Risk stratification of patients with LBBB after TAVI: an international multicentric comparative study of a novel, simplified ECG algorithm and current ESC-ECG-criteria

Background Managing left-bundle-branch-block (LBBB) following transcatheter aortic valve implant (TAVI) is challenging. The European Society of Cardiology (ESC) guidelines recommend electrophysiological (EP) testing in LBBB patients meeting certain electrocardiographic (ECG) criteria. Objective to develop a novel, simplified ECG algorithm for the prediction of infranodal conduction delay in LBBB patients after TAVI and compare it to current ESC-ECG criteria. Methods We performed a international multicenter analysis of prospectively enrolled patients undergoing EP testing for LBBB after TAVI. A novel algorithm was developed by testing various combinations of the PR interval, QRS duration pre- and post-TAVI, as well as changes in these parameters for the identification of patients with infranodal conduction delay, defined as His-to ventricular (HV) interval ≥ 70 ms. The performance in predicting a HV interval ≥ 70 ms of the novel algorithm was then compared to that of the established ESC-ECG criteria. Results 769 patients with LBBB after TAVI underwent risk stratification using EP testing at seven institutions (mean age 82 ± 7 years, 55% women, 21% HV ≥ 70 ms). A novel, simplified ECG algorithm showed a sensitivity of 88% and an NPV of 92% for the rule-out of infranodal conduction delay (PR interval post-TAVI <190 ms OR QRS duration post-TAVI <160 ms) and a specificity and PPV of 85% and 41%, respectively, for the rule-in of infranodal conduction delay (PR interval post-TAVI ≥190 ms AND QRS duration post-TAVI ≥160 ms). In comparison, the ESC-ECG criteria had a sensitivity of 72%, NPV 88%, specificity of 53%, and PPV of 28%. Conclusion A novel, simplified ECG algorithm showed improved performance for the rule-out and rule-in of infranodal conduction delay compared to current ESC-ECG criteria.