Pulmonary neovascularity: a distinctive radiographic finding in Eisenmenger syndrome

Imaging Features in BMPR2 Mutation-associated Pulmonary Arterial Hypertension

Background Germline mutation in the BMPR2 gene is common in patients with pulmonary arterial hypertension (PAH). However, its association with imaging findings in these patients is, to the knowledge of the authors, unknown. Purpose To characterize distinctive pulmonary vascular abnormalities at CT and pulmonary artery angiography in patients with and without BMPR2 mutation. Materials and Methods In this retrospective study, chest CT scans, pulmonary artery angiograms, and genetic test data were acquired for patients diagnosed with idiopathic PAH (IPAH) or heritable PAH (HPAH) between January 2010 and December 2021. Perivascular halo, neovascularity, centrilobular ground-glass opacity (GGO), and panlobular GGO were evaluated at CT and graded on a four-point severity scale by four independent readers. Clinical characteristics and imaging features between patients with BMPR2 mutation and noncarriers were analyzed using the Kendall rank-order coefficient and the Kruskal-Wallis test. Results This study included 82 patients with BMPR2 mutation (mean age, 38 years ± 15 [SD]; 34 men; 72 patients with IPAH and 10 patients with HPAH) and 193 patients without the mutation, all with IPAH (mean age, 41 years ± 15; 53 men). A total of 115 patients (42%; 115 of 275) had neovascularity, and 56 patients (20%; 56 of 275) had perivascular halo at CT, and so-called frost crystals were observed on pulmonary artery angiograms in 14 of 53 (26%) patients. Compared with patients without BMPR2 mutation, patients with BMPR2 mutation more frequently showed two distinctive radiographic manifestations, perivascular halo and neovascularity (38% [31 of 82] vs 13% [25 of 193] in perivascular halo [P < .001] and 60% [49 of 82] vs 34% [66 of 193] in neovascularity [P < .001], respectively). "Frost crystals" were more frequent in patients with BMPR2 mutation compared with noncarriers (53% [10 of 19] vs 12% [four of 34]; P < .01). Severe perivascular halo frequently coexisted with severe neovascularity in patients with BMPR2 mutation. Conclusion Patients with PAH with BMPR2 mutation showed distinctive features at CT, specifically perivascular halo and neovascularity. This suggested a link between the genetic, pulmonary, and systemic manifestations that underly the pathogenesis of PAH. © RSNA, 2023 Supplemental material is available for this article.

Computed tomography lung parenchymal descriptions in routine radiological reporting have diagnostic and prognostic utility in patients with idiopathic pulmonary arterial hypertension and pulmonary hypertension associated with lung disease

BACKGROUND

Patients with pulmonary hypertension (PH) and lung disease may pose a diagnostic dilemma between idiopathic pulmonary arterial hypertension (IPAH) and PH associated with lung disease (PH-CLD). The prognostic impact of common computed tomography (CT) parenchymal features is unknown.

METHODS

660 IPAH and PH-CLD patients assessed between 2001 and 2019 were included. Reports for all CT scans 1 year prior to diagnosis were analysed for common lung parenchymal patterns. Cox regression and Kaplan-Meier analysis were performed.

RESULTS

At univariate analysis of the whole cohort, centrilobular ground-glass (CGG) changes (hazard ratio, HR 0.29) and ground-glass opacification (HR 0.53) predicted improved survival, while honeycombing (HR 2.79), emphysema (HR 2.09) and fibrosis (HR 2.38) predicted worse survival (all p<0.001). Fibrosis was an independent predictor after adjusting for baseline demographics, PH severity and diffusing capacity of the lung for carbon monoxide (HR 1.37, p<0.05). Patients with a clinical diagnosis of IPAH who had an absence of reported parenchymal lung disease (IPAH-noLD) demonstrated superior survival to patients diagnosed with either IPAH who had coexistent CT lung disease or PH-CLD (2-year survival of 85%, 60% and 46%, respectively, p<0.05). CGG changes were present in 23.3% of IPAH-noLD and 5.8% of PH-CLD patients. There was no significant difference in survival between IPAH-noLD patients with or without CGG changes. PH-CLD patients with fibrosis had worse survival than those with emphysema.

INTERPRETATION

Routine clinical reports of CT lung parenchymal disease identify groups of patients with IPAH and PH-CLD with significantly different prognoses. Isolated CGG changes are not uncommon in IPAH but are not associated with worse survival.

CT Appearance of Pulmonary Arteriovenous Malformations and Mimics

A pulmonary arteriovenous malformation (PAVM) is a fistulous connection between a pulmonary artery and a pulmonary vein that bypasses the normal pulmonary capillary bed resulting in a right-to-left shunt. Because of the potential for paradoxical emboli, PAVMs are treated when their feeding arteries exceed 3 mm or patients are symptomatic. PAVMs are often encountered in patients with suspected hereditary hemorrhagic telangiectasia (HHT). Sporadic cases are uncommon. The radiologist may be called on to diagnose a PAVM after positive transthoracic contrast-enhanced echocardiography in a patient with suspected HHT to direct patient management and avoid potential complications. The radiologist may also be required to evaluate a potential PAVM detected at CT performed for other reasons. Through the authors' experiences at an HHT Center of Excellence in an area endemic with histoplasmosis, the authors have gained a unique perspective on the diagnosis of PAVMs and differentiation of PAVMs from their mimics. Understanding the CT appearance of PAVMs limits misdiagnosis, directs appropriate treatment, and allows subsequent family screening for HHT (and avoidance of unnecessary screening when a PAVM mimic is encountered). Both vascular and nonvascular pulmonary lesions can mimic PAVMs. Vascular mimics include fibrosing mediastinitis, venovenous collaterals, arterial collaterals, pulmonary artery pseudoaneurysms, hepatopulmonary vessels, Sheehan vessels, meandering pulmonary veins, and pulmonary vein varices. Nonvascular mimics include granulomas, nodules, mucoceles, bronchoceles, ground-glass opacities, and atelectasis. The authors review the CT technique for evaluating PAVMs and the appearance of PAVMs and their mimics. ^©RSNA, 2022.

Micronodular lung disease on high-resolution CT: patterns and differential diagnosis

With the advent of high-resolution computed tomography (HRCT), micronodular lung disease is a routinely encountered pathology in thoracic imaging. This article will review how to differentiate the three main micronodular patterns and review the differential diagnosis for each. Differential diagnosis of micronodular lung disease may be extensive, but by identifying the pattern and using additional clues, such as distribution, additional imaging findings, and clinical history, a radiologist can make an accurate diagnosis. First, three micronodular patterns - centrilobular, peri-lymphatic, and random - can be identified by using a simple algorithm based on the location of nodules. This algorithm requires understanding of the anatomy and function of the secondary pulmonary lobule. Each micronodular pattern offers a unique differential diagnosis. Centrilobular nodules can be seen with inflammatory, infectious, or vascular aetiologies; peri-lymphatic nodules with sarcoidosis and lymphangitic carcinomatosis; and random nodules with haematogenous metastases or infections.

The investigation and diagnosis of pulmonary hypertension in adults with congenital heart disease

Pulmonary hypertension is not uncommon in adult patients with congenital heart disease and can significantly affect their exercise capacity, quality of life and prognosis. Timely identification and management of pulmonary hypertension in these patients is important. Patients must be allocated to the correct diagnostic group and treatment decided upon, including offering pulmonary arterial hypertension therapies to those who are most likely to benefit.

In this paper, we provide an overview of the diagnostic modalities that are used to investigate and diagnose pulmonary hypertension in modern adult congenital heart disease practice. Emphasis is placed on echocardiography, which is the modality of choice for raising the suspicion of PH, and cardiac catheterisation, which is fundamental in establishing the diagnosis. Other modalities, such as cardiac magnetic resonance imaging and computed tomography can provide complementary information on anatomy and physiology.

Combining all this information into a clinical diagnosis and management plan requires clinical expertise and a multidisciplinary approach, especially when managing this rare and complex group of patients.

Computed tomographic and clinical features of pulmonary veno-occlusive disease: raising the radiologist's awareness

Pulmonary veno-occlusive disease (PVOD) is a rare subtype of pulmonary arterial hypertension (PAH) characterised by preferential remodelling of the pulmonary venules. Differentiation from other subtypes of PAH is essential as the management can differ significantly; for example, initiation of vasodilator therapy may cause fatal pulmonary oedema in a patient with PVOD misdiagnosed with idiopathic PAH. PVOD also carries a substantially worse prognosis. Lung biopsy is required for definitive diagnosis, but this is hazardous, and ideally, should be avoided in pulmonary hypertension. Computed tomography (CT) may suggest the diagnosis, directing the patient towards specialist review. Potential distinguishing CT features between PVOD and other subtypes of PAH include interlobular septal thickening, mediastinal lymphadenopathy, and centrilobular ground-glass opacities. No evidence-based medical therapy exists for PVOD at present and lung transplantation remains the definitive treatment for eligible patients. Therefore, early radiological identification of this challenging diagnosis facilitates timely referral for transplant.

Idiopathic, heritable and veno-occlusive pulmonary arterial hypertension in childhood: computed tomography angiography features in the initial assessment of the disease

BACKGROUND

In children, idiopathic and heritable pulmonary arterial hypertension present echocardiographic and heart catheterization findings similar to findings in pulmonary veno-occlusive disease.

OBJECTIVE

To provide a systematic analysis of CT angiography anomalies in children with idiopathic or heritable pulmonary arterial hypertension, or pulmonary veno-occlusive disease. We also sought to identify correlations between CT findings and patients' baseline characteristics.

MATERIALS AND METHODS

We retrospectively analyzed CT features of children with idiopathic and heritable pulmonary arterial hypertension or pulmonary veno-occlusive disease and 30 age-matched controls between 2008 and 2014. We compared CT findings and patient characteristics, including gene mutation type, and disease outcome until 2017.

RESULTS

The pulmonary arterial hypertension group included idiopathic (n=15) and heritable pulmonary arterial hypertension (n=11) and pulmonary veno-occlusive disease (n=4). Median age was 6.5 years. Children with pulmonary arterial hypertension showed enlargement of pulmonary artery and right cardiac chambers. A threshold for the ratio between the pulmonary artery and the ascending aorta of ≥1.2 had a sensitivity of 90% and a specificity of 100% for pulmonary arterial hypertension. All children with pulmonary veno-occlusive disease had thickened interlobular septa, centrilobular ground-glass opacities, and lymphadenopathy. In children with idiopathic and heritable pulmonary arterial hypertension, presence of intrapulmonary neovessels and enlargement of the right atrium were correlated with higher mean pulmonary artery pressure (P=0.011) and pulmonary vascular resistance (P=0.038), respectively. Mediastinal lymphadenopathy was associated with disease worsening within the first 2 years of follow-up (P=0.024).

CONCLUSION

CT angiography could contribute to early diagnosis and prediction of severity in children with pulmonary arterial hypertension.

Current and emerging imaging techniques in the diagnosis and assessment of pulmonary hypertension

INTRODUCTION

Pulmonary hypertension (PH) is a challenging condition to diagnose and treat. Over the last two decades, there have been significant advances in therapeutic approaches and imaging technologies. Current guidelines emphasize the importance of cardiac catheterization; however, the increasing availability of non-invasive imaging has the potential to improve diagnostic rates, whilst providing additional information on patient phenotypes. Areas covered: This review discusses the role of imaging in the diagnosis, prognostic assessment and follow-up of patients with PH. Imaging methods, ranging from established investigations (chest radiography, echocardiography, nuclear medicine and computerized tomography (CT)), to emerging modalities (dual energy CT, magnetic resonance imaging (MRI), optical coherence tomography and positron emission tomography (PET)) are reviewed. The value and limitations of the clinical utility of these imaging modalities and their potential clinical application are reviewed. Expert commentary: Imaging plays a key role in the diagnosis and classification of pulmonary hypertension. It also provides valuable prognostic information and emerging evidence supports a role for serial assessments. The authors anticipate an increasing role for imaging in the pulmonary hypertension clinic. This will reduce the need for invasive investigations, whilst providing valuable insights that will improve our understanding of disease facilitate a more targeted approach to treatment.

Approach to Pulmonary Hypertension: From CT to Clinical Diagnosis

Pulmonary hypertension (PH) is a condition characterized by increased pressure in the pulmonary circulation. It may be idiopathic or arise in the setting of other clinical conditions. Patients with PH tend to present with nonspecific cardiovascular or respiratory symptoms. The clinical classification of PH was recently revised at the World Health Organization symposium in Nice, France, in 2013. That consensus statement provided an updated classification based on the shared hemodynamic characteristics and management of the different categories of PH. Some features seen at computed tomography (CT) can suggest a subtype or probable cause of PH that may facilitate placing the patient in the correct category. These features include findings in the pulmonary arteries (peripheral calcification, peripheral dilatation, eccentric filling defects, intra-arterial soft tissue), lung parenchyma (centrilobular nodules, mosaic attenuation, interlobular septal thickening, bronchiectasis, subpleural peripheral opacities, ground-glass opacities, diffuse nodules), heart (congenital lesions, left heart disease, valvular disease), and mediastinum (hypertrophied bronchial arteries). An approach based on identification of these CT features in patients with PH will allow the radiologist to play an important role in diagnosis and help guide the clinician in management of PH. ^©RSNA, 2018.

Lung perfusion characteristics in pulmonary arterial hypertension (PAH) and peripheral forms of chronic thromboembolic pulmonary hypertension (pCTEPH): Dual-energy CT experience in 31 patients

PURPOSE

To compare lung perfusion in PAH and pCTEPH on dual-energy CT (DECT) examinations.

MATERIALS AND METHODS

Thirty-one patients with PAH (group 1; n = 19) and pCTEPH (group 2; n = 12) underwent a dual-energy chest CTA with reconstruction of diagnostic and perfusion images. Perfusion alterations were analysed at a segmental level. V/Q scintigraphy was available in 22 patients (group 1: 13/19; group 2: 9/12).

RESULTS

CT perfusion was abnormal in 52.6 % of group 1 patients and in 100 % of group 2 patients (p = 0.0051). The patterns of perfusion alteration significantly differed between the two groups (p < 0.0001): (1) in group 1, 96.6 % of segments with abnormal perfusion showed patchy defects; (2) in group 2, the most frequent abnormalities consisted of patchy (58.5 %) and PE-type (37.5 %) defects. Paired comparison of CT perfusion and scintigraphy showed concordant findings in 76.9 % of group 1 (10/13) and 100 % of group 2 (9/9) patients, with a predominant or an exclusive patchy pattern in group 1 and a mixed pattern of abnormalities in group 2.

CONCLUSION

Lung perfusion alterations at DECT are less frequent and more homogeneous in PAH than in pCTEPH, with a high level of concordant findings with V/Q scintigraphy.

KEY POINTS

• Depiction of chronic pulmonary embolism exclusively located on peripheral arteries is difficult. • The main differential diagnosis of pCTEPH is PAH. • The pattern of DECT perfusion changes can help differentiate PAH and pCETPH. • In PAH, almost all segments with abnormal perfusion showed patchy defects. • In pCTEPH, patchy and PE-type defects were the most frequent abnormalities.

Arterial aging: pathophysiological principles

In the nineteenth century, prior to the introduction of the cuff sphygmomanometer, arteriosclerosis (stiffening of arteries) was recognized by clinicians and by life insurance companies as an indicator of vascular aging and cardiovascular risk, even in asymptomatic individuals. Through the twentieth century, views on aging came to focus on values of systolic and diastolic pressure and on obstructive atherosclerotic disease. Such focus deflected attention from the primary aging change which occurs in all societies, and is represented by stiffening and dilation of the proximal aorta. This review emphasizes the cushioning function of elastic arteries — principally the aorta — and how in youth this results in optimal interaction with the heart, and optimal steady flow through peripheral resistance vessels. Aortic stiffening with age is principally due to fatigue and fracture of elastin lamellae, with transfer of stress to stiffer collagenous components. Stiffening increases left ventricular load and myocardial blood requirement, but limits the capacity for blood supply during diastole. Consequences are cardiac failure and predisposition to ischaemia. The second, under-appreciated effect of aortic stiffening is transmission of flow pulsations downstream into vasodilated organs, principally brain and kidney, where pulsatile energy is dissipated and fragile microvessels are damaged. This accounts for micro infarcts and microhaemorrhages, with specialized cell damage, cognitive decline and renal failure. The aging process can be best monitored by change in the arterial pressure wave rather than by reliance on the cuff sphygmomanometer. This reintroduces the approaches by clinicians and life insurance examiners of the nineteenth century, endorses modern treatments for established disease, and holds the promise of detecting premature arterial degeneration, and better applying lifestyle measures and vasoactive medications to modify the aging process.

Quantification of tortuosity and fractal dimension of the lung vessels in pulmonary hypertension patients

Pulmonary hypertension (PH) can result in vascular pruning and increased tortuosity of the blood vessels. In this study we examined whether automatic extraction of lung vessels from contrast-enhanced thoracic computed tomography (CT) scans and calculation of tortuosity as well as 3D fractal dimension of the segmented lung vessels results in measures associated with PH.

In this pilot study, 24 patients (18 with and 6 without PH) were examined with thorax CT following their diagnostic or follow-up right-sided heart catheterisation (RHC). Images of the whole thorax were acquired with a 128-slice dual-energy CT scanner. After lung identification, a vessel enhancement filter was used to estimate the lung vessel centerlines. From these, the vascular trees were generated. For each vessel segment the tortuosity was calculated using distance metric. Fractal dimension was computed using 3D box counting. Hemodynamic data from RHC was used for correlation analysis.

Distance metric, the readout of vessel tortuosity, correlated with mean pulmonary arterial pressure (Spearman correlation coefficient: ρ = 0.60) and other relevant parameters, like pulmonary vascular resistance (ρ = 0.59), arterio-venous difference in oxygen (ρ = 0.54), arterial (ρ = −0.54) and venous oxygen saturation (ρ = −0.68). Moreover, distance metric increased with increase of WHO functional class. In contrast, 3D fractal dimension was only significantly correlated with arterial oxygen saturation (ρ = 0.47).

Automatic detection of the lung vascular tree can provide clinically relevant measures of blood vessel morphology. Non-invasive quantification of pulmonary vessel tortuosity may provide a tool to evaluate the severity of pulmonary hypertension.

Trial Registration

ClinicalTrials.gov NCT01607489

Congenital heart disease and pulmonary hypertension

Many patients with congenital heart disease and systemic-to-pulmonary shunts develop pulmonary arterial hypertension (PAH), particularly if the cardiac defect is left unrepaired. A persistent increase in pulmonary blood flow may lead to obstructive arteriopathy and increased pulmonary vascular resistance, a condition that can lead to reversal of shunt and cyanosis (Eisenmenger syndrome). Cardiac catheterization is crucial to confirm diagnosis and facilitate treatment. Bosentan is the only medication to date to be compared with placebo in a randomized controlled trial specifically targeting congenital heart disease-associated PAH. Lung transplantation with repair of the cardiac defect or combined heart-lung transplantation is reserved for recalcitrant cases.

Lung neovascularity in pulmonary arterial hypertension associated with congenital heart defects and idiopathic pulmonary arterial hypertension: study of 198 patients

OBJECTIVES

To correlate the severity of lung neovascularity (Sheehan vessels) with the cause and haemodynamic severity of pulmonary arterial hypertension (PAH), pulmonary artery (PA) size and heart disease type in patients with PH associated with congenital heart diseases (PAH-CHD) and idiopathic PH (IPAH).

METHODS

We reviewed the HRCT and CT pulmonary angiography studies of 87 patients with PAH-CHD and 111 with IPAH; all had undergone right heart catheterisation. We evaluated the PA size and severity of neovascularity on CT.

RESULTS

Neovascularity, which was found in 72% of PAH-CHD (56% with Eisenmenger's syndrome) and in 22% of IPAH patients, is significantly related to the severity of PH and all patients with severe neovascularity had intermediate or high PH. All PAH-CHD patients had a dilated PA with a greater risk of developing severe dilatation (diameter >5 cm). The neovascularity correlated with the PA size only in IPAH.

CONCLUSIONS

Neovascularity even if not pathognomonic for PAH-CHD, is significantly more common in these patients, especially in Eisenmenger's syndrome. It is often the first CT sign to indicate the severity of PH in PAH-CHD and IPAH. A neovascularity ≥5 on CT indicates a intermediate or high PH.

KEY POINTS

• Large retrospective studying specific lung disorders in patients with pulmonary arterial hypertension. • Neovascularity is often the first CT sign indicating the severity of pulmonary hypertension Alterations of lung parenchyma on CT in pulmonary hypertension are described • The first study to assess the severity of pulmonary hypertension by CT • If substantiated, CT might eventually replace some cardiac catheterisation for evaluating PH.

Computed tomography and magnetic resonance imaging of pulmonary hypertension: Pulmonary vessels and right ventricle

Pulmonary hypertension (PH) is very heterogeneous and the classification identifies five major groups including many associated disease processes. The treatment of PH depends on the underlying cause and accurate classification is paramount. A comprehensive assessment to identify the cause and severity of PH is therefore needed. Furthermore, follow-up assessments are required to monitor changes in disease status and response to therapy. Traditionally, the diagnostic imaging work-up of PH comprised mainly echocardiography, invasive right heart catheterization, and ventilation/perfusion scintigraphy. Due to technical advances, multidetector row computed tomography (CT) and magnetic resonance imaging (MRI) have become important and complementary investigations in the evaluation of patients with suspected PH. Both modalities are reviewed and recommendations for clinical use are given.

Advances in diagnosis and treatment of pulmonary arterial hypertension in neonates and children with congenital heart disease

BACKGROUND

This article aims to review recent advances in the diagnosis and treatment of pulmonary arterial hypertension in neonates and children with congenital heart disease.

DATA SOURCES

Articles on pulmonary arterial hypertension in congenital heart disease were retrieved from PubMed and MEDLINE published after 1958.

RESULTS

A diagnosis of primary (or idiopathic) pulmonary arterial hypertension is made when no known risk factor is identified. Pulmonary arterial hypertension associated with congenital heart disease constitutes a heterogenous group of conditions and has been characterized by congenital systemic-to-pulmonary shunts. Despite the similarities in histologic appearance of pulmonary vascular disease, there are differences between pulmonary arterial hypertension secondary to congenital systemic-to-pulmonary shunts and those with other conditions with respect to pathophysiology, therapeutic strategies, and prognosis. Revision and subclassification within the category of secondary pulmonary arterial hypertension based on pathophysiology were conducted to improve specific treatments. The timing of surgical repair is crucial to prevent and minimize risk of postoperative pulmonary arterial hypertension. Drug therapies including prostacyclin, endothelin-receptor antagonist, phosphodiesterase inhibitor, and nitric oxide have been evolved with promising results in neonates and children.

CONCLUSIONS

Among the different forms of congenital heart diseases, an early correction generally prevents subsequent development of pulmonary arterial hypertension. Emerging therapies for treatment of patients with idiopathic pulmonary arterial hypertension also improve quality of life and survival in neonates and children with congenital heart disease associated with pulmonary arterial hypertension. Heart and lung transplantation or lung transplantation in combination with repair of the underlying cardiac defect is a therapeutic option in a minority of patients. Partial repair options are also beneficial in some selected cases. Randomized controlled trials are needed to evaluate the safety and efficacy of these therapies including survival and long-term outcome.

Imaging of Small Airway Disease (SAD)

This article comprehensively reviews and illustrates the imaging features of small airway diseases. The authors discuss the imaging findings of small airway diseases in general and how to differentiate them from other findings that can be confused with small airway diseases. The authors also discuss the features that aid in diagnosing specific diseases that affect the small airways.

Embolisation of systemic-to-pulmonary collaterals in patients with the Eisenmenger reaction presenting with haemoptysis

Haemoptysis is a common feature of adults with congenitally malformed hearts suffering from Eisenmenger's syndrome. While this situation is often treated conservatively, it may not settle with such treatment. A further therapeutic option for these patients is embolisation of appropriate systemic-to-pulmonary collateral arteries. We discuss here our experience in treating two such patients with different underlying anatomical substrates.

Eisenmenger syndrome and idiopathic pulmonary arterial hypertension: do parenchymal lung changes reflect aetiology?

AIM

To document the pulmonary vascular changes on thin-section computed tomography (CT) in patients with Eisenmenger syndrome and idiopathic pulmonary arterial hypertension, and to determine whether there is any correlation with pulmonary arterial pressures or the aetiology of pulmonary hypertension.

MATERIAL AND METHODS

From the National Pulmonary Hypertension Database, we identified eight patients with idiopathic pulmonary arterial hypertension and 20 patients with Eisenmenger syndrome (secondary to a ventriculoseptal defect) who had also undergone contrast-enhanced thin-section CT. CT studies were reviewed for the presence of centrilobular nodules, mosaicism, neovascularity, and bronchial artery hypertrophy. Haemodynamic data were also reviewed.

RESULTS

Centrilobular nodules, mosaicism, and neovascularity were seen in both patient groups (p>0.05). A significantly higher number of enlarged bronchial arteries were seen in patients with Eisenmenger syndrome. There was no correlation with pulmonary arterial pressures.

CONCLUSION

Patients with idiopathic pulmonary arterial hypertension and Eisenmenger syndrome demonstrated similar pulmonary vascular changes on CT. These changes did not predict the underlying cause of pulmonary hypertension or its severity.