Radiation chemotherapy induced heart problem

20 years ago had chemotherapy (doxirubicin) mediastinal radiation.I have symptoms of excersize intolerance, diziness, cough, abdominal bloating. My ekg showed new LBBB. Echo says. Interventricular septum is dyskinetic and LVEF mildly depressed chamber size and lv thickness normal. No valve stenosis. Moderate mitral and mild tricuspid regurgitation
LV [d]. 48
LV [s] 34
E.F. 50 %
Cardiologist said this is no big deal. Yes exact words. Im not feeling this sounds right. Mostly because im not feeling well Ive had a chronic cough for 4 months.

[CCF HeartMD6]

Having previous exposure to cardiac-toxic medications as well as mediastinal radiation can put you at risk for developing heart problems much later in life.  Unfortunately, it is impossible to make an accurate diagnosis over the internet.  The results of your echocardiogram is incomplete -- but would suggest at least that your LV function is normal and the dimensions of your LV cavity are within normal limits. However, there are other measurements that are done that can provide useful information.  As far as your symptoms are concerned, it is again difficult to say exactly what is going on as the differential diagnosis is extremely wide, and includes issues with the heart, lungs, and GI system. If you are having signs/symptoms of heart failure (weight gain, lower extremity edema), you should re-consult your cardiologist (or a second opinion) where a complete history and physical examination can take place.  

[gingertazz]

Sorry I didnt  define my question. Is this a serious condition? Should i have furrther test or treatment