Unfortunate that you lost your dad at a young age. How does your doctor concluded that your heart is growing? was it on x-ray? was it a cardiac ultrasound
See, most probably your father had a dilated cardiomyopthy. the cause for which cold
not be known. it may run in families but you must get an ECHO to be sure of that. it has so many treatment options now. so don't get depressed. first ensure that you have some disease and then seek its treatment if it is there. feel free to discuss further.