心电图对肺动脉高压的诊断价值探讨

目的 参照右心导管检查结果,评价常规12导联心电图在肺动脉高压诊断中的应用价值.方法 入选超声心动图估测肺动脉收缩压≥36 mm Hg(1 mm Hg=0.133 kPa)的64例疑诊肺动脉高压患者为研究对象,右心导管检查前30 min行12导联心电图检查.根据右心导管检查结果排除肺动脉高压者26例,确诊肺动脉高压者38例(特发性肺动脉高压23例,结缔组织病相关性肺动脉高压15例).比较两组间心电图参数差异.通过ROC曲线计算心电图各指标诊断肺动脉高压的敏感性、特异性、阳性预测值及阴性预测值.采用Spearman相关性计算肺动脉高压组心电图参数与血液动力学指标相关性.结果 心电图诊断右心室肥大的各指标在肺动脉高压组中的发生率显著高于排除肺动脉高压组.Ⅰ导联S波振幅＞0.21 mV、QRS电轴＞87°、R_(v1) + S_(v5)＞0.76 mV诊断肺动脉高压的敏感性分别为89%、86%、84%,特异性分别为81%、92%、83%.采用Spearman相关性分析显示,QRS电轴与肺动脉平均压的相关性最高(r=0.75,P＜0.001);R_(v1) + S_(v5)与肺血管阻力的相关性最高(r=0.74,P＜0.001);R_(v1) + S_(v5)和I导联S波振幅与心指数相关性较高(r=-0.62,P＜0.001).结论 常规12导联心电图检查在肺动脉高压筛查中有重要价值,Ⅰ导联S波振幅＞0.21 mV、QRS电轴＞87°、R_(v1) + S_(v5)＞0.76 mV等右心室肥大征象时应考虑到肺动脉高压可能.QRS电轴、R_(v1) + S_(v5)以及Ⅰ导联S波振幅对评估肺动脉高压患者血液动力学受损的严重程度有临床意义.     

Echocardiographic predictors of adverse outcomes in primary pulmonary hypertension

OBJECTIVES: The aim of this study was to evaluate the relationships between echocardiographic findings and clinical outcomes in patients with severe primary pulmonary hypertension (PPH).BACKGROUND: Primary pulmonary hypertension is associated with abnormalities of right heart structure and function that contribute to the poor prognosis of the disease. Echocardiographic abnormalities associated with PPH have been described, but the prognostic significance of these findings remains poorly characterized. METHODS: Echocardiographic studies, invasive hemodynamic measurements and 6-min walk tests were performed and outcomes prospectively followed in 81 patients with severe PPH. Subjects were participants in a 12-week randomized trial examining the effects of prostacyclin plus conventional therapy compared with conventional therapy alone. RESULTS: During the mean follow-up period of 36.9 +/- 15.4 months, 20 patients died and 21 patients underwent transplantation. Pericardial effusion (p = 0.003) and indexed right atrial area (p = 0.005) were predictors of mortality. Pericardial effusion (p = 0.017), indexed right atrial area (p = 0.012) and the degree of septal shift in diastole (p = 0.004) were predictors of a composite end point of death or transplantation. In multivariable analyses incorporating clinical, hemodynamic and echocardiographic variables, pericardial effusion and an enlarged right atrium remained predictors of adverse outcomes. Six-minute walk results, mixed venous oxygen saturation and initial treatment randomization were also independently associated with a poor prognosis. CONCLUSIONS: Pericardial effusion, right atrial enlargement and septal displacement are echocardiographic abnormalities that reflect the severity of right heart failure and predict adverse outcomes in patients with severe PPH. These characteristics may help identify patients appropriate for more intensive medical therapy or earlier transplantation.     

Ambrisentan therapy for pulmonary arterial hypertension

OBJECTIVES: The purpose of this study was to examine the efficacy and safety of four doses of ambrisentan, an oral endothelin type A receptor-selective antagonist, in patients with pulmonary arterial hypertension (PAH). BACKGROUND: Pulmonary arterial hypertension is a life-threatening and progressive disease with limited treatment options. Endothelin is a vasoconstrictor and smooth muscle cell mitogen that plays a critical role in the pathogenesis and progression of PAH. METHODS: In this double-blind, dose-ranging study, 64 patients with idiopathic PAH or PAH associated with collagen vascular disease, anorexigen use, or human immunodeficiency virus infection were randomized to receive 1, 2.5, 5, or 10 mg of ambrisentan once daily for 12 weeks followed by 12 weeks of open-label ambrisentan. The primary end point was an improvement from baseline in 6-min walk distance (6MWD); secondary end points included Borg dyspnea index, World Health Organization (WHO) functional class, a subject global assessment, and cardiopulmonary hemodynamics. RESULTS: At 12 weeks, ambrisentan increased 6MWD (+36.1 m, p < 0.0001) with similar and statistically significant increases for each dose group (range, +33.9 to +38.1 m). Improvements were also observed in Borg dyspnea index, WHO functional class, subject global assessment, mean pulmonary arterial pressure (-5.2 mm Hg, p < 0.0001), and cardiac index (+0.33 l/min/m2, p < 0.0008). Adverse events were mild and unrelated to dose, including the incidence of elevated serum aminotransferase concentrations >3 times the upper limit of normal (3.1%). CONCLUSIONS: Ambrisentan appears to improve exercise capacity, symptoms, and hemodynamics in patients with PAH. The incidence and severity of liver enzyme abnormalities appear to be low.     

Big endothelin-1 and endothelin-1 plasma levels are correlated with the severity of primary pulmonary hypertension.

STUDY OBJECTIVES: Primary pulmonary hypertension (PPH) is a rare disease of unknown etiology that is characterized by a poor prognosis. This study was undertaken to investigate possible correlations between endothelin (ET)-1 and big ET-1 plasma levels and the severity of PPH. PATIENTS: Sixteen consecutive patients with PPH were included. INTERVENTIONS: Hemodynamics of patients with PPH were measured by right-heart catheterization, and a 6-min walk test was performed. MEASUREMENTS: Plasma levels of the biologically active peptide ET-1 and its precursor big ET-1 were determined in blood samples from the pulmonary artery, peripheral artery, and peripheral vein by radioimmunoassay. RESULTS: A strong correlation was shown between pulmonary vascular resistance, mean pulmonary artery pressure, cardiac output, cardiac index, 6-min walk data, and elevated plasma levels of big ET-1 as well as mature ET-1 plasma levels at all sites of blood sampling (p < 0.01 and p < 0.05, respectively). CONCLUSIONS: Levels of circulating ET-1 might become a prognostic marker for patients with PPH and serve as a tool for the selection of patients who may benefit from treatment with ET-receptor antagonists.     

Oral sildenafil as long-term adjunct therapy to inhaled iloprost in severe pulmonary arterial hypertension

OBJECTIVES: We sought to investigate the impact of adjunct sildenafil on exercise capacity and hemodynamic parameters in patients with pulmonary arterial hypertension (PAH) who fulfilled predefined criteria of deterioration despite ongoing treatment with inhaled iloprost. BACKGROUND: Inhaled iloprost is an effective therapy in PAH. The phosphodiesterase-5 inhibitor sildenafil exerts pulmonary vasodilation and may amplify prostanoid efficacy. METHODS: Of 73 PAH patients receiving long-term inhaled iloprost treatment, 14 fulfilled criteria of deterioration unresponsive to conventional treatment. These patients received adjunct oral sildenafil over a period of nine to 12 months, leaving the inhalative iloprost regimen unchanged. RESULTS: Before iloprost therapy, the baseline 6-min walking distance was 217 +/- 31 m (mean +/- SEM), with an improvement to 305 +/- 28 m within the first three months of iloprost treatment and a subsequent decline to 256 +/- 30 m after 18 +/- 4 months. Adjunct therapy with sildenafil reversed the deterioration and increased the 6-min walk distance to 346 +/- 26 m (p = 0.002, Wilcoxon test) at three months of combined therapy, with a sustained efficacy up to 12 months (349 +/- 32 m, p = 0.002). The distribution of New York Heart Association functional classes (IV/III/II) improved from September 9, 2000, before sildenafil, to January 8, 2003, after nine to 12 months with sildenafil. All hemodynamic variables changed favorably: pulmonary vascular resistance decreased from 2,494 +/- 256 before sildenafil to 1,950 +/- 128 dynes.s.cm(-5).m(2) after three months of adjunct sildenafil (p = 0.036). Two patients died of severe pneumonia during the period of combined therapy. No further serious adverse events occurred. CONCLUSIONS; In patients with severe PAH deteriorating despite ongoing prostanoid treatment, long-term adjunct oral sildenafil improves exercise capacity and pulmonary hemodynamics. A combination of prostanoids and sildenafil is an appealing concept for future treatment of pulmonary hypertension.     

Hyperuricemia in severe pulmonary hypertension

STUDY OBJECTIVE: Hyperuricemia occurs frequently in patients with myeloproliferative and lymphoproliferative disorders and in patients with congenital heart disease associated with polycythemia. Whether hyperuricemia is common in patients with severe pulmonary hypertension is not known. DESIGN, PATIENTS, MEASUREMENTS: In the Pulmonary Hypertension Center at the University of Colorado Health Sciences Center between September 1991 and August 1997, 442 consecutive patients were evaluated with right heart catheterization; 191 patients also had a measurement of the serum uric acid (UA) in close temporal proximity to the hemodynamic evaluation. RESULTS: Of the 191 patients with a complete data set, 99 patients had primary pulmonary hypertension (PPH) and 92 had secondary pulmonary hypertension. For the entire cohort with severe pulmonary hypertension (n = 191), there was a positive correlation between the natural logarithm of the serum UA (lnUA) and the mean right atrial pressure (RAP; r = 0.47; p < 0.001). When analyzed separately, the correlation between lnUA and RAP was stronger in the patients with PPH (r = 0.642; p < 0.001). This correlation cannot be explained by diuretic use or impaired hepatocellular function. Neither mean pulmonary artery pressure nor cardiac output was as well correlated with the RAP when compared with the lnUA. Some patients with PPH had serum UA measurements repeated during treatment with chronic IV prostacyclin infusion. Eleven of these 18 patients (61%) demonstrated a decrease in serum UA during prostacyclin treatment. CONCLUSION: There is a positive correlation between the RAP elevation and the serum UA levels in patients with PPH. Serum UA levels drop in some, but not all PPH patients during chronic prostacyclin infusion therapy.     

法舒地尔治疗先天性心脏病相关性重度肺动脉高压短期疗效观察

目的 探讨法舒地尔治疗先天性心脏病相关性重度肺动脉高压短期应用的有效性及安全性。方法 入选2011年1月2012年8月我科住院的先天性心脏病相关性重度肺动脉高压患者,法舒地尔60 mg静脉滴注,每天2次,连续用药14 d后观察6分钟步行距离、血流动力学参数、超声心动图指标以及血浆N末端脑钠尿肽前体(NTpro BNP)变化情况。结果 共纳入21(男4,女17)例患者,年龄16~54(32±14)岁;用药14 d后6分钟步行距离由(445±49)m显著增加至(471±40)m,差异有统计学意义;且WHO肺动脉高压心功能分级显著改善(P<0.05)。血浆NT-pro BNP亦明显下降,从(788±623)pg/ml降低至(464±393)pg/ml(P<0.05)。右房平均压从(6.1±2.3)mm Hg降低至(5.2±1.8)mm Hg(P<0.05);右向左分流量从(23±16)%明显减少至(18±16)%(P<0.05);而肺动脉平均压、肺血管阻力、体肺循环血流量比值、体肺循环阻力比值、股动脉氧饱和度、心脏指数等指标虽无显著统计学差异,但较用药前均有所改善,仅体循环压力及阻力均无统计学差异。结论 法舒地尔短期内应用可显著提高先天性心脏病相关重度肺动脉高压患者的运动耐量、WHO肺动脉高压心功能分级,有效改善肺动脉高压的血流动力学指标,而且安全性与耐受性良好。     

Primary pulmonary hypertension in cirrhosis of liver.

BACKGROUND: Primary pulmonary hypertension (PPH) is a grave association of portal hypertension, and is potentially fatal in liver transplant candidates. AIM: To investigate the prevalence of PPH among cirrhotics with portal hypertension. METHODS: 43 cirrhotics with portal hypertension (Child B 22, C 14), after screening for cardiopulmonary diseases, were evaluated by hemodynamic study. RESULTS: PPH was detected in 2 cases (4.7%), both in Child B, hepatitis B and C viruses being the etiologies. Neither had portal axis thrombosis. Two other cases also had pulmonary hypertension, but with high pulmonary capillary wedge pressure (PCWP). The 41 cases without and 2 cases with PPH had, respectively, mean pulmonary artery pressure (MPAP) 16.3 (5.9) mmHg, 26 mmHg and 33 mmHg; PCWP 11.5 (6.7) mmHg, 12 mmHg and 11 mmHg; transpulmonary pressure gradient 4.8 (2.6) mmHg (n = 27), 14 mmHg and 22 mmHg; and pulmonary vascular resistance 80.2 (55.8) dyne.sec.cm-5 (n = 27), 155.6 dyne.sec.cm-5 and 366.7 dyne.sec.cm-5. No correlation of MPAP was found with either Child-Pugh scoring (r2 = 0.0347) or with hepatic venous pressure gradient (r2 = 0.0021). CONCLUSION: PPH has a prevalence of 4.7% among cirrhotics with portal hypertension; it bears no relation with severity of liver disease.     

Beraprost therapy for pulmonary arterial hypertension

OBJECTIVES: The purpose of this study was to assess the safety and efficacy of the oral prostacyclin analogue beraprost sodium during a 12-month double-blind, randomized, placebo-controlled trial in patients with pulmonary arterial hypertension (PAH). BACKGROUND: Pulmonary arterial hypertension is a progressive disease that ultimately causes right heart failure and death. Despite the risks from its delivery system, continuous intravenous epoprostenol remains the most efficacious treatment currently available. METHODS: A total of 116 patients with World Health Organization (WHO) functional class II or III primary pulmonary hypertension or PAH related to either collagen vascular diseases or congenital systemic to pulmonary shunts were enrolled. Patients were randomized to receive the maximal tolerated dose of beraprost sodium (median dose 120 microg four times a day) or placebo for 12 months. The primary end point was disease progression; i.e., death, transplantation, epoprostenol rescue, or >25% decrease in peak oxygen consumption (VO(2)). Secondary end points included exercise capacity assessed by 6-min walk test and peak VO(2), Borg dyspnea score, hemodynamics, symptoms of PAH, and quality of life. RESULTS: Patients treated with beraprost exhibited less evidence of disease progression at six months (p = 0.002), but this effect was not evident at either shorter or longer follow-up intervals. Similarly, beraprost-treated patients had improved 6-min walk distance at 3 months by 22 m from baseline and at 6 months by 31 m (p = 0.010 and 0.016, respectively) compared with placebo, but not at either 9 or 12 months. Drug-related adverse events were common and were related to the disease and/or expected prostacyclin adverse events. CONCLUSIONS: These data suggest that beneficial effects may occur during early phases of treatment with beraprost in WHO functional class II or III patients but that this effect attenuates with time.     

Antinuclear antibodies in primary pulmonary hypertension

The association of positive antinuclear antibodies with the clinical and hemodynamic features of 43 patients with primary pulmonary hypertension and 16 patients with secondary pulmonary hypertension was investigated. Each patient had determinations of antinuclear antibodies using a KB cell substrate immunofluorescent test. Of the patients with primary pulmonary hypertension, 40% had positive antinuclear antibodies at titers of 1:80 dilutions or greater. There were no differences between patients with primary pulmonary hypertension and positive antinuclear antibodies compared with those with negative antinuclear antibodies in relation to clinical or hemodynamic status. A 6% incidence rate of antinuclear antibodies was found in patients with secondary pulmonary hypertension, similar to that in the normal population. The clinical, hemodynamic, serologic and histologic similarity between patients with primary pulmonary hypertension and those with unexplained pulmonary hypertension associated with collagen vascular disorders suggests that primary pulmonary hypertension in some patients may represent a collagen vascular disease confined to the lungs. The frequency of positive antinuclear antibody tests would place primary pulmonary hypertension between rheumatoid arthritis and scleroderma in the spectrum of collagen vascular diseases. Further studies are necessary, however, before one might expect that immunosuppressive therapy would be beneficial to these patients.     

Clinical significance of brain natriuretic peptide in primary pulmonary hypertension

OBJECTIVES: The aim of this study was to investigate the potential role of brain natriuretic peptide (BNP) levels in the assessment of functional status and right heart performance in primary pulmonary hypertension (PPH). BACKGROUND: Primary pulmonary hypertension is a progressive disease leading to right heart failure and death. Right heart catheterization and maximal or submaximal exercise tests are employed to assess the course of the disease and the effect of therapeutic interventions. Additional noninvasive and reproducible parameters would be helpful to assess the status of patients with PPH. The natriuretic peptide system is up-regulated in PPH patients. Brain natriuretic peptide (BNP) is produced from the cardiac ventricles and elevated in PPH. The aim of our study was to evaluate the clinical significance of BNP in PPH patients. METHODS: Correlation analysis was performed for plasma BNP levels of 28 PPH patients and World Health Organization (WHO) functional class (WHO-class), distance walked in 6 min, peak oxygen uptake (peak Vo(2)), and oxygen pulse during spiroergometry and various hemodynamic parameters, including pulmonary vascular resistance (PVR), pulmonary artery pressure (PAP), right atrial pressure (RAP), and cardiac index. RESULTS: The BNP levels were inversely correlated with the 6-min walk (r = -0.70; p < 0.001) and peak Vo(2) (r = -0.61; p < 0.01), and positive correlation was observed with WHO-class (r = 0.79; p < 0.001). Moreover, BNP levels were also correlated to PVR (r = 0.61; p < 0.01), PAP (r = 0.48; p < 0.05), and RAP (r = 0.78; p < 0.01), and were inversely related to cardiac index (r = -0.48; p < 0.05). CONCLUSIONS: Our data suggest that plasma BNP levels are closely related to the functional impairment of PPH patients and parallel the extent of pulmonary hemodynamic changes and right heart failure. Serial measurements of plasma BNP concentrations may help improve the management of PPH patients.     

Clinical efficacy of sitaxsentan,an endothelin-A receptor antagonist,in patients with pulmonary arterial hypertension: open-label pilot study

STUDY OBJECTIVES: To evaluate the safety and efficacy of sitaxsentan, an endothelin-A receptor antagonist, in a 12-week, open-label trial of patients with pulmonary arterial hypertension (PAH). PATIENTS: Six children and 14 adults with New York Heart Association (NYHA) functional class II, III, or IV primary pulmonary hypertension or PAH associated with either congenital systemic-to-pulmonary shunts or collagen vascular disease were enrolled. MEASUREMENTS: Sitaxsentan was administered orally at 100 to 500 mg bid for 12 weeks. Cardiopulmonary hemodynamics via cardiac catheterization were obtained at baseline and week 12. Six-minute walk test distance was measured at baseline, week 6, and week 12. RESULTS: Sitaxsentan treatment resulted in significant improvement in exercise capacity as assessed by the 6-min walk distance (baseline [mean +/- SD], 466 +/- 132 m; week 12, 515 +/- 141 m, n = 20, p = 0.006). Mean pulmonary artery pressure and pulmonary vascular resistance index also improved (63 +/- 20 to 52 +/- 22 mm Hg, n = 17, p = 0.0002; and 20 +/- 11 to 14 +/- 13 U x m(2), n = 17, p = 0.008, respectively). Serious adverse events included two cases of acute hepatitis (fatal in one patient). CONCLUSIONS: Patients with NYHA functional class II, III, or IV PAH showed a significant improvement in exercise capacity and cardiopulmonary hemodynamics over a 12-week period of treatment with sitaxsentan, an endothelin-A receptor antagonist. Further investigation is warranted to evaluate the safety and efficacy of sitaxsentan in patients with PAH.     

Investigation of pulmonary hypertension

Pulmonary hypertension (PH) is defined by a mean pulmonary artery pressure (PAPm) superior than 25mmHg at rest or superior than 30mmHg with exercise. The classification of PH differentiates between "secondary" PH which results from a well-known disease, such as PH due to thromboembolic disease (obstructive PH), left cardiac failure (passive PH), or chronic respiratory diseases (hypoxic PH), and pulmonary arterial hypertension (PAH). PAH is a rare disease characterized by a progressive increase of pulmonary vascular resistance leading to right ventricular failure. PAH is classified as idiopathic, familial, or associated with various conditions (connective tissue diseases, congenital heart diseases with systemic-to-pulmonary shunts, portal hypertension, infection with the human immunodeficiency virus, or appetite-suppressant drugs). Transthoracic Doppler echocardiography is the investigation of choice for non invasive detection of PAH but right-heart catheterization is necessary to confirm the diagnosis of PAH and determine its mechanism. Pulmonary function tests and chest CT scan may detect an underlying chronic pulmonary disease (hypoxic PH). Lung perfusion scan and contrast-enhanced chest spiral CT scan can lead to the diagnosis of thromboembolic PH, which is to be confirmed by pulmonary angiography. Assessment of the severity of PH is based on clinical parameters (NYHA, right heart failure), functional tests (six-minute walk test), echocardiography and hemodynamics. Characterization of PH is essential in the management of PH because it determines the appropriate treatment: an etiological treatment in passive, obstructive or hypoxemic PH, or vasodilatator and antiproliferative therapies in PAH.     

Primary pulmonary hypertension in Israel: a national survey

OBJECTIVES: To characterize the incidence of patients with primary pulmonary hypertension (PPH) in Israel and their outcomes. METHODS: We have evaluated retrospectively all the patients in Israel in whom PPH was diagnosed between the years 1988 and 1997. We looked at medical history, hemodynamic data, pulmonary function and gas exchange, and demographic variables. Patients were followed up for survival until November 1997. Life table analysis and Kaplan-Meier statistics were used to estimate the overall survival distribution. Regression analysis was used to examine the relations between survival and selected variables. RESULTS: Overall, we found 44 patients with PPH. The estimated incidence of PPH in Israel is 1.4 new cases per year per million population. The mean (+/- SD) age at diagnosis was 43 +/- 13 years. In the Jewish population, PPH was more frequent among immigrants from Europe and the United States. The mean interval from the onset of symptoms to diagnosis was 3 years (median, 2 years). The median survival time was 4 years. The 1-year, 3-year, and 5-year survival rates were 82%, 57%, and 43%, respectively. The major variables influencing the survival rate were the following: interval from symptom onset to diagnosis; and hemodynamic measurements (ie, mean pulmonary artery pressure, mean right atrial pressure, and cardiac index). In comparison to rates discerned from the National Institutes of Health registry data, the survival rate in Israel is somewhat better and prognosis is influenced by similar hemodynamic variables. CONCLUSION: PPH is a rare and fatal disease in Israel. New therapeutic modalities such as prostacyclin therapy and lung transplantation may improve survival among patients with this malignant disease.     

Pulmonary hemodynamic and gas exchange effects of various oxygen concentrations in patients with severe pulmonary hypertension primarily affecting the pulmonary vasculature]

The aim of this study was to evaluate pulmonary hemodynamic and gas exchange response to oxygen inhalation in patients with severe pulmonary hypertension primarily affecting the pulmonary vasculature. This study included 7 patients with primary pulmonary hypertension (PPH), 11 with pulmonary hypertension related to collagen vascular diseases (CoPH), and 18 with chronic thromboembolic pulmonary hypertension (CTEPH). All patients had mean pulmonary arterial pressure (PPAm) of greater than 25 mm Hg. We divided the patients into two groups: a PPH + CoPH group comprising the 7 PPH and 11 CoPH patients, and the CTEPH group. We measured cardiopulmonary variables after 10 min inhalation of various oxygen concentrations (FiO2 0.24, 0.28, 0.4, 1.0). In the PPH + CoPH group, PPAm significantly decreased after the inhalation of oxygen concentrations of 40% or more. This was associated with a significant reduction in pulmonary arteriolar resistance (PAR), and suggested active pulmonary vasodilation was caused by oxygen inhalation. In the CTEPH group, on the other hand, PPAm significantly decreased after the inhalation of oxygen concentrations of 28% or more, apparently in association with a significant fall of cardiac output. However, PAR was unchanged regardless of the inspired oxygen concentration, indicating an absence of pulmonary vasodilation in the CTEPH group. When breathing room air, 7 patients in the PPH + CoPH group (38.9%) and 10 in the CTEPH group (55.6%) demonstrated mixed venous oxygen tension (PvO2) values of less than 35 Torr. Extra attention should be paid to PvO2 when administering oxygen therapy to patients with severe pulmonary hypertension.     

Vasoresponsiveness of sarcoidosis-associated pulmonary hypertension

OBJECTIVE: To assess short-term and long-term responses to treatment with pulmonary vasodilators in patients with sarcoidosis-related pulmonary hypertension. METHODS: A prospective, observational study was performed on eight patients with moderate-to-severe sarcoidosis-related pulmonary hypertension. Patients underwent a short-term vasodilator trial, using inhaled nitric oxide (iNO), IV epoprostenol, and/or oral calcium-channel blockers. A favorable short-term response was considered a > or = 20% decrease in pulmonary vascular resistance (PVR). Five patients received long-term treatment with iNO (with one patient receiving epoprostenol in addition) and underwent follow-up hemodynamic and/or 6-min walk testing. Two patients received long-term treatment with calcium-channel blockers. RESULTS: Baseline (+/- SE) mean pulmonary artery pressure (mPAP) was 55 +/- 4 mm Hg and PVR was 896 +/- 200 dyne.s.cm(-5). A favorable short-term response was seen in seven of eight patients receiving iNO, four of six patients receiving epoprostenol, and two of five patients receiving calcium-channel blockers. With iNO, PVR decreased 31 +/- 5% (p = 0.006) and mPAP decreased 18 +/- 4% (p = 0.003); with epoprostenol, PVR decreased 25 +/- 6% (p = 0.016) and mPAP decreased 6 +/- 2% (p = not significant). Decreased systemic vascular resistance was the only significant response to treatment with calcium-channel blockers. Follow-up 6-min walk test results improved in all five patients receiving long-term treatment with iNO. Follow-up hemodynamic responses in three patients showed preserved vasoresponsiveness. These three patients subsequently died, as did the two patients receiving calcium-channel blockers. The two remaining patients continue to receive iNO. CONCLUSION: In the short term, pulmonary hypertension in patients with sarcoidosis is responsive to treatment with pulmonary vasodilators; these patients may benefit from long-term iNO therapy.     

先天性心脏病重度肺动脉高压对腺苷的急性反应

目的: 探讨先天性心脏病（CHD）并发重度肺动脉高压（PAH）患者对腺苷的急性血流动力学反应。方法: 对25例CHD并发严重PAH患者采用腺苷进行急性肺血管扩张试验,检测其血流动力学指标变化。结果: 25例患者中,仅7例患者达到最大剂量无不良反应。给予腺苷后,肺动脉压力和主动脉压力均显著降低（P<0.05）,股动脉血氧饱和度,肺血管阻力,肺循环/体循环血流量比值,肺动脉/主动脉平均压比值,肺血管阻力/体循环阻力比值（Rp/Rs）均无明显变化。没有患者肺动脉平均压降至40 mmHg以下。12例患者肺血管阻力和Rp/Rs降低10%以上,与另外13例患者比较,二者在年龄,肺动脉压力,肺动脉/主动脉平均压比值,肺循环/体循环血流量比值,肺血管阻力和Rp/Rs等方面均无明显差异。结论: 在CHD并发重度PAH患者中,采用腺苷进行急性肺血管扩张试验可引起肺动脉和体循环压力同步降低,而对肺血管阻力无明显影响。     

Compassionate use of continuous prostacyclin in the management of secondary pulmonary hypertension: a case series.

BACKGROUND: Treatment of patients with secondary pulmonary hypertension has been unsatisfactory. OBJECTIVE: To describe exercise capacity, functional class, and hemodynamic variables after long-term intravenous infusion of prostacyclin in patients with secondary pulmonary hypertension. DESIGN: Case series. SETTING: Academic referral center. PATIENTS: 33 patients with secondary, precapillary pulmonary hypertension (New York Heart Association class III or IV). INTERVENTION: Continuous intravenous prostacyclin administered by portable infusion pump on a compassionate-use basis. MEASUREMENTS: Functional class, treadmill time, and hemodynamic variables. RESULTS: Patients were followed for an average of 12.7 +/- 5.6 months. Exercise tolerance and New York Heart Association class improved in each patient. The duration of treadmill exercise increased from 186 seconds to 491 seconds, an increase of 305 seconds (95% CI, 194 to 417 seconds; P < 0.001). Mean pulmonary artery pressure decreased from 60 mm Hg to 46 mm Hg, a decrease of 14 mm Hg (CI, 9 to 19 mm Hg; P < 0.001). Cardiac output increased from 3.90 L/min to 6.30 L/min, an increase of 2.40 L/min (CI, 1.56 to 3.25 L/min; P < 0.001). The pulmonary vascular resistance decreased from 1143 dynes x s/cm5 to 575 dynes x s/cm5, a decrease of 567 dynes x s/cm5 (CI, 407 to 727 dynes x s/cm5; P < 0.001). Patients with collagen vascular disease, congenital heart disease, and portopulmonary hypertension were analyzed with other patients and separately. All groups had a statistically significant reduction in mean pulmonary artery pressure and a statistically significant increase in cardiac output. CONCLUSION: Intravenous prostacyclin may be effective in the treatment of patients with certain types of secondary pulmonary hypertension.     

Plasma beta-endorphin and adenosine concentration in pulmonary hypertension

To determine whether beta-endorphin plays a role in the regulation of pulmonary vascular tone in patients with pulmonary hypertension, we investigated the relations between hemodynamics and beta-endorphin and adenosine concentrations in 3 clinical situations: (1) normal hemodynamics (7 subjects, mean pulmonary artery [PA] pressure 18.5 +/- 1 mm Hg); (2) moderate pulmonary hypertension secondary to chronic obstructive pulmonary disease (COPD) (8 patients, mean PA pressure 31 +/- 3 mm Hg); and (3) severe primary pulmonary hypertension (PPH) (8 patients, mean PA pressure 70 +/-5 mm Hg). Plasma beta-endorphin and adenosine were measured in a distal PA and in the femoral artery in room air and during oxygen inhalation. Beta-endorphin levels were similar in the pulmonary and systemic circulations. No difference was observed between patients with COPD and PPH, but relative to controls, both had significantly higher beta-endorphin levels. Pulmonary adenosine was significantly lower in patients with pulmonary hypertension than in controls (-60% in COPD [p <0.005] and -70% in PPH [p <0.001]). Pure oxygen administration significantly decreased adenosine and beta-endorphin levels, much more so in patients with COPD and PPH. We found a negative correlation between beta-endorphin and adenosine concentrations (r = -0.751, p <0.001): the higher the adenosine, the lower the beta-endorphin level. These observations suggest that because adenosine release by pulmonary vascular endothelium is reduced in pulmonary hypertension, the resulting worsened hypoperfusion and tissue oxygenation may cause increased beta-endorphin release.     

Prostanoids for pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a severe condition that markedly reduces exercise capacity and survival in the affected patient population. PAH includes primary pulmonary hypertension (PPH) and pulmonary hypertension associated with collagen vascular diseases, congenital systemic-to-pulmonary shunts, portal hypertension and HIV infection. All these conditions share virtually identical obstructive pathologic changes of the pulmonary microcirculation and probably similar pathobiologic processes. The pathophysiology is characterized by a progressive increase in pulmonary vascular resistance, leading to right ventricular failure and death. Prostacyclin is an endogenous substance that is produced by vascular endothelial cells and induces vasodilatation, inhibition of platelet activity, and antiproliferative effects. A dysregulation of prostacyclin metabolic pathways has been shown in patients with PAH and this represents the rationale for the exogenous therapeutic administration of this substance. The clinical use of prostacyclin in patients with PAH has been made possible by the synthesis of stable analogs that possess different pharmacokinetic properties but share similar pharmacodynamic effects. Experience in humans has been initially collected with epoprostenol, which is a synthetic salt of prostacyclin. Epoprostenol has a short half-life in the circulation and requires continuous administration by the intravenous route by means of infusion pumps and permanent tunnelized catheters. In addition, epoprostenol is unstable at room temperature, and the complex delivery system required is associated with several adverse effects and potentially serious complications. For these reasons, alternatives to intravenous epoprostenol have been sought and this has led to the development of analogs that can be administered subcutaneously (treprostinil), orally (beraprost sodium) or by inhalation (iloprost). Three unblinded clinical trials and several uncontrolled trials have shown that treatment with epoprostenol improved symptoms and exercise capacity in New York Heart Association (NYHA) class III and IV PAH patients and also survival in patients with PPH. Subcutaneous treprostinil improved symptoms, exercise, hemodynamics and clinical events in the largest clinical trial ever performed in PAH, but local infusion site reactions limited efficacy in a proportion of patients. Oral beraprost sodium improved exercise capacity only in patients with PPH and is the only prostacyclin analog that has also been tested in NYHA class II patients. Inhaled iloprost has improved symptoms, exercise capacity and clinical events in patients with PAH and inoperable chronic thromboembolic pulmonary hypertension. The favorable effects of prostanoids observed in all studies coupled with different profiles of adverse events and tolerability for each prostacyclin analog allow the unique opportunity to select the most appropriate compound for the individual patient with PAH.