Background: National registries are advocated as instrumental to the solution of rarity-related problems for patients with hypertrophic cardiomyopathy(HCM), including limited access to advanced treatment options. Thus, an Italian Registry for HCM was created to assess the clinical profile and the level of care nationwide of patients with HCM. Methods: Cardiology centers over the national territory were recruited to provide clinical data of all patients with HCM ever seen at each institution. The enrollment period was from May 2000 to May 2002. Results: The registry enrolled 1677 patients from 40 institutions. Most(69% )were followed at referral centers, whereas 31% were from community centers with intermediate-low patient flow. Patients diagnosed after routine medical examinations or familial screenings were 39% . Most patients were male(62% ), in their fourth to sixth decade of life, and in New York Heart Association class I to II(89% ); 24% had resting left ventricular obstruction and 18% had atrial fibrillation. During a 9.7-year average follow-up, cardiovascular mortality was 1% /y, mostly because of heart failure, with no significant change over the last 3 decades; sudden death was less common(0.4% /y). Only 4% of patients received a defibrillator; 14% of the 401 patients with LV outflow obstruction underwent invasive relief of obstruction; and< 1% were offered genetic analyses or counseling. Conclusions: The Italian Registry represents the first comprehensive attempt to evaluate the clinical impact and management of HCM at a national level. Findings underscore the role of screening strategies for an early diagnosis and suggest limited use of the advanced therapeutic options for HCM. Background: National registries are advocated as instrumental to the solution of rarity-related problems for patients with hypertrophic cardiomyopathy (HCM), including limited access to advanced treatment options. Thus, an Italian Registry for HCM was created to assess the clinical profile and the level of care nationwide of patients with HCM. Methods: Cardiology centers over the national territory were recruited to provide clinical data of all patients with HCM ever seen at each institution. The enrollment period was from May 2000 to May 2002. Results: The registry enrolled 1677 Patients diagnosed after routine medical examinations or familial screenings were 39%. Most patients were male (62%) were hospitalized at referral centers, while 31% were from community centers with intermediate-low patient flow. ), in their fourth to sixth decade of life, and in New York Heart Association class I to II (89%); 24% had resting left ventricular obstruction an During a 9.7-year average follow-up, cardiovascular mortality was 1% / y, mostly because of heart failure, with no significant change over the last 3 decades; sudden death was less common (0.4% / Only 4% of the 401 received with defibrillator; 14% of the 401 patients with LV outflow obstruction underwent invasive relief of obstruction; and <1% were offered genetic analyzes or counseling. Conclusions: The Italian Registry represents the first comprehensive attempt to evaluate the clinical impact and management of HCM at a national level. Findings underscore the role of screening strategies for an early diagnosis and suggest limited use of the advanced therapeutic options for HCM.