'A twist in the heart' - Echocardiographic diagnosis of criss-cross heart.

Criss-cross heart is an extremely rare congenital anomaly seen in less than 0.1% of all congenital heart diseases. We present a case of criss-cross heart in a 13-year-old boy. Suspicion of criss-cross heart occurred when all the four chambers of the heart could not be profiled in a single four-chamber view and a vertical septum was noticed in parasternal short-axis view. In this patient there was a ventricular septal defect along with this anomaly. Criss-cross heart usually presents with atrioventricular concordance and ventriculoarterial discordance. This case is unique and rare with atrioventricular and ventriculoarterial concordance. <Learning objective: Suspicion of criss-cross heart is made when it is not possible to visualize all the four cardiac chambers in the apical four-chamber view. Crossing of inlets is seen when posterior to anterior sweep is made by probe. Criss-cross heart throws light onto the concept of situs concordance and alignment. There is no exact mechanism described for this condition. One of the proposed mechanisms by Anderson et al. is the concept of post-septational rotational abnormality which suggests further rotation of heart post looping to decide the position of the apex.>.