Background: Transcatheter aortic valve implantation (TAVI) is increasingly adopted in clinical practice for treatment of severe aortic stenosis, particularly for high-risk patients unfit for surgery. However, a major complication of TAVI is high-degree AV block necessitating permanent pacemaker (PPM) implantation.
Objective: The aim of our study was to evaluate standard available demographic, clinical and imaging patient parameters to develop a risk score calculator to predict PPM implantation after TAVI.
Methods: We evaluated patients who underwent TAVI at the Royal Papworth Hospital from August 2017 to November 2020 (n=583). Patients with pre-existing PPM or implantable cardiac defibrillators (ICDs) were excluded from the analysis. Data collected comprised demographic, clinical and imaging data, including computed tomography (CT) aortic valve calcium scores and ECG parameters (pre-, intra- and post-procedural). We then collected data on all eligible cases from December 2020 to June 2021 as a validation cohort.
Results: A derivation cohort with complete data (n=446) was analysed. Forty patients (8.97%) in this cohort required PPM within 30 days of TAVI. In our logistic regression model, pre-procedural existing right bundle branch block (RBBB) (OR 6.39; p=0.002), intra-TAVI left bundle branch block (LBBB) (OR 4.65; p=0.005), intra-procedural 3rd-degree AV block (OR 9.12; p<0.001), use of temporary pacing wire (TPW) pacing (OR 10.23, p<0.001) and post-TAVI LBBB (OR 6.13, p<0.001) were independent predictors of PPM and were incorporated in our multivariate logistic regression model (Figure 1). The model demonstrated excellent discriminative ability (accuracy 0.925 and an AUC of 0.952) at predicting PPM implantation. A risk score calculator was built incorporating these five characteristics, with the aim of facilitating clinician decision making regarding PPM implantation for high-risk patients undergoing TAVI.
Conclusion: The presence of pre-TAVI RBBB, intra-procedural 3rd-degree AV block and LBBB, use of TPW pacing and post-TAVI LBBB are predictive of the need for PPM implantation within 30 days of TAVI. We aim to expand this risk score calculator to incorporate these 5 characteristics, as well as the CT aortic valve calcium score, and validate this model in a larger multicentre study. ❑