Pulmonary hypertension and cor pulmonale

Summary Pulmonary hypertension is a severe disorder of the pulmonary circulation and occurs in a variety of vascular and parenchymal lung diseases. It leads to volume and/or pressure overload of the right ventricle and finally to right heart failure. Pulmonary vascular diseases such as chronic pulmonary embolism cause a drastic increase in pulmonary vascular resistance, which results in extremely high pulmonary artery pressures that can even reach systemic levels. On the other hand, moderate pulmonary hypertension can also occur in chronic obstructive and restrictive lung diseases. For a long time, the diagnosis of pulmonary hypertension and cor pulmonale was based upon findings in echocardiography and right heart catheterization. Today modern imaging techniques allow the radiologist to assess right ventricular and pulmonary artery morphology and function. The application of spiral CT, electron-beam CT and MRT permits the diagnosis and differential diagnosis of pulmonary hypertension and also the evaluation and follow-up of underlying vascular or parenchymal lung disorders. In addition, quantification of right ventricular function and calculation of pulmonary hemodynamic parameters are possible. Eingegangen am 28. Januar 1997 Angenommen am 5. Februar 1997     

Unresolved major pulmonary embolism: Importance of follow-up lung scan in diagnosis

Unresolved major pulmonary embolism (UMPE) is an uncommon condition which causes pulmonary hypertension, cor pulmonale and death. An accurate and prompt diagnosis of UMPE is very important in the management of such patients with pulmonary embolectomy. Follow-up lung scans can lead to earlier diagnosis of UMPE, especially in patients who have a history of acute pulmonary embolism and present with pulmonary hypertension, respiratory insufficiency and cor pulmonale. We report a case of UMPE strongly suggested by follow-up lung scans and subsequently confirmed by pulmonary angiography and postmortem examination.     

Unresolved major pulmonary embolism: importance of follow-up lung scan in diagnosis

Unresolved major pulmonary embolism (UMPE) is an uncommon condition which causes pulmonary hypertension, cor pulmonale and death. An accurate and prompt diagnosis of UMPE is very important in the management of such patients with pulmonary embolectomy. Follow-up lung scans can lead to earlier diagnosis of UMPE, especially in patients who have a history of acute pulmonary embolism and present with pulmonary hypertension, respiratory insufficiency and cor pulmonale. We report a case of UMPE strongly suggested by follow-up lung scans and subsequently confirmed by pulmonary angiography and postmortem examination.     

Application of a new pulmonary artery obstruction score in the prognostic evaluation of acute pulmonary embolism: comparison with clinical and haemodynamic parameters

Purpose

Evaluation of computed tomography (CT) pulmonary angiography parameters revealing pulmonary embolism (PE) severity with particular attention to pulmonary obstruction indexes. Comparison with clinical and hemodynamic data and determination of predictive role in the development of chronic pulmonary heart disease.

Materials and methods

This retrospective study analyzes 45 not consecutive patients from November 2007 to December 2008 with CT angiography diagnosis of acute PE. Included in the study are patients at the first documented episode of acute PE, with 6 month follow-up. Patients with severe pre-existent cardiopulmonary pathology or neoplastic diseases were excluded from the study. CT angiography evaluated right ventricular (RV)/left ventricular (LV) ratio, obstruction index according to Qanadli and Total Clot Burden (Ghanima score). PE indexes were compared with Troponin I measurement and echocardiography result; at last hospitalization and intensive care time were reported.

Results

A significant association was found between Ghanima and Qanadli score: the two indexes are equivalent in quantification of pulmonary arterial obstruction (p<0.001). Among others CT parameters, the new Ghanima score evidenced the best accuracy to detect patients evolving to chronic pulmonary heart disease (76%). This value is higher than that of echocardiography (71%). Troponins showed highest accuracy (82%).

Conclusions

Ghanima score can be used in emergency CT angiography diagnosis as prognostic marker for a quickly risk stratification of pulmonary heart disease or death in patients with acute PE. This approach allows to obtain, with just one test, both the diagnosis and a rather accurate acute PE risk stratification.     

Role of helical CT in detecting right ventricular dysfunction secondary to acute pulmonary embolism

OBJECTIVE: The purpose of this study was to evaluate the role of helical CT in detecting right ventricular dysfunction (RVD) after acute pulmonary embolism (PE). METHODS: This was a retrospective study consisting of 25 patients with CT scans positive for acute pulmonary embolism who had either follow-up echocardiography (23 patients) or pulmonary angiography (2 patients). CT scans were reviewed for findings suggestive of RVD. Scans were considered positive for RVD if the right ventricle (RV) was dilated or if the interventricular septum was deviated towards the left ventricle. Results were then correlated with the results of echocardiography or pulmonary angiography to estimate the sensitivity and specificity of CT in detecting RVD associated with PE. RESULTS: Within this group of 25 patients with PE, CT demonstrated sensitivity of 78% (7/9), specificity of 100% (16/16), and positive predictive value of 100% (7/7) in detection of RVD. CONCLUSION: CT may be useful in detecting RVD in patients with acute PE.     

Severity of acute pulmonary embolism: evaluation of a new spiral CT angiographic score in correlation with echocardiographic data

The purpose of this study was to investigate whether the severity of acute pulmonary embolism (PE) could be quantitatively assessed with spiral CT angiography (SCTA). Thirty-six consecutive patients without underlying cardiopulmonary disease and high clinical suspicion of PE underwent prospectively thin-collimation SCTA and echocardiography at the time of the initial diagnosis (T0) and after initial therapy (T1; mean interval of time T1–T2: 32 days). The CT severity score was based on the percentage of obstructed surface of each central and peripheral pulmonary arterial section using a 5-point scale (1: <25%; 2: 25–49%; 3: 50–74%; 4: 75–99%; 5: 100%). The sum of the detailed scores attributed to 5 mediastinal, 6 lobar and 20 segmental arteries per patient led to the determination of central, peripheral and global CT severity scores and subsequent determination of percentages of obstruction of the pulmonary circulation. Echocardiographic severity criteria included the presence of signs of acute cor pulmonale and/or systolic pulmonary hypertension (>40 mm Hg). The SCTA depicted acute PE in all patients at T0 with complete resolution of endovascular clots in 10 patients at T1. At T0, the mean percentage of obstruction of the pulmonary arterial bed was significantly higher in the 22 patients with echocardiographic signs of severity (56±13 vs 28±32%; p<0.001). A significant reduction in the mean percentage of pulmonary artery obstruction was observed in the 19 patients with resolution of echocardiographic criteria of severity between T0 and T1 T0: 57±14%; T1: 7±11%; p<0.001).The threshold value for severe PE on CT angiograms was 49% (sensitivity: 0.773; specificity: 0.214). The mean (±SD) pulmonary artery pressure was significantly higher in the 26 patients with more than 50% obstruction of the pulmonary artery bed (45±15 mm Hg) than in the 10 patients with less than 50% obstruction of pulmonary artery bed at T0 (31±11 mm Hg; p<0.01). The CT severity score evaluated in the present study enables quantitative assessment of acute PE severity on spiral CT angiograms, readily applicable in routine clinical practice. Electronic Publication     

MDCT of acute thrombotic and nonthrombotic pulmonary emboli

Acute pulmonary embolism (PE) remains a common clinical challenge. MDCT pulmonary angiography has become the first line imaging study in the diagnosis of PE because of its speed, accuracy, low-interobserver variability, and ability to provide alternative diagnoses. This review article highlights the role of MDCT in the evaluation of acute thrombotic PE in the era of PIOPED 2. MDCT findings of acute PE and some potential pitfalls are covered as well as some of the controversies in imaging young and pregnant patients. MDCT findings of acute non-thrombotic PE are also covered. This latter group may be occult on the angiographic portion of the study but may declare themselves through secondary findings. Their findings and potential mimics are included so that the interpreting radiologist can make the most of a CT to rule out PE.     

超声检查在急性肺栓塞诊断中的应用价值

目的 探讨超声检查在急性肺栓塞诊断中的应用价值。方法 对临床综合诊断为急性肺栓塞的15例病人行超声心动图检查，综合分析。结果 经超声心动图检查15例患者，发现右房内血栓1例，肺动脉内血栓1例。15例均有右心负荷过重表现，伴有不同程度的三尖瓣返流，返流速度加快，肺动脉压明显增高。7例发现下肢深静脉内血栓。结论 超声心动图在肺动脉栓塞病人的筛查、评价患者的右心功能及疗效方面有重要价值。     

Ischemia of right ventricle and cor pulmonale

48 year old man with chronic obstructive pulmonary disease (COPD) secondary to pulmonary hypertension with domiciliary non-invasive ventilation was seen. He came to the emergency department with acute exacerbation of COPD. The patient was admitted to the Cardiology Service with the diagnosis of congestive heart failure. Diagnostic imaging (chest X-ray, transthoracic Doppler-echocardiography, multidetector row spiral CT and myocardial perfusion imaging) revealed an enlarged right ventricle. ECG was consistent with right ventricular failure. The heart perfusion imaging (pharmacologic stress testing with dobutamine) showed cor pulmonale and right ventricle ischemia induced by drug stress with dobutamine. Although right ventricle myocardial chronic dysfunction rarely causes right ventricular failure, it can occur when cor pulmonale and ischemia heart disease are present.     

肺心病X线诊断的难点与限度(附100例分析)

目的　分析慢性肺心病的X线征象 ,探讨其诊断的难点与限度。方法　分析 10 0例肺心病X线检查结果 ,并与ECG及B超的检查结果进行比较。结果　 (1)肺心病患者心脏不增大或缩小时 ,判定右心室肥厚主要根据侧位片心前缘隆凸伴密度增大 ;(2 )正侧位片未能清楚显示肺动脉段和肺门血管结构者 ,须摄加深曝光片 ,肺门体层摄影或CT检查 ,以助判定肺动脉高压 ;(3 )肺心病并冠心病的诊断 ,应包括左心室中度增大 ,左心房轻大 ,肺淤血 /间质肺水肿等一组X线征象 ;(4 )ECG检出右室肥厚 ,并存心肌缺血和心率紊乱具有优点 ,B超判断房室腔大小 ,三尖瓣返流 ,左室壁运动异常优于X线。结论　X线 ,ECG及B超对肺心病 (或并有冠心病 )的诊断各具有优点及限度 ,为提高诊断正确率 ,宜兼作三项检查互为补充。     

Right ventricular dysfunction secondary to acute massive pulmonary embolism detected by helical computed tomography pulmonary angiography

OBJECTIVE: Acute massive pulmonary embolism causes abrupt pulmonary arterial hypertension and right ventricular dysfunction (RVD). Patients with RVD have a worse prognosis than those with normal right ventricular function. Consequently, recognizing the RVD at the time of pulmonary embolism is useful for risk stratification and enables more aggressive therapy. The study compared the accuracy of helical computed tomographic (CT) scans with echocardiography in the detecting of RVD in patients with acute massive pulmonary embolism. MATERIALS AND METHODS: Specifically, this work reviewed the CT pulmonary angiograms of 14 patients who were positive for acute massive pulmonary embolism during a 52-month period. CT scans were reviewed for findings indicating RVD. Scans were considered positive for RVD if the right ventricle was dilated or there was leftward shift of the interventricular septum. Echocardiographic reports serving as the reference standard for the diagnosis of RVD were also reviewed. CT study results were then correlated with echocardiography results. RESULTS: Among 14 patients with massive pulmonary embolism, echocardiography identified 12 patients having RVD, whereas the remaining two patients were negative for RVD. Meanwhile, CT correctly identified 11 of 12 patients as having RVD, and was negative for RVD in the remaining 3 patients. Correlated with echocardiography, CT scan for RVD detection had a sensitivity of 91.6% and a specificity of 100%. CONCLUSIONS: CT can accurately detect RVD in patients with acute massive pulmonary embolism. However, this result requires confirmation using a larger prospective cohort study.     

CT imaging of acute pulmonary embolism

CT pulmonary angiography (CTPA) has become the de facto clinical "gold standard" for the diagnosis of acute pulmonary embolism (PE) and has replaced catheter pulmonary angiography and ventilation-perfusion scintigraphy as the first-line imaging method. The factors underlying this algorithmic change are rooted in the high-sensitivity and specificity, cost-effectiveness, and 24-hour availability of CTPA. In addition, CTPA is superior to other imaging methods in its ability to diagnose and exclude, in a single examination, a variety of diseases that mimic the symptoms of PE. This article reviews the current role of CTPA in the diagnosis of acute PE as well as more recent developments, such as the use of CT parameters of right ventricular dysfunction for patient prognostication and the assessment of lung perfusion with CT.     

Pulmonary artery CTA

The latest with the introduction of multidetector row computed tomography (MDCT), CT has been firmly established as the modality of choice for imaging the pulmonary arteries, particularly as the de facto first line test for imaging patients with suspected acute pulmonary embolism (PE). Before the introduction of MDCT, remaining concerns regarding CTs accuracy for diagnosis of isolated peripheral emboli had prevented the unanimous acceptance of this test as the reference standard for imaging PE. After a decade of uncertainty, there is now conclusive evidence that CT, if positive, provides reliable confirmation of the presence of PE and, more importantly, if negative effectively rules out clinically significant PE. Current endeavors to streamline and facilitate workflow for CT diagnosis of PE will further improve the acceptance, utility, and importance of this test. Examples include improvements in workflow, CT derivation of right ventricular function parameters for triage and prognostication of patients with acute PE and the comprehensive assessment of patients with acute chest pain for PE, coronary disease, aortic disease, and pulmonary disease by means of a single, contrast enhanced, ECG-synchronized CT scan. Although the diagnosis or exclusion of acute PE is the most common and important application of CT pulmonary angiography, the ease of scan acquisition and the high spatial resolution of modern CT techniques make this test ideally suited for the greatest majority of congenital and acquired, acute and chronic disorders of the pulmonary arteries.     

Helical CT for the evaluation of suspected acute pulmonary embolism: diagnostic pitfalls

Helical CT is being increasingly utilized for the evaluation of suspected pulmonary embolism (PE). Proper scan interpretation depends on the awareness of several diagnostic pitfalls that may simulate PE, including normal bronchovascular structures such as pulmonary veins, bronchi, and lymph nodes, technical considerations such as improper bolus timing and streak artifacts, and patient-related factors such as motion artifacts, pulmonary arterial catheters, and vascular shunts. An understanding of these pitfalls facilitates accurate diagnosis.     

Multidetector-row CT in severe pulmonary embolism: radiologists' help in risk stratification

Multidetector-row computed tomographic (CT) angiography of pulmonary arteries is the first-line imaging technique in patients suspected of having pulmonary embolism (PE). Patient risk stratification is important because optimal management, monitoring, and therapeutic strategies depend on the patient's prognosis. Acute right-sided heart failure is known to be responsible for circulatory collapse and death in patients with severe PE. Acute right-sided heart failure can be assessed on CT pulmonary angiography by measuring the dimensions of the right-sided heart cavities or systemic veins. The magnitude of PE can be calculated on CT pulmonary angiography by applying dedicated CT scores or angiographic scores adapted. This article reviews and discusses the various CT-based methods for risk stratification of patients with acute PE.     

Multislice-CT bei akuter Lungenembolie

Multidetector-row computed tomographic (CT) angiography of pulmonary arteries is the first-line imaging technique in patients suspected of having pulmonary embolism (PE). Patient risk stratification is important because optimal management, monitoring, and therapeutic strategies depend on the patient’s prognosis. Acute right-sided heart failure is known to be responsible for circulatory collapse and death in patients with severe PE. Acute right-sided heart failure can be assessed on CT pulmonary angiography by measuring the dimensions of the right-sided heart cavities or systemic veins. The magnitude of PE can be calculated on CT pulmonary angiography by applying dedicated CT scores or angiographic scores adapted. This article reviews and discusses the various CT-based methods for risk stratification of patients with acute PE.     

CT angiography for diagnosis of pulmonary embolism: state of the art

In daily clinical routine, computed tomography (CT) has practically become the first-line modality for imaging of pulmonary circulation in patients suspected of having pulmonary embolism (PE). However, limitations regarding accurate diagnosis of small peripheral emboli have so far prevented unanimous acceptance of CT as the reference standard for imaging of PE. The development of multi-detector row CT has led to improved visualization of peripheral pulmonary arteries and detection of small emboli. The finding of a small isolated clot at pulmonary CT angiography, however, may be increasingly difficult to correlate with results of other imaging modalities, and the clinical importance of such findings is uncertain. Therefore, the most realistic scenario to measure efficacy of pulmonary CT angiography when PE is suspected may be assessment of patient outcome. Meanwhile, the high negative predictive value of a normal pulmonary CT angiographic study and its association with beneficial patient outcome has been demonstrated. While the introduction of multi-detector row technology has improved CT diagnosis of PE, it has also challenged its users to develop strategies for optimized contrast material delivery, reduction of radiation dose, and management of large-volume data sets created at those examinations.     

Computed tomography pulmonary angiogram diagnosis of pulmonary embolism

Over the last decade, contrast-enhanced spiral CT has been established as a non-invasive alternative to catheter angiography and is now regarded as the first-line imaging investigation for the diagnosis of pulmonary embolism (PE). The reported sensitivities for the diagnosis of PE of spiral CT vary from 45 to 100% and the specificities vary from 78 to 100%. Prospective outcome studies have shown a high negative predictive value for a single-detector spiral CT for PE. Patients' outcomes were not adversely affected in these studies when anticoagulation was withheld after a negative CT pulmonary angiogram. The main limitation of single-detector spiral CT has been its limited ability to detect isolated subsegmental PE. However, multidetector spiral CT allows evaluation of pulmonary vessels down to sixth-order branches and significantly increases the rate of detection of PE in segmental and subsegmental levels. The interobserver correlations for diagnosis of subsegmental PE with multidetector spiral CT exceed the reproducibility of selective pulmonary angiography. If appropriate equipment is available (multidetector CT), then CT pulmonary angiogram is safe to be used as the first-line imaging investigation for the diagnosis of PE.     

Accuracy of CT angiography versus pulmonary angiography in the diagnosis of acute pulmonary embolism: evaluation of the literature with summary ROC curve analysis

RATIONALE AND OBJECTIVES: The authors performed this study to estimate, by using published data, the sensitivity and specificity of computed tomographic (CT) angiography in the evaluation of suspected acute pulmonary embolism (PE). MATERIALS AND METHODS: Summary receiver operating characteristic (ROC) curve analysis was used to determine the sensitivity and specificity of CT angiography in the diagnosis of acute PE. Pulmonary angiography was used as the diagnostic standard of reference. The authors reviewed the results of 11 independent studies published in the English-language literature between January 1992 and June 1999. RESULTS: The sensitivity of CT angiography in the diagnosis or exclusion of PE in the central pulmonary arteries (to the level of the segmental pulmonary arteries) ranged from 0.74 to 0.81 on the basis of specificities of 0.89-0.91. The sensitivity of CT angiography in the diagnosis or exclusion of PE in all pulmonary arteries (to the level of the subsegmental pulmonary arteries) was 0.68 on the basis of a specificity of 0.91. CONCLUSION: On the basis of the studies in the current literature, most of which used 5.0-mm collimation and single-detector CT, CT angiography may be less accurate in the diagnosis of PE than previously reported. With improvements in data acquisition, particularly the use of thinner section collimation and multidetector CT, and in the increased use of workstations for data analysis, the accuracy and utility of CT angiography will require continued investigation.     

双能量CT肺灌注成像的定量参数诊断肺栓塞的临床应用价值

目的探讨双能量CT肺灌注成像(DEPI)的定量参数诊断肺栓塞的临床应用价值。方法选取40例疑似肺栓塞行双能量CT扫描并行CTPA及DEPI重建的患者影像资料,以肺段为评价单位,分析PE栓子的部位、栓塞程度以及肺灌注情况,测量感兴趣区的平均CT值及碘含量值与正常灌注区的比值,并进行统计学分析。结果40例患者分为非栓塞组13例,栓塞组24例,其他3例;栓塞组无栓塞肺段(201个)与非栓塞组肺段(200个)的平均CT值比值(t=-1.81,P>0.05)、碘含量比值(t=-1.541,P>0.05)差异无统计学意义;栓塞组栓塞肺段(204个)与无栓塞肺段(201个)的平均CT值比值(t=34.77,P<0.01)、碘含量比值(t=32.07,P<0.01)差异有统计学意义;栓塞组完全栓塞肺段(83个)与部分栓塞肺段(121个)的平均CT值比值(t=-17.54,P<0.01)、碘含量比值(t=-16.27,P<0.01)差异有统计学意义。ROC曲线分析显示DEPI定量参数对肺栓塞具有良好的诊断效能,平均CT值及碘含量值<40.65 HU、1.75 mg/ml临界值时,诊断PE的敏感度分别为96.0%、92.0%,特异度分别为88.6%、90.0%。结论DEPI定量参数能够作为诊断PE的有效指标,具有较高的敏感度和特异度,对PE治疗前后的评估提供更加全面、客观的依据。