PS-C13-13: BLOOD PRESSURE REACTIVITY AGAINST PHYSICAL ACTIVITY “ACTISENSITIVITY” EVALUATED BY MULTISENSOR-ABPM CHANGES BEFORE AND AFTER TREATMENT OF HEART FAILURE

Abstract

Introduction: The pathological significance of blood pressure (BP) variability in patients with heart failure (HF) has not been fully elucidated. We propose the term Actisensitivity to describe such BP reactivity in response to physical activity; this new aspect of BP variability can be evaluated using our recently developed device, a multisensor-ambulatory BP monitoring (ABPM) device (TM-2441, A&D Co., Tokyo) equipped with an actigraph that can detect physical movements. Methods: In the present study, actisensitivity is defined as the slope of the regression line that is calculated from ambulatory systolic BP (SBP) with the log-transformed value corresponding 5-min average of physical activity just before each BP measurement. We prospectively assessed the changes in actisensitivity and ambulatory BP (ABP) parameters between patients with and without improved cardiac function during the treatment of HF. We assessed 20 patients with diagnosed HF (mean ± SD age, 63.3 ± 14.1 years; male, 65%; ischemic heart disease, 15%; atrial fibrillation, 25%) just after initial or adjusted treatments, and reassessed the multisensor-ABPM data at follow-up from 6–12 months after tailored treatment. Second, we divided these patients into an improved (n = 11 patients) and a not-improved (n = 9) cardiac-function group; an increase in echocardiographic left ventricular ejection fraction of ≧ 10%. We then compared the changes in actisensitivity and ABP parameters between the two groups. Results: Parameters of ABP variability, i.e., SD, coefficient of variation, and average real variability of SBP, did not change between baseline and follow-up in either group. However, the actisensitivity value tended to increase from baseline to follow-up in the improved group (1.0 ± 3.5 vs. 4.5 ± 3.5, p = 0.065), but not in the not-improved group. The degree of changes in actisensitivity from baseline to follow-up tended to be higher in the improved group than the not-improved group (3.5 ± 5.6 vs. -1.2 ± 4.8, p = 0.059) (Figure). Moreover, in the overall patient group, the change of actisensitivity from baseline to follow-up was significantly related to the changes of LVEF (r = 0.553, p = 0.011). Conclusion: To our knowledge, this is the first study to prospectively observe the changes of novel BP reactivity against physical activity in HF patients using the new multisensor-ABPM device. Our findings should help to elucidate the relationships between BP variability/hemodynamics during physical activity and cardiac function in patients with HF.