Hi it all depends on how is his clinical scenario. In ac joint dislocation there are grade 3 a and grade 3b. Grade 3a can be treated without surgery and grade 3 b can also be treated without surgery if the activity level is not demanding and age is high. In athletes and young grade 3 b requires surgery. I can share you pics of my operated cases and help you treat your Relative.

Mini open A’scopic assisted AC joint reconstruction with Semi T and dog bone. Depends on clinical examination and images

Considering his age and heart status, I would suggest non-operative.. Grade 3 AC joint dislocation is a grey zone which can be managed operative or non-operatively. Please share Xray n problems that your father is encountering.

Grade 3 AC dislocations in a cardiac patient should be treated without operation. In three months time, he will be back to his normal life

Arthroscopy

In the first instance need to know his main complaints . Not all patients with Type 3 AC joint injury need surgery . If survey is planned would recommend arthroscopic AC joint reconstruction

Grade 3 AC joint dislocation should be managed without operation . He would not have any problems.

Both are good methods Depends upon expertise of doctor rather than technique Otherwise arthroscopic is always better if done by expert