Morphological Properties of Atrial Fibrillation Waves in Patients with Left Ventricular Dysfunction—Spectral Analysis of Atrial Fibrillation Waves in Dilated Cardiomyopathy—

Introduction: Although the atrial fibrillation cycle length (FCL) is considered to shorten in persistent atrial fibrillation (AF) as a result of electrical remodeling, whether a long-term change remains in FCL in patients with left ventricular (LV) dysfunction is uncertain. Morphological properties of AF waves were analyzed in patients with dilated cardiomyopathy (DCM). Methods and Results: The study population consisted of 43 patients with persistent AF, and they were divided into a DCM group (n = 14) and a control group (n = 29). Fibrillation waves from surface ECG lead V1 were purified by subtracting the QRS-T complex template. Power spectral analysis was performed by Fast Fourier Transformation, and the mean FCL was determined by the peak power frequency in 20 epochs at each recording. The LV ejection fraction was lower in the DCM group (50 ± 18%) than the control (63 ± 8%, p = 0.001). The mean FCL was shorter in the DCM group (132 ± 14 ms) than the control (151 ± 23 ms, p = 0.007) and there was a significant correlation between the FCL and LV dimensions (p = 0.03). Conclusion: In patients with persistent AF and LV dysfunction, FCL was shorter in comparison with the control, and seemed to be influenced by LV dimensions.