A small subset of patients with an LVEF <50% (end-stage disease) or an LV aneurysm warrant consideration for ICD implantation.S7.4-52 HCM indicates hypertrophic cardiomyopathy; ICD, implantable cardioverter- defibrillator; LV, left ventricular; LVEF, left ventricular ejection fraction; LVOT, left ventricular outflow tract; NSVT, nonsustained ventricular tachycardia; SCD, sudden cardiac death; VT, ventricular tachycardia; and VF, ventricular fibrillation. CLINICAL STATEMENTS AND GUIDELINES associated with a risk of sustained monomorphic Age is also an important consideration, as sudden death risk is greater in those <30 years of age, and low in patients whose initial presenta- tion is after the age of 60 years,S7.4-5,S7.4-26 2. HCM is the most common cause of SCD in individuals <40 years of age.S7.4-26 Individuals who have survived an episode of SCD, VF, or sustained VT resulting in syncope or hemodynamic compromise warrant ICD Although there are no RCTs assessing the use of the ICD in patients with HCM who have survived SCD, 1 study reported that 54% of patients with an ICD placed for secondary prevention received appro- priate ICD therapy during an average follow-up of Select patients with HCM may be candidates for implantation of the subcutaneous ; how- ever, more data on this group are needed especially given their higher risk of T wave oversensing that may increase the risk of inappropriate ICD shocks. 3. Clinical and/or genetic screening of first- and second-degree family members of patients with HCM is important to identify those with unrec- ognized disease. 