TweetWhen I do hiit I aim to keep my heart rate at 85% minimum and max it out sometimes for the VO2 max effect. Part of HIIT that makes it so good is getting that heart rate up in the 150s+. If you cannot get your BPM over 117 it would be hard to do proper HIIT. Maybe a less intense version where you do not push as hard?
For your health i would stick with making sure the ole ticker is happy and not push it until the doc says otherwise.