Cardiopulmonary exercise test predicts right heart catheterization

Right heart catheterization (RHC) is usually required to confirm the diagnosis of pulmonary artery hypertension (PAH). As an invasive test, RHC may be associated with possible complications, so noninvasive parameters able to predict PAH at RHC would be extremely useful.

To ascertain possible correlations between cardiopulmonary exercise testing (CPET) and hemodynamic parameters at RHC indicative of pulmonary hypertension (PH).

Thirty-six consecutive outpatients with suspect of PAH underwent CPET and RHC; the intercept of ventilation (VEint) on the VE vs carbon dioxide production (VE/VCO₂ ) and VE/VCO2 slope at CPET and diastolic pressure gradient (DPG), trans-pulmonary pressure gradient (TPG), mean pulmonary artery pressure (mPAP) and pulmonary vascular resistance (PVR) at RHC were assessed and compared.

Ventilation VCO2 slope was directly related to DPG (r: .41, P: .019), TPG (r: .45, P: .01), mean pulmonary arterial pressure (mPAP, r: .36, P: .031), PVR (r: .41, P: .029), VEint and VE/VCO₂ slope inversely related to DPG (r: -.63, P < .001), TPG (r: -.67, P < .001), mPAP (r: -.68, P < .001) and PVR (r: -.5, P < .001).

In patients with suspected PAH, VEint during exercise and the VE/VCO₂ slope might provide useful information to predict results of RHC. Their correlations with PVR and with DPG may be helpful in discriminating patients with isolated postcapillary PH from those with combined postcapillary and precapillary.