Been diagnosed with an ef of 50%. 51 yo male, clear cath, no heart attack. right side of heart normal, left mild dysfunction. how serious is this?

Not too: That ef is at the lower end of normal; however if you have high blood pressure lowering it might improve your heart function and your ef. There are specific blood pressure medicines your doctor can prescribe if you have "diastolic dysfunction" and if you are other wise healthy and can exercise that will improve your heart function as well.

At this moment: Your ejection fraction is mildly low. Normal more than 55%. Normal coronary arteries a diagnosis of non-ischemic cardiomiopathy is possible. 2d echocardiogram necessary to classify in 4 types: dilated, hypertrophic, restrictive or arrhythmogenic right ventricular dysplasia. Dilated the most common, cause by unknown etiology, alcohol, virus, drugs, thyroid disease. Close follow up with cardiology.