Steroids really are not going to help you loose weight. You could run a low dose of Anavar (5mg a day) while on a significant calorie deficient diet to help maintain existing muscle mass. But the diet is what is going to help you loose the weight. I would also quit the cardio and work on lifting the weights and pushing hard while doing it.
Your heart is already too taxed due to your weight to try Clenbuterol or T3.