Background: Wave reflection accounts for augmentation of aortic pressure, but most studies have failed to show an independent relationship between augmentation index (AIx) and cardiovascular (CV) events. We hypothesise this is because conventional pulse wave analysis does not distinguish wave pressure from that attributable to charging and recoil of the aorta.

Aim: To identify if the wave pressure integral (WPI) is differentially affected by atenolol- vs. amlodipine-based therapy and is an independent predictor of CV events in the CAFE sub-study of the ASCOT trial.

Methods: Radial pressure waveforms were acquired using Sphygmocor in 2070 subjects (63±8 yrs; 1675 male) and WPI was calculated. A total of 134 CV events accrued over a median 3.4 years of follow up.

Results: WPI was higher in the atenolol arm (786±284 vs 744±253 mmHg.s, p<0.001), despite similar brachial systolic BP (134±16 vs 134±14 mmHg, p=0.78). WPI predicted total CV events (Hazard ratio =2.5 [1.51–4.14], p<0.001), and remained significant after adjustment for age, sex, treatment, number of CV risk factors, brachial BP, central systolic pressure, central pulse pressure, AIx and heart rate. Central systolic pressure and AIx did not predict CV events.

Conclusions: Wave pressure was higher in the atenolol arm and independently predicted CV events in the CAFE study. WPI is easily calculated from the BP waveform and may have potential for optimization of therapy and risk evaluation.