How to evaluate BP measurements using the oscillometric method in atrial fibrillation: the value of pulse rate variation

Abstract

An oscillometric device is recommended for blood pressure (BP) measurement in atrial fibrillation (AF), but there is still controversy concerning its accuracy. Therefore, evaluation of BP values in AF patients remains a challenge. This study included 251 patients with AF and 154 participants with sinus rhythm (SR). Pulse rate (PR) and BP were measured using an oscillometric device three times. The differences between the highest and lowest PR and the systolic and diastolic BP (SBP and DBP) were calculated as ΔPR, ΔSBP and ΔDBP, respectively. AF patients were stratified with respect to ΔPR in 0-5, 6-10, 11-15 and >15 subgroups. The AF group had a greater ΔPR (12.1±8.6 vs. 4.10±3.21 b.p.m., P<0.001), ΔSBP and ΔDBP than the SR group at similar SBP and DBP. A positive correlation existed between ΔPR and ΔSBP (r=0.255, P<0.001) in AF patients, but no correlation was found in SR subjects. Meanwhile, the ΔSBP in the 0-5 and 6-10 subgroups (9.58±5.61 and 10.67±6.77 vs. 8.45±5.25 mm Hg, nonsignificant) was similar to the SR group, whereas ΔSBP in the 11-15 and >15 subgroups was significantly greater than the SR group. Regardless of ΔPR, the ΔDBP in the AF group was significantly greater than that of the SR group. The AF patients who exhibited greater variability in their PR also had a greater variability in their SBP readings. The SBP measurement for AF patients is accurate as the measurement for patients with SR if the ΔPR is of 0-10 b.p.m. in AF.