Eisenmengers Complex is the term used to describe the resultant effects of prolonged pulmonary hypertension in patients with uncorrected congenital heart defects, which eventually results in a reversal of the shunting of blood within the heart (see Pulmonary Hypertension Topic Note), so that it goes from right to left.
The effect of this right to left shunting is to pump blood from the right side of the heart which takes blood to the lungs, through the septal defect(s) (hole or holes in the central heart wall) and into the left side of the heart which takes blood to the body. Thus a proportion of blood bypasses the lungs and is not oxygenated, so the level of oxygen (saturation) in the blood decreases and the patient is cyanosed (blue).
In order to compensate for the low oxygen levels (saturation) in the blood, the body may produce too many red blood cells (the cells which take the oxygen around the body). This excess of red blood cells is called Polycythemia. It causes a thickening of the blood, headaches, chest, joint and muscle pain. It can also cause visual disturbance and thrombosis (clots of blood) and embolism (moving blood clots.)
"When he was sixteen, after a long consultation with the cardiologist, we declined a heart operation, having been told that he had possibly only a fifty per cent chance of survival. Life has had many ups and downs over the years, and I cannot pretend that things have always been easy. He is still ill at times, he is blue and gets breathless and tired, but he seems to enjoy life to the full. We celebrated his twenty-first birthday with a big party and disco for family and friends, and a year later he was best man at his brother's wedding, and looked extremely smart in his grey tail suit and waistcoat."