The most common form is where the left upper pulmonary vein connects to the left brachiocephalic vein into the superior vena cava. Another type is where the right upper pulmonary veins connect directly into the superior vena cava, which is commonly associated with other left to right shunts, including atrial septal and superior sinus venosus defects. Another unique variant of PAPVC is Scimitar syndrome, in which part or all of the right pulmonary veins connect to the inferior vena cava through the diaphragm. The right lung is often hypoplastic and/or has anomalous bronchial or arterial anatomy in addition to the PAPVC. The ultimate management of PAPVC is usually surgical correction, but unlike TAPVC, this does not always happen shortly after birth due to delayed diagnosis or mild symptoms. Advanced imaging in diagnosis of PAPVC is usually requested in the setting in which a TTE shows right-sided cardiac chamber dilation with unclear delineation of the pulmonary venous anatomy. The role of imaging in PAPVC management is to confirm the diagnosis, define the surgical anatomy, and quantify the shunt to help decide on need for and timing of intervention. Arteriography Coronary with Ventriculography Cardiac catheterization was traditionally the imaging modality used for the diagnosis of TAPVC and PAPVC; however, it has mostly been replaced by less invasive modalities [60]. Cardiac catheterization can be used to demonstrate the anatomy and quantify the degree of shunting using oximetry. However, cardiac catheterization has been shown by some studies to be less accurate in the setting of PAPVC [61]. Occasionally, simultaneous depiction of systemic and pulmonary vascular systems may be difficult in catheter angiography due to overlapping views of adjacent vascular structures. Moreover, it carries high risk of mortality in obstructive TAPVC.
Congenital or Acquired Heart Disease. The most common form is where the left upper pulmonary vein connects to the left brachiocephalic vein into the superior vena cava. Another type is where the right upper pulmonary veins connect directly into the superior vena cava, which is commonly associated with other left to right shunts, including atrial septal and superior sinus venosus defects. Another unique variant of PAPVC is Scimitar syndrome, in which part or all of the right pulmonary veins connect to the inferior vena cava through the diaphragm. The right lung is often hypoplastic and/or has anomalous bronchial or arterial anatomy in addition to the PAPVC. The ultimate management of PAPVC is usually surgical correction, but unlike TAPVC, this does not always happen shortly after birth due to delayed diagnosis or mild symptoms. Advanced imaging in diagnosis of PAPVC is usually requested in the setting in which a TTE shows right-sided cardiac chamber dilation with unclear delineation of the pulmonary venous anatomy. The role of imaging in PAPVC management is to confirm the diagnosis, define the surgical anatomy, and quantify the shunt to help decide on need for and timing of intervention. Arteriography Coronary with Ventriculography Cardiac catheterization was traditionally the imaging modality used for the diagnosis of TAPVC and PAPVC; however, it has mostly been replaced by less invasive modalities [60]. Cardiac catheterization can be used to demonstrate the anatomy and quantify the degree of shunting using oximetry. However, cardiac catheterization has been shown by some studies to be less accurate in the setting of PAPVC [61]. Occasionally, simultaneous depiction of systemic and pulmonary vascular systems may be difficult in catheter angiography due to overlapping views of adjacent vascular structures. Moreover, it carries high risk of mortality in obstructive TAPVC.