1). The type of x-ray performed with regard to position, if it's an AP view (anterior/posterior) then the heart shadow is almost always enlarged
VS. PA view.
2). Your medical history : high blood pressure (hypertension /htn), alcohol use, obesity, etc.
3). An ekg & echocardiogram (heart ultrasound) is needed to determine the size of the chambers, overall heart function & any parts of the heart walls that may not be moving well, etc.
This will give many clues to a possible diagnosis if your heart is truly enlarged.
4). If the echo is abnormal then more testing is needed : a stress test & depending on the outcome of that then a cardiac cath most likely will be needed to rule out some other causes.
So surgery is not the first option & it truly depends on the underlying cause.
Have your doctor refer you to a local cardiologist for further examination & treatment options asap.
I hope that helps you.
As for surgery being unavoidable,that would depend on multiple factors: severity of symptoms, response to medical therapy, etc.
First, let me be clear, an xray is not a very reliable method for imaging the heart. It would require additional evaluation by ECHOCARDIOGRAPHY which is very easy to do and very diagnostic. If your heart is truly enlarged there may be other treatments required. But it must be established that your heart IS enlarged by a better modality.
But it all depends on your heart and the details.
Best to have a thorough examination with a cardiologist to make a diagnosis and discuss all available options.