1 yr old breathes fast (45bpm). took her to dr, who did chest xray. showed prominent perhiliar markings. is this a sign of heart issues? she has been breathing fast for over 1 month had a cold 3 week ago, with 104 fever that became ear infection too?

She may have had a chest infection last month and this could result in bronchospasm. Was there a COVID screening test performed last month? If she had COVID, the symptoms may take some time to resolve. Cardiac conditions should be considered even without the presence of a murmur. The chest x ray report will also comment on the shape and size of the heart. Watch for worsening with exercise, wheeze.

Prominent perihilar markings is a common description applied to a kids' chest x-ray when they didn't take a deep enough breath before the tech took the film, or in the weeks after a simple respiratory infection. It does not suggest a heart condition. The doc who ordered the film can decide whether this is worth mentioning.