The R-Wave amplitude in V1 on baseline ECG correlates with the occurrence of high-degree atrioventricular block following left bundle branch block after transcatheter aortic valve replacement

Abstract

Abstract Aims Several procedural and ECG parameters have been associated with the occurrence of high-degree atrioventricular block (AVB) requiring permanent pacemaker implantation (PPI) after transcatheter aortic valve replacement (TAVR). We hereunder sought to assess if the baseline R-wave amplitude in V1 ECG-lead of patients with normal QRS duration undergoing TAVR is associated with a higher patient’s risk for developing high-degree AVB following left bundle branch block (LBBB). Methods and Results In this retrospective single-center study in 720 consecutive patients who underwent TAVR, 141 (19.6%) patients with normal QRS duration developed a new LBBB after TAVR. The 24 (17%) patients who underwent PPI for reasons other than high-degree AVB were excluded from further analysis. In the remaining 117 study patients, 14 (12%) developed high-degree AVB requiring PPI (Group 1) while the remaining 103 (88%) patients did not (Group 2). There were no significant differences in baseline demographic or procedural characteristics nor in PR interval, QRS duration and QRS axis between these 2 groups. The incidence of left anterior hemiblock was higher in Group 1 (3 of 14, 21.4%) than in Group 2 (9 of 103, 8.7%) but the difference was not statistically significant (p=0.156). The R-wave amplitude in V1 was smaller in Group 1 than in Group 2 (0.029±0.04mV vs. 0.11±0.14mV, p=0.0316). In the receiver operating characteristics analysis, the cutoff for R-wave amplitude pre-TAVR was 0.03mV, area under the curve=0.7219, (p=0.0002). Conclusion The R-wave amplitude in lead V1 during baseline ECG in patients with normal QRS duration may predict the occurrence of high-degree AVB following new LBBB after TAVR.Figure 1.ROC AnalysisFigure 2.Representative case