Abstract Body (Do not enter title and authors here):

Introduction:
Post-transcatheter aortic valve replacement (TAVR) pacemaker (PPM) implantation is a known complication. Chronic total occlusion (CTO) of coronary arteries is common in TAVR patients and is a marker of advanced coronary calcification. Its influence on the requirement for PPM post-TAVR remains unclear. We investigated the association between pre-existing CTO and the incidence of PPM post-TAVR.
Methods:
A retrospective cohort study was conducted using the National Inpatient Sample database from 2018-2020 with 205,565 patients who underwent TAVR. Propensity score matching was utilized to create a matched cohort of patients with and without CTO, balancing key variables such as age, sex, elective procedure status, and comorbid conditions (heart failure, arrhythmias, pulmonary circulation disorders, peripheral vascular disorders, and complicated diabetes). Outcomes measured included the requirement for PPM implantation post-TAVR, in-hospital mortality, and major adverse cardiac events (MACE). Weighted samples were utilized and p-value <0.05 was considered significant.
Results:
The unmatched analysis included 3,495 patients with CTO and 202,070 without CTO. Patients with CTO were likely to have comorbidities such as heart failure, arrhythmias, and complicated diabetes (Table 1). Unmatched results showed a higher incidence of PPM implantation in patients with CTO (9.2%) compared to those without CTO (7.1%) (p<0.05). Propensity score matching yielded a cohort of 6,930 patients. In the matched analysis, the incidence of PPM implantation was 9.2% in patients with CTO and 6.5% in those without CTO (p=0.06). Logistic regression analysis in the matched cohort demonstrated that CTO was associated with increased odds of PPM implantation post-TAVR (OR 1.47, 95% CI 0.99-2.18, p=0.06). In-hospital mortality and MACE did not differ significantly between the two groups.
Conclusion:
We conclude that pre-existing CTO may be associated with a higher incidence of PPM implantation after TAVR, although the difference was not statistically significant. Further research is needed to validate these findings and explore the mechanisms involved.