Central Pulmonary Vessels Research Articles

Rehabilitation of Pulmonary Arteries in Pulmonary Atresia, VSD and Mapcas

Patients with pulmonary atresia, Ventricular septal defect (VSD), and Major Aorto Pulmonary Collateral Arteries have a lung circulation depending primarily from perfusion by collateral arteries. A large proportion of them will have central pulmonary vessels connected to a variable proportion of segmental pulmonary vessels. A strategy of rehabilitation of central pulmonary vessels consist in the realization of shunts and conduits between the aorta or the right ventricle and these central vessels in order to obtain a dilatation of these vessels to assist the reconstruction of a pulmonary vascularization. Repetitive patch reconstruction of the central pulmonary vessels or even their replacement are often necessary. Additional procedural steps may be needed at the time of the repair to reconnect to the central pulmonary circulation large intrapulmonary vessels dependent of collateral flow.

Localized Fibrosing Mediastinitis Causing Pulmonary Infarction: A Case Report

Fibrosing mediastinitis is a rare benign disorder that is characterized by deposition of dense fibrous tissue throughout the mediastinum and hilar regions (1). Resultant infiltrative or compressive effects on vital mediastinal organs such as central systemic vein, airway, and pulmonary vessels, could increase morbidity and in rare circumstances even mortality (2). We reported a rare case of fibrosing mediastinitis causing pulmonary infarction by encasing pulmonary artery that was detected on chest computed tomography (CT).

Severe hypoxemia without pulmonary infiltrates in systemic lupus erythematosus

Fifty percent of systemic lupus erythematosus (SLE) patients have pulmonary disease which can involve the lung parenchyma, the pleural space, and pulmonary vessels. The article reviews the causes of severe hypoxemia in a SLE patient who had pulmonary hypertension patent foramen ovale, a history of recreational drugs use, asthma, and possible antiphospholipid syndrome who presented with acute dyspnea and severe hypoxemia. Her chest x-ray revealed cardiomegaly, increased central pulmonary vessels, decreased lung volumes but no infiltrates or effusions. Severe hypoxemia without pulmonary infiltrates in SLE patients is an unusual presentation; possible explanations include pulmonary emboli, severe pulmonary hypertension, and shrinking lung syndrome.

C-Kit immunoexpression delineates a putative endothelial progenitor cell population in developing human lungs

Expression of c-Kit and its ligand, stem cell factor (SCF), in developing human lung tissue was investigated by immunohistochemistry. Twenty-eight human fetal lungs [age range 13 to 38 gestational wk (GW)] and 12 postnatal lungs (age range 1-79 yr) were evaluated. We identified c-Kit(+) cells in the lung mesenchyme as early as 13 GW. These mesenchymal c-Kit(+) cells in the lung did not express mast cell tryptase or α-smooth muscle actin. However, these cells did express CD34, VEGFR2, and Tie-2, indicating their endothelial lineage. Three-dimensional reconstructions of confocal laser scanning images revealed that c-Kit(+) cells displayed a closed-end tube formation that did not contain hematopoietic cells. From the pseudoglandular phase to the canalicular phase, c-Kit(+) cells appeared to continuously proliferate, to connect with central pulmonary vessels, and finally, to develop the lung capillary plexus. The spatial distribution of c-Kit- and SCF-positive cells was also demonstrated, and these cells were shown to be in close association. Our results suggest that c-Kit expression in early fetal lungs marks a progenitor population that is restricted to endothelial lineage. This study also suggests the potential involvement of c-Kit signaling in lung vascular development.

An unusual case of pulmonary hypertension with multiple osteosclerotic lesions

A 47-year-old married woman with underlying sensorimotor polyneuropathy presented to our emergency department with a 2-week history of fatigue, legs edema and exertional dyspnea. On physical examination, elevated jugular vein pressure, a grade III pansystolic murmur at the left lower sternal border and peripheral edema were noted. Chest radiography revealed cardiomegaly, enlargement of the central pulmonary vessels and bilateral pleural effusions (Figure 1). Electrocardiograms showed right axis deviation. An echocardiogram demonstrated pericardial effusion, severe tricuspid regurgitation, pulmonary hypertension (pulmonary artery pressure was 78 mmHg) and normal left ventricular systolic function (the estimated ejection fraction was 77%). Contrast-enhance chest CT showed no evidence of intraluminal thrombi in the pulmonary arteries but central pulmonary artery dilatation (Figure 2). Chest CT image in a bone window setting showed osteosclerotic lesions in the vertebral body of the thoracic spine (arrow head) and sternum (white arrow), as well as proliferative new bone formation over the right transverse process (black arrow) (Figure 3). She was admitted and initially treated as having pulmonary hypertension with right heart failure. Figure 1. Chest radiograph demonstrates cardiomegaly, enlargement of the central pulmonary vessels and bilateral pleural effusions with more on …

Pulmonary hypertension in sarcoidosis: A review

Pulmonary hypertension (PH) is a well-recognized complication of sarcoidosis. Patients with sarcoidosis-associated PH (SAPH) have poorer functional status and greater supplemental oxygen requirements than sarcoidosis patients without PH, and are more likely to be listed for lung transplantation. PH is an independent risk factor for mortality in sarcoidosis patients awaiting lung transplantation. The pathophysiology of SAPH is complex, with multiple mechanisms contributing to pathogenesis, including the fibrous destruction of the pulmonary vascular bed, extrinsic compression of the central pulmonary vessels and an intrinsic vasculopathy. Recognition of SAPH may be delayed as it can be masked by the clinical picture of underlying pulmonary sarcoidosis, and right heart catheter remains the gold-standard for diagnosis. Management of SAPH is based on reversal of resting hypoxaemia, treatment of comorbidities and treatment of the underlying sarcoidosis. The use of corticosteroids in SAPH is controversial. Specific PH therapy is not routinely recommended in SAPH as there are no successful placebo-controlled trials, although there is limited data to suggest that endothelin receptor antagonists and phosphodiesterase-5 inhibitors may be useful.

Radiofrequency Ablation of Pulmonary Tumors and Normal Lung Tissue in Swine and Rabbits

The purpose of the present study was to examine the following during radiofrequency ablation (RFA): (1) the risk of hemorrhage from intrapulmonary large vessels; (2) the risk of incomplete ablation of pulmonary tumors; and (3) the late effect on lung tissue. A 17-gauge, cool-tip-type radiofrequency electrode was used. The damage to the vessels and bronchi was examined by the injection of a colored silicone rubber, a liquid compound that hardens after injection. To examine the risk of hemorrhage from intrapulmonary large vessels, RFA was conducted at eight sites near the central pulmonary vessels in two swine. To examine the risk of an incomplete ablation for pulmonary tumors, 10 pulmonary nodules were made from a gelatin mixture in another two swine and were treated by RFA. To examine the late effect on lung tissue, RFA was conducted on the peripheral lung in 10 rabbits, and then the ablated regions were examined on days 1, 7, 14, 21, and 28 after RFA. The use of colored silicone rubber enabled us to examine the intrapulmonary vessels and bronchi for opening and leakage. RFA did not damage the large intrapulmonary vessels, even when they were located within the ablated regions. Lung tissue surrounding the gelatin nodules was hardly ablated over its entire circumference. Six of 10 gelatin nodules (60%) showed nonablated areas on the peripheral edges of the nodules. From 21 days after RFA, the ablated rabbit lung formed noninfectious cavities by communicating with the surrounding bronchi. It was improbable for hemorrhage to occur even when RFA was conducted near the large intrapulmonary large vessels. Because an incomplete ablation that left tumor cells at the site of ablation could occur during surgery due to the difficulty of ablating the entire tumor circumference, CT scan-guided RFA would be preferable to a surgical approach for making a safe margin. Cavity formation can occur beginning 21 days after RFA, which should be carefully followed up in a clinical setting to identify infection, especially in immunocompromised patients.

Situs inversus and severe pulmonaryhypertension

A 31-year-old man presented with a 2-year history of progressive exertional dyspnoea and chest pain. He had severe pulmonary hypertension with a mean pulmonary artery pressure of 53 mm Hg. Magnetic resonance imaging (figure, left; T1-weighted 3D echo sequence with contrast), showed the dilated central pulmonary vessels and a persisting left caval vein (arrow) draining into a dilated coronary sinus. Spiral computed tomography (figure, right) showed the liver in midline position, a right-sided hypoplastic spleen (arrow) and the small bowel almost confined to the right abdomen. Abdominal angiography showed complex vascular malformations including bilateral aneurysms of the renal arteries, and an inferior mesenteric vein flowing into the superior mesenteric vein, which drained into the inferior vena cava. In combination with hypoplastic portal and hepatic veins, this anatomy caused a portosystemic shunt with elevated blood ammonia concentrations. This is a rare case with features of heterotaxy syndrome in a young adult, complicated by primary pulmonary hypertension.

Imaging evaluation of suspected pulmonary embolism

Venous thromboembolism (VTE) is a common disorder that is difficult to diagnose clinically but carries significant morbidity and mortality if untreated. Additionally, although demonstrated to be of benefit in cases of proven deep vein thrombosis (DVT) and pulmonary embolism (PE), anticoagulation therapy is not without risk. Because the clinical exam is known to be unreliable for the detection of both DVT and PE, many imaging modalities have been used in the diagnostic imaging algorithm for the detection of VTE, including chest radiography, ventilation/perfusion (V/Q) scintigraphy, pulmonary angiography, and recently, spiral computed tomography (CT) and magnetic resonance imaging (MRI). Chest radiographic findings in acute PE include focal oligemia, vascular enlargement, atelectasis, pleural effusions, and air space opacities representing pulmonary hemorrhage or infarction. The chest radiograph can occasionally be suggestive of PE but is more often nonspecifically abnormal. The main use of the chest radiograph in the evaluation of suspected PE is to exclude entities that may simulate PE and to assist in the interpretation of V/Q scintigraphy. Lower extremity venous compression ultrasonography (CU) is both sensitive and specific for the diagnosis of femoropopliteal DVT, and the value of negative CU results has been established in outcomes studies. However, the reliability of CU for the detection of isolated calf vein thrombosis is not well established, and the clinical significance of such thrombi is debatable. Additional methods such as color and spectral Doppler analysis are also useful in the diagnostic evaluation of DVT but are best considered as adjuncts to the conventional CU examination rather than as primary diagnostic modalities themselves. Compression ultrasonography and Doppler techniques are useful in the evaluation of suspected upper extremity DVT; spectral Doppler waveform analysis is particularly useful to assess for the patency of veins that cannot be directly visualized and compressed with conventional gray-scale sonography. V/Q scintigraphy has been the initial modality obtained in patients suspected of PE for a number of years. Although many studies have investigated the role of V/Q scintigraphy in the evaluation of VTE, the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study has provided the most useful information regarding the utility of V/Q scintigraphy in this setting. A high probability scan interpretation is sufficient justification to institute anticoagulation, and a normal perfusion scan effectively excludes the diagnosis of PE. A normal/near normal scan interpretation also carries a sufficiently low prevalence of angiographically proven PE to withhold anticoagulation. Although the prevalence of PE in the setting of low probability scan interpretations is low and several outcomes studies have demonstrated a benign course in untreated patients with low probability scan results, patients with inadequate cardiopulmonary reserve do not necessarily have good outcomes. Such patients deserve more aggressive evaluation. Patients with intermediate probability scan results have a 20% to 40% prevalence of angiographically proven PE and thus require further investigation. The radionuclide investigation of DVT includes such techniques as radionuclide venography and thrombus-avid scintigraphy. Although these methods have not been as thoroughly evaluated as CU, studies thus far have indicated encouraging results, and further investigations are warranted. Pulmonary angiography has been the gold standard for the diagnosis of PE for decades. Studies have indicated that angiography has probably been underutilized by referring physicians for the evaluation of suspected PE, likely because of the perception of significant morbidity and mortality associated with the procedure. (ABSTRACT TRUNCATED)

The Clinical Usefulness of Spiral CT Angiography in the Diagnosis of Pulmonary Thromboembolism

Background: Pulmonary thromboembolism(PTE) is a life threatening disease that needs early diagnosis. Spiral CT angiography depict thromboemboli in the central pulmonary vessels with greater than 90% sensitivity and specificity, which approaches the results of pulmonary angiography in the Prospective Investigation of Pulmonary Embolism Diagnosis(PIOPED) study. This study was performed to evaluate the findings and the diagnostic value(clinical utility) of the spiral CT angiography with 2D image(multiplanar reformation) and 3D images(Shaded surface display, Minimal intensity projection) in the pulmonary thromboembolism. Methods: We retrospectively analysed spiral CT angiography and pulmonary angiography, lung scan and clinical recordings of 20 patients who had PTE diagnosed by spiral CT angiography(n=19 cases) or pulmonary angiography(n=l case) from September 1997 to August 1998. Among 20 patients who had underwent spiral CT angiography, 14 patients could be performed lung perfusion scan at the same time. We analyzed the vascular and parenchymal change in spiral CT angiogram. Results: Anatomical distribution of PTE was as follows: 1) left lung(n= 103)

Pulmonary Hypertension and Major Surgery

Pulmonary Hypertension and Major Surgery

Cardiopulmonary Bypass as an Adjunct to Pulmonary Surgery

Although performance of concomitant open heart and pulmonary operations has been described, there is general reluctance to perform pulmonary procedures in patients receiving cardiopulmonary bypass (CPB). Reasons for this include fear of excess bleeding caused by systemic heparinization, limited exposure afforded by median sternolomy, and alterations in the immune system caused by CPB that might lead to dissemination of lung cancer or infection. We have used CPB to facilitate operations on the lung in four patients who did not require concomitant cardiac surgery. In each case, lesions involving central pulmonary vessels precluded safe operation by conventional techniques. There were no complications related to the use of CPB. We believe that CPB can be a valuable adjunct in the surgical treatment of selected tumors and vascular malformations that involve large or central pulmonary vessels.

Aorto-pulmonary calcification: An unusual manifestation of idiopathic calcification of infancy evident antenatally

Idiopathic arterial calcification of infancy represents a clinical spectrum involving calcification of large and medium-sized blood vessels with an unknown etiology. Its complications include severe systemic hypertension and cardiomyopathy. A twin infant with a variant of idiopathic arterial calcification was diagnosed antenatally by the detection of hyperechogenicity of the proximal aorta and central pulmonary vessels. The calcification was apparently isolated to these vessels and was associated with polyhydramnios and hypertrophic cardiomyopathy. Because antenatal diagnosis is possible, we suggest that there should be a high index of suspicion for idiopathic arterial calcification when there is sonographic hyperechogenicity of vessel walls, evidence of polyhydramnios, cardiomyopathy, or a family history of idiopathic arterial calcification.

Evaluation of pulmonary blood supply by nuclear magnetic resonance imaging in patients with pulmonary atresia

Nuclear magnetic resonance (NMR) imaging defines the blood pool without the need for contrast medium. Consequently, it may be useful for defining the pulmonary circulation in patients with pulmonary atresia, in whom opacification of these vessels can be problematic.Ten patients with pulmonary atresia were evaluated by gated NMR imaging. The morphology of the right ventricular outflow tract, the size and the course of the central pulmonary vessels and the source of the collateral supply to the lung were assessed. Central pulmonary arteries were identified and measured in 9 of the 10 patients. One patient had no detectable central pulmonary arteries. Angiography confirmed the NMR findings in all but two patients, in whom NMR scanning visualized a main pulmonary artery that was not seen on angiography. Collateral arteries arising from the aorta or the arch vessels, as well as intracardiac malformations and aortic arch anomalies, were identified in all 10 patients. In six patients with palliative surgery, NMR imaging correctly demonstrated all patent shunts.Nuclear magnetic resonance imaging appears to be an effective noninvasive technique for evaluating patients with pulmonary atresia. However, tomographic thickness and spatial resolution are still limiting factors for this technique in infants.