PS-C13-12: NOVEL HEMODYNAMIC INDEX OF ABPM-OBTAINED PULSE WAVEFORM; EVALUATION OF CHANGES IN CARDIAC FUNCTION BEFORE AND AFTER TREATMENT OF HEART FAILURE

Abstract

Introduction: In this pilot study, we developed the novel hemodynamic index from pulse waveform for estimation of cardiac function. We obtained volumetric pulse waveform from diastolic phase of each BP measurement by our recently developed device, a Multisensor-ambulatory BP monitoring (ABPM) device (TM-2441, A&D Co., Tokyo). This pulse waveform is divided into ejection and reflex wave. The area of ejection wave is square forward pulse wave (Sf), which is related with cardiac ejection volume. Second, amplitude measured pulse wave (Am) of the pulse waveform is a parameter defined by central and peripheral artery compliance and cuff compliance (Figure). We then calculated that Sf was divided by Am, Sf/Am, to eliminate the effect of arterial and cuff compliance from the area of ejection wave, which would indicate cardiac ejective function. Methods: We prospectively assessed the changes in Sf/Am and echocardiographic left ventricular ejection fraction (LVEF) between patients with and without improved cardiac function during treatment of heart failure (HF). We conducted twice measurements of Multisensor-ABPM in 20 patients with HF (mean ± SD age, 63.3 ± 14.1 years; male, 65%; ischemic heart disease, 15%; atrial fibrillation, 25%) at baseline (just after initial or adjusted treatments) and at follow-up (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 LVEF of ≧ 10%. We then compared the changes of Sf/Am between the two groups. Results: Improvement of Sf/Am was shown in the improved group using paired t-test (Sf/Am before, 21.4 ± 4.5; after, 25.6 ± 3.7, p = 0.004), but there was no difference in the not-improved group (Sf/Am before, 26.8 ± 3.0; after, 27.7 ± 4.0, p = 0.293). Moreover, Sf/Am was associated with LVEF in overall measurements (N = 40) (r = 0.490, p = 0.004) (Figure). The change of Sf/Am from baseline to follow-up tended to be related to the changes of LVEF (r = 0.391, p = 0.080) (Figure). Conclusion: Although the present study was conducted in a small sample, this is the first study to prospectively observe the changes in pulse waveform before and after HF treatment using new ABPM device in ambulatory setting. Our study findings might show the possibility of a new hemodynamic assessment by ABPM.