The investigators aim to investigate whether central systolic blood pressure, as measured during regular 24 hour ambulatory blood pressure monitoring (ABPM), is a better predictor of left ventricular mass than peripheral systolic blood pressure during ABPM.

It seems obvious that central blood pressures are pathophysiologically more relevant than peripheral blood pressures for the pathogenesis of cardiovascular disease: it is central systolic pressure (cSBP) against the heart ejects (afterload), and it is central pulse pressure (cPP) that distends the large elastic arteries. Indeed, cSBP and cPP have been associated more closely with left ventricular hypertrophy and carotid atherosclerosis as markers of hypertensive end-organ damage than brachial pressures in various populations. However, in these studies office blood pressure measurements have been used. As ABPM measurements per se show a closer association with hypertensive end-organ damage than office measurements, and as the investigators have recently developed and validated a novel algorithm (ARCSolver) to calculate central blood pressures from peripheral waveforms, the investigators speculate that cSBP measured during ABPM may be the best predictor of left ventricular mass.

Inclusion Criteria:

> 18 years of age,

• no intake of antihypertensive medications
• should have an indication for ABPM (suspected arterial hypertension)

Exclusion Criteria:

• no written informed consent
• left ventricular hypertrophy due to other reasons than hypertension (hypertrophic cardiomyopathy, infiltrative cardiomyopathy, valvular heart disease, congenital heart disease)
• inability to provide adequate echocardiographic readings
• segmental contraction abnormalities of the left ventricle
• contraindications for ABPM (lymphedema both arms)
• other rhythm than stable sinus rhythm
• unstable clinical condition, including recent severe infections

community sample