Introduction: Recently new parameters derived from ambulatory blood pressure monitoring (ABPM) – morning blood pressure (BP) surge and ambulatory arterial stiffness index – have been shown to be risk markers for cardiovascular events and target organ damage. Purpose: To evaluate the relationship between morning surge, ambulatory arterial stiffness index (AASI), left ventricular geometry and diastolic function in patients (pts) with hypertension (HTN). Methods: 57 pts with HTN grades I and II, 54.2% women, age 55 ± 12 years were evaluated by echocardiography and ABPM. Left ventricular geometry was estimated by calculating left ventricular mass index (LVMI) using the Devereux formula and the diastolic function by transmitral E and A wave velocities and the E/A ratio. Morning surge was evaluated by sleep through surge (STS) and pre-awakening surge (PAS). STS was defined as morning BP (average BP during the 2 hours after awakening) minus the average values derived from three nocturnal BP centered by the lowest nocturnal value. PAS was defined as morning BP minus pre-awakening BP (average BP during the 2 hours prior to waking). AASI was obtained by subtracting from 1 the regression slope of the diastolic on systolic BP. Results: 15.8% pts had normal ventricular geometry, 56.1% concentric remodeling, 19.3% concentric hypertrophy (LVH) and 8.8% eccentric LVH. BP profile: 15.8% reverse-dippers, 42.1% non-dippers, 36.8% dippers and 5.3% extreme dippers. STS and PAS have correlated with LVMI (r = 0.36, p = 0.009; r = 0.28, p = 0.04 respectively), E velocity (r = 0.36, p = 0.02; r = 0.32, p = 0.04 respectively), E/A ratio (r = 0.40, p = 0.01, r = 0.37 ,p = 0.02 respectively).STS and PAS were higher in pts with eccentric LVH (p = 0.0007, p = 0.0001 respectively), but LVMI was not different between concentric and eccentric LVH (p = 0.61). AASI had a reverse correlation with STS (r = -0.41, p = 0.004), PAS (r = -0.48, p = 0.0003). AASI varied significantly with BP profile, the maximum values being recorded in reverse-dippers and minimum in extreme-dippers (p = 0.001). Conclusions: Morning blood pressure surge correlates with left ventricular mass index and diastolic function parameters. Ambulatory arterial stiffness index varies significantly with nocturnal blood pressure profile and correlates also with morning surge. Eccentric left ventricular hypertrophy is associated with significantly higher values of morning surge, independently of left ventricular mass index.