[PP.09.22] PULSE PRESSURE AMPLIFICATION USING 24-HOUR AMBULATORY BLOOD PRESSURE

Objective: The blood pressure wave changes as it travels from the central elastic arteries to the muscular conduit arteries. As a consequence, in healthy subjects, the amplitude (pulse pressure, PP) of the pressure wave increases gradually from the aorta to the periphery. This phenomenon, is known as PP amplification (PPA). It is mathematically defined as the peripheral pulse pressure/central pulse pressure ratio. Until now the clinic PP was used in the nominator. Our study aimed in finding differences between these two indices using clinic and ambulatory BP measurements. Design and method: We recruited 87 drug naïve (mean age = 52.2 ± 12.5) 55 females, newly diagnosed hypertensive patients that visited the hypertension clinic of a tertiary hospital. Central systolic aortic BP (CSBP), Central diastolic BP (CDBP) was assessed by applanation tonometry and PWV was measured by Sphygmocor (Atcor Medical), 24-hour SBP and 24-hour DBP were also measured (Spacelabs 90217), and clinic SBP and DBP were measured according to international guidelines. The PPA ratio was defined as the peripheral pulse pressure/central pulse pressure and PPA 24-hour, and PPA daytime and PPA nighttime were calculated accordingly. Results: PPA was significantly correlated with PPA 24-hour (r = 0.68, p < 0.001), and PPA daytime (r = 0.67, p < 0.001) and PPA nighttime (r = 0.43, p < 0.001). However there were significant differences between the different PPAs. PPA was significantly higher than all the 24-hour indices 1.24 ± 1.8 vs 1.15 ± 2.7 for PPA 24-hour, 1.17 ± 0.27 for PPA daytime and 1.08 ± 0.48, p < 0.001 for all comparisons. Conclusions: PPA was different when ambulatory blood pressure indices were used for its calculation. PPA using 24-hour indices should be tested to investigate whether it better correlates with cardiovascular markers.