"High Normal” Blood Pressure Linked to Significant Cardiovascular Risk

A new study has found that more than 70% of patients identified as having "high-normal” systolic blood pressure as measured through traditional cuff blood pressure measurement may be at serious cardiovascular risk.

Researchers at Cambridge University (UK) and Cardiff University (UK) conducted The Anglo Cardiff Collaborative Trial (ACCT), which tracked the blood pressure of 10,613 patients with two systems; a traditional blood pressure measurement using an inflatable arm cuff, and a non-invasive central blood pressure assessment using a device called the SphygmoCor. The investigators found that more than 70% of patients with brachial systolic blood pressure in the "high normal” range (130-139 mm Hg) had central systolic blood pressures corresponding to those seen in patients with stage one hypertension (140-159 mm Hg measured brachially). Elevated central pressure was also found to be associated with an increase in cardiovascular risk factors. The findings of the study further confirm the results of the Cardioblate Atrial Fibrillation (CAFÉ) and Strong Heart studies, both of which showed that individuals with elevated central pressure were at a significantly higher risk of cardiovascular events such as heart attack, stroke, and kidney disease. In both studies, elevated central pressure in patients could not be predicted by conventional brachial blood pressure measurement. The study was published in the June 2008 issue of the journal Hypertension.

"The real significance of these findings is that central and brachial blood pressures are not the same, meaning that central pressure cannot simply be inferred from the brachial pressure measurement, but should also be assessed,” said lead author Carmel McEniery, M.D. "Current guidelines for the diagnosis and management of hypertension are based solely on brachial pressure, yet this results in a large number of individuals being mis-classified based on their central pressure, leading to sub-optimal treatment.”

The SphygmoCor, a product of AtCor Medical (West Ryde, Australia), provides tools for non-invasive assessment of the cardiovascular system and autonomic function. SphygmoCor technology is centered on a transfer function that derives the pressure wave at the ascending aorta via a patented mathematical model of the properties of the brachial artery, and provides important central data through a non-invasive recording of the pressure wave at the radial artery. Current treatment guidelines call for anti-hypertensive drug therapy for stage one hypertension whereas life-style changes only are guided in the high normal range.


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Cambridge University
Cardiff University
AtCor Medical