If i changed my exercise regime, would i be able to avoid heart failure?

No: Heart failure happens because the muscle of the heart is too weak because it has a disease that affects the muscles, had heart attacks in the past, has some infiltration into the heart muscle or has been enlarging because hypertension or a virus, or valvular disease caused by streptococcus ( rheumatic fever) or damage to the valves from endocarditis or lupus etc. ( cardiomyopathy).

Good idea: There are never guarantees but a good exercise routine that includes cardio is always a good idea.