Table 2. Cardiopulmonary exercise test data.

Variable	Atrial Fibrillation n=79	Sinus rhythm n=124	p-value
Exercise duration, min	9.0±3.0	10.1±3.0	0.02
6MWD, m	283±107	313±109	0.055
Rest VO2, mL/kg/min	3.1±0.6	2.9±0.8	0.049
Rest pulse pressure, mmHg	51±15	59±19	0.001
Peak RER	1.1±0.1	1.1±0.1	0.62
Peak Borg score	6.8±2.5	6.8±2.3	0.91
Peak SBP, mmHg	138±30	163±29	<0.0001
Peak DBP, mmHg	69±14	74±15	0.02
Peak pulse pressure, mmHg	69±26	89±24	<0.0001
Peak VO2, mL/kg/min	11.7±2.7	12.8±3.2	0.008
VO2 at VAT, mL/kg/min	7.2±1.8	7.7±1.9	0.07
VO2 at VAT (% of peak VO2)	62.6±9.2	60.6±8.6	0.12
% age-sex predicted VO2
Wasserman, %	63.6±14.2	68.8±16.0	0.02
Standard, %	40.4±8.6	42.8±9.6	0.11
Peak O2 pulse, mL/kg/bpm	0.11±0.03	0.12±0.03	0.07
Peak O2 pulse, mL/bpm	10.5±3.2	11.6±4.3	0.04
Peak circulatory power, mmHg*mL/kg/min	1644±588	2109±751	<0.0001
Circulatory stroke work, mmHg*mL/kg/bpm	15.5±5.7	19.4±6.1	<0.0001
Peak workload, Watts	67±29	77±32	0.03
Peak VCO2, mL/kg/min	12.8±3.3	14.1±3.8	0.01
Peak VE, L/min	43.6±12.7	47.0±16.0	0.12
VE/VCO2 slope	35.1±7.2	32.6±8.1	0.03
Chronotropic indices
Rest HR (pre-exercise)	72±12	69±14	0.14
Peak HR, bpm	109±27	111±24	0.69
Chronotropic response, bpm	37±23	42±20	0.17
Age-predicted maximal HR, bpm
Astrand formula†	147±9	154±10	<0.0001
Brawner formula‡	113±6	118±7	<0.0001
Chronotropic index
Astrand formula†	0.51±0.34	0.50±0.25	0.73
Brawner formula‡	1.10±1.08	0.92±0.61	0.19
HRR, bpm	11±15	10±9	0.51
HRR≤18bpm, n (%)	55 (73)	94 (83)	0.14

Continuous variables shown as mean ±SD; categorical variables shown as count (percentage).

HR, heart rate; HRR, absolute heart rate recovery at 1 minute post exercise; RER, respiratory exchange ratio; VAT, ventilatory anerobic threshold; VE, minute ventilation; VCO₂, carbon dioxide output; VE/VCO₂, slope of the relationship between minute ventilation and carbon dioxide output; VO₂, oxygen consumption.

^†220-age¹⁹

^‡164-[0.7*age]²⁰