Lack of concordance between the different exercise test measures used in the risk stratification of patients with pulmonary arterial hypertension

Abstract

In pulmonary arterial hypertension (PAH) patients it is essential to perform a prognostic assessment to optimize the treatment. The aim of this study is to evaluate the risk stratification concordance assessed with different exercise test variables in a cohort of PAH patients. A retrospective analysis was performed using patient data registered in the PAH unit. Only those patients in whom the mean time elapsed between the 6‐min walking test (6MWT) and the cardiopulmonary exercise test (CPET) was a maximum of 6 months were selected. A total of 140 records from 40 patients were finally analyzed. When it came to assessing the concordance between the two exercise tests in the guidelines (CPET and 6MWT), up to 84.3% of the records did not coincide in terms of the risk stratification. Exclusively considering the CPET parameters, most of the records (75%) failed to include all three variables in the same risk category. When analyzing the VO 2 alone, up to 40.7% of the tests yielded different risk classifications depending on whether the parameter was expressed. In conclusion, there is a low concordance between the two proposed exercise tests. These results should be a call for reflection on whether the cut‐off points set for the exercise tests proposed for the current risk stratification are adequate to achieve a correct risk stratification or whether they require an appropriate revision.

Simplified risk stratification based on cardiopulmonary exercise test: A Spanish two‐center experience

“…Young patients with PAH, and even with heart failure, can walk distances greater than 440 m in the 6MWT, and therefore obtain lower scores (distances longer than 440 m score 1 on the 4‐strata scale). In this line, a recent study demonstrated that there is a low level of concordance between the distance walked in the 6MWT and the peak VO 2 in patients with PAH, and a lack of concordance between the different CPET variables used in risk stratification 15 . The younger age of our study population, added to the distance in the 6MWT, reflects the youth and robust status of our population, which clearly depicts a ceiling effect.…”

“…In this line, a recent study demonstrated that there is a low level of concordance between the distance walked in the 6MWT and the peak VO 2 in patients with PAH, and a lack of concordance between the different CPET variables used in risk stratification. 15 The younger age of our study population, added to the distance in the 6MWT, reflects the youth and robust status of our population, which clearly depicts a ceiling effect. Hence, the CPET emerges as a useful tool for these patients.…”

Elderly Patients with Idiopathic Pulmonary Hypertension: Clinical Characteristics, Survival, and Risk Stratification in a Single-Center Prospective Registry

“…The absolute values of peak oxygen consumption and peak minute ventilation per unit of carbon dioxide were included in the risk stratification proposed by the ESC/ERS in 2015. However, these parameters have not been widely used due to their low concordance with 6MWT and the interpretation discrepancies between the absolute and predicted values [26]. We observed the comparable absolute values of peak VO 2 , oxygen pulse, and CO 2 ventilatory equivalent in two groups, while the predicted values of peak VO 2 , aerobic threshold, and VO 2 /HR were significantly lower in younger patients in comparison with patients over 60 years.…”

Elderly Patients with Idiopathic Pulmonary Hypertension: Clinical Characteristics, Survival and Risk-Stratification in a Single-Center Prospective Registry

“…The absolute values of peak oxygen consumption and peak minute ventilation per unit of carbon dioxide have been included in the risk stratification proposed by the ESC/ERS in 2015. Unless those parameters have not been widely used due to the low concordance with 6MWT and the interpretation discrepancies between the absolute and predicted values [31]. We observed the comparable absolute values of peak VO2, oxygen pulse, and CO2 ventilatory equivalent in two groups, while the predicted values of peak VO2, aerobic threshold, and O2/HR were significantly lower in younger patients in comparison with patients over 60 years.…”

“…We have not seen any differences in PVR, cardiac index and PWCP between young and elderly patients, as well as between groups with H2FpEF ≥2 and H2FpEF≤1. PCWP was almost the same for both groups (8.46±4.6 vs 8.9±4.7 mmHg, p=0.6) and was lower compared with PCWP obtained from COMPERA and Swiss registries (10±3 and 12±7 mmHg, respectively) and N. Öcal et al (2022) data [7,31,41]. The majority of patients with H2FPEF score ≥2 are treated with loop diuretics that could reduce PCWP.…”