Robert Freitas had a very interesting essay a few years back called "Death is an Outrage", which discusses how long life spans could be extended if our bodies could be rejuvenated and maintained without aging as a factor.
If we cure diseases but do not have effective rejuvenation then we get less overall life extension because more age related diseases and degeneration continue to cause more deaths as we age. The problem of "if one thing does not kill you then something else will".
There was an analysis that if cardiovascular disease (all major forms of heart and blood vessel disease were eliminated), U.S. life expectancy would rise by almost seven years and the nation would be more than $300 billion richer.
However, if we cured cardiovascular disease and had powerful rejuvenation therapies then the overall benefit of curing the disease would be an extension of life expectancy by closer to 20 years.
Curing heart disease and cancers would provide a combined elimination of about 50% of medically preventable disease. Combined with effective rejuvenation techniques would provide a 151 year life expectancy. Eliminating 90% of disease deaths along with effective rejuvenation would provide lifespans of 512 years.
Curing Heart disease strategy :
early detection of the soft blisters that burst which then lead to plaque formation (pre-blockage detection) and then treatment.
More aggressive monitoring of risks and indicators (getting on top of higher cholesterol and other problems before it results in heart and arterial diseases / failures)
Stem cell treatments
Effective Lifestyle mitigation therapies
Curing Cancer strategy
Effective early detection
Understanding the processes in molecular detail and the pathways
Developing interventions against it at key stages
Effective tumor treatments
Some cancers that are not cured could become manageable conditions like aids or diabetes now.
Progress is being made with stem cells, organ and tissue regeneration and replacement. These things have the potential to provide a powerful rejuvenation capability.
Strategies for Engineered Negligible Senescence also continues to get more funding and is making some progress. It has its own scientific projects funded and is influencing more researchers to work towards the goals that they have defined, which is life extension escape velocity.