Accuracy of non-invasive blood pressure measurement in patients with atrial fibrillation

Abstract

Although the accuracy of oscillometric blood pressure (BP) measurement is not so satisfied, the BP reading is still associated with cardiovascular events and death in patients with atrial fibrillation (AF). Because the currently used auscultatory or oscillometric methods were developed on sinus rhythm (SR), these BP measurement methods were not reasonable for AF patients. It is suggested that the average of three BP readings in the AF patients is accepted in clinical, even so, high systolic BP (SBP) variability and inaccurate diastolic BP (DBP) value have been reported in AF patients. In sinus rhythm, oscillometric pressure pulses (OPPs) are spindle-like, regardless of the heart rate. However, the shape of OPP is obviously associated with frequency of ventricular rate (VR) in AF patients. When the VR is rapid, the OPP is far from a spindle-like shape. With intro-aortic BP as reference, a study demonstrated that the oscillometric SBP level significantly underestimated the intro-aortic SBP level in the AF patients with increasing VR. In clinical practice, the physician should use the average of three BP readings in the AF patients. When the mean pulse rates (PR) reported by the oscillometric BP devise is less than 90 bpm and the variation of three pulse rate <10 bpm, the oscillometric SBP readings may be clinically accepted in AF patients. It is necessary to develop a new BP measurement method for AF as the current methods in AF are not so accurate as in SR.