FTS High NT 5.5

Anyone had experience with very high NT score? I am currently at 13 weeks and my FTS at KKH flagged out that my baby has an abnormally high NT at 5.5. NIPT listed us as Lowrisk for DS but we were still thrown many scary statistics and possibilities for other abnormalities. Currently scheduled for amniocentesis at 16 was and detailed cardiac scan. May I know if anyone had experience with such high NT before?