Development and validation of equation for cardiorespiratory fitness in patients with heart failure with preserved ejection fraction
- Author:
Byambakhand BATTUMUR
1
;
Ji Eun LEE
;
Soo Hyung PARK
;
You-Jung CHOI
;
Dong Oh KANG
;
Eun Jin PARK
;
Ji Bak KIM
;
Jah Yeon CHOI
;
Seung Young ROH
;
Jin Oh NA
;
Cheol Ung CHOI
;
Jin Won KIM
;
Seung Woon RHA
;
Chang Gyu PARK
;
Eung Ju KIM
Author Information
- Publication Type:2
- From:The Korean Journal of Internal Medicine 2023;38(4):514-525
- CountryRepublic of Korea
- Language:English
-
Abstract:
Background/Aims:Cardiorespiratory fitness (CRF), as measured by maximal oxygen consumption (VO2max), is an important independent predictive factor of cardiovascular outcomes in patients with heart failure (HF). However, it is unclear whether conventional equations for estimating CRF are applicable to patients with HF with preserved ejection fraction (HFpEF).
Methods:This study included 521 patients with HFpEF (EF ≥ 50%) whose CRF was directly measured by cardiopulmonary exercise test using a treadmill. We developed a new equation (Kor-HFpEF) for half of the patients in the HFpEF cohort (group A, n = 253) and validated it for the remaining half (group B, n = 268). The accuracy of the Kor-HFpEF equation was compared to that of the other equations in the validation group.
Results:In the total HFpEF cohort, the directly measured VO2max was significantly overestimated by the FRIEND and ACSM equations (p < 0.001) and underestimated by the FRIEND-HF equation (p <0.001) (direct 21.2 ± 5.9 mL/kg/min; FRIEND 29.1 ± 11.8 mL/kg/min; ACSM 32.5 ± 13.4 mL/kg/min; FRIEND-HF 14.1 ± 4.9 mL/kg/min). However, the VO2max estimated by the Kor-HFpEF equation (21.3 ± 4.6 mL/kg/min) was similar to the directly measured VO2max (21.7 ± 5.9 mL/kg/min, p = 0.124), whereas the VO2max estimated by the other three equations was still significantly different from the directly measured VO2max in group B (all p < 0.001).
Conclusions:Traditional equations used to estimate VO2max were not applicable to patients with HFpEF. We developed and validated a new Kor-HFpEF equation for these patients, which had a high accuracy.
