Fig. 5: During the third week of development, newly formed mesodermal cells migrate into the area of the germ disk, between the ectoderm and endoderm.
Diagnosis of the complete syndrome requires the five criteria described by Cantrell, but incomplete variant forms exhibiting three or four of the features have been described1. The sternal defect can range from absence of the xiphoid to cleaving, shortening, or absence of the entire sternum. The abdominal defect can range from a wide rectus muscle diastasis to a large omphalocele. The most common intracardiac defects are atrial septal defect, ventricular septal defect, and tetralogy of Fallot6.
The syndrome has been diagnosed prenatally5,7,8, but as the defects range from subtle to severe, the ability to make the ultrasound diagnosis varies. Even at birth, the full extent of the syndrome may not be apparent, as the sternal defect may be minor and therefore without true ectopia cordis. In the case presented, a small open sternal defect was contiguous with the upper portion of the small omphalocele, but the heart and bowel did not protrude through these defects. In the prenatally detected cases which have been reported, ectopia cordis was present.
Differential diagnosis includes isolated ectopia cordis, isolated abdominal wall defect, amniotic band syndrome, and body stalk anomaly. The syndrome should be considered with any diagnosis of omphalocele or ectopia cordis.
In a review of the literature in 1972, Toyama reported a survival rate of 20%. This observation included cases with mild defects and incomplete expressions of the syndrome, and all cases were diagnosed after delivery1. In Ghidini"s 1988 report of 17 prenatally diagnosed cases, 6 patients opted for termination, 4 infants were stillborn, 4 infants died in the first four days after delivery, and the remaining 3 died at one, four, and four months. This gave a survival rate of 0%8. These cases were prenatally diagnosed, so the extent of anomalies could have been more severe than those cases detected at birth. Three of the five patients Cantrell reported in 1958 survived, but none of the five had true ectopia cordis3. Overall the prognosis appears dismal, but may be related to the extent of the ventral wall, sternal, and cardiac defects.
If a diagnosis is made by ultrasound, chromosomal analysis is recommended. Associations with trisomy 18, trisomy 13, and Turner syndrome have been reported4,6. Careful imaging should be performed to rule out associated anomalies. Fetal echocardiography is indicated to evaluate the extent of any intracardiac abnormalities8.
In view of the poor prognosis, termination of pregnancy can be considered if ultrasound diagnosis is made before viability. In patients choosing to continue the pregnancy, there is no data indicating improved or changed outcome with cesarean delivery8.
After delivery, repair of the omphalocele should not be delayed. Repair of the sternal, diaphragmatic, and pericardial defects can be attempted at the same time. Surgical correction is often difficult secondary to hypoplasia of the thoracic cage and inability to enclose the ectopic heart. Some affected infants have respiratory insufficiency secondary to pulmonary hypoplasia. Recognition and treatment of any intracardiac anomaly is important, as congenital heart disease is a source of major morbidity in infants surviving the neonatal period6.
1. Toyama WM: Combined congenital defects of the anterior abdominal wall, sternum, diaphragm, pericardium, and heart: a case report and review of the syndrome. Pediatrics 50:778-792, 1972.
2. Baker ME, Rosenberg ER, Trofatter KF et al: The in utero findings in twin pentalogy of Cantrell. J Ultrasound Med 3:525-527, 1984.
3. Cantrell JR, Haller JA, Ravitch MM: A syndrome of congenital defects involving the abdominal wall, sternum, diaphragm, pericardium, and heart. Surg Gynecol Obstet 107:602-14, 1958.
4. Fox JE, Gloster ES, Mirchandani R: Trisomy 18 with Cantrell Pentalogy in a Stillborn Infant. American Journal of Medical Genetics 31:391-394,1988.
5. Haynor DR, Shuman WP, Brewer DK: Imaging of fetal ectopia cordis: roles of sonography and computed tomography. J Ultrasound Med 3:25-27,1984.
6. Bryke CR, Breg WR: Pentalogy of Cantrell. from Buyse, M.L., Birth Defects Encyclopedia. Blackwell Scientific Publications 1375-76,1990.
7. Abu-Yousef MM, Wray AB, Williamson RA, Bonsib SM: Antenatal Ultrasound Diagnosis for Variant of Pentalogy of Cantrell. J Ultrasound Med 6:535-538, 1987.
8. Ghidini A, Sirtori M, Romero R, Hobbins JC: Prenatal Diagnosis of Pentalogy of Cantrell. J Ultrasound Med 7:567-572,1988.