[Normal maximal functional capacity in patients with congestive heart failure due to Chagas' cardiomyopathy].
OBJECTIVE
To compare patients with heart failure due to Chagas' cardiomyopathy and maximal oxygen consumption greater than 20mL/kg-1/min-1 to normal individuals.


METHODS
We studied 104 male patients with heart failure due to Chagas' cardiomyopathy, functional classe II-IV, age 18 to 65 years (40.3 +/- 9.0), and 23 normal sedentary male individuals (GI) age 17 to 51 years (35 +/- 8.7). Maximal oxygen consumption (VO2max) was obtained using a Beckman metabolic measurement cart, and left ventricular ejection fraction (EF) by conventional transthoracic echocardiography. Comparisons between means were made with t-test.


RESULTS
Thirty seven patients (35.6%) presented VO2max above 20mL/kg-1/min-1 (G2), with values ranging from 20.5 to 30 (24.5 +/- 2.9) and EF between 19 and 63% (42 +/- 11.7). GI had VO2max between 21 and 42mL/kg-1/min-1 (33.3 +/- 5.6) and EF between 70 and 82% (75.1 +/- 3.2). Ages were not significantly different for the two groups (p = 0.1136). VO2max and EF were lower in G2, and this was statistically significant (p < 0.0001).


CONCLUSIONS
These results indicate that patients with congestive heart failure due to Chagas disease may show values of VO2max, greater than 20mL/kg-1/min-1 which does not mean that they have normal maximal functional capacity.
Mady
C
C
Instituto do Coração do Hospital das Clínicas-FMUSP, São Paulo.
Cardosa
R H
RH
Ianni
B M
BM
Arteaga
E
E
Koide
N S
NS
Silva
P R
PR
da Luz
P L
PL
Bellotti
G
G
Pileggi
F
F
D000293:Adolescent; D000328:Adult; D000368:Aged; D002598:Chagas Cardiomyopathy / Q000150:complications*; D005080:Exercise Test; D006333:Heart Failure / Q000209:etiology / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008451:Maximal Voluntary Ventilation / Q000502:physiology*; D008875:Middle Aged; D010101:Oxygen Consumption / Q000502:physiology; D013318:Stroke Volume / Q000502:physiology