Who Is At Risk For PAPVR & Is There A Blood Test For It?

Partial Anomalous Pulmonary Venous Return (PAPVR) is a rare disorder and is seen only in 0.4-0.7% of postmortem examinations(1).

PAPVR is usually associated with other heart abnormalities(1).

Who Is At Risk For PAPVR?

Since PAPVR is a rare condition, it is rarely detected clinically; therefore, most of the cases are detected during autopsy with an estimated frequency of 0.4-0.7%. The incidence of the disease is also higher in females than in males. The defect is present from birth, but it is usually clinically diagnosed in middle age or even during postmortem. PAPVR is also found in 10% of the patients with an established diagnosis of the atrial septal defect (ASD). It can also be found in people with other congenital syndromes, such as Turner’s syndrome (missing of the X chromosome). Although, there is no known cause of the anomaly and has not been linked to any teratogen (drugs or infection) or associated family history.(1), (3).

Initially, PAPVR is asymptomatic in children, and symptoms are noted only in older patients due to volume overload on the right side of the heart obstructive disease of the lung vessels. The severity of the disease depends on the number of anomalous veins and if only a single vein is defective, it usually does not produce any symptoms. Adults may present with dyspnea, palpitations, cardiac arrhythmias, chest pain, hemoptysis (bloody sputum while coughing), pulmonary vascular disease (pulmonary hypertension), and peripheral edema (due to right-sided heart failure). Children may present with intolerance to exercise (when >50% of pulmonary veins are anomalous) or cardiac murmur(1).

Is There A Blood Test For PAPVR?

PAPVR is not diagnosed with a blood test and its diagnosis is mostly based on imaging studies of the heart. Chest X-ray may show cardiomegaly (enlargement of the heart), main pulmonary artery dilatation, and increase in the pulmonary arterial vascular markings or it may be grossly normal. Echocardiography is the study of choice for diagnosing PAPVR in children and in adults it may help with the diagnosis, which may show right ventricular dilatation. MRI is the study of choice for adults for further confirmation of PAPVR. Contrast-enhanced CT may also be an alternative in older children and adults. Electrocardiogram may reveal right atrial and ventricular dilatation(1).

Cardiac catheterization may be done in some cases but is rarely needed. The oxygen saturation level of the right atrium compared to superior vena cava is increased in PAPVR and may suggest the definitive diagnosis, provided the atrial septal defect is ruled out. Definitive anatomic diagnosis may be carried out with selective right and left pulmonary artery angiography. Cardiac catheterization is accompanied by certain complications, which include bleeding at the site of vascular entry, infection, arrhythmias, and decreased pulse beyond the site of arterial entry(1).

PAPVR is an uncommon birth disorder affecting the heart. Normally, the left atrium is connected to the pulmonary vein, but in PAPVR some of the pulmonary veins drain the blood to the right atrium. This separates PAPVR from TAPVR (Total Anomalous Pulmonary Venous Return) found exclusively in newborns in which all or most pulmonary venous veins connect to the right side of the heart. The abnormality is found in only one pulmonary vein and it is a very rare finding that all the pulmonary veins from one lung are abnormal(1).

PAPVR can have a lot of variations. However, in 80-90% of the cases, PAPVR is right-sided affecting the right side of the lungs and drains into superior vena cava (SVC) that is mostly accompanied by sinus venosus atrial septal defect (ASD). It can also drain into the right atrium or the inferior vena cava (IVC). When the anomalous pulmonary vein drains into the IVC along with the hypoplasia of the right lung and right pulmonary artery along with shifting of the heart to that side (dextroposition), it is termed as Scimitar syndrome(2).


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