The ε4 allele of the APOE gene, an allele that is well known for its associations with both cardiovascular disease and Alzheimer’s disease, was associated with both a significantly increased likelihood of DCM development (OR 3.50) [16] and a significantly greater likelihood of failing to gain post-operative improvement (AOR 8.60 no improvement) [54]. The gene discussed is APOE; the disease is early-onset autosomal dominant Alzheimer disease.