The new coronavirus syndrome (COVID-19) is a multi-organ pathological manifestation that, in severe forms, causes greater damage to the respiratory system, especially in the lung district with severe respiratory failure. In many cases, especially in elderly patients with high comorbidity degree, the disease can have a rapid course with a fatal outcome. Specifically, the data relating to the four Italian regions most affected by the effects of the new coronavirus Severe Acute Respiratory Syndrome-CoronaVirus-2 (SARS-CoV-2), namely Lombardia, Veneto, Emilia Romagna and Piemonte, were assessed. In this work, we decided to focus the analysis only on data relating to patients admitted to the intensive care unit and to patients who died in Italy with COVID-19 in the period 24 February-4 May 2020. We used a data set where each point was an expression not of a single day, but of a longer period of time (date-points method). The article clearly identifies the phases in which the epidemic was articulated at national level and in the observed regions. Both the overall national data and the data referring to the most affected regions show an initial exponential mortality trend up to March 21st approximately. From this point the restrictive measures adopted from March 10th shows their effects and the trend first increases only linearly and then finally decreases, also thanks to the implementation of therapeutic strategies aimed at modulating respiratory distress and the clinical condition of thromboembolism, typical of critical patient COVID-19.