Brief Answer:
ecg is only a suggestive base line test !

Detailed Answer:
Hi XXXXXXX
Firstly thanks for choosing health care magic for your query!

Have seen your ecg , bifid P wave in lead II can be seen which is suggestive of left atrial enlargement,, however i would like to tell you that ecg is a base line test of cardiology and change in size of left atrium can only be predicted on the basis of ecg .
Ecg is not a diagnostic test for left atrial abnormality ,you should go for a 2d echocardiogram , any abnormality in size and dimesion or motion of any chamber of heart would be reflected in it and a diagnosis can be reached after that on the basis of reports of 2d echo.
As per your question about possible diagnosis,
Obesity and high blood pressure are most common cause of left atrium enlargement , LA enlargement is mostly the result of pressure(hypertension) and/or volume(valve dysfunction) overload. LA enlargement due to pressure overload is usually secondary to increased LA afterload in the presence of mitral stenosis or LV dysfunction.
So it can be secondary to hypertension, mitral stenosis ,mitral regurgitation , left atrial myxoma,Aortic stenosis etc. A 2 d echo will help you to rule out the cause of left atrial abnormality.
Future complication and prognosis depends on the cause of left atrial abnormality , different diseases have different complication and prognosis, 2d echo cardiography report is a must before making any diagnosis.
You have not mentioned whether you are a hypertensive or not , do you have any symptoms ?why was the ecg done ? were you symptomatic having any problem or it was a part of routine check up?

So please provide the answers to the question along with 2 d echo report.

In case you have any other query feel free to ask.
Thanks
Dr Rishu Saxena
Cardiologist XXXXXXX hospital ,new XXXXXXX

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