P2315The Portuguese registry of hypertrophic cardiomyopathy (PRO-HCM): global results

Abstract

Aim: Most national registries on hypertrophic cardiomyopathy (HCM) were published before recent diagnostic and therapeutic advances and largely originate from major tertiary referral centers. We report the results of the Portuguese Registry of Hypertrophic Cardiomyopathy (PRo-HCM), a contemporary effort representing the entire spectrum of cardiology centers over the national territory. Methods: A direct invitation to participate was sent to central and regional, public and private, academic and non-academic cardiology departments. Baseline and outcome data were collected and assessed. Results: 29 centers participated; the total number of patients recruited was 1042; four centers recruited 49% of the patients; 59% were male and mean age at diagnosis was 53±16 years. HCM was identified as familial in 33%. The major reason for diagnosis was symptoms (53%). HCM was obstructive in 35% (labile in 11.5%, resting 88.5%); 11% had atrial fibrillation. Genetic testing was performed in 51%. Invasive septal reduction therapy was offered to 8% of the whole cohort (surgery 6%, alcohol septal ablation 2%), but to 23% of obstructive patients. Most patients (83.5%) had an estimated 5-year risk of sudden death <6%. 13% received an implantable cardioverter defibrillator, largely (88%) for primary prevention. After a mean follow-up of 5.3±6.1 years, median 3.3 years, interquartile range (P25-P75) 1.3 - 6.5 years, only 31% of patients were asymptomatic. All-cause mortality was 0.93%/year and CV mortality 0.48%/year. The incidence of HF-death was 0.26%/year, of SCD 0.13%/year and of stroke-related death 0.04%/year. HF-death plus heart transplant occurred 0.27%/year and SCD plus equivalents (succcessful cardio-pulmonar ressuscitation or appropriate ICD shocks in the setting of primary prevention) occurred with an incidence of 0.35%/year. Conclusions: According to data from a large number of patients, contemporary HCM in Portugal is characterized by relatively advanced age at diagnosis and an important number of obstructive forms with invasive treatment. Long-term mortality is low, HF is the most common cause of death while SCD is uncommon. However, the burden of morbidity remains considerable, emphasizing the need for disease-specific treatments impacting the natural history of the disease.