I am not to sure what you are asking.
I believe you are asking if the igf will enlarge your heart, however you running 40 mcg/ed for 28 days, there really is nothing you should be worried about. Im not to sure what your goals are either. Are you looking for localized growth or just to keep your gains in pct?
If you are looking for localized growth i would suggest pinning bilaterally into the muscle worked that day IMMEDIATLY after your last set ( and i mean within 2-5 mins). However if you are looking for a steady increase in protein synthesis over the course of the day ( which would have a much greater systemic effect, if you were worried about the cardiac hypertrophy) Then i would suggest trying it the Lake way 2x a day, maybe tossing in some MGF if your wallet will afford it but, this isnt necessary.
Also you may just want to try out 20mcg / day at first. I have seen numerous people get great results with these low doses which are still MUCH more than your body produces daily. Either way good luck bro and there are many logs in this forum about different dosing methods so check em out.