The ICD/pacer and bypass surgery (for the blocked arteries) are completely different procedures.
The damage from the MI probably did enough damage that his heart is experiencing dangerous rhythms. The ICD/pacer is needed in case he needs a shock for the rhythm issues.
The bypass surgery is completely different.
are you saying they have now decided against the bypass and instead are now just doing the ICD/pacer? That's a question best posed to his doctor.
I don't understand your question, but:
1) I believe bypass surgery (to replace blocked arteries) is not considered "open heart surgery".
2) I believe a defibrillator and pacemaker do not require open heart surgery.
Why do you want open heart surgery?