Performance of the AM-5600 blood pressure monitor: comparison with ambulatory intra-arterial pressure.

The AM-5600 is a new device that simultaneously monitors electrocardiogram (ECG) and noninvasive blood pressure (BP) over a 24-h period. BP readings (Korotkoff sounds and cuff air pressure) are stored into the recorder, allowing the removal of BP artifacts after a visual check. In 12 subjects with essential hypertension, we compared BP values simultaneously provided by the AM-5600 and intra-arterial recordings. At rest, noninvasive systolic BP (SBP) values were lower (5.4 +/- 4.9 mmHg) and diastolic BP (DBP) values were higher (7.3 +/- 7.3 mmHg) than were intra-arterial values. In ambulatory conditions (9 subjects), between-method discrepancies were +0.8 +/- 6.1 and +12.2 +/- 7.4 mmHg for 24-h SBP and DBP, respectively. AM-5600 underestimated 24-h intra-arterial SBP and DBP SD, but it accurately tracked intra-arterial SBP and DBP changes. Editing removed 22.1% of total readings, slightly reducing between-method discrepancies. Thus the AM-5600 provides an accurate average estimate of resting and ambulatory SBP and, for DBP, a less accurate estimate that is slightly improved by editing. The AM-5600 allows accurate description of SBP and DBP profiles and thus may be suitable to describe the abrupt BP changes accompanying a number of clinical events.