Background: Target heart rate in rate control strategy has been proposed by the Atrial Fibrillation Follow-up Investigation of Rhythm Management (AFFIRM) study. There is limited data on the correlation of measured heart rate at rest and during Holter monitoring.
Objective: To evaluate the proportion of achieved target heart rate between resting heart rate measuring and 24-hour Holter monitoring in patients with chronic atrial fibrillation who receive rate control strategy.
Material and Method: Patients with chronic atrial fibrillation who archived target resting heart rate under rate control strategy at Siriraj Hospital and who underwent 24-hour Holter monitoring were studied to evaluate the correlation between two methods of heart rate control.
Results: 47 patients were enrolled. Underlying cardiac conditions were as follows: hypertensive heart disease 44.7%, valvular heart disease 25%, coronary artery disease 17% and dilated cardiomyopathy 12.8%. There were 10 patients (21.3%) whose achieving target resting heart rate was not correlated with 24-hour Holter monitoring. Three patients (6.4%) underwent permanent pacemaker implantation due to sick sinus syndrome (SSS) or tachycardia-bradycardia syndrome.
Conclusion: In chronic atrial fibrillation patients that receive rate control strategy, evaluation of only resting heart rate might not be enough for long-term evaluation and treatment and 24-hour monitoring may be an additional helpful test in order to more precisely adjust medication for long-term treatment and detection of SSS.

Keywords: Rate control, Atrial fibrillation, Holter monitoring