Intrapulmonary segment in anomalous pulmonary venous connection. Resemblance to scimitar syndrome

Anomalous Pulmonary Venous Connection With an Intraparenchymal Course

An intraparenchymal course of the pulmonary venous pathway within one lung in anomalous pulmonary venous connection is a rare and poorly recognized variation. We report three new cases and summarize the remaining 19 known cases of this infrequent anomaly. We expect that this review will call attention to this unusual pattern of pulmonary venous drainage and enhance prospective diagnosis.

Atypical pulmonary venous drainage pathway associated with infracardiac total anomalous pulmonary venous connection: report of a case

Darling's classification for total anomalous pulmonary venous connection (TAPVC) is based only on the level of the site of drainage of the anomalous pulmonary veins (PVs) to the systemic venous circulation. Although it is a clinically useful classification, atypical course of the PVs is occasionally encountered as well. We report a case of infracardiac-type TAPVC in which the left upper PV traversed the posterior mediastinum and merged into the right PVs at the right hilum. The combined vein coursed medially and caudally, meeting the left lower PVs, and finally penetrated the diaphragm; the pulmonary venous drainage formed a shape of "C." Despite definitive diagnosis according to Darling's classification, sometimes atypical course of the PVs do exist. Echocardiography may not be adequate for atypical cases. Contrast-enhanced computed tomography may be recommended in stable patients where an atypical course is suspected.

Intrapulmonary vertical vein associated with an infracardiac type of totally anomalous pulmonary venous connection

We encountered 2 cases of a very rare type of anomalous pulmonary venous drainage associated with infracardiac type of total anomalous pulmonary venous connection. The pulmonary vein from the entire left lung traversed the posterior mediastinum and joined the right pulmonary vein at the hilum. Furthermore, a large drainage vein coursed caudally through the pulmonary parenchyma and penetrated the diaphragm. The morphology of the pulmonary venous system could not be delineated by preoperative echocardiography. It should be noted that the vertical vein of this variant cannot be found, even if the posterior mediastinum is extensively dissected during operation, and exploration of the pleural cavity is necessary.

Incidental meandering right pulmonary vein, literature review and proposed nomenclature revision

We report a case of an anomalous pulmonary vein on chest X-ray resembling a scimitar sign in an 80-year-old female undergoing investigation of syncope. Multislice computed tomography (CT) with multiplanar reformatting and maximum intensity projections demonstrated an aberrant right inferior pulmonary vein coursing inferomedially towards the diaphragm before turning superiorly and draining normally into the left atrium. The diagnosis of an incidental meandering right pulmonary vein was established. The case is used to review the literature on this rare pulmonary anomaly, including pathogenesis, its relationship with scimitar syndrome and scimitar variant, and diagnosis, with an emphasis on the role modern CT techniques can play in non-invasive diagnosis. A revision to the nomenclature of pulmonary vascular anomalies is proposed to help reduce confusion in the literature.

Acquired anomalous intrapulmonary venous connection secondary to pulmonary venous stenosis

An unusual case of acquired development of anomalous intrapulmonary venous connection with pulmonary venous stenosis is presented. Appearances on a chest radiograph resembled the "scimitar" sign in a patient with previous surgery for partial anomalous pulmonary venous return. Spiral CT and pulmonary arteriography showed stenosis of the right upper pulmonary vein and an anomalous intrapulmonary venous connection between the right upper pulmonary vein and the right lower pulmonary vein. We consider the slow progression of pulmonary vein stenosis led to anomalous intrapulmonary venous connection as an intrapulmonary collateral.

Anomalous pulmonary venous pathway traversing pulmonary parenchyma. Diagnosis and implication

STUDY OBJECTIVES

To describe four patients having total anomalous pulmonary venous connection with an intrapulmonary vertical vein, rendering difficulty in diagnosis and surgery.

SETTING

a tertiary referral center.

PATIENTS AND METHODS

By reviewing medical records, 4 of 25 patients with right atrial isomerism and total anomalous pulmonary venous connection were identified to have an intrapulmonary vertical vein. All four patients underwent echocardiography, catheterization, and angiography. One underwent MRI. Two underwent open-heart surgery and one received a modified Blalock-Taussig shunt.

RESULTS

Right atrial isomerism was present in all four patients. On chest x-ray films, an abnormal shadow resembling scimitar syndrome was seen in two patients. Imaging the vertical vein was unsuccessful with an echocardiogram in all four patients. The intrapulmonary course of the vertical vein was depicted with a pulmonary venogram in two patients and with magnetic resonance in one patient. The intrapulmonary segment remained undetected until autopsy in one patient. All four patients died. At autopsy, the pulmonary venous confluence was hypoplastic in all four hearts. The vertical vein was buried in pulmonary parenchyma and drained to superior vena cava with significant obstruction.

CONCLUSION

In the presence of right atrial isomerism and total anomalous pulmonary venous connection, there may be an intrapulmonary pulmonary venous connection that may be obstructed. Anastomosing the pulmonary venous confluence to the atrium may be difficult because of hypoplasia of the pulmonary venous confluence.

A case of an anomalous pulmonary vein of the right middle lobe

A case is reported in which the abnormal course of a pulmonary vein was suggested by computed tomography and confirmed by digital subtraction angiography. The vein drained blood from the right middle lobe into the apical pulmonary vein. This abnormality was probably due to abnormal segmentation of the right lung. Comparable cases have been reported in the literature. It is important to distinguish these benign lesions from more complex malformations because of the therapeutic and prognostic implications. The radiologic findings of this case and a systematic overview of pulmonary vein abnormalities is provided.

Unusual form of total anomalous pulmonary venous connection with double drainage

A patient with complex congenital heart disease was diagnosed by two-dimensional echocardiography. Total anomalous pulmonary venous connection (TAPVC) was suspected because of the results of two-dimensional echocardiography, but the exact anatomy was delineated by cineangiocardiography as an unusual form of TAPVC with double drainage or connections to the left superior vena cava at nearly the same level. The clinical implications and possible embryogenesis for such a condition are discussed.

Successful repair of a rare type of total anomalous pulmonary venous drainage

This report describes a 2-month-old female infant with a rare supracardiac type of total anomalous pulmonary venous drainage. The intrapulmonary drainage of the pulmonary veins was into the right lung from the left lung. The anomaly was successfully repaired by atriocavoplasty.

Anomalous unilateral single pulmonary vein mimicking partial anomalous pulmonary venous return

We report a case in which the clinical findings of a partial anomalous pulmonary venous return were present but with termination of the anomalous pulmonary vein into the left atrium. There was hypoplasia of the right lung, dextroposition of the heart, and a loop-like vascular density in the right lung field. Cardiac catheterization revealed no shunt, and on pulmonary angiograms, a large common right pulmonary vein draining the entire right lung and entering the left atrium by way of a single orifice. Possible embryologic explanations include atresia of the right inferior pulmonary vein and persistence of the ipsilateral superior pulmonary vein.

Rare type of intrapulmonary drainage of one lung by the other with total anomalous pulmonary venous return

A rare form of obstructed total anomalous pulmonary venous drainage is presented. A neonate with asplenia, pulmonary atresia and complex congenital heart disease also had drainage of the left lung forming a venous confluence that proceeded in an intrapulmonary fashion through the right lung. A hypoplastic pulmonary venous channel then emerged from the right upper lobe leading to the superior vena cava. Pulmonary venous obstruction was suspected on initial plain chest X-ray examination and on angiography, which revealed the pulmonary artery to be larger than anticipated. Administration of prostaglandin E1 may allow augmentation of pulmonary blood flow and angiographic definition of this association in infants with asplenia complex.

Cor triatriatum: study of 20 cases

Twenty cases of cor triatriatum are reported. The diagnosis was confirmed by necropsy in 16 cases and at the time of operation in 4. The lesion occurred as an isolated anomaly in 7 cases; in 13, other associated cardiac anomalies were present. Three anatomic types of cor triatriatum were identified in the cases studied at necropsy: diaphragmatic (10 cases), hourglass (3) and tubular (3). The diaphragmatic type was also present in all four cases in which the diagnosis was confirmed at operation. Associated anomalies were found in five cases of the diaphragmatic type and in each case of the hourglass of tubular types. In isolated cor triatriatum the clinical findings were characteristic of pulmonary venous and arterial hypertension. In two cases, one with a communication between the right atrium and the accessory left atrial chamber and one with partial anomalous pulmonary venous connection associated with cor triatriatum, the clinical findings suggested a large left to right shunt with pulmonary arterial hypertension. The clinical findings varied in the cases with associated anomalies, and it was difficult to determine the cause of disturbance of the circulation.