Welcome to HealthcareMagic forum.
Cardiac activity usually starts by 5-6 weeks of pregnancy
. This activity is picked up much earlier / easily by transvaginal ultrasound
. And rarely this activity may occur at a later date.
It would be early to predict the prognosis of the condition now. I would suggest to repeat the scan a week or two later. Absence of cardiac activity in the future scans would mean an ominous sign.
Hope this answers your query.