Ivemark Syndrome

Polymalformative syndrome associating complex cardiac anomalies, situs inversus, absent spleen, abnormal inclusions in red blood cells, and immunocompromised state.

Asplenia Syndrome; Polhemus-Schafer-Ivemark Syndrome; Splenic Agenesis Syndrome.

Autosomal recessive; a few cases transmitted as an autosomal dominant trait, but most cases are sporadic. X-linked inheritance of heterotaxy syndromes is known.

Unknown. Disorder of the laterality (i.e., heterotaxy anomaly). Trisomy 9 associated in one case. Chromosomal anomalies, intrauterine infection, and environmental/toxic factors have been suggested as etiologic factors.

Asplenia (or splenic hypoplasia) associated with congenital heart disease, renal dysplasia, hepatic dysplasia, pancreatic dysplasia, and abnormal lobar development of the lungs. Could be evocated before birth by ultrasonographic examination showing asplenia and lateralization anomalies.

Asplenia is combined with bilateral right-sided organs. There are two right lungs, two right lobes of the liver, two right atria, and bilateral superior vena cava. Various abnormal localizations of single organs are observed. This syndrome cannot be qualified as situs inversus. Clinical manifestations include sensibility to infection with encapsulated germs and presence of Heinz and Howell-Jolly bodies in the blood because of asplenia. Cardiac malformations (single ventricle, transposition of great vessels, truncus arteriosus, atrioventricular defect) are frequent with their own signs; arrhythmia as a result of the presence of two sinoatrial nodes is specific. Neurologic signs could be observed in relation with anophthalmia, holoprosencephaly, hydrocephalus, or meningocele. Hepatogastrointestinal structures can be abnormal and complicate evolution of the syndrome: biliary atresia or stenosis, hiatus hernia, megaesophagus or brachyesophagus, volvulus as a result of malrotation of the gut, and malformation of the pancreas. Up to 70% of patients die within the first year of life.

History and examination define the associated anomalies. Cardiac assessment. Inquire about a history of cyanosis or systemic-to-pulmonary shunt formation. Electrocardiography (ECG) and echocardiography are mandatory. Angiography and cardiac catheterization as indicated clinically. Pulmonary assessment. Chest radiography to exclude infection and pulmonary edema. Preoperative blood gases in presence of cyanosis. Laboratory tests: check electrolyte levels and renal function, liver function, coagulation status, and full blood count.

Cardiac and pulmonary function are the main considerations. In the presence of systemic-to-pulmonary shunts, blood pressure may vary in different limbs. Aim to maintain ratio of pulmonary flow to systemic flow and prevent large decreases in pulmonary vascular resistance or systemic vascular resistance (balanced anesthesia, minimum fraction of inspired oxygen [FiO2], prevent hyperventilation). Maintain preoperative arterial oxyhemoglobin saturation (SpO2). In the presence of right-to-left shunting, maneuvers to decrease pulmonary vascular resistance (hyperventilation, increased FiO2, positive end-expiratory pressure) may be beneficial. Potential need for postoperative ventilation.

Caution with high-dose volatile agents, myocardial depression, and decreased systemic vascular resistance. Inotropic support may be necessary. Antibiotic prophylaxis for cardiopathy as indicated.

Heterotaxy Syndromes (Defects of Laterality): X-linked syndromes with laterality defects varying from situs inversus that is the complete reversal of the normal anatomical distribution of viscera to various degrees of situs ambigus (randomization of the normal organ position) that may manifest as asplenia or polysplenia syndrome.

Kartagener Syndrome: Autosomal recessive polymalformative syndrome characterized by bronchiectasis, situs inversus, and chronic sinusitis. Caused by mutations in the gene encoding axonemal dynein intermediate chain (DNAI1), which maps to 9p21-p13. Can be caused by a mutation in the DNAH5 gene (5p15-p14).

Polysplenia: Some authors consider polysplenia to be a related syndrome, whereas other authors think it is the same entity. Patients with this syndrome are bilaterally left sided.

Asplenia with Cystic Liver, Kidney, and Pancreas: Autosomal recessive. Also described by Ivemark and characterized by polycystic lesions of liver, kidney, and pancreas.