Background: Central blood pressure (BP) may be more predictive of cardiovascular events than brachial BP. A cuff-based ambulatory central BP monitor is now available; the aim of this study was to compare values of central BP between this device and the SphygmoCor device.

Methods: Two studies were conducted. Study 1: We compared seated central systolic BP (cSBP) and pulse pressure (cPP) between the Mobil-o-graph and SphygmoCor devices. Study 2: We compared cSBP and cPP between the Mobil-o-graph and SphygmoCor devices at rest and during light bicycle exercise, corresponding to approximately 12 and 25 watts.

Results: Study 1 contained 51 healthy subjects (mean age 51±20yrs, 31 females) and study 2 contained 20 subjects (mean age 43±11yrs, 9 females).

Study 1:The mean difference between devices was 1±5mmHg, P=0.18 (cSBP) and 0±4mmHg, P=0.54 (cPP). There was a strong correlation between devices for cSBP (r=0.94, P<0.0001) and cPP (r=0.92,P<0.0001).

Study 2:The mean difference in cSBP between devices was 1±3mmHg at rest and 1±6mmHg at the highest workload. The mean difference in cPP between devices was 0±3mmHg at rest and 0±6mmHg at the highest workload. The devices were strongly correlated at rest (r=1.00, P<0.0001, cSBP) and (r=0.87, P<0.0001, CPP) and at the highest workload for (r=0.94, P<0.0001, cSBP) and (r=0.85, P<0.0001, cPP).

Conclusion: Non-invasive measurement of central BP by the mobilograph device is in good agreement and highly correlated with the widely used SphygmoCor device, both at rest, and in response to light exercise simulating everyday activities during which ambulatory BP measurements might be made.