Does chronic atrial fibrillation induce cardiac remodeling?

Aim: The aim of this study was to compare cardiac structure and function in patients with chronic atrial fibrillation (CAF), as opposed to patients with paroxysmal atrial fibrillation (PAF), and normal control subjects.

Methods And Results: This study included 83 patients, divided into 3 groups: group A, 32 patients with CAF for ≥6 months; group B, 29 patients in sinus rhythm with a documented history of PAF; and group C, 22 patients without history of atrial fibrillation. Patients with CAF were older (71 years vs. 64 in group B, and 64 in group C). Apart from age, groups were clinically similar. After careful clinical evaluation, comprehensive echocardiography studies were performed including cardiac chambers' size, systolic and diastolic left ventricular function. Left atrium (LA) volume index was significantly larger in CAF than PAF and control patients: 39 ± 13 versus 34 ± 9 versus 25 ± 8 (P < 0.003). Left ventricular ejection fraction was lower in CAF: 53.8 ± 7 versus 61.6 ± 6.7 versus 58.4 ± 5.2% (P < 0.001). Isovolumic relaxation time was shorter in CAF, 65 ± 16 versus 82 ± 21 versus 81 ± 13 msec (P < 0.001). E/Vp was significantly greater in CAF 2.6 ± 0.8 versus 1.7 ± 0.4 versus 1.7 ± 0.5 (P < 0.001). Additional diastolic parameters were also significantly different.

Conclusion: These findings demonstrate that in patients with CAF structural and functional cardiac changes occur. Patients with CAF as opposed to both normal subjects and patients with PAF have larger left atria and reduced systolic and diastolic left ventricular function.