Cardiopulmonary exercise testing as non-invasive tool for CTEPH treatment effect assessment

Abstract

<b>Introduction:</b> Cardiopulmonary exercise testing (CPET) is an important diagnostic tool for differential diagnosis and risk stratification in pulmonary hypertension (PH) patients. <b>Purpose:</b> To estimate the possibility of CPET using as non-invasive method for CTEPH treatment effect assessment. <b>Methods:</b> 37 CTEPH patients were included: 67.5% (n=25) male, 32.5% (n=13) female. Group 1: patients after pulmonary endarterectomy (PEA) (n=13, 35%); group 2: patients after balloon pulmonary angioplasty (BPA)(n=11, 30%); group 3: CTEPH medical treatment (n=13, 35%). All patients underwent RHC, CPET before and after CTEPH treatment. <b>Results:</b> PEA was more effective than BPA, according to the mPAP decrease: 25 [24; 27] vs 35 [30; 40] mmHg, p=0.017. In all groups baseline CPET parameters correlated with RHC data: SvO₂ showed a positive correlation with VO₂peak (r=0.640, p&lt;0.05), VO₂/HRpeak (r=0.557, p&lt;0.001), PETCO₂peak (r=0.598, p&lt;0.05) and VE/VCO₂ (r=0.587, p&lt;0.001). VO₂/HRpeak, PETCO₂peak and VE/VCO₂ correlated with cardiac output (CO): r=0.555, r=-0.476, and r=0.555, respectively, p&lt;0.001. There was a negative correlation between the oxygen pulse and the PVR level: r=-0.501, p&lt;0.05. The regression analysis results confirmed the influence of CO and SvO₂ on CPET data: PETCO₂peak (R2=0,258 и R2=0.357; respectively, p&lt;0.001) and VE/VCO₂, (R2=0.227 и R2=0,343; respectively, p&lt;0.001). Reliable links between of CPET and RHC data were preserved after surgical treatment. <b>Conclusions:</b> CPET can be used as a primary tool for evaluating the CTEPH treatment effect, especially in patients without residual PH after PEA according to echocardiography. Further multicenter studies are required to evaluate this approach.