Primary pulmonary hypertension

Undiagnosed connective tissue diseases: High prevalence in pulmonary arterial hypertension patients

Among different subgroups of pulmonary arterial hypertension (PAH), those associated with connective tissue diseases (CTDs) have distinct hemodynamic and prognostic features; a correct etiologic diagnosis is thus mandatory.To estimate frequency and prognosis of previously undiagnosed CTDs in a suspect idiopathic (i) PAH cohort.Consecutive patients with PAH confirmed by right heart catheterization referred at the Cardiology Division of our Hospital without a previous rheumatological assessment or the occurrence of other conditions explaining PAH were checked for CTD by a clinical, laboratory, and instrumental evaluation. Survival in each group has also been analyzed.In our study 17 of 49 patients were classified as CTD-PAH, corresponding to a prevalence (95% CI) of 34.7% (21.7-49.6%). ANA positivity had 94% (71.3-99.9%) sensitivity and 78.1% (60-90.7%) specificity for a diagnosis of CTD-PAH; Raynaud phenomenon (RP) showed 83.3% (51.6-97.9%) sensitivity and 100% (90.5-100%) specificity for the diagnosis of Systemic Sclerosis (SSc)-PAH. At diagnosis, SSc patients were older and had a lower creatinine clearance compared with iPAH and other CTD-PAH. After a median follow-up of 44 (2-132) months, 18 of 49 (36.7%) patients died: 31.2% in the iPAH group, 20% in the CTD-, and 58.3% in the SSc-PAH group. Mortality was significantly higher in SSc-PAH (HR 3.32, 1.11-9.95, P <0.05) versus iPAH.We show a high prevalence of undiagnosed CTDs in patients with iPAH without a previous rheumatological assessment. All patients with RP were diagnosed with SSc. Our data stress the importance of a rheumatological assessment in PAH, especially because of the unfavorable prognostic impact of an associated SSc.

Wall shear stress is decreased in the pulmonary arteries of patients with pulmonary arterial hypertension: An image-based, computational fluid dynamics study

Previous clinical studies in pulmonary arterial hypertension (PAH) have concentrated predominantly on distal pulmonary vascular resistance, its contribution to the disease process, and response to therapy. However, it is well known that biomechanical factors such as shear stress have an impact on endothelial health and dysfunction in other parts of the vasculature. This study tested the hypothesis that wall shear stress is reduced in the proximal pulmonary arteries of PAH patients with the belief that reduced shear stress may contribute to pulmonary endothelial cell dysfunction and as a result, PAH progression. A combined MRI and computational fluid dynamics (CFD) approach was used to construct subject-specific pulmonary artery models and quantify flow features and wall shear stress (WSS) in five PAH patients with moderate-to-severe disease and five age- and sex-matched controls. Three-dimensional model reconstruction showed PAH patients have significantly larger main, right, and left pulmonary artery diameters (3.5 ± 0.4 vs. 2.7 ± 0.1 cm, P = 0.01; 2.5 ± 0.4 vs. 1.9 ± 0.2 cm, P = 0.04; and 2.6 ± 0.4 vs. 2.0 ± 0.2 cm, P = 0.01, respectively), and lower cardiac output (3.7 ± 1.2 vs. 5.8 ± 0.6 L/min, P = 0.02.). CFD showed significantly lower time-averaged central pulmonary artery WSS in PAH patients compared to controls (4.3 ± 2.8 vs. 20.5 ± 4.0 dynes/cm(2), P = 0.0004). Distal WSS was not significantly different. A novel method of measuring WSS was utilized to demonstrate for the first time that WSS is altered in some patients with PAH. Using computational modeling in patient-specific models, WSS was found to be significantly lower in the proximal pulmonary arteries of PAH patients compared to controls. Reduced WSS in proximal pulmonary arteries may play a role in the pathogenesis and progression of PAH. This data may serve as a basis for future in vitro studies of, for example, effects of WSS on gene expression.

Pulmonary veno-occlusive disease

A 50-year-old female patient with a long history of Raynaud's phenomenon and rapidly deteriorating right-sided cardiac failure is presented. Pulmonary veno-occlusive disease was diagnosed from typical clinical and hemodynamic findings using a Swan-Ganz balloon catheter. The diagnosis was definitely confirmed at necropsy. There was no clinical, laboratory, or histologic evidence of a connective tissue disease.

Use of noninvasive tools in primary pulmonary hypertension to assess the correlation of right ventricular function with functional capacity and to predict outcome

Most patients with Primary Pulmonary Hypertension (PPH) have severe exertional limitation which ultimately leads to right heart failure and death. The purpose of the study was to assess the correlation between right ventricular (RV) systolic and diastolic noninvasive variables and exercise tolerance, as well as the predictors of adverse outcome in treated patients.

METHODS

We prospectively studied 29 patients, 17 with PPH and 12 with PPH due to collagen disease. RV parameters were assessed by echocardiography and Radionuclide ventriculography. Pulmonary function and clinical profile were assessed by 6 min walk test and NYHA class. The patients were followed-up during 2 years for cardiac death and cardiac deterioration.

RESULTS

Mean age was 51 +/- 15 years, 22 (78%) women. NYHA class1 in 2 pts, class 2 in 17, class 3 in 8 and class 4 in 2 pts. Pulmonary function (DLCO) was low in 25 (86%) pts, mean 22 +/- 48%. Six minutes walk distance was 358 +/- 132 m, RVEF was 34 +/- 11% (range 16-51%). Among RV variables, RVEF, RA area and TR were independently correlated to 6 min walk. Within follow up of 2 years, there were 10 patients with adverse outcome (4 deaths and 6 deteriorated to NYHA class 3 and 4). Among all clinical and noninvasive variables, RVEF only was correlated to adverse outcome.

CONCLUSION

The noninvasive tests of RVEF, RA size and TR were closely correlated to exercise tolerance. However, among the various clinical, functional and RV variables, RVEF was the only variable correlated with adverse outcome in pts with PPH.

[Reference figures for pulmonary artery pressures after effective treatment of Graves' disease]

We report the case of a 48-year-old woman with a diagnosis of pulmonary hypertension and hyperthyroidism (Graves' disease) in whom pulmonary artery pressures became normal after treatment of thyroid disease. The possible pathogenic mechanisms involved in this association include the presence of hyperdynamic heart failure and/or the presence of immune alterations underlying both conditions.

Pulmonary function test abnormalities in pulmonary vascular disease and chronic heart failure

Diagnostic criteria based on pulmonary function testing for pulmonary vascular disease and CHF are imprecise. Although these tests constitute a necessary part of the work-up of a patient with dyspnea, additional studies are required to obtain a final diagnosis in the setting of cardiopulmonary vascular disease. In contrast, specific pulmonary function tests may offer an objective means of assessing severity of dysfunction resulting from pulmonary hypertension or CHE Serial measurements of pulmonary function offer insight into general and specific patterns of cardiopulmonary vascular disease and are useful in evaluating response to treatment.

Nocturnal hypoxemia is common in primary pulmonary hypertension

STUDY OBJECTIVE

Unsuspected sleep-related respiratory events are common in patients with severe pulmonary disease. Sleep in patients with primary pulmonary hypertension (PPH) has not been studied (to our knowledge). The purpose of this study was to measure the prevalence of respiratory disturbances and nocturnal hypoxemia during the sleep of patients with PPH.

SETTING

Tertiary-care referral hospital.

DESIGN

Retrospective review.

PATIENTS

Thirteen patients with PPH.

MEASUREMENTS

All patients underwent a single-night comprehensive polysomnogram study. Patients who spent > 10% of the total sleep time with oxygen saturation by pulse oximetry (SpO(2)) at < 90% or who needed oxygen to maintain their SpO(2) level at > 90% were classified as nocturnal desaturators. Analysis was performed to determine which clinical variables (ie, demographics, body mass index, spirometry, diffusion capacity, right heart catheterization pressures, 6-min walk test, arterial blood gas levels, resting and walking SpO(2) levels, and polysomnogram variables) would predict nocturnal desaturation. Statistical significance was considered when p values were < 0.05.

RESULTS

Of the 13 patients in the study, 10 (77%) were nocturnal desaturators. All patients had normal apnea indexes, but two had mild elevations of the hypopnea index (< 15 episodes per hour). Nocturnal desaturations occurred independently of apneas or hypopneas. Six patients who did not have O(2) titration during sleep spent > 25% of sleep time with SpO(2) < 90%. The mean (+/- SD) variables that were significantly different between desaturators (10 patients) and nondesaturators (3 patients) were FEV(1) (70.1 +/- 9.1% predicted vs 98.1 +/- 15.1% predicted, respectively; p = 0.002), resting PaO(2) (61.8 +/- 16.1 vs 90.3 +/- 2.3 mm Hg, respectively; p = 0.001), alveolar-arterial oxygen pressure difference (P[A-a]O(2)) (40.5 +/- 20.5 vs 12.2 +/- 7.2 mm Hg, respectively; p = 0.048), resting SpO(2) (91.6 +/- 5.4% vs 98.7 +/- 2.3%, respectively; p = 0.038), and walking SpO(2) (83.8 +/- 9.3% vs 95.3 +/- 1.2%, respectively; p = 0.002). The mean hemoglobin level was higher in the group of nocturnal desaturators than in the group of nondesaturators (10.43 +/- 0.31 vs 13.95 +/- 0.98 g/dL, respectively; p < 0.0001).

CONCLUSION

Seventy-seven percent of patients with PPH have significant nocturnal hypoxemia that is unrelated to apneas and hypopneas. Nocturnal desaturation occurs more frequently in patients with higher P(A-a)O(2) values and lower FEV(1) values, resting arterial PaO(2) and SpO(2) values, and walking SpO(2) values.

Survival and prognostic factors in patients with primary pulmonary hypertension

OBJECTIVES

Primary pulmonary hypertension (PPH) that affects predominantly young and productive people is a progressive fatal disease of unknown cause. The objectives of this study were to characterize mortality in patients with PPH and to investigate the factors associated with their survival.

METHODS

Thirteen patients with PPH were enrolled between 1988 and 1996 and followed-up through July 1999. Measurements at diagnosis included hemodynamic and pulmonary function variables in addition to information on demographic data and medical history.

RESULTS

1) The mean age of the patients with PPH enrolled into the study was 36.1 +/- 9.3 years with female predominance. 2) The estimated median survival was 3.4 +/- 0.6 years. 3) Decreased cardiac index was the only significant predictor of mortality (Cox proportional hazards model).

CONCLUSION

Patients with PPH have a poor survival expectancy. In this limited study with a small number of patients, mortality is largely associated with decreased cardiac index.

Effects of long-term infusion of prostacyclin on exercise performance in patients with primary pulmonary hypertension

STUDY OBJECTIVES

To determine whether long-term IV prostacyclin (PGI(2)) use improves exercise capacity in patients with primary pulmonary hypertension (PPH).

DESIGN

Cycle ergometry and the 6-min walk was used to evaluate the exercise performance of patients with PPH. The patients underwent serial exercise testing after starting continuous IV PGI(2) and were followed up for 19.5 +/- 7.5 months. Peak work, peak oxygen consumption (f1.gif" BORDER="0">O(2)), peak O(2) pulse, and distance walked in 6 min were used to evaluate performance.

BACKGROUND

PPH is characterized by medial hypertrophy and intimal proliferation of the pulmonary arterioles, leading to elevation of pulmonary artery pressure, right ventricular failure, and death. Palliative treatment consists of vasodilators, anticoagulants, cardiac glycosides, diuretics, and transplantation. PGI(2), a potent vasodilator and inhibitor of platelet aggregation, has been used for long-term treatment when conventional therapy has been unsuccessful.

PATIENTS

Sixteen patients with PPH (10 women, 6 men; mean age, 24 years).

RESULTS

At the initiation of PGI(2), peak work (+/- SD) was 35.5 +/- 11% of predicted; peak f1.gif" BORDER="0">O(2), 39 +/- 10.4%; peak O(2) pulse, 5.0 +/- 1.7 mL/min; and distance on the 6-min walk, 428 +/- 78 feet. At 18 to 27 months, peak work increased to 58.8 +/- 23% of predicted (p = 0.001), peak f1.gif" BORDER="0">O(2) increased to 52 +/- 15% of predicted (p = 0. 02), peak O(2) pulse increased to 7.1 +/- 3.0 mL/beat (p = 0.004), and performance on the 6-min walk increased to 526 +/- 62 feet (p = 0.001). There was a positive correlation between peak f1.gif" BORDER="0">O(2) and peak 6-min walk of 0.6 (p < 0.005) and between peak work and peak 6-min walk of 0.6 (p < 0.005).

CONCLUSIONS

Exercise capacity improved in our patients at up to 27 months of follow-up. Exercise testing is helpful in assessing the functional capacity of patients with PPH and may be useful in guiding therapy. Patients who deteriorate while receiving optimal conventional therapy should be considered for IV PGI(2) therapy.

Chronic pulmonary hypertension--the monocrotaline model and involvement of the hemostatic system

Monocrotaline (MCT) is a toxic pyrrolizidine alkaloid of plant origin. Administration of small doses of MCT or its active metabolite, monocrotaline pyrrole (MCTP), to rats causes delayed and progressive lung injury characterized by pulmonary vascular remodeling, pulmonary hypertension, and compensatory right heart hypertrophy. The lesions induced by MCT(P) administration in rats are similar to those observed in certain chronic pulmonary vascular diseases of people. This review begins with a synopsis of the hemostatic system, emphasizing the role of endothelium since endothelial cell dysfunction likely underlies the pathogenesis of MCT(P)-induced pneumotoxicity. MCT toxicology is discussed, focusing on morphologic, pulmonary mechanical, hemodynamic, and biochemical and molecular alterations that occur after toxicant exposure. Fibrin and platelet thrombosis of the pulmonary microvasculature occurs after administration of MCT(P) to rats, and several investigators have hypothesized that thrombi contribute to the lung injury and pulmonary hypertension. The evidence for involvement of the various components of the hemostatic system in MCT(P)-induced vascular injury and remodeling is reviewed. Current evidence is consistent with involvement of platelets and an altered fibrinolytic system, yet much remains to be learned about specific events and signals in the vascular pathogenesis.

Value of a Doppler-derived index combining systolic and diastolic time intervals in predicting outcome in primary pulmonary hypertension

Primary pulmonary hypertension is characterized by elevated pulmonary arterial pressure and vascular resistance, frequently producing right heart failure and death. Therefore, the Doppler right ventricular (RV) index, which is a measure of global RV function, could be a useful predictor of outcome in primary pulmonary hypertension. The Doppler RV index, defined as the sum of isovolumic contraction time and isovolumic relaxation time divided by ejection time, was retrospectively measured in 53 patients (38 women, aged 45 +/- 14 years) with primary pulmonary hypertension. Ejection time was measured from the pulmonary outflow velocity signal. The sum of isovolumic contraction time and isovolumic relaxation time was obtained by subtracting ejection time from the duration of tricuspid regurgitation. The Doppler RV index tended to be elevated (median 0.83) compared with normal ranges. Normal Doppler RV index was 0.28 +/- 0.04. After a mean follow-up duration of 2.9 years, 4 patients underwent lung transplantation and 30 patients died; the cause was cardiac in 28, noncardiac in 1, and uncertain in 1. Univariately, the Doppler RV index (chi-square 20.7, p <0.0001), severity of tricuspid regurgitation (chi-square 8.2, p = 0.004), treatment with calcium blockers (chi-square 6.6, p = 0.01), heart rate (chi-square 5.1, p = 0.02), and symptom status (chi-square 4.9, p = 0.03) were associated with adverse outcome (cardiac deaths and lung transplantation). However, only the Doppler RV index and treatment with calcium blockers were independent predictors within the multivariate model. Our results indicate that the Doppler RV index is a useful predictor of adverse outcome in patients with primary pulmonary hypertension.

Thromboxane inhibition and monocrotaline-induced pulmonary hypertension in rats

Monocrotaline (MCT)-induced pulmonary hypertension (PH) is a useful model for the investigation of this disorder in humans. The role of thrombocytes in the genesis of PH has already been addressed; however, the exact mechanism by which they induce PH remains to be elucidated. We investigated the effects of a thromboxane A2 (TXA2) synthase inhibitor (OKY-046) and a TXA2/prostaglandin H2 (PGH2) receptor antagonist (ONO-8809) on the development of MCT-induced PH. A single dose of MCT (60 mg/kg bodyweight; BW) was injected subcutaneously in Wistar rats 24 h after the administration of OKY-046 or ONO-8809. The TXA2 inhibitors were administered by gavage daily for 3 weeks. Urinary excretion of eicosanoids was determined by radioimmunoassay. At the end of the treatment period, the lungs, heart and kidneys were morphologically examined. The per cent medial thickness of the muscular pulmonary arteries (%MT) and the ratio of the right to the left ventricular mass including the septum (RV/LV + S) increased significantly in MCT-treated rats compared with the control rats. The %MT was attenuated by the administration of ONO-8809. Either OKY-046 or ONO-8809 attenuated the increase in RV/LV + S. In addition, both TXA2 inhibitors reduced urinary excretion of 11-dehydro-TXB2, particularly during the early phase of PH, suggesting that platelet aggregation was reduced. These findings suggest that the inhibition of TXA2 by synthase inhibition or receptor antagonism reduces or delays the development of MCT-induced PH in rats, probably by inhibiting platelet aggregation.

Acute pulmonary vasodilatory properties of amlodipine in humans with pulmonary hypertension

OBJECTIVE

Calcium antagonists are the only oral vasodilators shown to influence mortality in primary pulmonary hypertension, but the high doses required are often poorly tolerated. Amlodipine is a novel, relatively well tolerated, calcium antagonist. It has not been previously tested in humans with pulmonary hypertension.

DESIGN

Calcium antagonists are claimed to be of benefit in the 20-30% of patients who respond--that is, whose mean pulmonary artery pressure and pulmonary vascular resistance decreased by 20% after acute administration. Increasing oral doses of amlodipine (up to 40 mg) were given and haemodynamic measurements were obtained by the use of indwelling pulmonary artery catheters 12 h after each dose.

SETTING

Large teaching hospital, primary referral centre.

PATIENTS

Six patients (four women; age range 37-78 years) with pulmonary hypertension (one with primary pulmonary hypertension, five with thromboembolic disease.

MAIN OUTCOME MEASURES

Mean pulmonary artery pressure and pulmonary vascular resistance decreased by greater than 20% in two patients, mean pulmonary artery pressure decreased by greater than 20% in one patient with a pulmonary vascular resistance reduction of 19%. Thus, two of six patients responded to amlodipine and one partially responded.

RESULTS

The whole group mean (SEM) pulmonary artery pressure decreased from 47.7 (4.2) to 41.7 (4.4) mm Hg and mean pulmonary vascular resistance from 8.6 (2.1) to 7.1 (1.8) Wood units. Cardiac output rose by a mean (range) of 4% (-20.8 to+20.8), heart rate by 8.8% (-10 to +33), and systemic systolic blood pressure decreased by 12% (-29.2 to -5.8) and diastolic blood pressure by 6.8% (-28.2 to+20.0). There were no symptoms of systemic hypotension.

CONCLUSION

These results show that oral amlodipine can produce acute pulmonary vasodilatation in patients with pulmonary hypertension. Further studies are required, but amlodipine may prove to be of value in the treatment of primary pulmonary hypertension.

Unexpected lethal pulmonary hypertension in a 5-year-old girl successfully treated for biliary atresia

There appears to be a relationship between portal and pulmonary hypertension. A 5-year-old girl treated for biliary atresia developed this combination unexpectedly and died of pulmonary hypertension. Established pulmonary hypertension has a poor prognosis, which underscores the importance of early diagnosis by regular screening.

Primary pulmonary hypertension in children: clinical characterization and survival

OBJECTIVES

This study characterized mortality in a group of Mexican children (n = 18, mean [+/- SD] age 9.9 +/- 3 years) with primary pulmonary hypertension and investigated the factors associated with their survival.

BACKGROUND

Primary pulmonary hypertension is a progressive, fatal disease of unknown cause. Establishing the diagnosis earlier in life may influence prognosis.

METHODS

A dynamic cohort of children with primary pulmonary hypertension were enrolled between December 1977 and May 1991 and followed up through September 1992. Measurements included hemodynamic and pulmonary function variables in addition to demographic data, medical history and response to vasodilator treatment. We also compared the survival estimates of these children with those of our adult patients with primary pulmonary hypertension (n = 42, mean age 27.9 +/- 8.5 years).

RESULTS

Baseline mean (+/- SD) pulmonary artery pressure was similar in children and adults (66 +/- 15 vs. 65 +/- 18 mm Hg, p = NS), but a higher cardiac index resulted in a lower mean pulmonary vascular resistance index in children (18 +/- 7 vs. 26 +/- 12 U/m2, p < 0.01). The proportion of patients who had a positive hemodynamic response to vasodilator treatment was higher in children than in adults (41% vs. 25%). Estimated median survival in children was 4.12 years (95% confidence interval [CI] 0.75 to 8.66) and 3.12 years in adults (95% CI 0.5 to 13.25, chi-square log-rank 0.81, p = NS). Elevated right atrial pressure (rate ratio 10.2) and decreased stroke volume index (rate ratio 32.9) were the only significant predictors of mortality (Cox proportional hazards model).

CONCLUSIONS

Children with primary pulmonary hypertension have a poor survival expectancy, which does not appear to differ from that in adults with primary pulmonary hypertension. Mortality in childhood primary pulmonary hypertension is also associated with variables that assess right ventricular dysfunction.

Long-term iloprost infusion therapy for severe pulmonary hypertension in patients with connective tissue diseases

OBJECTIVE

To determine the effects of short-term, maximum-tolerated-dose and long-term, optimum-dose iloprost treatment of severe pulmonary hypertension associated with systemic sclerosis (SSc) and the primary antiphospholipid syndrome (APS).

METHODS

Three patients with SSc and 2 with APS who had failed to respond to oral vasodilator therapy for pulmonary hypertension were enrolled in a 32-week, open, prospective trial. Short-term infusion of maximum-tolerated doses and continuous infusion of optimum doses of iloprost were carried out following baseline cardiac catheterization. Catheterization was repeated at 2 and 32 weeks. All 5 patients completed the study and continued therapy for an average of 82 weeks (range 58-103).

RESULTS

Acute infusion of maximum tolerated doses significantly ameliorated the cardiac index (0.92 liters/minute/m2; P < 0.01), pulmonary artery O2 saturation (10.6%; P < 0.05), and pulmonary resistance (-6.7 units; P < 0.05). After 2 weeks of continuous infusion of optimum doses, there was improvement in pulmonary resistance (> or = 16%) and pulmonary artery O2 saturation (> 30%) in the 2 patients with primary APS. After 2 and 32 weeks, the 3 SSc patients showed variable hemodynamic responses. New York Heart Association functional class and exercise tolerance improved in all patients. There was 1 episode of bacteremia, and 1 patient died after 72 weeks of study.

CONCLUSION

Continuous iloprost infusion may improve exercise tolerance and quality of life in patients with severe pulmonary hypertension associated with SSc and primary APS.

Pharmacotherapy of chronic pulmonary arterial hypertension: value and limitations. Part I: Primary pulmonary hypertension

Efforts aimed at assessing pharmacotherapy of pulmonary arterial hypertension (PHT) have largely focused on patients with primary PHT, PHT associated with selected connective tissue diseases, and various forms of hypoxic secondary PHT. Part I of this review discusses the value and limitations of a wide variety of vasodilator drugs, oxygen, and warfarin in the treatment of primary PHT with special reference to their effects on pulmonary and systemic hemodynamics, functional capacity, and survival.

Survival in primary pulmonary hypertension. Validation of a prognostic equation

BACKGROUND

The prognosis of patients with primary pulmonary hypertension (PPH) remains a major problem for the planning and assessment of therapeutic interventions. The objectives of this study were (1) to characterize mortality in a Mexican population of patients with PPH and to investigate factors associated with survival and (2) to test the applicability in this population of the prognostic equation proposed by the US National Institutes of Health study on PPH.

METHODS AND RESULTS

A dynamic cohort of patients with PPH at our institution were enrolled between June 1977 and August 1991 and prospectively followed at regular intervals through September 1992. Measurements at diagnosis included hemodynamic and pulmonary function variables in addition to information on demographic data and medical history. The response to vasodilator treatment was also analyzed. The estimated median survival of the group was 4.04 years (95% confidence interval, 2.98 to 5.08 years). Variables associated with poor survival (univariate analysis) included an elevated mean right atrial pressure, a decreased cardiac index, and a decreased mixed venous PO2. A reduced forced vital capacity and the absence of vasodilator treatment were also associated with poor survival. A multivariate Cox proportional-hazards regression analysis was used to assess the adjusted hazard ratios, hence the relative contributions of the variables controlling for confounding. Reduced forced vital capacity and cardiac index and increased right atrial pressure were still significantly associated as risk factors for survival in patients with PPH. Survival as computed by the equation correlated with real survival of PPH patients with positive predictive values of 87%, 91%, and 89% at 1, 2, and 3 years, respectively. The equation, however, was relatively unable to predict deaths in our population, in part because of the strict limits of poor prognosis.

CONCLUSIONS

Mortality in PPH is largely associated with hemodynamic variables that assess right ventricular function. The proposed prognostic equation had a high sensitivity and a relatively low specificity to predict survival in our PPH population. To improve this specificity it may be necessary to increase the limits of poor prognosis as defined by the equation.

Prostacyclin (epoprostenol) and heart-lung transplantation as treatments for severe pulmonary hypertension

OBJECTIVE

To determine whether epoprostenol (prostacyclin, PGI2) or heart-lung transplantation (HLT), or both improves survival of patients with severe pulmonary hypertension.

DESIGN

This was a prospective study where the effects of epoprostenol were compared with conventional treatment. Also, the benefits of epoprostenol and HLT were assessed by comparing survival in this group with that of 120 patients at the Mayo Clinic before HLT and epoprostenol treatment became available.

PATIENTS AND INTERVENTIONS

Forty four patients were studied; 25 received continuous epoprostenol over a four year period (mean (SD) cardiac index 1.8 (0.4) 1 min-1 m-2 and mean (SD) pulmonary artery pressure (PAP) 70 (16) mm Hg) and 19 did not (cardiac index 2.1 (0.6) 1 min-1 m-2 and PAP 64 (13) mm Hg). Ten patients underwent HLT: seven had received epoprostenol, and three had not.

RESULTS

The therapeutic intervention with epoprostenol, or HLT, or both improved survival compared with the Mayo clinic patients (p = 0.05). Most of the benefit was conferred by epoprostenol, which prolonged survival twofold from a median time of eight to 17 months and doubled the changes of successful HLT. The improved survival with epoprostenol was not related to its immediate capacity to cause pulmonary vasodilation. Those patients who had limited acute pulmonary vasodilation when treated with epoprostenol showed the greatest improvement in survival.

CONCLUSIONS

These preliminary results indicate that those pulmonary hypertensive patients with the poorest chance of survival can be helped by epoprostenol and by HLT.

Autoantibodies in patients with primary pulmonary hypertension: association with anti-Ku

PURPOSE

Patients with primary pulmonary hypertension (PPH) frequently have Raynaud's phenomenon, serum antinuclear antibodies (ANAs), and/or pulmonary vascular lesions similar to those seen in certain connective tissue diseases, especially scleroderma. A number of relatively disease-specific autoantibodies have been described in connective tissue diseases but have not been studied in patients with PPH. Therefore, sera from PPH patients were studied for a variety of autoantibodies, seeking a possible link between this pulmonary disorder and connective tissue diseases.

PATIENTS AND METHODS

Sera from 31 patients with PPH and 24 with secondary pulmonary hypertension (SPH) were studied for the following autoantibodies: anti-centromere (indirect immunofluorescence of Hep-2 cells), anti-CENP-B by immunoblotting and enzyme immunoassay (EIA) using cloned CENP-B fusion protein, anti-topoisomerase I (Scl-70), anti-Ku using immunoblotting of affinity purified antigens, anti-cardiolipin using EIA, and anti-Ro (SS-A), La (SS-B), Sm, nRNP, Jo-1, PM-Scl, and Mi-2 by counter-current immunoelectrophoresis.

RESULTS

Anti-Ku antibodies were found in 23% of patients with PPH, 4% with SPH, and none of 24 normal controls (PPH versus SPH, p = 0.06: PPH versus controls, p = 0.01). Antibodies to CENP-B were found in one patient each with PPH and SPH, anti-topoisomerase I in one with SPH, and anti-Ro (SS-A) and La (SS-B) in one with PPH. Overall, 12 patients (39%) with PPH had Raynaud's phenomenon or positive ANA results, with 9 (29%) having more specific autoantibodies associated with connective tissue diseases.

CONCLUSIONS

These results further suggest a link between at least a subgroup of patients with PPH and autoimmune connective tissue diseases, with anti-Ku antibodies being a possible new serologic marker.

The effect of high doses of calcium-channel blockers on survival in primary pulmonary hypertension

BACKGROUND

Primary pulmonary hypertension is a progressive, fatal disease of unknown cause. Vasodilator drugs have been used as a treatment, but their efficacy is uncertain.

METHODS

We treated 64 patients with primary pulmonary hypertension with high doses of calcium-channel blockers. Patients who responded to treatment (defined as those whose pulmonary-artery pressure and pulmonary vascular resistance immediately fell by more than 20 percent after challenge) were treated for up to five years. Their survival was compared with that of the patients who did not respond and with patients enrolled in the National Institutes of Health (NIH) Registry on Primary Pulmonary Hypertension. Warfarin was given to 55 percent of the patients as concurrent therapy, on the basis of a lung scan showing nonuniformity of pulmonary blood flow (47 percent of patients who responded and 57 percent of those who did not respond).

RESULTS

Seventeen patients (26 percent) responded to treatment, as indicated by a 39 percent fall in pulmonary-artery pressure and a 53 percent fall in the pulmonary-vascular-resistance index (P less than 0.001). Nifedipine (mean [+/- SD] daily dose, 172 +/- 41 mg) was given to 13 patients, and diltiazem (mean daily dose, 720 +/- 208 mg) was given to 4 patients. After five years, 94 percent of the patients who responded (16 of 17) were alive, as compared with 55 percent of the patients who did not respond (26 of 47, P = 0.003). The survival of the patients who responded was also significantly better than that of the NIH registry cohort (P = 0.002) and patients from the NIH registry who were treated at the University of Illinois (P = 0.001). The use of warfarin was associated with improved survival (P = 0.025), particularly in the patients who did not respond.

CONCLUSIONS

This study suggests that high doses of calcium-channel blockers in patients with primary pulmonary hypertension who respond with reductions in pulmonary-artery pressure and pulmonary vascular resistance may improve survival over a five-year period.

Primary idiopathic pulmonary hypertension complicated by pulmonary arterial thrombosis. Association with antiphospholipid antibodies

OBJECTIVE

We report an unusual case of primary pulmonary hypertension and review the pertinent literature.

METHODS

A 25-year-old Caucasian woman presented with progressive dyspnea and was found to have pulmonary hypertension. Antiphospholipid antibodies were present. The patient had a prolonged hospital course, was unresponsive to therapy, and died suddenly.

RESULTS

Postmortem examination revealed a large thrombus affecting the right main pulmonary artery, with plexogenic arteriopathy bilaterally.

CONCLUSION

This appears to be the first reported case of primary pulmonary hypertension complicated by thrombosis of a main pulmonary artery in association with antiphospholipid antibodies.

Thoracic epidural anaesthesia and primary pulmonary hypertension

Patients with primary pulmonary hypertension occasionally present for surgery. Anaesthesia requires continuous cardiovascular monitoring and maintenance of stable pulmonary and systemic haemodynamics. The management of a patient with severe pulmonary hypertension, undergoing open lung biopsy under a combination of general anaesthesia and thoracic epidural analgesia is reported and the problems of primary pulmonary hypertension are discussed.

Primary pulmonary hypertension and functional hyposplenism

Primary pulmonary hypertension is a rare disease of unknown case. Functional hyposplenism is characterized by the appearance of abnormal circulating erythrocytes despite the presence of a spleen and is associated with a variety of disease states. A case of primary pulmonary hypertension associated with functional hyposplenism is described in this report.

Hemodynamic correlates of exercise function in patients with primary pulmonary hypertension

The purpose of this investigation was to study the hemodynamic correlates of exercise function in patients with primary pulmonary hypertension and to further define the role of exercise testing in the evaluation of these individuals. Data from the progressive exercise tests and subsequent cardiac catheterization in 16 consecutive patients, aged 16.9 +/- 10.4 years (range 6 to 35), with primary pulmonary hypertension were prospectively collected and analyzed. Exercise capacity averaged 40 +/- 36% (range 0 to 117%) of that predicted for age, height and gender. Statistically significant correlations existed between exercise capacity and 10 invasively measured hemodynamic variables. Mean right atrial pressure, a variable previously noted to be one of the best predictors of survival in patients with primary pulmonary hypertension, correlated best with exercise capacity (r = -0.83, p less than 0.0001). Exercise capacity greater than 75% of the predicted value identified the two patients who had a positive response to acute pulmonary vasodilator drug testing. Poor exercise capacity (less than 10% of the predicted value) identified the three patients who died during or soon after cardiac catheterization. The ability of exercise testing to identify patients at high risk for cardiac catheterization was superior to that of other noninvasive variables. Results of exercise testing may help guide decisions regarding the optimal timing of heart-lung or single lung transplantation.

Primary pulmonary hypertension. Vascular structure, morphometry, and responsiveness to vasodilator agents

The use of pharmacologic agents in the treatment of pulmonary hypertension has not proved to be uniformly successful or predictable. One possible reason for the vagaries in response is that the pulmonary vascular lesions are not consistent. We examined the relation between the structure of the pulmonary resistance vessels in unexplained (primary) pulmonary hypertension and the response to pulmonary vasodilators. Our study involved 19 patients with clinically unexplained pulmonary hypertension (mean pressure, 59 +/- 14 mm Hg). After characterizing them clinically and performing control hemodynamic measurements, we determined the acute effects of a series of vasodilator agents that have different mechanisms of action. In 16 patients, lung biopsy material was related to the hemodynamic studies; in nine patients, including six who had undergone open lung biopsy, the hemodynamic studies were related to the pathologic changes found at autopsy. Histologic specimens from all 19 patients were evaluated qualitatively and sorted into three subsets of hypertensive pulmonary arteriopathy: medial hypertrophy (with minimal intimal proliferation), arteriopathy with plexiform lesions (associated predominantly with concentric laminar intimal proliferation and fibrosis), and arteriopathy with microthrombotic lesions (associated predominantly with eccentric intimal proliferation and fibrosis). The 16 lung biopsies were also quantitated by morphometric techniques. Using a decrease in calculated pulmonary vascular resistance of more than 30% accompanied by a decrease in mean pulmonary arterial pressure of at least 10% to define vasodilation, only four patients were responders. The patients varied considerably in their responses to different vasodilator agents. Patients with similar clinical and hemodynamic profiles differed considerably with respect to the nature of their pulmonary vascular obstructive lesions and their responses to vasodilator agents. Qualitative histologic examination of lung tissue did not provide a basis for predicting how individual patients would respond to vasodilator agents. However, quantitative morphologic analysis of the initial open lung biopsy specimens did prove helpful in predicting acute responsiveness to vasodilator agents and the subsequent clinical course of these patients with unexplained (primary) pulmonary hypertension. An intimal area of more than 18% of the vascular cross-sectional area had an 85% predictive value for identifying the patients who did poorly during the first 36 months of follow-up.

Pulmonary capillary hemangiomatosis. A report of three cases and a review of the literature

Pulmonary capillary hemangiomatosis (PCH) is a rare cause of pulmonary hypertension. At present, only eleven cases have been reported. This report describes the clinical and pathologic findings in three additional cases who presented to the University of Pittsburgh for heart-lung transplantation and integrates the clinical features of all fourteen cases. Clinically, this disorder should be suspected in a patient who presents with pulmonary hypertension, hemoptysis, a reticulonodular infiltrate on chest radiograph, a lung scan showing inhomogeneously enhanced perfusion (particularly in the lower lobes), and pulmonary angiography showing increased peripheral vascularity corresponding to both the radiographic infiltrate and the areas of enhanced perfusion on lung scan. Histologic features consist of nodular proliferation of capillary-sized vessels that infiltrate the pulmonary interstitium, vascular walls, and lumens as well as the alveolar septa. The vascular invasion results in a secondary veno-occlusive phenomenon that explains the clinical confusion with pulmonary veno-occlusive disease.

Doppler echocardiography and ultrafast cine computed tomography during dynamic exercise in chronic parenchymal pulmonary disease

In an effort to better understand the cardiac contribution to exercise limitation in chronic lung disease, 21 patients with advanced chronic pulmonary parenchymal disease and 10 normal control subjects were evaluated for changes in right ventricular (RV) pressure, volume and function during incremental, symptom-limited supine bicycle exercise. Patients underwent sequential exercise tests with Doppler echocardiography and ultrafast cine computed tomography (CT). RV systolic pressure during exercise was determined by saline-enhanced Doppler of tricuspid regurgitation. RV ejection fraction, end-diastolic volume, stroke volume and cardiac index were obtained by CT at rest and peak exercise. Sixteen of the 21 study patients also exercised on high-flow oxygen. In the control subjects RV systolic pressure increased from 21 +/- 6 mm Hg (mean +/- standard deviation) at rest to 32 +/- 8 mm Hg at peak exercise, whereas in patients with lung disease, RV systolic pressure increased from 42 +/- 17 to 81 +/- 26 mm Hg (both p less than 0.01). Compared with the control subjects, the patients with lung disease had significantly lower mean values for RV ejection fraction at rest (47 +/- 7 vs 55 +/- 7%) and at peak exercise (47 +/- 9 vs 57 +/- 3%, respectively, both p less than 0.05). The patients who demonstrated oxyhemoglobin desaturation during exercise showed the most abnormal cardiac responses, with marked increases in mean RV systolic pressure, decreases in mean RV ejection fraction and blunted increases in cardiac index and RV stroke volume. Although acute oxygen supplementation was associated with a slight decrease in RV systolic pressure at peak exercise and a longer duration of exercise, there was no significant improvement in RV function. Doppler echocardiography and CT provide complementary and potentially useful information about right-sided heart pressures and RV ejection fraction during exercise in patients with advanced chronic lung disease. Oxyhemoglobin desaturation during exercise is a marker for the most abnormal pulmonary vascular reserve, as indicated by RV contractile dysfunction and limited ability to increase cardiac index.

Two-dimensional and Doppler-echocardiographic and cardiac catheterization correlates of survival in primary pulmonary hypertension

To determine correlates of survival in primary pulmonary hypertension, we compared 41 echocardiography-Doppler and nine catheterization parameters with outcome in 26 patients. Mean follow-up was 19.7 months in survivors; mean survival was 4.8 months in 16 nonsurvivors. Cox life-table univariate analysis correlated two echocardiographic, three Doppler, and three catheterization variables with poor survival (p less than or equal to 0.05), and chi 2 analysis ensured the best critical values: severity of pericardial effusion, heart rate of more than 87 beats/min, pulmonic flow acceleration time of less than 62 msec, tricuspid early flow deceleration (T-DEC) equal to or less than -300 cm2/sec, mitral early flow-to-atrial flow velocity ratio (M-E/A) equal to or less than 1.0, catheterization cardiac index (CI) equal to or less than 2.3 l/min/m2, mean pulmonary artery pressure of more than 61 mm Hg, and diastolic pulmonary artery pressure of more than 43 mm Hg. Multivariate life-table analysis of noninvasive variables revealed the severity of pericardial effusion to be independently significant (p = 0.006), whereas analysis of catheterization variables revealed cardiac index to be independently significant (p = 0.014). Combined multivariate analysis did not differ from the noninvasive results alone. Categorical modeling of the eight significant variables split at their critical values (present or absent) revealed M-E/A, T-DEC, and CI to be independently significant by multivariate analysis (p = 0.0014). Analysis of the five echocardiography-Doppler variables alone revealed M-E/A, T-DEC, and heart rate to be independently significant (p = 0.0016). In both cases, mortality increased with the number of critical values reached.(ABSTRACT TRUNCATED AT 250 WORDS)

Electrocardiographic and hemodynamic correlations in primary pulmonary hypertension

In order to evaluate the pulmonary hemodynamics in primary pulmonary hypertension, the relation between the standard 12-lead electrocardiogram (ECG) and pulmonary hemodynamics as determined by right-heart catheterization was analyzed. Significant positive correlations were noted between amplitude of the R in V1, the R/S ratio in V1, and the pulmonary artery systolic pressure (r = 0.46 and 0.50, respectively, p less than 0.01). An amplitude of the R in V1 of more than 1.2 mV indicated a pulmonary artery systolic pressure of more than 90 mmHg with a sensitivity of 94% and a specificity of 47%. The cardiac index showed a significant positive relationship with amplitude of the R in V5 and V6 and the R/S ratio in V5 and V6 (r = 0.46, 0.46, 0.39, and 0.48, respectively; each with a p less than 0.01). Moreover, an AQRS greater than or equal to 100 degrees, and either an SV6 greater than or equal to 0.7 mV, or R/SV6 less than or equal to 2 indicated a cardiac index of less than 2.8L/min/m2 with a sensitivity of 82% and 84% and a specificity of 86% and 100% respectively. This study suggests, therefore, that the 12-lead ECG is useful for the evaluation of the severity of pulmonary hypertension by its ability to predict pulmonary artery systolic pressure and cardiac index with clinically useful accuracy.

[Pulmonary arterial hypertension and systemic lupus erythematosus. Apropos of 2 cases. Review of the literature]

Pulmonary arterial hypertension may develop in patients with systemic lupus erythematosus (SLE) in the absence of lung tissue lesion or embolism in the pulmonary circulation. Its mechanisms and prognosis are imperfectly known, although various suggestions have been made concerning the possible role of pulmonary arterial spasm, immune complex arteritis or arterial wall fibrosis. We report two cases of SLE in female patients who presented with clinical signs of pulmonary arterial hypertension. The fact that pulmonary arterial hypertension regressed completely in one patient and resulted in death in the other points to different pathogenic mechanisms. In the first patient the dramatic therapeutic effectiveness of a calcium inhibitor suggests that an arterial spasm was involved, whereas the anatomical lesions found in the second patient are in favour of a fibrotic inflammatory arteritis. This pathogenic heterogeneity of pulmonary arterial hypertension in SLE, which may correspond to different evolutive stages of the disease, is documented by a review of the literature with special attention to the frequency and to the clinical biochemical, haemodynamic and histological aspects of this complication of SLE.

Prostaglandin E1 as a screening vasodilator in primary pulmonary hypertension

Pulmonary vasodilators are variably efficacious in primary pulmonary hypertension (PPH). None has consistently improved hemodynamics enough to obviate the need for complex and potentially hazardous testing of several vasodilators. Prostaglandin E1 (PGE1), a potent, short-acting pulmonary vasodilator, was administered to seven patients with PPH in order to determine whether PGE1 could accurately predict the hemodynamic and gas exchange effects of other commonly used vasodilators. Prostaglandin E1, nifedipine and hydralazine were administered to the patients while measuring pulmonary and systemic hemodynamics and arterial blood gases. Prostaglandin E1 was easily titrated but was inconsistent as a predictor of the effects of the other vasodilators with respect to pulmonary artery pressure, cardiac output and adverse effects on arterial oxygenation. This study suggests that patients with PPH must still receive carefully monitored trials of several vasodilators to determine whether there is a beneficial response and to select the appropriate treatment.

Natural history of pulmonary hemodynamics in primary pulmonary hypertension

To study the relationship between the hemodynamic characteristics and prognosis in PPH, we analyzed the data on patients whose prognosis was well documented from the time of hemodynamic monitoring. Our subjects were 87 patients obtained from a nationwide survey in Japan. PCWPs were obtained in 44 patients and COs were measured in 59 patients. The average age was 33 years (range 14 to 69). Patients were followed prospectively for up to 100 months and were categorized based on the survival period from the time of catheterization. Hemodynamic variables that showed significant differences or prognostic trends were RVedp, pulmonary artery diastolic pressure, PCWP, CI, PVR, and PVR/SVR ratio. The CI correlated with the number of survival months (r = 0.583; p less than 0.01). The hemodynamic state of patients who died suddenly within 1 year from the time of catheterization was no different from those who died of clinical right-sided heart failure. The partial pressure of oxygen of arterial blood was the only variable discriminating sudden deaths from right-sided heart failure deaths (54 +/- 2 vs 66 +/- 4 mm Hg; p less than 0.05). The results of this study indicate that the major determinant of prognosis is right ventricular function and that the CI might be used as a prognostic indicator. In addition, sudden death is more likely to occur in patients with severe hypoxia.

Primary pulmonary hypertension. Length of survival in patients referred for heart-lung transplantation

The paucity of data on the natural history of primary pulmonary hypertension (PPH), and the observation that some patients awaiting heart-lung transplantation (HLT) appeared to be living longer than expected, led us to analyze the survival data of patients with PPH who had been referred for consideration of HLT. Ninety patients (female: male = 3.6:1) met clinical and hemodynamic criteria for PPH. Age at diagnosis was 29.8 +/- 7.9 years (mean +/- SD) (range 13-48 years). Symptom duration was 65.9 +/- 47.4 months, while survival from diagnosis was 42.9 +/- 42.6 months, giving a mean lead time of 23 months. Mean pulmonary artery pressure (PAP) at diagnosis was 61.6 +/- 15.0 mm Hg. The incidence of patent foramen ovale (PFO) was 19 percent, postpartum onset 16 percent, family history 6 percent, and cirrhosis 3 percent. The survival of 27 patients who died without operation was 50.3 +/- 52.5 months (median 37 months), with a symptom duration of 68.4 +/- 57.5 months (median 64 months). Both a high mean right atrial pressure (RAP) (p less than 0.025) and high mean PAP (p less than 0.025) correlated inversely with survival. For the whole group, none of the variables, age at diagnosis, sex, mean PAP or mean RAP at diagnosis, symptom duration prior to diagnosis or the presence of a PFO, postpartum onset or positive family history, significantly influenced survival. However, a low cardiac output (p less than 0.05) adversely influenced prognosis. The discrepancy between the mean and median length of survival in our group and previous reports confirms the need for further clarification of natural history and for appropriate clinical trials to assess therapeutic endeavors.