The oxygen-rich ("red") blood then returns to the left heart, via the pulmonary veins, and is pumped through the aorta to the rest of the body, including the heart muscle itself.With d-TGA, deoxygenated blood from the right heart is pumped immediately through the aorta and circulated to the body and the heart itself, bypassing the lungs altogether, while the left heart pumps oxygenated blood continuously back into the lungs through the pulmonary artery. In effect, two separate "circular" (parallel) circulatory systems are created, rather than the "figure 8" (in series) circulation of a normal cardio-pulmonary system. Variations and similar defects
Arterial spatial relationships
Differences in the shape of the atrial septum and/or ventricular outflow tracts affect the relative positions of the aorta and pulmonary artery. In the majority of d-TGA cases, the aorta is anterior and to the right of the pulmonary artery, but it can also be directly anterior or anterior and to the left. The aorta and pulmonary artery can also be side by side, with aorta on either side. This is a less common variant, and with this arrangement, an unusual coronary artery pattern is common. There are also some cases with aorta to the right and posterior to the pulmonary artery. Simple and complex d-TGA
d-TGA is often accompanied by other heart defects, the most common type being intracardiac shunts such as atrial septal defect (ASD) including patent foramen ovale (PFO), ventricular septal defect (VSD), and patent ductus arteriosus (PDA). Stenosis of valves or vessels may also be present.
During an infertility work-up a hysterosalpingogram, an X-ray procedure that uses a contrast agent to image the Fallopian tubes, shows the retort-like shape of the distended tubes and the absence of spillage of the dye into the peritoneum. If, however, there is a tubal occlusion at the utero-tubal junction, a hydrosalpinx may go undetected. When a hydrosalpinx is detected by a hysterosalpingogram it is prudent to administer antibiotics to reduce the risk of reactivation of an inflammatory process. When laparoscopy is performed, the surgeon may note the distended tubes, identify the occlusion, and may also find associated adhesions affecting the pelvic organs. Laparoscopy not only allows for the diagnosis of hydrosalpinx, but also presents a platform for intervention (see management). Prevention
As pelvic inflammatory disease is the major cause of hydrosalpinx formation, steps to reduce sexually transmitted disease will reduce incidence of hydrosalpinx. Also, as hydrosalpinx is a sequel to a pelvic infection, adequate and early antibiotic treatment of a pelvic infection is called for. Management
For most of the past century patients with tubal infertility due to hydrosalpinx underwent tubal corrective surgery to open up the distally occluded end of the tubes (salpingostomy) and remove adhesions (adhesiolysis). Unfortunately, pregnancy rates tended to be low as the infection process often had permanently damaged the tubes, and in many cases hydrosalpinges and adhesions formed again. Further, ectopic pregnancy is a typical complication. Surgical interventions can be done by laparotomy or laparoscopy.