P8.08 A Method Comparison of Central Blood Pressure Measurements by Pulsecor and Sphygmocor Devices

Background Estimated aortic (or central) systolic pressure (cSBP) differs from peripheral pressure and may be a better predictor of cardiovascular events. SphygmoCor® (AtCor, Sydney, Australia) uses applanation tonometery to derive cSBP by application of a generalised transfer function to radial pulse waveforms. PulseCor® (PulseCor, Auckland, New Zealand) is a new device that estimates cSBP from suprasystolic brachial cuff waveforms. We compared blood pressures measured by both devices. Methods 30 individuals (67.2±5yrs) underwent consecutive radial (SphygmoCor) and brachial (PulseCor) waveform measures. Method comparison was performed by Bland Altman analysis in Stata 11.0. Results Measurements made by the two devices were similar (Table 1). cSBP estimated by PulseCor tended to be higher than SphygmoCor, although the difference was within the American Association for the Advancement of Medical Instrumentation (AAMI) standards (< 5mmHg and SD diff was <8mmHg). Bland Altman analysis showed no systematic bias between devices across the range of blood pressures measured. Variable PulseCor SphygmoCor Difference LOA Brachial SBP, mmHg 140.7 (13.1) 140.5 (13.0) 0.2 (1.4) −2.4, 2.9 Brachial DBP, mmHg 84.7 (9.3) 84.7 (9.3) 0.0 (0.0) 0.0, 0.0 HR, bpm 65.4 (16.1) 64.6 (14.3) 0.8 (5.7) −10.3, 11.9 Central SBP, mmHg 135.0 (12.8) 131.4 (13.0) 3.6 (4.3) −4.9, 12.0 Central DBP, mmHg 85.8 (9.5) 85.4 (9.7) 0.3 (0.7) −1.1, 1.7 DBP, diastolic blood pressure; HR, heart rate; SBP, systolic blood pressure; LOA, limits of agreement. Data are means (SD) . Conclusions PulseCor and Sphygmocor give similar estimates of central blood pressures. The slightly higher cSBP measured by PulseCor could relate to the use of brachial rather than radial pressure to calibrate SphygmoCor.