RESUMO
BACKGROUND: Due to large beat-to-beat blood pressure variation the use of 24-h ambulatory blood pressure monitoring in patients with atrial fibrillation has been questioned. METHODS: Repeatability and variability of 24-h ambulatory blood pressure (Accutraccer II or Diasys Integra), and daily blood pressure variation was examined in 42 patients aged 51-81 (median 73.5) years admitted for elective electrocardioversion of atrial fibrillation. RESULTS: Before cardioversion 24-h ambulatory systolic blood pressure was slightly lower and nocturnal blood pressure reduction was larger in the group of patients who achieved sinus rhythm than in the group who maintained atrial fibrillation (11.5/10.5 versus 4.1/4.7 mmHg; P < 0.05). No statistically significant change was observed in ambulatory blood pressure after cardioversion in any of the two groups. Blood pressure variability (SD/mean) was 10-14% both in patients with and without conversion to sinus rhythm. Coefficient of repeatability (2 SD of difference) was 13.6 mmHg (16.6%) for diastolic blood pressure and 30.2 mmHg (24.7%) for systolic blood pressure in patients with normalized heart rhythm and 17.0 and 29.0 mmHg (21.5 and 22.4%) in patients with maintained atrial fibrillation, respectively. CONCLUSION: Ambulatory blood pressure monitoring provides data with similar variability and repeatability in patients with atrial fibrillation as in subjects with normal cardiac rhythm. Twenty-four-hour ambulatory blood pressure measurement is applicable in atrial fibrillation in the same way as during sinus rhythm.