Reduced exercise capacity in patients with systemic sclerosis is associated with lower peak tissue oxygen extraction: a cardiovascular magnetic resonance-augmented cardiopulmonary exercise study

Table 3 Resting CPET and CMR metrics

	SSc	SSc-PAH	NC-PAH	Healthy Controls	p value
iVO₂* (ml/min/kg)	3.3 (2.6–4.7)	3.4 (2.9–5.0)	3.1 (1.7–5.3)	3.1 (2.6–4.2)	0.14
Cardiac index (L/min/m²)	3.1 ± 0.7^†	3.0 ± 0.8^†	3.0 ± 0.7^†	2.3 ± 0.4	0.008
avO₂*(mlO₂/100 ml)	4.3 (2.3–6.7)^†	4.3 (3.3—9.2)	4.4 (3.0–6.6)^†	5.4 (4.0–7.2)	0.007
SV index (ml/m²)	45.5 ± 7.7^†§	41.4 ± 9.7	37.3 ± 10.1	35.4 ± 7.5	0.014
HR (bpm)	69.5 ± 9.1^§	72.5 ± 9.0	80.6 ± 10.1^†	67.0 ± 13.4	0.005
RVEDVI (ml/m²)	70.2 ± 12.1	71.7 ± 13.9	69.7 ± 14.5	61.4 ± 16.2	0.21
RVESVI* (ml/m²)	24.5 (10.5–40.9)	27.7 (19.0–47.8)	29.1 (12.7–64.8)	23.6 (14.9–58.9)	0.20
RVSVI (ml/m²)	44.0 ± 7.2^†§	40.2 ± 9.4	34.9 ± 9.0	34.8 ± 7.2	0.008
LVEDVI (ml/m²)	67.7 ± 11.4^§	63.7 ± 12.9	54.7 ± 16.3	58.0 ± 9.9	0.037
LVESVI (ml/m²)	23.7 ± 8.3	22.9 ± 7.6	19.6 ± 10.5	22.8 ± 5.9	0.54
LVSVI (ml/m²)	44.1 ± 7.2^†§	40.8 ± 9.7	35.1 ± 8.8	35.3 ± 6.7	0.008
LVEF (%)	66 ± 8	64 ± 9	66 ± 10	61 ± 7	0.38
RVEF* (%)	64 (53–81)	59 (30–66)	56 (22–73)	59 (42–67)	0.10
T2* (ms)	51 (44–57)^†§	50 (47–62)^†§	48 (43–52)	46 (42–49)	< 0.001
T1 (ms)	1076 ± 44^†	1079 ± 50^†§	1043 ± 46^†	994 ± 23	< 0.001

iVO₂ oxygen consumption indexed to weight, BSA, body surface, avO₂ tissue oxygen extraction, SV stoke volume, HR heart rate, RVEDVI BSA indexed right ventricular end diastolic volume, RVESVI BSA indexed right ventricular end systolic volume, RVSVI BSA indexed right ventricular stroke volume, RVEF right ventricular ejection fraction, LVEDVI/LVESVI/LVSVI/LVEF left ventricular measurements as per RV. Normally distributed data displayed as mean ± SD. *Denotes non-normally distributed data shown as median (range). ^†Significant difference between controls and indicated patient groups. §significant difference between NC-PAH and the indicated SSc groups

ISSN: 1532-429X