Increased augmentation index of the radial pressure waveform in patients with paroxysmal atrial fibrillation

Objective: The augmentation index, a marker of wave reflection, has been reported to reflect vascular properties and to determine left ventricular (LV) characteristics. We investigated the relationship between the augmentation index and paroxysmal atrial fibrillation (AF). Methods: A total of 244 outpatients (122 patients with paroxysmal AF and 122 age-, and gender-matched controls without paroxysmal AF) were examined during sinus rhythm. The augmentation index was calculated from the radial arterial waveform using applanation tonometry methods. Results: After adjusting for age, gender, heart rate, and medications, the augmentation index was significantly higher in patients with paroxysmal AF than in subjects without paroxysmal AF (means ± SE: 88.9 ± 1.0 and 81.8 ± 1.0%, respectively; p < 0.001). In all subjects, an increase in the augmentation index was significantly correlated with LV hypertrophy and left atrial enlargement. Multiple logistic analysis revealed that an increase in the augmentation index was significantly related with paroxysmal AF, and the adjusted odds ratio of paroxysmal AF was approximately 1.8 for each 10% augmentation index increase (p < 0.01). Conclusion: An increase in the augmentation index was independently associated with paroxysmal AF. This result suggests that enhanced wave reflection may be related to the development of AF.