Thanks for your query.
Foetal heart can be best studied on ultrasound
between 22-24 weeks of pregnancy
,Fetal cardiac abnormality is quite common these days . Pouch in the left ventricle of fetal heart suggest some cardiac problem . So fetal heart echo at 24 weeks from some very good ultrasonologist trained in fetal echo is must to know the exact diagnosis .Without complete diagnosis it is impossible to say whether it is life threatening or not.
‘Hope I have answered your query, I will be available to answer your follow up queries, “Wish you Good Health and trouble free speedy recovery”