A method of treatment or prophylaxis of a disease state or a condition ameliorated or prevented by electromagnetic field application. A person having or susceptible to such disease state or condition is subjected to electromagnetic fields having a frequency between zero and about 200 Hertz. The diseased state or condition may include diseased heart valves, an enlarged heart, circulatory blockage, coronary insufficiencies, and ischemia. The treatment may be administered non-invasively or invasively. An implantable device for invasively administering the treatment may include at least one component emitting electromagnetic fields having a frequency between zero and about 200 Hertz. The component may include at least one inductor.