Measurement of non-invasive cardiac output during cycling exercise in ischemic stroke inpatients: A pilot study

BACKGROUND: Cardiac dysfunction accompanies acute ischemic stroke and affects the effective implementation of early rehabilitation interventions. There is a lack of reference hemodynamic data on cardiac function in the subacute phase of ischemic stroke. OBJECTIVE: In this study, we aimed to identify appropriate cardiac parameters for exercise training utilizing a pilot study. METHODS: We used a transthoracic electrical bioimpedance non-invasive cardiac output measurement (NICOM) device to monitor cardiac function in real time for two groups [i.e., subacute ischemic stroke inpatients group (n = 10) and healthy control group (n = 11)] using a cycling exercise experiment. The parameters of both groups were compared to highlight the cardiac dysfunction in the subacute phase in patients with ischemic stroke. RESULTS: We considered stroke volume index (SVI) and systemic vascular resistance index (SVRi) as the primary outcomes, and there was significant intragroup difference (stroke group: P < 0.001; control group: P < 0.001, using one-way ANOVA) and significant intergroup difference at each individual time segment (P < 0.01, using independent t-test). Among the secondary outcomes, i.e., cardiac index (CI), ejection fraction (EF), end-diastolic volume (EDV), and cardiac contraction index (CTI), we found significant intergroup differences in CI, EF, and CTI scores (P < 0.01, using independent t-test). Significant interaction with respect to time and group were seen only in the SVRi and CI scores (P < 0.01, using two-way ANOVA). There was no significant inter- or intra-group differences in EDV scores. CONCLUSION: SVRI, SVI, and CI values highlight cardiac dysfunction in stroke patients the most. At the same time, these parameters suggest that cardiac dysfunction in stroke patients may be closely related to the increased peripheral vascular resistance caused by infarction and the limitation of myocardial systolic function.