Effectiveness of An Impedance Cardiography Guided Treatment Strategy to Improve Blood Pressure Control in A Real-World Setting: Results from A Pilot Pragmatic Clinical Trial

Background: Hypertension is a hemodynamic-related disorder characterized by abnormalities of the cardiac output (CO) and/or systemic vascular resistance (SVR). We hypothesized that selecting antihypertensive therapy based on the hemodynamic profiles of patients could improve blood pressure (BP) control more effectively than standard care in hypertensive patients in real-world clinical practice. Methods: We conducted a pilot single-center, pragmatic randomized trial involving adults with uncontrolled hypertension who sought outpatient care at a hypertension clinic of the Peking University People Hospital, the largest teaching hospital of Peking University, in Beijing China, between December 2018 and December 2019. Participants were randomly assigned to the standard care group or the hemodynamic group in a 1:1 ratio. Impedance cardiography (ICG) was performed with all participants to measure hemodynamic parameters. Only physicians in the hemodynamic group were provided with the ICG findings of patients and a computerized clinical decision support of recommended treatment choices based on the hemodynamic profiles. The primary outcomes were the changes in systolic BP (SBP) and diastolic BP (DBP) levels at the follow-up visit 4-12 weeks after baseline. Secondary outcomes included achievement of BP goal of <140/ 90 mmHg and the changes in BP by baseline BP, age, sex, and BMI. Results: A total 102 adults (mean age was 54 (SD 14) years; 41% were women) completed the study. The mean baseline SBP was 150.9 (11.5) mmHg and mean baseline DBP was 91.1 (11.3) mmHg. At the follow-up visit, the mean SBP and DBP decreased by 19.9 and 11.3 mmHg in the hemodynamic group, as compared with 12.0 and 4.9 mmHg in the standard care group (P value for difference between groups <0.001 for both SBP and DBP). The proportion of patients achieving BP goal of <140/ 90 mmHg in the hemodynamic group was 67%, as compared with 41% in the standard care group (P=0.017). The hemodynamic group had a larger effect on BP reduction consistently across subgroups by age, sex, BMI, and baseline BP. Conclusions: An ICG-guided treatment strategy led to greater reductions in BP levels than were observed with standard care in a real-world population of outpatients with hypertension. There is a need for further validation of this strategy for improving blood pressure treatment selection. (Funded by internal research grant from the Peking University People Hospital; ClinicalTrials.gov number: NCT04715698.)