Failure of the vessel to close can lead to serious illness Scientists have made a breakthrough in understanding why a foetal blood vessel can fail to close shortly after birth, causing serious health problems. If the ductus arteriosus fails to close babies develop high blood pressure in the lungs and heart failure. A German team showed that platelets, cells in the blood which form clots, play a key role in closing the vessel. The study, by researchers at Munich's Technischen University, appears in the journal Nature Medicine. The ductus arteriosus is a short vessel which connects the pulmonary artery to the aorta, allowing most of the blood from the right ventricle of the heart to bypass the foetus's fluid-filled lungs. A better understanding of how the ductus arteriosus closes just after birth could help the treatment of very vulnerable babies, and potentially save lives

Professor Jeremy Pearson

British Heart Foundation This protects the lungs from being overworked and allows the left ventricle of the heart to strengthen. However, once development is complete, the vessel's work is done and it usually closes in the hours after birth. But how this process takes place has been unclear and sometimes it does not happen, causing a condition known as patent ductus arteriosus. This is a particular risk in premature babies with a low birth weight. If left uncorrected this can lead to a build up of pressure in the blood vessels of the lung, which can trigger shortness of breath and dizziness. Ultimately, it can lead to irregular heart rhythms and congestive heart failure. Working on mice, the Munich team found that platelets congregate at the ductus arteriosus during closure, promoting the formation of a clot as the vessel contracts. They showed that in mice with defective platelet function, the ductus arteriosus failed to close. This resulted in a condition similar to that found in the human disease: increased blood flow in the lung and excessive growth of the right ventricle of the heart. Transfusion possibility The researchers also showed, in a clinical study in premature babies, that not having enough platelets in the blood was associated with a failure of the ductus arteriosus to close. Lead researcher Dr Steffen Massberg said: "Our study might might lead to a change of the current treatment strategies to prevent failure of ductus arteriosus closure, particularly in preterm newborns with low platelet counts. "It is conceivable that transfusion of platelets reduces the risk of ductus arteriosus patency (lack of closure) in preterm newborns with low platelet count." Professor Jeremy Pearson, of the British Heart Foundation, said: "This breakthrough is really promising as a better understanding of how the ductus arteriosus closes just after birth could help the treatment of very vulnerable babies, and potentially save lives."



Bookmark with: Delicious

Digg

reddit

Facebook

StumbleUpon What are these? E-mail this to a friend Printable version