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Updated: Jul 7, 2026
Assessment of Pulmonary Capillary Blood Volume, Membrane Diffusing Capacity, and Intrapulmonary Arteriovenous Anastomoses During Exercise
Published on: February 20, 2017
The Predictive Value of the Combined FVC/DLCO Ratio and 1-Minute Heart Rate Recovery After Exercise in Stable Chronic
Ning Wang1, Jia Xing1, Yuqiang Zheng1
1Department of Respiratory and Critical Care Medicine, Hengshui People's Hospital, Hengshui, Hebei, 053000, People's Republic of China.
Objective:
To evaluate the predictive value of combining the pulmonary function index forced vital capacity to diffusing capacity of the lung for carbon monoxide ratio (FVC/DLCO) with 1‑minute heart rate recovery (HRR1) in stable chronic obstructive pulmonary disease (COPD) complicated by pulmonary hypertension (PH), and to develop a machine learning‑based prediction model.
Methods:
A total of 159 stable COPD patients (COPD group) and 52 stable COPD patients with PH (COPD+PH group) were enrolled. Baseline data were collected. Predictive performance of FVC/DLCO and HRR1 alone and in combination (logistic regression) was assessed. Four machine learning models (Random Forest, XGBoost, LightGBM, SVM) were trained using all features.
Results:
The COPD+PH group showed significantly higher FVC/DLCO and lower HRR1. The combined FVC/DLCO+HRR1 model achieved an AUC of 0.781 (95% CI: 0.709-0.853), outperforming either marker alone. The Random Forest model performed best (AUC = 0.923, 95% CI: 0.881-0.961; accuracy 0.892; sensitivity 0.871; specificity 0.912), with good calibration. FVC/DLCO and HRR1 were the top two predictors.
Conclusion:
Combining FVC/DLCO with HRR1 enhances predictive accuracy for PH in stable COPD. The Random Forest model shows excellent performance, but external validation is needed before clinical implementation.
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