Sg. Maclellantobert et al., EXERCISE TOLERANCE IN PATIENTS WITH EBSTEINS-ANOMALY, Journal of the American College of Cardiology, 29(7), 1997, pp. 1615-1622
Objectives. The purpose of this study was to identify the determinants
of exercise tolerance in patients with Ebstein's anomaly. Background.
Patients with Ebstein's anomaly of the tricuspid valve may have exerc
ise limitation that improves after surgical repair. Methods. One hundr
ed seventeen patients performed cycle ergometry for a total of 124 tes
ts (preoperative test in 76 patients, postoperative test in 23, test b
ut no operation in 18, preoperative and postoperative test in 7). Mult
iple linear regression analysis was used to identify predictors of max
imal oxygen uptake, oxygen saturation and heart rate at peak exercise,
Results. Age at the time of exercise ranged from 6 to 60 years (media
n 15). An atrial septal defect was present in 67 patients (88%) preope
ratively, Compared with the preoperative group, the postoperative grou
p had significantly higher maximal oxygen uptake (mean [+/-SD] 20.5 +/
- 7.4 vs. 25.3 +/- 7.0 ml/kg body weight per min, p = 0.006). Postoper
ative rest and exercise blood oxygen saturation was higher than that m
easured preoperatively (p = 0.0001). Six of seven patients tested befo
re and after the operation shelved improved exercise tolerance, Preope
ratively, major predictors of maximal oxygen uptake were oxygen satura
tion at rest (p = 0.01) and age (p = 0.0001). Preoperatively, the majo
r predictor of oxygen saturation at peak exercise was rest oxygen satu
ration (p = 0.0001), and major predictors of peak exercise heart rate
were rest heart rate (p = 0.01) and rest oxygen saturation (p = 0.01).
In the postoperative group, predictors of maximal oxygen uptake inclu
ded age at exercise testing, male gender and heart size. Conclusions.
Definitive operation for Ebstein's anomaly results in improved exercis
e tolerance. Before the operation, rest oxygen saturation is the major
predictor of exercise tolerance, oxygen saturation at peak exercise a
nd peak heart rate, Postoperatively, age, gender and heart size influe
nced maximal oxygen uptake. (C) 1997 by the American College of Cardio
logy.