Describe PS With Atrial Right To Left shunt in details?

This group of patients has cyanosis due to light to left shunt at atrial level. The diminution in PA pressure and PBF may or may not be due to PS 'per se. There is triad of cyanosis, cardiomegaly, and ischemic lung fields in chest X-ray. There are only two conditions:
1) Several critical pure Pulmonary stenosis with failing heart.
2) Ebstein's anomaly of Tricuspid valve with PS.

Clinical Features: Cardiomegaly, Parasternal impulse, Single audible S2; P2 late and soft, S3, S4 present, Pulmonary ESM present. The duration of ESM is directly proportional to severity of PS. Ejection click may be audible. Tricuspid regurgitation murmur present. Post-stenotic dilation of PA on Chest X-ray.

Figure : Ps with aterial RT lo Left septum