The characteristics of core parameters during cardiopulmonary exercise testing in patients with hypertrophy cardiomyopathy

Abstract

Objective: The patients with Hypertrophic CardioMyopathy (HCM), characterized by hypertrophy of the myocardium with a high risk of sudden death, was less clear for the exercise pathophysiology. Under the guidance of holistic integrative physiology and medicine (HIPM), the ramp protocol symptom-limited CardioPulmonary Exercise Testing (CPET) is the only method to evaluate the overall functional status of human body. We investigated the CPET pathophysiology in patients with HCM. Methods: From April 2017 to January 2020, 244 subjects were enrolled after signed the informed consent form and completing CPET in Fuwai Hospital. They 219 HCM patients and 25 healthy normal subjects as control (NS). The changes of CPET core parameters between two them were calculated, compared and did Individual analysis. Results: ①The gender of HCM was 163 maleand 56 female. The gender of NS was 11 male and 14 female. The age of HCM was (46.7±12.8, 16.0~71.0) year; NS was (43.7±10.4, 26.0~61.0) year.②The core CPET parameters of HCM: peak oxygen uptake (Peak VO2) was (65.2±13.8, 22.8~103.4) %pred; anaerobic threshold (AT) was (66.4±13.0, 33.7~103.5) %pred; Peak O2 pulse was (84.3±19.0, 90.9~126.0)%pred; oxygen uptake efficiency platform (OUEP) was (99.2±13.4, 69.1~155.5) %pred; Lowest VE/VCO2 was (108.0±13.2, 70.4~154.0)%pred; VE/VCO2 Slope was (108.5±17.9, 66.9~164.9)%pred. Compared with NS, the Peak VO2, AT, Peak O2 pulse, and OUEP were significantly decreased (P<0.01 or P<0.05), but the Lowest VE/VCO2 and VE/VCO2 Slope were significantly increased (P<0.05). For Individual analysis of the overall functional status of CPET, some were very sever but some HCM were still within the normal range.③ The Peak VO2 was positively correlated with AT, OUEP, Peak O2 pulse, and peak systolic blood pressure, but was negative correlated with Lowest VE/VCO2 and VE/VCO2 Slope. Conclusion: CPET is safe and specific characteristics for patients with HCM, which deserve further research and clinical application. Under HIPM guidance, CPET can not only be used for overall functional evaluation, disease diagnosis and differential diagnosis, risk stratification, curative effect evaluation and accurate prognostic prediction, but also be utilized in formulating the individualized training prescription and management of chronic diseases.