Atrial refractoriness early after transcatheter aortic valve implantation TAVI in patients with severe aortic stenosis and sinus rhythm.

Background: Aortic valve stenosis (AS) is a common valvular heart disease, especially in the elderly, and is associated with a high prevalence of atrial fibrillation. Although the risk of atrial fibrillation is expected to decrease after the intervention, atrial fibrillation develops in many patients undergoing surgical or percutaneous transaortic valve implantation. We aimed to evaluate atrial refractoriness since it may play a key role in the occurrence of atrial fibrillation after transaortic valve implantation.

Methods: Seventy-nine consecutive patients who underwent TAVI between October 2021 and May 2023 were enrolled in this trial. Sixty-seven patients underwent electrophysiology study before and after TAVI. We evaluated the changes in PA and AH intervals, as well as atrial effective refractory periods.

Results: Besides the hemodynamic changes, atrial effective refractory periods increased, and atrial effective refractory period dispersion (39.8±21.6 vs. 31.1±18.0) decreased significantly after TAVI. The change in atrial effective refractory period dispersion after TAVI was correlated only with the changes in left ventricular end-diastolic pressure (r=0.77, P=0.001) and the changes in aortic gradient (r=0.4, P=0.001). The independent variables affecting the changes in atrial effective refractory period dispersion were basal pro-BNP levels, besides the changes in left ventricular end-diastolic pressure and aortic gradient after transaortic valve implantation.

Conclusions: Our results show an acute improvement in atrial refractoriness after TAVI, though high atrial fibrillation rates are reported in the literature. The timing of aortic valve replacement is important, as irreversible maladaptive changes might have already developed by the time of intervention.