Hi, welcome and thanks for writing in
Alelectsais is a condition where the alveoli are deflated, as distinct from pulmonary consolidation. It is a very common finding in chest x-rays and other radiological studies. It may be caused by normal exhalation or by several medical conditions. It may also seen due to old infections. Infiltration or congestion are changes of pneumonia. It is absent in your Xray. So atelectasis is most likely related to old infections.
Cardiomegaly means increase in the size of the heart. It may be age related or pathological. Considering your age it is a normal finding on chest xrays.

If you don't have symptoms like cough, breathlessness or fever then your chest xray is not showing any major illness. So no need to worry about that.

Hope I have answered your query. If you have further concern, please let me know.

Regards.

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