The answer to this question depends on a variety of factors, including the overall health of the individual, age, lifestyle, and other medical conditions. Generally speaking, however, it is possible to live with 20 percent heart function for an extended period of time.
In some cases, individuals with 20 percent heart function can have a normal life expectancy. This is possible because the heart is capable of compensating for some of the reduced function. For example, individuals may develop an increased heart rate, which can help to maintain adequate blood flow. It is also possible for the heart to develop thicker walls, which can help to increase its overall strength and efficiency. In addition, medications and lifestyle changes may be able to reduce the workload on the heart and slow down the rate of deterioration.
However, the outlook for individuals with 20 percent heart function is not always positive. If the individual has other medical conditions or a poor lifestyle, then the outlook may not be so optimistic. Additionally, if the heart's function continues to deteriorate, then the individual may eventually need a heart transplant or other forms of life-saving medical intervention.
Overall, it is possible to live with 20 percent heart function for an extended period of time. However, the outlook can vary greatly depending on a variety of factors, including the individual's overall health, age, lifestyle, and other medical conditions.