Repercussões imediatas da primeira sessão de quimioterapia sobre a hemodinâmica e balanço autonômico cardíaco em pacientes com câncer.

Abstract

Introduction: Chemotherapy is widely recognized for its systemic side effects, including acute repercussions on the cardiovascular and autonomic systems. Early alterations in cardiac autonomic balance can negatively influence the prognosis of cancer patients, especially as they accumulate throughout treatment. Objective: To evaluate the immediate impacts of the first chemotherapy session on hemodynamics and cardiac autonomic balance in cancer patients. Methods: A cross-sectional pilot study was conducted with 14 adult patients undergoing their first chemotherapy session. Vital signs, hemodynamic parameters, autonomic functional tests (Deep Breath Test and Orthostatic Hypotension Test), as well as HRV indices in the time and frequency domains, were measured before and after the session. Results: There was a significant reduction in heart rate and double product, with an elevation in pulse pressure and a slight increase in mean arterial pressure post-chemotherapy. Heart Rate Variability analysis revealed low RMSSD and SDNN values ​​and an elevated LF/HF ratio, suggesting sympathetic predominance and parasympathetic impairment. Autonomic tests demonstrated an adequate adaptive response to orthostatic posture, but with reduced vagal modulation in the Deep Breath test. Conclusions: The first chemotherapy session promotes measurable acute changes in autonomic cardiovascular control, with a tendency towards reduced myocardial demand and sympathetic predominance. These findings reinforce the importance of early and continuous assessments of the autonomic nervous system in cancer patients, aiming at preventive strategies and greater clinical safety during treatment.