublished studies. In addition, reference lists of relevant articles were checked. Randomised clinical trials of prostanoids versus placebo or alternative ('control') treatment in people with intermittent claudication were considered for inclusion. Two authors independently assessed trial quality and extracted data. Primary outcomes included pain-free walking distance (PFWD) and maximum walking distance (MWD), presented as mean change in walking distance during the course of the trial (% improvement) and as final walking distance (that is walking distance, in metres, after treatment) for the prostanoid and control groups. Eighteen trials with a total of 2773 patients were included (16 in the original review and a further two in this update). As the majority of trials did not report standard deviations for the primary PFWD and MWD outcomes, it was often not possible to test for the statistical significance of any improvements in walking distance between groups. The quality of individual trials was variable and usually unclear due to insufficient reporting information. Comparison between trials was hampered by the use of different treadmill testing protocols, including different walking speeds and gradients. Such limitations in the data and the trial heterogeneity meant it was not possible to meaningfully pool results by meta-analysis.Four trials compared prostaglandin E1 (PGE1) with placebo; individual trials showed significant increases in walking distances with administration of PGE1 and in several trials the walking capacity remained increased after termination of treatment. Compared with pentoxifylline, PGE1 was associated with a higher final PFWD and MWD but these results were based on final walking distances rather than changes in walking distance from baseline. When PGE1 was compared with other treatments including laevadosin, naftidrofuryl and L-arginine, improvements in walking distances over time were observed for both PGE1 and the alternative treatment, but it was not possible from the data available to analyse statistically whether or not one treatment was more effective than the other.Six studies compared various preparations of prostacyclins (PGI2) with placebo. In one study using three different dosages of iloprost, PFWD and MWD appeared to increase in a dose-dependent manner; iloprost was associated with headache, pain, nausea and diarrhoea, leading to a higher rate of treatment withdrawal. Of three studies using beraprost sodium, one showed an improvement in PFWD and MWD compared with placebo while two showed no significant benefit. Beraprost sodium was associated with an increased incidence of drug-related adverse events. Of two studies on taprostene, the results of one in particular must be interpreted with caution due to an imbalance in walking capacity at baseline.Comprehensive, high quality data on outcomes such as quality of life, ankle brachial index, venous occlusion plethysmography and haemorrheological parameters were lacking. Whilst results from some individual studies suggested a beneficial effect of PGE1, the quality of these studies and of the overall evidence available is insufficient to determine whether or not patients with intermittent claudication derive clinically meaningful benefit from the administration of prostanoids. Further well-conducted randomised, double blinded trials with a sufficient number of participants to provide statistical power are required to answer this question.

Efficacy of prostanoids in patients with critical leg ischemia

Prostanoids (alprostadil and iloprost) are used for the treatment of patients with critical limb ischemia in whom revascularization procedure is inadequate or proved to be unsuccessful. According to a Cochrane analysis (CD006544) prostanoids differ in their effects on rest-pain relief and ulcer healing. Objectives: To study the efficacy and safety of prostanoids for critical limb ischemia. Methods: Systematic literature search and meta-analysis (mixed treatment comparison) was performed. Results: Seven randomized controlled trials including 964 patients were analyzed. Compared to placebo, both alprostadil (OR: 3.2 95% CI: 1.7–5.5 and OR: 1.8 95% CI: 0.6–4.3) and iloprost (OR: 2.7 95% CI: 1.7–4.2 and OR: 2.5 95% CI: 1.0–5.4) were more efficacious with regard to rest-pain relief and ulcer healing and the difference between the two prostanoids was not significant (OR: 1.2 95% CI: 0.7–1.9 and OR: 0.74 95% CI: 0.3–1.5). Adverse events occurred significantly more often with both drugs compared to placebo, however, they were less frequent with alprostadil than with iloprost (OR 0.2 95% CI: 0.1–0.3). Conclusions: Prostanoids have favorable effect on rest-pain relief and ulcer healing in critical limb ischemia, without statistically significant difference between the two available drugs. The Cochrane study (CD006544) reported mistaken results due to defaults in the analysis. Orv. Hetil., 2011, 152, 2047–2055.

Prostanoids for critical limb ischaemia

Peripheral arterial occlusive disease (PAOD) is a common cause of morbidity and mortality due to cardiovascular diseases in the general population. While numerous treatments have been adopted for different disease stages, there is no option other than amputation for patients presenting with critical limb ischaemia (CLI), unsuitable for rescue or reconstructive intervention. To determine the effectiveness and safety of prostanoids in patients presenting with CLI. The Cochrane Peripheral Vascular Diseases Group searched their trials register (last searched October 2009) and the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library (last searched 2009, Issue 4) for publications describing randomised controlled trials (RCTs) of prostanoids for CLI. We ran additional searches in MEDLINE, EMBASE, LILACS, and SciSearch, and we also contacted pharmaceutical companies and experts, in order to identify unpublished data and trials still underway. Randomised controlled trials describing efficacy and safety of prostanoids compared with placebo or other pharmacological control treatments, in patients presenting with CLI, without chance of rescue or reconstructive intervention. Two authors independently selected trials, assessed trials for eligibility and methodological quality, and extracted data. Disagreements were resolved by consensus or by the third author. We retrieved 532 citations which after the first screening resulted in 111 potential studies. Finally, after exclusion of studies of poor quality and a lack of sufficient information, 20 trials were included in the review.Prostanoids seem to have efficacy regarding rest-pain relief (risk ratio (RR) 1.32, 95% confidence interval (CI) 1.10 to 1.57; P = 0.003), and ulcer healing (RR 1.54, 95% CI 1.22 to 1.96). Iloprost also shows favourable results regarding major amputations (RR 0.69, 95% CI 0.52 to 0.93). The more frequently reported adverse events when using prostanoids were headache, facial flushing, nausea, vomiting and diarrhoea. Despite some positive results regarding rest-pain relief, ulcer healing and amputations, there is no conclusive evidence based on this meta-analysis of the long-term effectiveness and safety of different prostanoids in patients with CLI. Further well-conducted, high quality randomised double-blinded trials should be performed.

Treprostinil potentiates the positive inotropic effect of catecholamines in adult rat ventricular cardiomyocytes

Prostanoids have been shown to improve exercise tolerance, hemodynamics and quality of life in patients with pulmonary arterial hypertension (PAH). We investigated whether treprostinil exerts direct contractile effects on cardiomyocytes that may explain partly the beneficial effects of these drugs. Ventricular cardiomyocytes from adult rats were paced at a constant frequency of 0.5 to 2.0 Hz and cell shortening was monitored via a cell edge detection system. Twitch amplitudes, expressed as percent cell shortening of the diastolic cell length, and maximal contraction velocity, relaxation velocity, time to peak of contraction and time to reach 50% of relaxation were analyzed. Treprostinil (0.15 - 15 ng ml(-1)) slightly increased contractile dynamics of cardiomyocytes at clinically relevant concentrations. However, the drug significantly improved cell shortening of cardiomyocytes in the presence of isoprenaline, a beta-adrenoceptor agonist. Treprostinil exerted this effect at all beating frequencies under investigation. Treprostinil mimicked this potentiating effect in a Langendorff preparation as well. The potentiating effect of treprostinil on isoprenaline-dependent cell shortening was no longer seen after phosphodiesterase inhibition. Long-term cultivation of cardiomyocytes with treprostinil did not modify load free cell shortening of these cells, but reduces the duration of contraction. We conclude that the clinically used prostanoid treprostinil potentiates the positive inotropic effects of catecholamines in adult ventricular cardiomyocytes. This newly described effect may contribute to the beneficial clinical effects of prostanoids in patients with PAH.

Prostanoids for intermittent claudication.

Peripheral arterial occlusive disease (PAOD) is a common cause of morbidity in the general population. While numerous studies have established the efficacy of prostanoids in PAOD stages III and IV the question of the role of prostanoids as an alternative or additive treatment in patients suffering from claudicatio intermittens (PAOD II) has not yet been clearly answered. The aim of this review was to evaluate effects of prostanoids in patients with intermittent claudication. Computerised searches of the Cochrane Peripheral Vascular Diseases Specialised Register (last searched April 2003), The Cochrane Central Register of Controlled Trials (CENTRAL) (last searched Issue 1, 2003), MEDLINE and EMBASE were undertaken. In addition relevant journals were hand-searched. Randomized clinical trials describing the effects of prostanoids in the treatment of patients suffering from intermittent claudication have been considered for inclusion. All reviewers assessed the quality of studies and extracted data unblinded. Statistical analysis including tests for heterogeneity and overall effect were performed by using MetaView of Review Manager 4.2. All numeric values are expressed as mean +/- Standard deviation (SD). Eighteen studies were included for analysis. A significant heterogeneity between the included studies was detected in most of the subgroup analysis. Five studies compared the effects of prostaglandin E1 (PGE1) versus placebo, and reported in their individual results significant increases in walking distances after the administration of PGE1. The attained increase in walking distances appears to be not merely a short-term effect because several studies reported that walking capacity remained increased even after termination of treatment. On the other hand, oral or intravenous prostacyclin did not increase the walking distances significantly. At least one adverse reaction was reported from 23.6% of the patients treated with prostacyclin (PGI2), and its analogues and from 13.7% of the patients treated with PGE1. Because of the heterogeneity between most of the included studies, we did not pool relevant parts of the data by meta-analysis. Based on the individual results of the published literature, patients with intermittent claudication seem to benefit from administration (intravenous or intra-arterial) of PGE1 by a significant improvement of their walking capacity. Further well-conducted randomized, double blinded trials, with a sufficient number of patients to provide statistical powerful information, should be performed to confirm the results of this review.

Plasma thromboxane and prostacyclin are linearly related and increased in patients presenting with acute myocardial infarction

The role of prostanoids in patients with ischemic heart disease including acute myocardial infarction (AMI) has been recognized. However, there is very limited knowledge of the baseline TXB 2and 6-keto-PGF 1aplasma levels in patients with AMI before therapy has been administered. We compared plasma levels of TXB 2and 6-keto-PGF 1aby enzyme immunoassay in 18 AMI patients before thrombolysis, with those of 13 healthy controls. Plasma levels of TXB 2(319.78±16.50 pg/ml) and 6-keto-PGF 1a(536.72±56.71 pg/ml) were heterogeneous, but significantly higher in the AMI patients than in controls (175.92±17.29 pg/ml and 192.08±26.11 pg/ml, respectively). In some patients, long-term aspirin therapy mildly inhibits baseline prostanoid levels, however, limited data prevents us from further speculations on this issue. Although, the contributions by prostanoids to the pathogenesis of AMI have been well proposed, their plasma concentrations are not uniformly elevated, and it is still unclear whether the resultant changes are indicative of clinically meaningful effects.

An imbalance in plasma prostanoids in patients with Raynaud's phenomenon and pulmonary vasospasm.

Raynaud's phenomenon has been suggested as a predisposing factor for pulmonary vasospasm which may lead to pulmonary hypertension, but the occurrence of cold stimulus-induced pulmonary vasospasm has been inconsistent. Such inconsistent pulmonary vascular responses may be caused by differences in the production of endogenous vasodilators and vasoconstrictors among patients. Fourteen patients with Raynaud's phenomenon associated with mixed connective tissue disease (n=10) or systemic sclerosis (n=4) participated in the study. Right heart catheterization was performed before and after a cold pressor test, immersing a hand in cold water (15 degrees C) for 5 min. Plasma levels of 6-keto prostaglandin (PG)F1alpha, thromboxane (TX)B2 and endothelin (ET)-1 in the mixed venous blood were measured. Mean pulmonary artery pressure increased after the cold pressor test in five of 14 patients, and the patients were divided into those with pulmonary vasospasm (responders) and those without vasospasm (nonresponders). After the cold pressor test, levels of 6-keto PGF1alpha increased significantly in nonresponders (p<0.01) and decreased significantly in responders (p<0.05). The ratios of 6-keto PGF1alpha to TXB2 significantly increased in nonresponders (p<0.01) but not in responders and the difference between responders and nonresponders after the cold pressor test was also statistically significant (p<0.05). No significant change in plasma ET-1 levels occurred in either responders or nonresponders. The results suggest that an impaired production of prostaglandin I2 and an imbalance between prostaglandin I2 and thromboxane A2 are associated with the occurrence of pulmonary vasospasm induced by Raynaud's phenomenon.

Reversible Acute Decrease in Renal Function by NSAIDs in Cirrhosis

The effects of sulindac were compared with those of ibuprofen or naproxen on creatinine clearance and urinary prostanoids in patients with severe alcoholic cirrhosis. Sulindac caused acute declines in all renal parameters in four of five patients. The effect occurred with serum concentrations of the active sulfide metabolite comparable to those in patients with no hepatic impairment. The patient who was not affected had less effects on urinary PGE2 and TxB2 and no effect on 6-keto PGFlα. In this patient, dosing with ibuprofen caused pronounced declines in all urinary prostanoids and a decrease in creatinine clearance. Two other patients treated with ibuprofen and one treated with naproxen also suffered decrements in all parameters. In conclusion, sulindac had suppressant effects on renal prostanoids associated with declines in creatinine clearance in these patients with cirrhosis, indicating a need for similar cautions with its use as with other NSAIDs.

研究 Fallot四徴症の術前後の血小板,カテコールアミン,プロスタノイドの変動

研究 Fallot四徴症の術前後の血小板,カテコールアミン,プロスタノイドの変動