Relation of Left Ventricular Fractional Shortening to Needfor Permanent Pacemaker After Transcatheter AorticValve Implantation

Abstract

Transcatheter aortic valve implantation (TAVI) can potentially alter conduction system function due to the mechanical force applied to the conduction system by the proximal edge of the valve, particularly the CoreValve. Some reasons for post-TAVI advanced atrioventricular block have been identified. We investigated whether the degree of the motion of the basal left ventricular (LV) walls impacted the development of advanced atrioventricular block post-TAVI. A total of 407 patients (82.1 ± 6.2 years) without prior permanent pacemakers (PPMs) underwent TAVI using CoreValve (70%) or Edwards-SAPIEN (30%) prosthetic devices. The LV fractional shortening (FS) of the basal segments was measured in each patient, and the association between FS and PPM requirement, or new-onset left bundle branch block (LBBB) was evaluated. During hospitalization, 64 patients (15.7%) required PPM implantation, and 128 patients (31.4%) required PPM implantation or developed new LBBB. Independent predictors of PPM implantation included preprocedural right bundle branch block, CoreValve prosthetic device, valve implantation depth, and FS. Patients with high FS (≥40%, upper tertile) had a 2.5-fold increased risk of PPM implantation (p = 0.004) and a 1.8-fold increased risk of PPM or new LBBB (p = 0.020). Every 10% increment in FS was consistently associated with an adjusted 42% increased risk of PPM implantation (p = 0.015) and with an adjusted 43% increased risk of PPM implantation or new LBBB (p = 0.005). Thus, in our cohort, LV FS was independently associated with the need for PPM implantation during hospitalization. Hence, this simple echocardiographic measure can be used to identify patients who are at risk after TAVI.