Criss-cross heart is a rare congenital cardiac anomaly characterized by crossing of the inflow streams of the two ventricles, due to an apparent twisting of the heart about its long axis and when the axes of the openings of the atrioventricular (AV) valves
CASE REPORTS Case 1At 19 weeks' gestation after spontaneous conception, a Caucasian woman, gravida 4 para 2, was referred because of abnormal four-chamber and great artery views. Fetal echocardiography showed normal situs and heart position. The atrioventricular (AV) connection was double-inlet right ventricle (DIRV) with a right-sided rudimentary left ventricle (LV). There were two separate AV valves. However, the right valve opened obliquely into a left-sided morphological right ventricle (RV). The left AV valve straddled the interventricular septum, leading to flow crossing from the left-sided atrium to a rightsided rudimentary LV although it opened mainly into the left-sided ventricle (Figure 1). The ventriculoarterial (VA) connection was double-outlet RV (DORV) with two good size arteries, with a left-sided anterior aorta. Systemic and pulmonary veins drained into the appropriate atria.The parents were informed of the need for univentricular repair and opted for termination of pregnancy. Postmortem examination confirmed the ultrasound findings: the right AV valve opened to the left-sided ventricle and approximately 40% of the left valve drained to the right-sided ventricle (Figure 2), producing a criss-cross effect when the two AV valves were seen together.
Case 2A Mediterranean woman, gravida 2 para 0, was referred at 20 weeks' gestation with abnormal views of the fetal heart. She had taken ovulation drugs (clomiphene) prior to conception and chorionic villus sampling was performed at 11 weeks' gestation because of increased nuchal translucency (5.9 mm). Karyotype was normal. Fetal echocardiography showed normal situs and cardiac position. The AV connection was DIRV with two AV valves. The right-sided valve overrode the ventricular septum, and opened towards a large and dominant morphological RV situated on the left. The left-sided valve opened mainly into this ventricle, but it also opened into a smaller right-sided LV. This resembled a criss-cross relationship of blood flow at the AV level (Figure 3). The VA connection was DORV with a left-sided, anterior aorta. There was significant pulmonary stenosis, with increased velocity across the pulmonary outflow tract and reversal of flow in the arterial duct. Systemic and pulmonary venous return was normal.A male infant was delivered at term and prostaglandin E was commenced. Neonatal echocardiography confirmed the sequential segmental analysis with a superoinferior position of the ventricles. A modified Blalock-Taussig