Pulmonary Vein Stenosis (PVS) is a condition in which there is an obstruction (blockage) in the blood vessels that bring oxygen-rich blood from the lungs back to the heart.

There are many types of pulmonary vein obstruction. The one in which stenosis occurs due to an abnormal process that thickens and narrows the walls in the veins causing blockage within the lumen of the veins is called intraluminal pulmonary vein stenosis. This type frequently recurs and progresses. As a result, total obstruction or partial loss of flow to a vessel or vessels may occur.

This condition may occur as a complicating feature of complex congenital heart disease or underlying chronic lung disease, but it may also occur in infants with otherwise normal hearts and lungs. This is called Isolated pulmonary vein stenosis; it occurs in early infancy and usually progresses very rapidly. Infants with this disease may seem well for weeks before they develop difficulty breathing and low oxygen levels. They may become quite ill quickly. The effects of the disease vary in children with co-existing congenital heart defects.

Symptoms

Symptoms include jugular venous distention, cyanosis (usually visible in the nailbeds), right ventricular hypertrophy and general symptoms of lowered oxygenation of the blood.

Causes

The cause of the disease is still un-known however the mechanism of progressive intraluminal pulmonary vein stenosis is thought to result from uncontrolled growth of connective tissue cells, which causes the blockage in the pulmonary veins. The cells are thought to be myofibroblast-like. These cells are normally in our bodies and function in wound healing.

The cells are also known to grow abnormally in several different disease processes in both children and adults. It appears that this cell type plays a role in the development of pulmonary vein stenosis. Current treatment focuses upon removal of the obstruction and prevention of progression and recurrence of this abnormal cell growth.

To establish a diagnosis of progressive pulmonary vein stenosis, a series of tests are performed.
Tests include:

  • Echocardiogram (echo) — A procedure that evaluates the structure and function of the heart by using sound waves, recorded on an electronic sensor, that produce a moving picture of the heart and heart valves. This test estimates pressures within the heart and lungs and measures bloodflow through the pulmonary veins back to the heart looking for evidence of vein obstruction (blockage).
  • Lung Scan — A test that uses an intravenous (IV) tube and radioactive isotope to obtain information about how much blood flow goes to each part of the lung.
  • CT Scan — A non-invasive type of X-ray test that provides detailed images and information about blood flow through the lungs, as well as information about the appearance of the lung tissue.
  • Cardiac Catheterization — A procedure that gives very detailed information about the structures inside the heart. Under sedation, a small, thin, flexible tube (catheter) is inserted into a blood vessel in the groin and guided to the inside of the heart. Blood pressure and oxygen measurements are taken in the heart, as well as in the pulmonary artery and aorta. Contrast dye may be injected to more clearly see the structures inside the heart or lungs.

Standard Treatments

The standard treatments for this condition are designed to improve blood flow from the lungs back to the heart.

  • Open-heart surgery may be preformed to widen the narrowed veins and improve blood flow from the lungs back to the heart.
  • Cardiac catheterization with balloon dilation may be performed to try to stretch the vessel. Some patients benefit from placement of a stents (a mesh tube used to prop open the vessel).
  • Lung transplantation may be done to replace the lungs and the pulmonary veins. Patients require lifelong immunosuppression (medications to prevent rejection after organ transplantation).

Source: Childrens Hospital Boston