[Ergospirometry as a method for predicting the clinical course of ischemic, Chagas and idiopathic myocardiopathy].
PURPOSE: To compare and evaluate the modifications variables obtained through spyroergometry in groups of patients with ischemic cardiomyopathy (IS), Chagas' disease (CH), and idiopathic cardiomyopathy (ID). To study tolerance to anaerobic conditions of patients from the above groups who died. METHODS: A study was carried with 50 male patients, 10 of which were found in normal conditions whereas 40 presented cardiomyopathy with compensated heart failure. We observed that from the 40 patients from the cardiomyopathy groups, nine died, subgroups OB--during the study period of 1.005 days. These were compared to subgroups NOB--the remaining 31 patients. These patients were evaluated under 4 conditions--Rest (Rep), anaerobic threshold (LA), power peak of the exercise (P) and in the fourth minute recovery (REC). The investigation was based on data collected by means of spyroergometry: oxygen consumption (MET), production of CO2-(VCO2), respiratory equivalent of oxygen (VE/VO2), oxygen pulse (VO2/FC) and the time elapsed between LA and P. RESULTS: There were significant differences when the three pathological groups (IS, CH, ID) were compared with the control groups (N). There were no significant differences when the three pathological groups compared among themselves. In relation to tolerance to anaerobic conditions significant differences were found among the patients of subgroup OB--1.33 min--who died when compared to subgroup NOB--3.26 min (time elapsed between LA and P). CONCLUSION: The authors conclude that the variables studied, obtained through spyroergometry may indicate important data towards the prognosis with heart failure.