Patients with an LVEF percentage between 40 and 50% and with specific forms of cardiomyopathy, such as those due to genetic mutations (e.g., Lamin A/C, filamin-C, and phospholamban), arrhythmogenic LV CMP, or hypertrophic CMP, may require ICD therapy. The gene discussed is FLNC; the disease is cardiomyopathy.