Hypertrophic cardiomyopathy (HCM) may remain clinically silent and undiagnosed until patients reach advanced age. We describe 2 older patients with previously undetected and probable late-onset HCM whose preoperative cardiac examination revealed only the presence of a systolic murmur. Both patients were diagnosed with HCM by perioperative echocardiography. We provide an algorithm for the evaluation of murmurs detected during the preoperative anesthesia evaluation, with emphasis on the clinical characteristics of HCM, and we discuss the perioperative management of these patients. In addition, recent findings concerning the natural progression of HCM are discussed, revealing differences between HCM in younger patient populations and that in older patient populations and its implications for anesthetic management.