Seman, Stefan (57211372897)Stefan (57211372897)SemanTesic, Milorad (36197477200)Milorad (36197477200)TesicBabic, Marija (59378579800)Marija (59378579800)BabicMikic, Lidija (58508729000)Lidija (58508729000)MikicVelicki, Lazar (22942501300)Lazar (22942501300)VelickiOkwose, Nduka C (57194427179)Nduka C (57194427179)OkwoseCharman, Sarah J (57190248908)Sarah J (57190248908)CharmanTafelmeier, Maria (55763927700)Maria (55763927700)TafelmeierOlivotto, Iacopo (7005289080)Iacopo (7005289080)OlivottoFilipovic, Nenad (35749660900)Nenad (35749660900)FilipovicRistic, Arsen (7003835406)Arsen (7003835406)RisticArena, Ross (57200663439)Ross (57200663439)ArenaGuazzi, Marco (7102760456)Marco (7102760456)GuazziJakovljevic, Djordje (23034947300)Djordje (23034947300)JakovljevicAllison, Thomas G (7102554432)Thomas G (7102554432)AllisonPopovic, Dejana (56370937600)Dejana (56370937600)Popovic2025-06-122025-06-122024https://doi.org/10.1016/j.pcad.2024.10.005https://www.scopus.com/inward/record.uri?eid=2-s2.0-85207141187&doi=10.1016%2fj.pcad.2024.10.005&partnerID=40&md5=ff76075072aba468222a63da79b6c34chttps://remedy.med.bg.ac.rs/handle/123456789/940Aim: We sought the cardiopulmonary exercise testing (CPET) parameter that most accurately reflected therapeutic efficacy in patients with hypertrophic cardiomyopathy (HCM). Methods: Well-being questionnaire, N-terminal brain natriuretic peptide measurements, echocardiography, and CPET were performed in patients with symptomatic non-obstructive HCM during phase II, randomized, open-label multicentre study, before and after 16 weeks of traditional or sacubitril/valsartan treatment. Patients were followed 36 months after the initial CPET. Primary endpoints were changes in: 1) peak oxygen consumption (VO2); 2) VO2 at anaerobic threshold (AT); 3) oxygen pulse; 4) minute ventilation (VE)/carbon-dioxide (CO2) production slope; 5) VE/VCO2 at AT (VE/VCO2_AT); 6) VE/VCO2 nadir; 7) VE/VCO2 intercept; and 8) partial end-tidal pressure of carbon-dioxide (PETCO2) change during CPET. Results: Of 115 screened patients, 61 (52 ± 14 years, 43 % women) were included. Within subject therapy effects were detected only by the VE/VCO2 intercept and PETCO2 change, whereas the differences between medical regimens were detected by differences in VE/VCO2 nadir and VE/VCO2_AT changes after the treatment. The best predictors of the change in well-being were left ventricular outflow tract maximal gradient and VE/VCO2 intercept (B = 0.41,0.36; SE = 0.16,0.30; CI = 0.14–0.79, 0.15–1.14; p = 0.006,0.016, respectively). Adverse cardiac events were best predicted by the initial VE/VCO2 nadir. Conclusion: Ventilatory efficiency parameters outperform peak VO2 in gauging therapy effects in patients with HCM. © 2024 Elsevier Inc.Cardiopulmonary exercise testingHypertrophic cardiomyopathyTherapy effectsVE/VCO₂ interceptVE/VCO₂ nadirVentilatory efficiency