Atresia of the bilateral pulmonary veins: a rare and dismal anomaly identified on cardiac CT

Multimodality diagnostic imaging for anomalous pulmonary venous connections: a pictorial essay

Anomalous pulmonary venous connections represent a heterogeneous group of congenital heart diseases in which a part or all pulmonary venous flow drains directly or indirectly into the right atrium. Clinically, anomalous pulmonary venous connections may be silent or have variable consequences, including neonatal cyanosis, volume overload and pulmonary arterial hypertension due to the left-to-right shunt. Anomalous pulmonary venous connections are frequently associated with other congenital cardiac defects and their accurate diagnosis is crucial for treatment planning. Therefore, multimodality diagnostic imaging, comprising a combination (but not all) of echocardiography, cardiac catheterization, cardiothoracic computed tomography and cardiac magnetic resonance imaging, helps identify potential blind spots relevant to each imaging modality before treatment and achieve optimal management and monitoring. For the same reasons, diagnostic imaging evaluation using a multimodality fashion should be used after treatment. Finally, those interpreting the images should be familiar with the various surgical approaches used to repair anomalous pulmonary venous connections and the common postoperative complications.

Computed tomography of pulmonary veins: review of congenital and acquired pathologies

Newer-generation CT scanners with ultrawide detectors or dual sources offer millisecond image acquisition times and significantly decreased radiation doses compared to historical cardiac CT and CT angiography. This technology is capable of nearly freezing cardiac and respiratory motion. As a result, CT is increasingly used for diagnosing and monitoring cardiac and vascular abnormalities in the pediatric population. CT is particularly useful in the setting of pulmonary vein evaluation because it offers evaluation of the entire pulmonary venous system and lung parenchyma. In this article we review a spectrum of congenital and acquired pulmonary venous abnormalities, including potential etiologies, CT imaging findings and important factors of preoperative planning. In addition, we discuss optimization of CT techniques for evaluating the pulmonary veins.

Unilateral pulmonary vein atresia: Literature overview and case report

The unilateral absence of the pulmonary vein, known as pulmonary vein atresia, is a rare type of unilateral pulmonary venous hypoplasia caused by the congenital atrophy of the long pulmonary vein segments in one lung. The involved lung may be normal in size or present with hypoplasia and is often characterized by increased interstitial attenuation and interlobular septal thickening due to venous stasis, edema, and fibrosis. Pulmonary angiography often reveals a reduced size for the lateral pulmonary artery, peripherally sparse pulmonary vessels, contrast stasis, and the inability to visualize pulmonary veins. Symptoms include coughing up blood and infection. We present the clinical case of a patient who was initially diagnosed with recurrent hemoptysis due to pulmonary tuberculosis, followed by unsuccessful treatment. Imaging by 64-slice computed tomography with contrast injection using multiplanar reformation and volume rendering techniques allowed this case to be definitively diagnosed. This report emphasizes the epidemiological factors and clinical and imaging features of unilateral pulmonary vein atresia to prevent confusion and facilitate proper diagnosis in similar cases.

Pediatric Cardiothoracic CT Guideline Provided by the Asian Society of Cardiovascular Imaging Congenital Heart Disease Study Group: Part 2. Contemporary Clinical Applications

The use of pediatric cardiothoracic CT for congenital heart disease (CHD) was traditionally limited to the morphologic evaluation of the extracardiac thoracic vessels, lungs, and airways. Currently, the applications of CT have increased, owing to technological advancements in hardware and software as well as several dose-reduction measures. In the previously published part 1 of the guideline by the Asian Society of Cardiovascular Imaging Congenital Heart Disease Study Group, we reviewed the prerequisite technical knowledge for clinical applications in a user-friendly and vendor-specific manner. Herein, we present the second part of our guideline on contemporary clinical applications of pediatric cardiothoracic CT for CHD based on the consensus of experts from the Asian Society of Cardiovascular Imaging CHD Study Group. This guideline describes up-to-date clinical applications effectively in a systematic fashion.

Unilateral pulmonary vein atresia presenting with recurrent haemoptysis in a child: a case report

BACKGROUND

Haemoptysis is an uncommon presenting symptom in children and is usually caused by acute lower respiratory tract infection or foreign body aspiration. We report a rare case of right unilateral pulmonary vein atresia (PVA) as the underlying aetiology of recurrent haemoptysis in a child.

CASE PRESENTATION

A 4 years old girl presented with history of recurrent haemoptysis. Bronchoscopic evaluation excluded a foreign body aspiration but revealed right bronchial mucosal hyperaemia and varices. Diagnosis of right unilateral PVA was suspected on transthoracic echocardiography which demonstrated hypoplastic right pulmonary artery and non-visualization of right pulmonary veins. Final diagnosis was confirmed on cardiac CT angiography. A conservative treatment approach was opted with consideration for pneumonectomy in future when she is older.

CONCLUSION

Rarer causes should be considered when investigating for recurrent haemoptysis in children. Bronchoscopy and cardiac imaging are useful tools to establish the diagnosis of unilateral PVA in our case.

Asian consortium on radiation dose of pediatric cardiac CT (ASCI-REDCARD)

BACKGROUND

With incremental utilization of pediatric cardiac CT in congenital heart disease, it is imperative to define its current radiation dose levels in clinical practice in order to help imagers optimize CT protocols, particularly in Asia and other developing countries where CT physicists are not readily available.

OBJECTIVE

To evaluate current radiation dose levels and influencing factors in cardiac CT in children with congenital heart disease in Asia by conducting a retrospective multi-center, multi-vendor study.

MATERIALS AND METHODS

We included 1,043 pediatric cardiac CT examinations performed in 8 centers between January 2014 and December 2014 to evaluate congenital heart disease. In five weight groups, we calculated radiation dose metrics including volume CT dose index, size-specific dose estimate, dose-length product and effective dose. Age at CT exam, gender, tube voltage, scan mode, CT indication and image reconstruction algorithm were analyzed to learn whether they influenced CT radiation dose.

RESULTS

Volume CT dose index, size-specific dose estimate, dose-length product and effective dose of pediatric cardiac CT showed variations in the range of 4.3-23.8 mGy, 4.9-17.6 mGy, 55.8-501.3 mGy∙cm and 1.5-3.2 mSv, respectively, within five weight groups. Gender, tube voltage, scan mode and cardiac function assessment significantly influenced CT radiation dose.

CONCLUSION

This multi-center, multi-vendor study demonstrated variations in radiation dose metrics of pediatric cardiac CT reflecting current practice in Asia. Gender, tube voltage, scan mode and cardiac function assessment should be considered as essential radiation dose-influencing factors in developing optimal pediatric cardiac CT protocols.

Venovenous ECMO Support in an Infant With Single Ventricle Physiology and Catastrophic Pulmonary Venous Abnormalities

Extracorporeal membrane oxygenation (ECMO) is an accepted treatment modality for life support refractory to conventional efforts in neonates with complex congenital heart lesions. Cannulation for ECMO can be accomplished by venovenous (VV) access where patients receive primarily respiratory support or venoarterial (VA) access which provides complete cardiopulmonary support. VV ECMO delivered by a single-vessel cannulation with a dual-chamber venous cannula allows for respiratory support while the patient remains dependent upon intrinsic cardiac function to support hemodynamics. We present a case of support of a newborn with single ventricle physiology and intraparenchymal near-atresia of the pulmonary veins using VV ECMO.