Table 3.

Hemodynamic values, ventilatory parameters, and cardiac function measured during submaximal and peak exercise

Variable	HF	HF, MRT ≥60s	HF, MRT <60s	Control
Submaximal Exercise
RAP, mmHg	10(8)^§	11(9)^*	8(5)	6(4)^†^‡
PAP, mmHg	40(18)^§	43(13)^*	33(20)	21±1^†^‡
PCWP, mmHg	25(15)^§	27(13)^*	19(14)	10(6)^†^‡
MAP, mmHg	90±1^§	88±1	88±6	109±1^†^‡
C[a−v]O₂, mL O₂/dL	10.7(3.4)^§	11.2(3.3)	10.2(2.8)	8.9(2.2)^†^‡
Cardiac Output, L/min	4.9(2.6)^§	4.6(1.9)^*	5.5(3.4)	8.1(2.8)^†^‡
Heart rate, bpm	84(25)	83(26)	85(25)	79(20)
PaO₂, mmHg	92±1	92±2	91±1	92(21)^‡
PaCO₂, mmHg	38(7)	37(6)^*	40(6)	36±1^‡
pH, units	7.44^§	7.44	7.44	7.43^†^‡
V_d/V_t,%	15±1^§	17±1^*	12±2	11±1^†
Work, watts	51±4	52±4	50±4	57±6
Peak Exercise
RV Ejection Fraction (peak), %	39(16)^§	37(21)^*	45(11)	58±1^†^‡
LV Ejection Fraction (peak), %	33±1^§	32±2	36±2	71±1^†^‡
Peak C[a−v]O₂, mL O₂/dL	13.6±0.4	13.7±0.7	13.6±0.5	12.8±0.3
Peak VO₂, ml/kg/min	12.4±0.6^§	11.5±0.9^*	13.5±0.9	23.0±1.5^†^‡
Work, Watts	79±7	76±8	84±8	132±10^†^‡

Continuous variables are presented as mean ± standard error of the mean (SEM) if normally distributed and as median (interquartile range) if not normally distributed. MAP indicates mean systemic arterial pressure; RAP mean right atrial pressure; PAP mean pulmonary arterial pressure; C[a−v]O₂ indicates arterio-venous difference in oxygen content (i.e. oxygen extraction); V_d indicates dead-space ventilation. Submaximal exercise values were averaged over the first 6 minutes of exercise, with the exception of work, which refers to the work rate at 6 minutes.

Indicates P<0.05 for comparison of HF, MRT >60s and HF, MRT <60s,

^†

indicates P<0.05 for HF, MRT >60s vs. controls,

^‡

indicates P<0.05 for comparison of HF, MRT <60s and controls, and

^§

indicates P<0.05 for comparison of HF and controls.