Paired 14-day ECG monitoring reveals divergent arrhythmia dynamics before and after transcatheter aortic valve implantation

Introduction Therapeutic management after transcatheter aortic valve implantation (TAVI) requires precise rhythm risk stratification. While prior studies have described arrhythmias either before or after TAVI, intra-individual data quantifying qualitative and quantitative rhythm changes across the intervention remain limited. Purpose We aimed to characterize paired arrhythmia dynamics using extended ambulatory ECG monitoring before and after TAVI. Methods Consecutive patients undergoing TAVI were prospectively enrolled if 14-day ambulatory ECG patch monitoring was available both before and after the procedure. Paired intra-individual analyses were performed to evaluate changes in arrhythmia incidence as well as quantitative parameters, including arrhythmia burden, longest episode duration, and daily episode rate. Results Paired 14-day ECG monitoring was available in 100 patients (median age 82 years [78–85], 43% female), with comparable analyzable durations before and after TAVI. Following TAVI, the incidence of high-degree atrioventricular block (HAVB) increased from 0% to 9.1% (p=0.004), accompanied by significant increases in HAVB episode rate and burden (both p=0.009). Atrial fibrillation (AF) occurrence increased from 16% to 25% (p=0.035). Among patients with AF pre- or post-TAVI, AF burden increased significantly (median 0.4% vs. 18.3%, p=0.026). However, in patients with pre-existing AF (n=16), the longest AF episode was significantly shorter after TAVI (median 179.5 h vs. 50.8 h, p=0.041), with no significant change in AF burden. In contrast, ventricular arrhythmias showed improvement in patients with pre-existing non-sustained ventricular tachycardia (NSVT, n=55). Daily NSVT episode rate decreased (median 0.2 vs. 0.1 episodes/24h, p<0.001), together with a reduction in longest NSVT episode duration (median 3.0 s vs. 2.6 s, p=0.012). Supraventricular or ventricular ectopy did not change significantly in paired analyses. Conclusion Paired extended ECG monitoring reveals divergent electrophysiological effects of TAVI. While conduction disturbances and AF increase post-procedure, NSVT frequency and arrhythmia persistence decrease in patients with pre-existing tachyarrhythmias. These findings suggest simultaneous pro-arrhythmic effects on the conduction system and potentially anti-arrhythmic effects through hemodynamic unloading, underscoring the need for individualized rhythm surveillance after TAVI.