Article

While cardiopulmonary exercise testing (CPX) assessment is generally
regarded as an optimal means to assess functional capacity in heart failure (HF)
patients, strength parameters are omitted. CPX indices collected in recovery may
provide additional insight regarding function, including strength. DESIGN AND
METHODS: We performed a cross-sectional controlled study. Systolic HF patients
(aged >/= 50 years) and age-matched controls were assessed using CPX and strength
evaluations. Standard CPX indices were assessed during exercise (peak oxygen
consumption [VO2], first ventilatory threshold [1stVT], and ventilatory
efficiency [VE/VCO2 slope]) as well as indices at 1-minute recovery (1 min VO2, 1
min VE/VCO2, and 1 min heart rate recovery [HRR]) and differences between peak
and 1-minute recovery (DeltaVO(2) and DeltaVE/VCO(2)). Lower extremity strength
was evaluated using the 1-repetition maximum (1RM) and power. RESULTS: Seventy
adults (31 HF; 39 controls), mean age 66.2 +/- 9.7 years were evaluated. Peak VO2
(15.4 +/- 4.2 versus 23.4 +/- 6.6 mlO(2).kg(-1).min(-1), p < 0.0001) and 1stVT
(10.9 +/- 2.1 versus 14.4 +/- 4.0 mlO(2).kg(-1).min(-1), p < 0.0001) were
diminished in HF versus controls and VE/VCO2 slope was increased (42.3 +/- 12.2
versus 35.4 +/- 8.3, p < 0.01). HF patients had reduced 1 minVO(2) (13.1 +/- 2.9
versus 16.3 +/- 3.7 mlO(2).kg(-1).min(-1), p < 0.0001), 1 min HRR (6.7 +/- 11.4
versus 12.4 +/- 7.6 beats, p < 0.02), and DeltaVO(2) (2.43 +/- 2.3 versus 7.3 +/-
5.0 mlO(2).kg(-1).min(-1), p < 0.0001) as well as increased 1 min VE/VCO2 (37 +/-
7.5 versus 31.5 +/- 4.4, p < 0.001) and DeltaVE/VCO(2) (1.17 +/- 3.0 versus -0.5
+/- 1.3, p < 0.0001). Strength parameters were relatively lower in HF. While CPX
exercise parameters correlated with strength, stronger correlations were observed
between CPX recovery parameters and strength. CONCLUSIONS: CPX recovery indices
corroborate disease-specific aerobic differences and distinguish differences in
strength. Recovery ventilatory efficiency enhances CPX's value as a comprehensive
physical function tool.

Langue : ANGLAIS