Valutazione della funzionalità cardiorespiratoria di soggetti cardiopatici: sviluppo di un test sottomassimale e suo impiego nella valutazione diagnostica e prognostica di 1016 soggetti cardiopatici

The stress tests are widely used in clinical practice to assess the circulatory and respiratory functions of both normal subjects and of subjects with chronic diseases, particularly cardiovascular. The maximum oxygen uptake (VO2max), which is obtained by the use of oxygen during maximal exercise, is widely recognized as the best functional assessment of cardiovascular capacity. During the 3 years of PhD I participated in the development of a sub-test that allows the indirect determination of maximum oxygen consumption. The test developed on 110 heart patients divided arbitrarily and not in Beta Blocked (n = 66) and Beta Blocked (n = 44) tested and running to a maximum cardiopulmonary exercise testing, runs on a treadmill and is the running Km a path of travel at constant speed and sub. The data (average speed and heart rate taken during the test) and the data of the subject under consideration (sex, age, weight, height) are placed into an algorithm: the value that is obtained, predicted VO2max was directly correlated with the VO2 max measured during a VO2max measured between TCP and VO2maxpredetto and not statistically different (P = ns) for both the NBB for the BB. The algorithms have been applied to a set of validation for both the BB and NBB that there were no significant differences between the values of VO2max and VO2maxPRED (P = ns) for the two groups. Finally was made a test of reliability has confirmed the validity of values. The test run performed from 1016 subjects with heart disease related to a cardiac rehabilitation service has been used to study the relationship between functional data, hospitalization and survival of these subjects which show that subjects in the highest quartile have lower risks of hospitalization and death from all causes compared to the other quartiles. The algorithms are highly suggestive and allow for indirect determination of VO2max for heart patients by allowing the clinical assessments of functional capabilities of individuals by reducing the risks of testing limits. We wanted to confirm the prognostic value of the data by checking whether there is a relationship between this and the need for inpatient hospitalization. The subdivision of the study population into quartiles on the basis of VO2maxPRED allowed to document how the group with the highest values of VO2maxPRED have a lower risk of hospitalization for all causes. The same result was confirmed dall'Hazard Ratio, which indicates that membership in the less efficient is a risk factor for hospitalization for any cause. Our results thus confirm that the value of VO2maxPRED from data provided by 1KTWT is a prognostic factor independent predictor of readmission for male subjects included in a cardiac rehabilitation program. Same thing goes for the risk of mortality, belong to groups with VO2maxPRED leads to a longer life expectancy. The increases in life expectancy of those who have suffered an acute cardiovascular event causes cardiac rehabilitation programs should bear a follow-up that can easily exceed ten years.