Modified Senning Procedure for Treatment of Transposition of the Great Arteries with Crisscross Heart.

Clinical Data: A nine-month-old female infant diagnosed with transposition of the great arteries with symptoms of heart failure associated with cyanosis and difficulty in gaining weight was referred to our center with late diagnosis (at nine months of age).

Chest Radiography: Cardiomegaly; attenuated peripheral vascular markings.Electrocardiography: Sinus rhythm with biventricular overload and aberrantly conducted supraventricular extra systoles.

Echocardiography: Wide atrial septal defect, ventricular axis torsion with concordant atrioventricular connection and discordant ventriculoarterial connection.

Computed Tomography Angiography: Concordant atrioventricular connection, right ventricle positioned superiorly and left ventricle positioned inferiorly; discordant ventriculoarterial connection with right ventricle connected to the aorta and left ventricle connected to pulmonary artery.

Diagnosis: Crisscross heart is a rare congenital heart defect, accounting for 0.1% of congenital heart diseases. It consists of the 90º rotation of ventricles' axis in relation to their normal position; therefore, ventricles are positioned in the superior-inferior direction rather than anterior-posterior. Most cases have associated cardiac anomalies, and in this case, it is associated with transposition of the great arteries. The complexity and rarity of its occurrence make diagnosis and surgical treatment challenging.

Operation: Modified Senning procedure using the pericardial sac in the construction of a tunnel from pulmonary veins to the right atrium. Cardiopulmonary bypass time of 147 minutes with nine minutes of total circulatory arrest.