Περίληψη:
Background: Oxygen (O-2) uptake at peak exercise (Vo(2) peak) is an
objective measurement of functional capacity in patients with chronic
heart failure (CHF) The significance of recovery O-2 kinetics parameters
in predicting exercise capacity, and the parameters of submaximal
exercise testing have not been thoroughly examined. Methods and results.
Thirty-six patients (mean age = 48 +/- 14 years) with CHF and New York
Heart Association functional class I [12], II [17], or III [7],
and eight healthy volunteers (mean age = 39 +/- 13 years) were studied
with maximal and submaximal cardiopulmonary exercise testing (CPET). The
first degree slope of O-2 uptake decay during early recovery from
maximal (Vo(2)/t-slope), and submaximal exercise (Vo(2)/t-slope)(sub),
were calculated, along with Vo(2) half-time (T(1/2)Vo(2)). Patients with
CHF had a longer recovery of O-2 uptake after exercise than healthy
volunteers, expressed by a lower Vo(2)/t-slope (0.616 +/- 0.317 vs.
0.956 +/- 0.347 l min(-1) min(-1), P = 0.029) and greater T(1/2)Vo(2)
(1.28 +/- 0.30 vs. 1.05 +/- 0.15 min, P = 0.005). Vo(2)/t-slope
correlated with the Vo(2) peak (r = 0.84, P < 0.001), anaerobic
threshold (r = 0.79, P < 0.001), and T(1/2)Vo(2), a previously
established estimate of recovery O-2 kinetics (r = -0.59, P < 0.001).
(Vo(2)/t-slope)(sub) was highly correlated with Vo(2)/t-slope after
maximal exercise (r = 0.87, P < 0.001), with the Vo(2) peak (r = 0.87, P
< 0.001) and with T(1/2)Vo(2) after maximal exercise (r = -0.62, P <
0.001). Vo(2)/t-slope after maximal and submaximal exercise was reduced
in patients with severe exercise intolerance (F = 9.3, P < 0.001 and F =
12.8, P < 0.001, respectively). Conclusions: Early recovery O-2 kinetics
parameters after maximal and submaximal exercise correlate closely with
established indices of exercise capacity in patients with CHF and in
healthy volunteers. These findings support the use of early recovery O-2
kinetics after submaximal exercise testing as an index of functional
capacity in patients with CHF. (C) 2001 European Society of Cardiology.
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Συγγραφείς:
Nanas, S
Nanas, J
Kassiotis, C
Nikolaou, C
Tsagalou, E
and Sakellariou, D
Terovitis, I
Papazachou, O
Drakos, S and
Papamichalopoulos, A
Roussos, C
