courtney,

First, congrats on your success at weight loss. That is quite an accomplishment.

If the work-out equipment does not have pulse monitoring, I suggest you get your own system to monitor your heart rate. Then, try working at 80% of you target pulse or even less. Try to find that pulse rate that allows you to exercise without causing symptoms. Then, slowly increase your target heart rate every two weeks or so always staying below your symptoms threshold. This is the basics of the Buffalo Protocol.

Keep in mind that some of the equipment may have a jarring effect that can cause a return of symptoms. Avoid any exercises that cause you to strain such a weights.

With some watchful experimenting, you should be able to find a workup level that does not cause symptoms.

My best to you.