Cardiovascular diseases are one of the leading causes of death in the County of San Bernardino, California. There are various efforts that have been put in place to manage the prevalence of the complications including the incorporation of borrowed theories and mid-range theories. This study used case study based qualitative research design approach to evaluate the impact of borrowed theories and mid-range theories on the prevalence of cardiovascular disease in San Bernardino County. The findings of the study indicated that the adoption of the aspects of borrowed theories such as positive attitudes towards prevention of cardiovascular diseases, positive subjective norms such as keeping blood pressure within normal range and positive perceived behavioral control features leads to the reduced disease prevalence. The study also indicated that lower prevalence of cardiovascular diseases is associated with adoption of various aspects of mid-range theories such as self-efficacy, adherence to preventive screening and disease awareness.