OBJECTIVE: To assess perfusion patterns on a dual-energy pulmonary CT angiography (DECTA) of pulmonary hypertension (PHT) with variable causes and to assess whether the extent of perfusion defect can be used in the severity assessment of PHT. MATERIALS AND METHODS: Between March 2007 and February 2011, DECTA scans of 62 consecutive patients (24 men, 38 women; mean age, 58.5 +/- 17.3 [standard deviation] years; range, 19-87 years) with PHT were retrospectively included with following inclusion criteria; 1) absence of acute pulmonary thromboembolism, 2) maximal velocity of tricuspid regurgitation jet (TR Vmax) above 3 m/s on echocardiography performed within one week of the DECTA study. Perfusion patterns of iodine map were divided into normal (NL), diffuse heterogeneously decreased (DH), multifocal geographic and multiple peripheral wedging patterns. The extent of perfusion defects (PD), the diameter of main pulmonary artery (MPA) and the ratio of ascending aorta diameter/MPA (aortopulmonary ratio, APR) were measured. Pearson correlation analysis was performed between TR Vmax on echocardiography and CT imaging parameters. RESULTS: Common perfusion patterns of primary PHT were DH (n = 15) and NL (n = 12). The perfusion patterns of secondary PHT were variable. On the correlation analysis, in primary PHT, TR Vmax significantly correlated with PD, MPA and APR (r = 0.52, r = 0.40, r = -0.50, respectively, all p < 0.05). In secondary PHT, TR Vmax significantly correlated with PD and MPA (r = 0.38, r = 0.53, respectively, all p < 0.05). CONCLUSION: Different perfusion patterns are observed on DECTA of PHT according to the causes. PD and MPA are significantly correlated with the TR Vmax.
Adult ; Aged ; Aged, 80 and over ; Aorta/physiopathology ; Aortography ; Female ; Humans ; Hypertension, Pulmonary/physiopathology/*radiography ; Male ; Middle Aged ; Pulmonary Artery/physiopathology/*radiography ; Pulmonary Circulation/physiology ; Retrospective Studies ; Tomography, X-Ray Computed/*methods ; Tricuspid Valve Insufficiency/physiopathology/radiography ; Young Adult

The assessment of the accuracy of Electron Beam Computed Tomography (EBCT) for the follow-up of pulmonary vascular system after the shunt operation in cyanotic congenital heart diseases was purpose of the study. The study group consists of 16 consecutive patients with cyanotic congenital heart disease who had Blalock-Taussig (BT) shunt (n=7), bi- directional cavo-pulmonary shunt (BCPS, n=7) and unifocalization (n=2). EBT images were obtained on systolic phase under EKG gating and after intravenous administration of contrast agent. We evaluated the shunt patency, anatomy of intrapericardial pulmonary artery, parenchymal pulmonary vessels and background lung attenuation for the pulmonary blood flow, and the presence of systemic arterial and venous collaterals. Angiography (n=12) and echocardiography (n=16) were used as the gold standards. EBCT was consistent with angiogram in detecting the shunt patency and in depicting the anatomy of the intrapericardial pulmonary artery. Occlusion of the BT shunts was not detected in 2 patients by echocardiography. Diffuse or focally decreased pulmonary flow on EBCT in 8 patients was consistent with the pulmonary hemodynamics pattern revealed by cardiac catheterization. Uneven attenuation between lobes was related with multifocal supply of pulmonary flow or occlusion of lobar pulmonary arteries. Systemic collateral arteries were observed in 5 at the corresponding site of the decreased pulmonary flow. Systemic venous collaterals seen in all patients following BCPS were eventually draining to the inferior vena cava in 5 and to the left atrium in 2. EBCT provided accurate information of the pulmonary vascular system after shunt and has unique advantage over echocardiography in assessing patency of BT shunt or unifocalization tubes within the pleural space, the estimation of regional difference in pulmonary hemodynamics, and the detection of systemic collateral vessels. Therefore EBCT may provide useful information about the timing of definitive correction and the need for a second shunt or an interventional procedure prior to total repair.
Child ; Child, Preschool ; Collateral Circulation ; Female ; Heart Defects, Congenital/physiopathology/*radiography/*surgery ; Human ; Infant ; Male ; Pulmonary Artery/*surgery ; Pulmonary Circulation ; Subclavian Artery/*surgery ; *Tomography, X-Ray Computed

BACKGROUNDPulmonary artery sling (PAS) is a rare congenital heart anomaly and may cause unexplained respiratory symptoms in infants. Since the non-specific respiratory symptoms of PAS may lead to misdiagnosis, the aim of this study was to clarify the clinical and imaging features of this disease for timely diagnosis and treatment.

METHODSClinical histories, physical examinations and imaging studies were retrospectively evaluated in nine infants with PAS. Chest X-ray, echocardiography and contrast-enhanced computed tomography (CT) with 3-dimensional reconstructions were performed in all patients and three of them received surgical treatment.

RESULTSNine cases included six males and three females with a mean age of (4.3 ± 2.8) months ranging from 2 to 11 months old. All patients had respiratory symptoms including recurrent cough, stridor and wheezing. The onset of symptoms was within 3 months in all cases and three children had symptoms only a few days after birth. The chest X-ray showed pneumonia in all cases. Contrast-enhanced CT showed the tracheal compression at different lengths in every case. The echocardiograph findings of PAS were anomalous origins of the left pulmonary artery from the posterior aspect of the right pulmonary artery. Of the 9 cases, 8 cases were diagnosed correctly by echocardiography. Of the complicated abnormalities, there were one with secundum atrial septal defect, one with patent foramen ovale and three with persistent left superior vena cava. None of them were complicated with significant blood dynamic changes.

CONCLUSIONSInfants with recurrent respiratory symptoms such as chronic cough, stridor and wheezing, should be examined for the possible presence of congenital pulmonary artery sling. As a noninvasive technique, echocardiography is very helpful and should be the first-choice modality for the diagnosis of pulmonary artery sling. Contrast-enhanced CT, clearly demonstrating the anatomy of pulmonary artery sling and the position and extent of trachea compression, is necessary for the final diagnosis and pre-operation evaluation.

Echocardiography ; Female ; Heart Defects, Congenital ; diagnosis ; diagnostic imaging ; physiopathology ; Hemodynamics ; physiology ; Humans ; Infant ; Male ; Pulmonary Artery ; abnormalities ; diagnostic imaging ; physiopathology ; Radiography