[Twenty years of epidemiology of acute coronary syndromes in Italy: how cardiovascular epidemiology can guide secondary prevention strategies].

Over the last 20 years the epidemiology of acute coronary syndromes (ACS) has significantly changed, affecting both the acute and post-acute phases. In particular, although the progressive reduction in in-hospital mortality, the trend in post-hospital mortality was found to be stable or increasing. This trend was at least in part attributed to the improved short-term prognosis due to coronary interventions in the acute phase, which ultimately have increased the population of survivors at high risk of relapse. Thus, while hospital management of ACS has shown great progress in terms of diagnostic and therapeutic efficacy, post-hospital care has not had a parallel development. This is certainly partly attributable to the inadequacy of post-discharge cardiologic facilities, so far not planned according to the level of risk of individual patients. Hence, it is crucial that patients at high risk of relapse are identified and initiated into more intensive secondary prevention strategies. On the basis of epidemiological data, the cornerstones of post-ACS prognostic stratification are represented on the one hand by the identification of heart failure (HF) at index hospitalization, on the other hand by the assessment of residual ischemic risk. In patients presenting with HF at index hospitalization, the fatal rehospitalization rate increases by 0.90% per year from 2001 to 2011, with a mortality between discharge and the first year which in 2011 was equal to 10%. The risk of fatal readmission at 1 year is therefore strongly conditioned by the presence of HF which, together with age, is the major predictor of new events. The effect of high residual ischemic risk on subsequent mortality shows increasing trend up to the second year of follow-up, moderately increasing over the years until reaching a plateau around the fifth year. These observations confirm the need for long-term secondary prevention programs and implementation of a continuous surveillance in selected patients.