Background: Central augmentation pressure (AP), an important component of central pulse pressure may be influenced by ventricular dynamics. We examined whether AP relates to time to peak systolic myocardial wall stress (MWS) independently of age, gender, body surface area (BSA), systolic blood pressure (SBP) and heart rate (HR) in subjects with a wide range of blood pressure.

Methods: We studied 133 subjects, evaluated for hypertension but otherwise free of clinically apparent cardiovascular disease aged 47.2±16.9 (mean ± SD) years with mean systolic blood pressure of 137±21 mmHg. Carotid pressure, obtained by tonometry calibrated from peripheral mean and diastolic BP, was used to calculate AP (difference between the second and first systolic peaks of the aortic waveform). MWS, a function of left ventricle (LV) pressure, myocardial wall volume and cavity volume was obtained using carotid tonometry to estimate LV pressure and 2D transthoracic echocardiographic wall tracking analysis (Tomtec).

Results: Time to peak MWS increased as AP increased: 76.0±2.4, 87.4±6.4 and 109.9±7.4 ms (means±SE) for first, second and third tertiles of AP respectively (p<0.001). After adjustment for age, gender, BSA, HR and SBP, time to peak MWS still positively associated with AP (standardized β=−0.19, p<0.001).

Conclusions: Higher AP is associated with prolonged initial ventricular contraction in generating of peak MWS, independently of age, gender, BSA, HR and SBP. These results do not determine the direction of causality between AP and ventricular dynamics but are consistent with ventricular dynamics being a determinant of AP.