Critical attention is necessary to avoid injury to the conduction system located on the left ventricular side of the interventricular septum near the papillary muscle of the conus. Care is taken to avoid injury to the aortic valve with sutures. Once the repair is complete, the heart is extensively deaired by venting blood through the aortic cardioplegia site, and by infusing Carbon Dioxide into the operative field to displace air. Intraoperative transesophageal echocardiography is used to confirm secure closure of the VSD, normal function of the aortic and tricuspid valves, good ventricular function, and the elimination of all air from the left side of the heart. The sternum, fascia and skin are closed, with potential placement of a local anesthetic infusion catheter under the fascia, to enhance postoperative pain control. Multiple muscular VSDs are a challenge to close, achieving a complete closure can be aided by the use of fluorescein dye. Epidemiology
VSDs are the most common congenital cardiac abnormalities. They are found in 30-60% of all newborns with a congenital heart defect, or about 2-6 per 1000 births. During heart formation, when the heart begins life as a hollow tube, it begins to partition, forming septa. If this does not occur properly it can lead to an opening being left within the ventricular septum. It is debatable whether all those defects are true heart defects, or if some of them are normal phenomena, since most of the trabecular VSDs close spontaneously.
Pannus is an abnormal layer of fibrovascular tissue or granulation tissue. Common sites for pannus formation include over the cornea, over a joint surface (as seen in rheumatoid arthritis), or on a prosthetic heart valve. Pannus may grow in a tumor-like fashion, as in joints where it may erode articular cartilage and bone. In common usage, the term pannus is often used to refer to a panniculus (a hanging flap of tissue). Pannus in rheumatoid arthritis
The term "pannus" is derived from the Latin for "tablecloth". Inflammation and exuberant proliferation of the synovium leads to formation of pannus and destruction of cartilage, bone, tendons, ligaments, and blood vessels. Basically, the hypertrophied synovium is called pannus. Pannus tissue is composed of aggressive macrophage- and fibroblast-like mesenchymal cells, macrophage-like cells and other inflammatory cells that release collagenolytic enzymes. In people suffering from rheumatoid arthritis, pannus tissue eventually forms in the joint affected by the disease, causing loss of bone and cartilage. From Autoimmunity and Disease by Harley Y. Tse and Michail K. Shaw:Chronic stages of the disease typically coincide with the formation of a structure known as a pannus. A pannus is a membrane of granulation tissue composed of mesenchyme- and bone marrow-derived cells. Formation of the pannus stimulates the release of IL-1, platelet-derived growth factor, prostaglandins, and substance P by macrophages, which ultimately cause cartilage destruction and bone erosion. Pannus in ophthalmology
In ophthalmology, pannus refers to the growth of blood vessels into the peripheral cornea. In normal individuals, the cornea is avascular.