BLOOD PRESSURE MONITORING METHODS IN PATIENTS WITH ATRIAL FIBRILLATION: DIAGNOSTIC AGREEMENT AND ASSOCIATION WITH CAROTID ATHEROSCLEROSIS

Objective: Blood pressure (BP) measurement in atrial fibrillation (AF) is problematic with uncertain recommendations regarding the oscillometric method. This study investigated the diagnostic agreement between BP monitoring methods using the automated method [office (OBP), home (HBP), ambulatory (ABP)], and their relationship with indices of carotid atherosclerosis, in individuals with permanent AF. Design and method: Adults with AF underwent OBP (triplicate measurements, Microlife WatchBP Office), 24 h ABP (measurements at 20 minutes intervals, Microlife WatchBP03), HBP (duplicate morning/evening measurements for 7 days, Microlife WatchBP Home-N) measurements. Participants were also subjected to carotid ultrasonography for determination of carotid plaque score (CPS) from summing the thickness of all plaques in the bilateral bulbs, common and internal carotid arteries. Hypertension was defined as OBP >=140/90 mmHg, HBP >=135/85 mmHg and ABP >=130/80 mmHg for untreated patients, whereas for treated patients uncontrolled BP was defined as OBP >=130/80 mmHg, HBP >=130/80 mmHg, ABP >=125/75 mmHg. Results: Data from 26 participants were analyzed (mean age [SD] 75±7.3 years, 73% men, body mass index 30.2±5.3 kg/m2, 19% cardiovascular disease, 73% treated hypertension). Average OBP was 122.8±15.3/76.6±9.5 mmHg, HBP 127.7±16.8/80.1±12.1 mmHg and ABP 116.9±11.8/72.7±9.6 mmHg (systolic/diastolic, p<0.05 for between methods comparisons). Strong correlation was observed between all BP measurement methods (HBP vs ABP r= 0.70/0.72, OBP vs ABP r=0.80/0.82, OBP vs HBP r=0.80/0.83, systolic/diastolic, all p<0.01). Moderate agreement in diagnosing hypertension (or uncontrolled BP in treated patients) was found between HBP with ABP (77%; kappa=0.54), and substantial between OBP with ABP (88%; kappa=0.75), as well as between OBP with HBP (88%; kappa=0.77). Only nighttime pulse pressure (PP), assessed with ABP monitoring, showed significant correlation with CPS (r = 0.4, p< 0.05), whereas there were no other associations for the other BP measurements. Conclusions: These preliminary findings indicate that in individuals with AF, all BP measurement methods using automated monitors have strong correlation and satisfactory agreement, and therefore can be used as suggested in the general hypertensive population. Moreover, nighttime ABP seems to be associated with carotid atherosclerosis which is reassuring for its clinical relevance.