Cardiopulmonary exercise testing for treatment effect assessment in chronic thromboembolic pulmonary hypertension patients.

Aim      To determine possibilities of the cardiopulmonary stress test (CPST) as an unbiassed, noninvasive method for evaluation of the effect of managing patients with chronic thromboembolic pulmonary hypertension (CTEPH).Material and methods  This study included 37 patients with CTEPH, 24 men (mean age, 53±15 years) and 13 women (mean age, 58±8.5 years). The diagnosis was verified and theCoperability was assessed according to 2015 European Society of Cardiology Clinical Guidelines for the Diagnosis and Treatment of Pulmonary Hypertension (PH). The surgical treatment was used in 65 % (n=24) of CTEPH patients: the group with pulmonary thromboendarterectomy constituted 35 % (n=13); the group with balloon pulmonary angioplasty 30% (n=11); and the conservative tactics was used in 27 % (n=10) of patients.Results Baseline CPST parameters significantly correlated with parameters of right heart catheterization (RHC): mixed venous oxygen saturation (SvO2) significantly positively correlated with V´O2peak (r=0.640, p<0.05), V´O2 / heart rate (HR) (r=0.557; p<0.001), PETCO2 peak (r=0.598, p<0.05), and V´E / V´CO2 (r=0.587; p<0.001); cardiac output (CO) correlated with V´O2 / HR (r=0.555, p<0.001), PETCO2peak (r= -0.476; p<0.05 and r=0.555, p<0.001 for ´E / V´CO2). In repeated testing, the physical working capacity (V´O2peak) increased only in patients after the surgical treatment of CTEPH. Importantly in this process, significant correlations remained between a number of CPST and RHC parameters: SvO2 correlated with V´O2peak (r=0.743; p<0.05), V´O2 /HR (r=0.627; p<0.001), PETCO2peak (r=0.538; p<0.05), and V´E / V´CO2 (r=0.597; p<0.001); V´O2 / HR, PETCO2peak, and V´E / V´CO2 significantly correlated with CO (r=0.645, p<0.001; r= -0.516, p<0.001, and r=0.555, p<0.001, respectively.Conclusion      CPST can be used as a noninvasive instrument for evaluation of the effect of CTEPH treatment, particularly in the absence of echocardiographic data for residual PH.