Long-term outcomes in acute pulmonary thromboembolism: the incidence of chronic thromboembolic pulmonary hypertension and associated risk factors

The long-term outcomes of pulmonary thromboembolism (PTE) and/or incidence of chronic thromboembolic pulmonary hypertension (CTEPH) are not well documented. Three hundred twenty-five consecutive cases objectively diagnosed with PTE monitored for an average 16.3 months (6-50.7 months) were investigated. Data concerning recurrence, residual thrombus, mortality, and CTEPH in particular were collected. Chronic thromboembolic pulmonary hypertension frequency acute first episode of PTE was 4.6%. Chronic thromboembolic pulmonary hypertension developed within 12 months after PTE attack in approximately 80% of patients and it did not occur after 2 years. Residual chronic thrombus was determined at the 3rd month in 48% of cases post-PTE, at the 6th month in 27.4%, and at the 12th month in 18.2%. At multivariate regression analysis, systolic pulmonary arterial pressure > 50 mm Hg, hazard ratio: 10.1 (95% confidence interval: 4.1-71.2) were predictors of CTEPH. Chronic thromboembolic pulmonary hypertension develops as a serious complication in a significant number of cases with PTE. Closer monitoring of high-risk cases in particular is important in terms of early diagnosis and treatment.     

肺动脉血栓内膜剥脱术治疗慢性栓塞性肺动脉高压效果分析

目的分析慢性栓塞性肺动脉高压(CTEPH)患者应用肺动脉血栓内膜剥脱术(PTE)治疗的围手术期及中、晚期效果。方法选择CTEPH患者81例,按临床病理分型分为中央型组60例和外周型组21例,在深低温停循环下行PTE,随访5年,观察生存率。回顾性按年龄将患者分为老年组(≥60岁,19例)和非老年组(<60岁,62例),比较2组早期及晚期生存率。结果中央型组围手术期死亡1例。外周型组患者体外循环时间、主动脉阻断时间、深低温停循环时间均显著长于中央型组;围手术期肺动脉高压危象发生率显著高于中央型组,肺再灌注损伤发生率显著低于中央型组;肺动脉收缩压、肺循环阻力显著高于中央型组(P<0.05,P<0.01)。随访期间1例死亡,5年生存率为98.77%。老年组与非老年组术后早期及晚期生存率差异无统计学意义(P>0.05)。结论 PTE治疗CTEPH患者有较好的围手术期及中、晚期生存率,老年患者术后早期及晚期生存率与非老年患者无显著差异。术前准确评估,可提高PTE早期及中、晚期生存率。     

Prognostic significance of early diagnosis in acute pulmonary thromboembolism with circulatory failure

Despite the advances in our understanding of venous thromboembolic disease, the prevalence of pulmonary thromboembolism (PTE) at autopsy has not changed over 3 decades. When patients survive long enough to have a diagnosis of massive PTE and start receiving treatment, the outlook is considered to be moderately good. However, the diagnosis is often difficult to obtain and is frequently missed. We hypothesize that mortality of acute PTE is reduced by early diagnosis. Eighty-five patients with acute PTE with circulatory failure who survived 1 h after the onset were divided into two groups: the early Dx group consisted of the patients whose disease was diagnosed as acute PTE within 24 h of the onset, and the Late Dx group included patients whose disease was not diagnosed within 24 h of onset, or died without clinical diagnosis between 1 and 24 h after the onset. Overall mortality was significantly low in the Early Dx group compared with that of the Late Dx group (21.6% vs 67.6%, P < 0.0001). Multiple logistic regression analysis demonstrated that a reduction in in-hospital mortality was associated with early diagnosis (odds ratio for in-hospital death, 0.094; 95% confidence interval, 0.03–0.33). The results of our study suggested that early diagnosis might favorably affect the in-hospital clinical outcome of hemodynamically unstable patients with acute PTE. Received: March 14, 2002 / Accepted: June 21, 2002 Correspondence to M. Nakamura     

Cytokine response to pulmonary thromboendarterectomy

BACKGROUND: Pulmonary thromboendarterectomy (PTE) is an effective but challenging treatment for chronic thromboembolic pulmonary hypertension (CTEPH). PTE is associated with marked hemodynamic instability in the perioperative course, suggesting the involvement of circulating mediators. The aim of this study was to characterize the expression of proinflammatory and anti-inflammatory cytokines in patients undergoing PTE. METHODS: Fourteen patients with CTEPH (mean [+/- SD] pulmonary vascular resistance, 1,056 +/- 399 dyne.s.cm(-5)) underwent PTE using cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest (DHCA). Peripheral arterial blood samples were drawn prior to patients undergoing sternotomy, during CPB, before and after DHCA, and 0, 8, 16, 24, and 48 h after surgery. An enzyme-linked-immunosorbent assay was used to analyze the plasma levels of tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and IL-10. Seven patients undergoing aortic arch replacement (ARCH) in DHCA served as a control group. RESULTS: Prior to and during PTE, the CTEPH patients exhibited elevated TNF-alpha levels, which decreased within the first 24 postoperative hours (p = 0.02). There was no TNF-alpha release among patients in the ARCH group. IL-6 levels were similar in both groups throughout the perioperative course. A profound anti-inflammatory response was observed in the PTE group, which was reflected by elevated IL-10 levels prior to surgery and a marked peak level immediately after surgery. A positive correlation was found between maximum vasopressor support and peak levels of IL-6 (r = 0.82) in the PTE patients. CONCLUSION: Heart failure due to CTEPH appears to generate a pronounced inflammatory response with the release of proinflammatory and anti-inflammatory cytokines. PTE results in the rapid normalization of preoperatively elevated TNF-alpha levels. IL-6-mediated systemic inflammatory cascades may be involved in the regulation of peripheral vascular tone after PTE.     

肺动脉血栓内膜剥脱术的远期疗效

目的　观察肺动脉血栓内膜剥脱术 (PTE)对慢性栓塞性肺动脉高压 (CTEPH )患者的远期疗效。方法　 1997年 3月～ 2 0 0 2年 6月 ,共对 15例CTEPH患者行PTE ,14例存活出院。其中 13例随访时间平均 4 0 (17～ 77)个月 ,1例失访 ;随访项目包括心功能状态、血气分析和通过超声心动图测量肺动脉收缩压。结果　随访期内 13例患者均存活 ,其术前心功能NYHA分级均为Ⅲ、Ⅳ级 ;术后 12例患者心功能NYHA分级Ⅰ级、1例Ⅲ级 ;动脉血氧分压 (PaO2 )由术前的 (5 8 1± 8 6 )mmHg上升至(90 8± 6 0 )mmHg (P <0 0 1) ;动脉血氧饱和度由术前的 (90± 5 ) %上升至 (96± 1) % (P <0 0 5 ) ;肺动脉收缩压由术前的 (97 1± 2 2 4 )mmHg下降至 (4 2 6± 10 7)mmHg (P <0 0 1)。结论　肺动脉血栓内膜剥脱术对慢性栓塞性肺动脉高压患者具有很好的远期疗效 ,它能显著改善患者的心肺功能 ,提高其生活质量     

Incidence and risk factors of chronic thromboembolic pulmonary hypertension in patients after acute pulmonary embolism

Background

Early identification and treatment of chronic thromboembolic pulmonary hypertension (CTEPH) are critical to prevent disease progression. We determined the incidence and risk factors for CTEPH in patients with a first episode of acute pulmonary embolism (PE).

Methods

In this study, consecutive patients with first-episode acute PE were followed for ≤5 years. Pulmonary hypertension (PH) was screened for by echocardiography. Suspected cases were evaluated by right heart catheterization (RHC) and pulmonary angiography (PA). If invasive procedures were not permitted, PH was diagnosed by systolic pulmonary artery pressure (SPAP) >50 mmHg. Diagnosis of CTEPH was confirmed by PA, ventilation/perfusion (V/Q) lung scan, or computed tomography (CT) PA (CTPA).

Results

Overall, 614 patients with acute PE were included (median follow-up, 3.3 years). Ten patients were diagnosed with CTEPH: cumulative incidence 0.8% [95% confidence interval (CI), 0.0-1.6%] at 1 year, 1.3% (95% CI, 0.3-2.3%) at 2 years, and 1.7% (95% CI, 0.7-2.7%) at 3 years. No cases of CTEPH developed after 3 years. History of lower-limb varicose veins [hazard ratio (HR), 4.3; 95% CI, 1.2-15.4; P=0.024], SPAP >50 mmHg at initial PE episode (HR, 23.5; 95% CI, 2.7-207.6; P=0.005), intermediate-risk PE (HR, 1.2; 95% CI, 1.0-1.4; P=0.030), and CT obstruction index over 30% at 3 months after acute PE (HR, 42.5; 95% CI, 4.4-409.8; P=0.001) were associated with increased risk of CTEPH.

Conclusions

CTEPH was not rare after acute PE in this Chinese population, especially within 3 years of diagnosis. Lower-limb varicose veins, intermediate-risk PE with elevated SPAP in the acute phase, and residual emboli during follow-up might increase the risk of CTEPH.     

210例入院诊断为慢性阻塞性肺疾病患者的PaO_2/PaCO_2分析

目的:分析入院第一诊断为慢性阻塞性肺疾病(COPD)患者的血气结果,探讨动脉血氧分压/动脉血二氧化碳分压(PaO2/PaCO2)比值在临床诊断与鉴别诊断中的价值。方法:回顾性分析了以第一诊断为COPD急性加重入院210例患者的临床资料,按出院第一诊断分为COPD急性加重组、肺血栓栓塞症(PTE)组、阻塞性睡眠呼吸暂停低通气综合征(OSAHS)组、哮喘组及间质性肺疾病组,将COPD急性加重组与其余4组患者吸氧前后的PaO2/PaCO2比值及PaCO2分别进行比较,观察2个指标在COPD急性加重组与其余4组间的差异是否有统计学意义。结果:1·210例中,出院第一诊断为COPD急性加重者154例(74%),PTE21例(10%)、OSAHS11例(5%)、哮喘15例(7%)、间质性肺疾病9例(4%),即:非COPD急性加重56例(26%)。2·COPD组与其他组比较显示:吸氧前及吸氧后,COPD组的PaO2/PaCO2比值明显低于PTE组与哮喘组,差异具有统计学意义;COPD组与间质性肺疾病组比较,PaCO2明显升高,有统计学意义。3·若取PaO2/PaCO2比值≤1·0同时PaCO2值≥45mmHg,则PTE组及哮喘组均为0例,即:可除外PTE及哮喘。结论:吸氧前后测定PaO2/PaCO2比值并联合PaCO2值对鉴别COPD与PTE、哮喘有一定的临床意义,但与OSAHS、间质性肺疾病的鉴别意义有限。PaO2/PaCO2比值计算方法简便,对临床有借鉴价值。     

慢性血栓栓塞性肺动脉高压的诊断和治疗体会

目的提高对慢性血栓栓塞性肺动脉高压(CTEPH)的认识和早期诊治水平。方法对我院1994年10月至2009年9月收治的104例CTEPH患者的临床资料进行回顾性分析。结果 CTEPH患者中男性多见,男:女为1.97:1,平均年龄46.4±16.7岁,病史37.0±19.6月。临床主要表现有活动性呼吸困难/气促、胸闷、胸痛及咯血等。所有患者超声心动图均示肺动脉高压,其他表现有右心室扩大、三尖瓣返流、主肺动脉内占位性病变等。而血管超声示下肢静脉血栓形成占68.3%。患者确诊均通过肺动脉造影(PPA,CTPA或MRPA)。入院时54例被误诊,误诊率为52%。41例给予内科治疗,63例行肺动脉血栓内膜剥脱术,死亡6例,总手术死亡率9.5%。57例成功手术者,肺动脉收缩压由术前93.2±35.8mmHg降至术后的51.2±14.1mmHg,动脉血氧分压由52.8±7.9mmHg升至86.4±9.2mmHg,二组前后相比有显著性差异(P0.05)。结论 CTEPH临床上比较少见,容易被误诊。UCG和CTPA有较大诊断价值。内科治疗效果欠佳,肺动脉血栓内膜剥脱术应作为首选治疗手段。     

Update on chronic thromboembolic pulmonary hypertension

Chronic, unresolved thromboemboli are an important cause of pulmonary hypertension (PH) with specific treatment strategies differing from other types of PH. Chronic thromboembolic pulmonary hypertension (CTEPH) is classified as group 4 PH by the World Health Organization. It is a rare, but underdiagnosed, complication of acute pulmonary embolism that does not resolve and results in occlusion of large pulmonary arteries with a fibro-thrombotic material. The etiology of CTEPH remains uncertain, and it is unknown why certain patients with acute pulmonary embolism develop this disorder. The evaluation for CTEPH is an important part of the evaluation for PH in general, and it is crucial not to overlook this diagnosis, as it is the only form of PH that is potentially curable. Patients diagnosed with CTEPH should be referred to an expert center for consideration of pulmonary endarterectomy, and surgical removal of the chronic thromboembolic material. Not all patients with CTEPH are surgical candidates, however, and there are emerging treatments—medical therapy and balloon pulmonary angioplasty—that have shown benefit in this patient population. Without treatment, CTEPH can lead to progressive pulmonary vascular obstruction, right heart failure, and death. Thus, it is important for clinicians to recognize this subtype of PH. In this review, we provide an overview of current understanding of the pathogenesis of CTEPH and highlight recommendations and recent advances in the evaluation and treatment of CTEPH.     

Chronic pulmonary embolism and pulmonary hypertension

Incomplete resolution of acute pulmonary embolism (PE) is frequently observed after acute PE and may rarely result in chronic thromboembolic pulmonary hypertension (CTEPH). The underlying pathophysiological mechanism is largely unknown. Evidence underlines the concept of a dual pulmonary vascular compartment model consisting of increased pulmonary vascular resistance by both large vessel obstruction and distal small vessel obliteration, the latter initiated by pathological vascular remodeling. Up to 40% of patients with established CTEPH have no prior history of symptomatic venous thromboembolism. CTEPH is associated with a poor prognosis if left untreated. Therefore, the diagnostic approach of CTEPH aims at assessing the location and extent of the embolic obstruction, establishing the operability and prognosis of the patients and ruling out other variations of pulmonary hypertension with distinct indicated treatment. Heart catheterization for invasive pressure measurements and pulmonary catheter angiography is obligatory for the final diagnosis. Pulmonary thromboendarterectomy is the treatment of choice. In certain patients with persistent or recurrent pulmonary hypertension after surgery or with inoperable disease, pharmacotherapy might be beneficial.     

Relationship between ECG findings and pulmonary artery pressure in patients with acute massive pulmonary thromboembolism.

Pulmonary thromboembolism (PTE) is associated with various electrocardiogram (ECG) abnormalities, but the utility of evaluating the severity of PTE based on ECG abnormalities alone has not been investigated in Japanese patients previously. The purpose of this study was to examine the relationship between ECG abnormalities and the mean pulmonary artery pressure (MPAP) in patients with acute massive PTE (AMPTE). ECG examination of 21 patients, who were diagnosed with AMPTE by pulmonary arteriography, found that S(1)Q(3)T (3) was the most frequently observed abnormality (in 67% of the patients), followed by negative T (62%), clockwise rotation (57%), and ST elevation (48%). When these patients were divided into 2 groups based on the level of MPAP, 8 of the 11 ECG findings, which were associated with PTE in a previous report, were more frequently observed in Group H (MPAP >/=40 mmHg) than in Group L (MPAP <40 mmHg). MPAP correlated significantly with the total number of ECG abnormalities (r=0.82, p<0.001). In particular, at least 5 ECG abnormalities were noted in patients with MPAP >/=45 mmHg. These results suggested that the total number of ECG abnormalities in patients with AMPTE can be used to evaluate the severity of APTE, including PAP level.     

Correlation of left ventricular diastolic filling characteristics with right ventricular overload and pulmonary artery pressure in chronic thromboembolic pulmonary hypertension

OBJECTIVES: This study was designed to determine a quantitative relationship between right ventricular (RV) pressure overload and left ventricular (LV) diastolic filling characteristics in patients with chronic thromboembolic pulmonary hypertension (CTEPH). BACKGROUND: Right ventricular pressure overload in patients with CTEPH causes abnormal LV diastolic filling. However, a quantitative relationship between RV pressure overload and LV diastolic function has not been established. METHODS: We analyzed pre- and postoperative diastolic mitral inflow velocities and right heart hemodynamic data in 39 consecutive patients with CTEPH over the age of 30 (55 +/- 11 years) with mean pulmonary artery pressure >30 mm Hg who underwent pulmonary thromboendarterectomy (PTE). RESULTS: After PTE, mean pulmonary artery pressure (mPAP) decreased from 50 +/- 11 to 28 +/- 9 mm Hg (p < 0.001) while cardiac output (CO) increased from 4.4 +/- 1.1 to 5.7 +/- 0.9 l/m (p < 0.001). Mitral E/A ratio (E/A) increased from 0.74 +/- 0.22 to 1.48 +/- 0.69 (p < 0.001). E/A was < 1.25 in all patients pre-PTE. After PTE, all patients with E/A >1.50 had mPAP <35 mm Hg and CO >5.0 l/min. E/A correlated inversely with mPAP (r = 0.55, p < 0.001) and directly with CO (r = 0.53, p < 0.001). CONCLUSIONS: E/A is consistently abnormal in patients with CTEPH and increases post-PTE. Moreover, E/A varies inversely with mPAP and directly with CO. Following PTE, E/A >1.5 correlates with the absence of severe pulmonary hypertension (mPAP >35 mm Hg) and the presence of normal cardiac output (> 5.0 l/m).     

Identification of chronic thromboembolic pulmonary hypertension on CTPAs performed for diagnosing acute pulmonary embolism depending on level of expertise

BackgroundExpert reading often reveals radiological signs of chronic thromboembolic pulmonary hypertension (CTEPH) or chronic PE on computed tomography pulmonary angiography (CTPA) performed at the time of acute pulmonary embolism (PE) presentation preceding CTEPH. Little is known about the accuracy and reproducibility of CTPA reading by radiologists in training in this setting.ObjectivesTo evaluate 1) whether signs of CTEPH or chronic PE are routinely reported on CTPA for suspected PE; and 2) whether CTEPH-non-expert readers achieve comparable predictive accuracy to CTEPH-expert radiologists after dedicated instruction.MethodsOriginal reports of CTPAs demonstrating acute PE in 50 patients whom ultimately developed CTEPH, and those of 50 PE who did not, were screened for documented signs of CTEPH. All scans were re-assessed by three CTEPH-expert readers and two CTEPH-non-expert readers (blinded and independently) for predefined signs and overall presence of CTEPH.ResultsSigns of chronic PE were mentioned in the original reports of 14/50 cases (28%), while CTEPH-expert radiologists had recognized 44/50 (88%). Using a standardized definition (≥3 predefined radiological signs), moderate-to-good agreement was reached between CTEPH-non-expert readers and the experts’ consensus (k-statistics 0.46; 0.61) at slightly lower sensitivities. The CTEPH-non-expert readers had moderate agreement on the presence of CTEPH (κ-statistic 0.38), but both correctly identified most cases (80% and 88%, respectively).ConclusionsConcomitant signs of CTEPH were poorly documented in daily practice, while most CTEPH patients were identified by CTEPH-non-expert readers after dedicated instruction. These findings underline the feasibility of achieving earlier CTEPH diagnosis by assessing CTPAs more attentively.     

肺血栓栓塞症十例临床病理分析

目的：为帮助临床进一步认识肺血栓栓塞症（PTE），对10例PTE进行临床病理分析。方法：收集近十年来的8例PTE尸检资料及2例外科肺血栓活检资料与临床进行对照分析。结果：10例PTE中，年龄3．5－72岁（平均33．3岁），来自先天性心脏病4例，心、肺恶性肿瘤各1例，风湿性心脏病1例，下肢静脉炎1例，另2例肺动脉血栓来源不明。10例中仅2例无心肺血管原发疾病，其临床PTE诊断与病理符合，余8例均未被临床诊断。结论：从本资料分析原有心血管病、心、肺肿瘤及合并肺炎（肺脓肿）患，其PTE常被临床漏、误诊。多争取病理检查，对临床医生进一步认识PTE会有帮助。     

慢性血栓栓塞性肺动脉高压诊疗的研究进展

慢性血栓栓塞性肺动脉高压(CTEPH)是急性肺栓塞最严重的并发症,由于缺乏特异性的临床表现,常常会漏诊,造成患者死亡。近年来,虽然多种影像技术已应用于CTEPH 患者,但在CTEPH 的诊断、预后及治疗的选择决策上仍有不确定性,熟练掌握各类影像技术特点,可提升利用率。目前肺动脉内膜剥脱术是治疗CTEPH 的首选方式,对于无法手术治疗的患者,经皮肺动脉成形术可作为一种新的治疗选择。本文主要综述了影像学检查在CTEPH 的诊断、治疗及预后评估中的研究进展。     

Pathophysiology of impaired right and left ventricular function in chronic embolic pulmonary hypertension: changes after pulmonary thromboendarterectomy

STUDY OBJECTIVES: This study sought to evaluate the pathophysiology of left and right heart failure in patients with chronic thromboembolic pulmonary hypertension (CTEPH) who were hospitalized to undergo pulmonary thromboendarterectomy (PTE). DESIGN: Thirty-nine patients (16 women and 23 men; mean +/- SD age, 55+/-12 years) with severe CTEPH were examined before and 13+/-8 days after PTE by way of transthoracic echocardiography and right heart catheterization. MEASUREMENTS AND RESULTS: Examination results confirmed in all cases that before surgery the right ventricles were enlarged and systolic function was impaired. Moderate to severe tricuspid valve regurgitation was observed. Left ventricular eccentricity indexes reflected a leftward displacement of the interventricular septum. End-diastolic left ventricular size and systolic function had decreased, and the left ventricular filling pattern showed impaired diastolic function. After surgery, mean pulmonary artery pressure was significantly lower (48+/- 10 mm Hg vs. 25+/-7 mm Hg; p<0.05). The calculated end-diastolic and end-systolic right ventricular areas had decreased: 30+/-7 cm(2) vs 21 +/-5 cm(2) (p<0.05) and 24+/-6 cm(2) vs. 14+/-4 cm(2) (p<0.05), respectively. Right ventricular fractional area change had increased (20+/-7% vs. 33+/-8%; p<0.05). Most of the patients exhibited a marked decrease in the severity of tricuspid regurgitation. Septal motion, left ventricular systolic function, and diastolic filling pattern returned to normal values (early to late diastolic left ventricular inflow ratio, 0.70+/-0.33 vs. 1.35+/-0.51; p<0.05). The mean cardiac index also improved (2.7+/-0.6 L/min/m(2) vs. 3.7+/-0.8 L/min/m(2)). CONCLUSIONS: In CTEPH, functions are impaired in the right as well as the left ventricles of the heart. Improved lung perfusion and the reduction of right ventricular pressure overload are direct results of PTE, which in turn bring a profound reduction of right ventricular size and a recovery of systolic function. Normalization of interventricular septal motion as well as improved venous return to the left atrium lead to a normalization of left ventricular diastolic and systolic function, and the cardiac index improves.     

修正Geneva量表及D-二聚体对慢性阻塞性肺疾病急性加重合并肺血栓栓塞症的预测价值

目的评价修正Geneva量表结合D-二聚体在诊断慢性阻塞性肺疾病急性加重期（AECOPD）合并肺血栓栓塞症（PTE）中的诊断价值。方法收集2011年1月至2013年5月于我院急诊及住院的AECOPD疑似合并PTE的210例患者进行前瞻性研究,对患者临床资料,并分别以修正Geneva量表、D-二聚体测定以及两者结合评估合并肺栓塞的可能性,并与最终确诊的诊断结果进行分析比较。结果其中41例患者确诊PTE。AECOPD＋PTE组与单纯AECOPD组在症状、体征上仅不对称下肢水肿有统计学差异。D-二聚体〈500μg／L的阴性预测值为96．1％,而阳性预测值仅34．3％,特异度58．0％灵敏度90．2％。修正Geneva量表可能性高组阳性预测值为64．0％,可能性低组阴性预测值为94．7％;两者结合的阳性预测率为42．5％,阴性预测值96．9％。结论修正Geneva量表和血浆D-二聚体测对慢性阻塞性肺疾病急性加重期合并肺栓塞早期筛选具有价值,两种方法结合可以提高诊断的准确性,降低漏诊率。     

Chronic thromboembolic and pulmonary arterial hypertension share acute vasoreactivity properties

BACKGROUND: Pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) are the major classes of pulmonary hypertensive disorders according to the World Health Organization; both lead to right heart failure and death. A better understanding of disease mechanisms has led to the suggestion that the thromboembolic and nonthromboembolic types of pulmonary hypertension may share pathophysiologic features. We therefore compared acute vasoreactivity and proximal pulmonary artery compliance in patients with PAH and CTEPH during the initial diagnostic heart catheterization. METHODS: Right heart catheterization using a flow-directed Swan-Ganz catheter was performed in patients with CTEPH (n = 22) and PAH (n = 35). Pulmonary hemodynamics were assessed at baseline, during the inhalation of 40 ppm of nitric oxide, and 30 min after the inhalation of 10 mug of iloprost. To assess the proximal pulmonary artery compliance, the pulse pressure (PP) [systolic-diastolic pressure] and the fractional PP (PPf) [divided by the mean pressure] were calculated. RESULTS: Both vasodilators produced similar hemodynamic improvement, and the difference between CTEPH and PAH was not significant. The baseline PP and PPf did not vary between the two groups. CONCLUSION: Patients with PAH and CTEPH show similar acute vasoreactivity to inhaled nitric oxide and iloprost, and have similar pulmonary artery compliance. These findings support the presence of some shared pathophysiologic pathways in both disorders and may lead to therapeutic implications in patients with inoperable CTEPH.     

肺心病合并肺血栓栓塞40例临床分析

目的 探讨COPD所致慢性肺原性心脏病并肺血栓栓塞（PTE）临床表现特点。方法 回顾性分析40例COPD所致肺心病合并PTE与单纯的COPD所致慢性肺心病40例进行对比。结果 肺心病合并肺栓塞组顽固性右心衰的发生率高、肺动脉压明显升高；氧分压明显下降，与单纯肺心病组比较，差异有显著性（P〈0．05）。结论 在诊断COPD所致慢性肺心病时，遇有难于解释的顽固性右心衰、高肺动脉压及低氧血症时应警惕合并PTE，尽快作胸部CT肺动脉造影或磁共振肺动脉造影（MRIPA）等检查以进一步明确诊断。     

Improvement after angioplasty and stenting of pulmonary arteries due to sarcoid mediastinal fibrosis

We describe a series of cases referred to our institution with working diagnoses of chronic thrombo-embolic pulmonary hypertension (CTEPH) for consideration of surgical pulmonary thrombo-endarterectomy (PTE). Investigations in two cases revealed extrinsic compression of the pulmonary arteries from massive mediastinal lymphadenopathy (mediastinal fibrosis) due to underlying sarcoidosis. Angioplasty and stenting of the pulmonary arteries were performed in all cases with sustained haemodynamic and functional improvement. This highlights the value of new imaging modalities in delineating causes of pulmonary hypertension, and demonstrates an interventional approach for selected cases.