Arterial blood pressure (BP) can be decomposed as the sum of reservoir (Pres) and excess (Pexc) pressure. Pres is constant along the arteries and results in the minimum left ventricular (LV) hydraulic work, while Pexc is linked to the excess work of the heart. We evaluated the relationship of Pres and Pexc with cardiac structural features in hypertension

Methods: 446 never-treated hypertensives (mean age 48±11 years, 62% men, BP 148/92±16/10 mmHg) were evaluated through echocardiography, radial applanation tonometry (SphygmoCor) and 24-h ambulatory BP monitoring (SpaceLabs).Amplitudes and areas of Pres and Pexc were calculated using proprietary algorithms based on central pressure curves.LV hypertrophy was defined as LV mass >51 g/m2.7. Relative wall thickness (RWT) was expressed as: 2 x posterior wall thickness/LV diameter, and concentric geometry as: RWT>0.43

Results: Pexc and Pres were correlated with LV mass (r= 0.15 and 0.17, respectively; both p<0.01) and RWT (r=0.16, p<0.01; r=0.11, p=0.02). After adjustment for age, sex, body mass index and 24-h systolic BP, subjects with LV hypertrophy had higher Pexc (18.4±10.3 vs 17.0±5.4 mmHg, p=0.02), but not Pres (39.8±12.6 vs 37.5±24.2 mmHg, p=0.09). In a multivariate model adjusting for multiple cardiovascular risk factors and other confounders, an increased Pexc independently predicted both LV mass (β=0.08, p=0.04, multiple R=0.58) and RWT (β=0.10, p=0.02, multiple R=0.40), while these relationship were not observed for Pres

Conclusions: LV mass and RWT are linearly and independently associated to Pexc, but not to Pres in untreated hypertension. Structural cardiac abnormalities may be related to an increase in Pexc