Figure 1From: Capillary pCO2 helps distinguishing idiopathic pulmonary arterial hypertension from pulmonary hypertension due to heart failure with preserved ejection fraction Histogram showing the distribution of capillary pCO 2 in patients with idiopathic pulmonary arterial hypertension (red) and patients with pulmonary hypertension due to heart failure with preserved ejection fraction (green) in 5 mmHg intervals. Back to article page