0318 : Left bundle branch block after transcatheter aortic valve implantation: incidence, predictive factors and outcome

Purpose Conduction disorders are frequent after transcatheter aortic valve implantation (TAVI). The aim of the study was to assess the incidence, the clinical impact and the predictive factors of new-onset left bundle branch block (LBBB) after TAVI. Methods Between 2010 and 2014, 198 consecutive patients underwent TAVI in our center and 156 were prospectively followed during 1 year (62 CoreValve (CV), 94 Edwards Sapiens valve (ES)). 42 patients were excluded because of a pre-existing PM before TAVI, death or surgery after TAVI. Results After 156 TAVI, 40 patients (26%) required pacemaker implantation. CV patients were more frequently implanted than ES (35% vs 19%; p=0.03). Out of 116 non-implanted patients, 53 (46%) patients presented with LBBB which persisted in 35 (30%) patients. QRS width increased +27ms in post-procedure, +21ms at hospital discharge, +15ms at 1 month, +11ms at 1 year in the whole cohort. There was no clinical nor echocardiographic difference between the LBBB group and no-LBBB group. Ischemic neurological complication were more frequent during hospitalization in the LBBB group (8.6% vs 3.7%; p=0.007). On multivariate analysis, a pre-existing incomplete LBBB (OR 4.15; IC 1.31-13.11; p=0.015) and a long pre-procedure PR interval (OR 1.023; IC 1.001-1.046; p=0.038) were predictive factors of new persistent LBBB after TAVI and a trend with CV implantation was observed (OR 2.35; IC 0.99- 5.53; p=0.051). NYHA grade was increased in the LBBB group compared to non-LBBB group at 1 (2,1 ± 0,8 vs 1,7 ± 0,6 ; p=0.006), 6 (2,21 ± 0,7 vs 1,53±0,6 ; p=0.001) and 12 months (2.2 vs 1.7, p=0.04). On univariate analysis, a pre-existing atrial fibrillation (OR 2.1; IC 1.12- 4.01; p=0.021), an initial mean aortic gradient (OR 0.78; IC 0.65-0.93; p=0.006) and new LBBB after TAVI (OR 2.06; IC 1.05-4.04; p=0.036) were predictive factors of mortality at 12 months. On multivariate analysis, LBBB after TAVI was an independent predictor of mortality (OR 3.52; IC 1.17- 10.58, p=0.025). Conclusion New-onset LBBB is frequent after TAVI and persists in a great proportion of patients. In our study, LBBB after TAVI was an independent predictor of mortality.