<unk>  or Eisenmenger's reaction is defined as the process in which a left-to-right shunt in the heart causes increased flow through the pulmonary vasculature, which leads to pulmonary hypertension, which finally causes increased pressures in the right side of the heart and reversal of the shunt into a right-to-left shunt. This right to left shunt causes the patient to become cyanotic. Thus,<unk>  is said to develop when there is a pulmonary artery disease, right-to-left heart shunting and cyanosis. Victor Eisenmenger first described the syndrome in 1897 in a patient who presented with dyspnea and cyanosis since infancy. Since then, advances in the medical treatment of pulmonary hypertension improved the survival of<unk> .<unk>  can be classified according to the underlying congenital heart disease into simple and complex. Histologically, six stages were identified by Heath and Edwards, ranging from reversible to irreversible and terminal. The progression of a heart defect to<unk>  depends on the size of left to right shunt, severity of pulmonary vascular disease, and type of defect. The left-to-right shunt at the start increases the pulmonary vascular flow and leads to pulmonary artery hypertension. This causes damage to the delicate pulmonary capillaries, creating scars and fibrous tissue. This leads to hypoxemia, which is compensated by increased RBCs production, leading to polycythemia and hyperviscosity syndrome. Eventually, the building pressure in the pulmonary circulation will cause shunt reversal and development of<unk> .<unk>  is causes by cardiac defects that shunt blood heading to the systemic circulation back into the pulmonary circulation. These defects include ventricular septal defect, atrial septal defect, atrioventricular canal defect, patent ductus arteriosus, and truncus arteriosus.<unk>  should be differentiated from idiopathic pulmonary hypertension, pulmonary infarction, respiratory failure, tricuspid atresia, persistent truncus arteriosus, and other congenital heart diseases. The incidence and prevalence of<unk>  has been decreasing gradually over the years. In the general population, the prevalence decreased from 24.6 to 11.9/million inhabitants in 2012. About 8% of patents with congenital heart diseases develop<unk> . The mortality rate of<unk>  is about 27%. The risk of<unk>  increases in patients with large cardiac defects or who live in developing countries due to poor healthcare access. The common risk factors for<unk>  include genetic mutations, exposure to rubella virus, and drug and alcohol abuse during pregnancy. Less common risk factors include poor healthcare access and patients in developing countries. There are currently no guidelines on using echocardiography to screen patients with CHD for the presence of pulmonary arterial hypertension. However, some parameters are recommended as pedictive for the development of pulmonary arterial hypertension, including peak tricuspid regurgitation velocity, ventricular basal diameter ratio, systolic and/or diastolic ventricular eccentricity index, RV outflow Doppler acceleration time, pulmonary artery diameter, and inferior vena cava inspiratory collapse.<unk>  passes through different stages, including the causative  left-to-right shunt, development of pulmonary hypertension, polycythemia, and shunt reversal. The complications of<unk>  include intracranial hemorrhage, stroke, congestive heart failure, angina pectoris, hyperviscosity syndrome, infection (cerebral abscess), renal failure, and sudden death. How well the infant or child does depends onwhether another medical condition is present and the age at which high blood pressure develops in the lungs. Patients with<unk>  can live 20 to 50 years. Echocardiography is the first line diagnostic modality of<unk> . Findings on an echocardiography suggestive of<unk>  include underlying cardiac lesion responsible for the shunt, direct of the shunt, and elevated right ventricular systolic and pulmonary artery diastolic pressures. Patients with<unk>  pass through the following stages: An underlying heart defect that initially allows a left-to-right shunt between the left and right sides of the heart, then the development of pulmonary hypertension, then polycythemia, an increase in the number of red blood cells, and finally, a reversal of the left-to-right shunt so that there is a right-to-left shunt. The common symptoms of<unk>  include dyspnea, syncope, hemoptysis, chest pain, dizziness, fatigue, and dyspnea. The general examination of patients with<unk>  may show cyanosis, dermal changes, clubbing, peripheral edema, and abdominal swelling. Cardiac examination may show A wave dominant jugular venous pulse, right ventricular heave, high-pitched early diastolic murmur of pulmonary insufficiency, right-sided S4, pulmonary ejection click, single palpable S2, and loud P2. The laboratory findings of patients with<unk>  include erythrocytosis, iron deficiency, increased bleeding time, increased blood uric acid and conjugated bilirubin concentrations, as well as mixed respiratory and metabolic acidosis. Eisenmenger's patients may show some ECG findings, including right axis deviation (ventricular hypertrophy), ST changes (Right ventricular or biventricular hypertrophy), P Pulmonale (Right atrial hypertrophy), tall R wave in V1 and deep S wave in V6, and microvolt T-wave alternans. Chest X-ray of patients with<unk>  may show cardiomegaly, right ventricular or biventricular enlargement, right atrial or biatrial enlargement, and pulmonary vascular plethora. Echocardiography is the first line diagnostic modality of<unk> . Findings on an echocardiography suggestive of<unk>  include underlying cardiac lesion responsible for the shunt, direct of the shunt, and elevated right ventricular systolic and pulmonary artery diastolic pressures. Computed tomography can be helpful as a diagnostic tool in conditions where the echocardiographic findings are inconclusive. The findings on CT scan may include large main pulmonary artery, ventricular septal defect, and right ventricular hypertrophy. Magnetic resonance imaging can be helpful as a diagnostic tool in conditions where the echocardiographic findings are inconclusive. The following can be observed on MRI examination of<unk>  patients: Magnitude and direction of the cardiac shunt, reduced systolic function of the cardiac ventricles, and brain diffusion changes on brain MRI. Cardiac catheterization is useful in patients with<unk>  in terms of assessing the severity of pulmonary hypertension, coexisting congenital anomalies, degree and direction of shunting, ventricular function, pulmonary artery pressure and flow, and calculation of pulmonary vascular resistance. There are no other diagnostic studies associated with<unk> . If surgical intervention is not available, treatment is mostly palliative. It includes anticoagulants, pulmonary vasodilators such as bosentan, PGE 5 inhibitor, prostacyclin, antibiotic prophylaxis to prevent endocarditis, phlebotomy to treat polycythemia, and maintaining proper fluid balance. Congenital heart defects should undergo surgical repair before progression to<unk> . Once the condition develops into<unk> , no surgical cure is available except for heart and lung transplantation. However, palliative interventions (as creation of an artificial ASD) may prolong the lifespan and improve the quality of life. Surgery as early as possible to correct the heart defect can prevent<unk> . Due to the irreversible nature of<unk> , there are no established measures for the secondary prevention.
Eisenmenger’s syndrome
Eisenmenger's syndrome
Boerhaave syndrome
Bland-White-Garland syndrome
Meigs syndrome
Lown-Ganong-Levine syndrome
Avasthey syndrome
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