The management of patients with severe, symptomatic aortic stenosis is changed by Transcatheter aortic valve replacement (TAVR). In several randomized clinical trials the use of TAVR in intermediate to high-risk patients has been validated. Recent studies using newer generation devices have demonstrated the noninferiority of TAVR as compared with surgical aortic valve replacement in low-risk patients, supporting the increased utilization and expansion of TAVR.
Stroke can have potentially devastating consequences, including higher 30-day and 1-year mortalities. Intermediate- and low-risk patients, incorporating independent routine pre- and post-procedure neurologic evaluation, demonstrated lower stroke rates after transfemoral TAVR.
PVR is a common complication of TAVR and is a product of malapposition or insufficient contact of the circular transcatheter valve prosthesis to the often eccentric and calcified aortic annulus. Several mechanisms play a role in the incidence and severity of PVR, such as heavy localized calcification, undersizing of the prosthesis, incorrect positioning of the THV, and acute aorta-LVOT angle affecting the proper seating of the THV.
Conduction disturbances requiring permanent pacemaker implantation occur more frequently after TAVR, particularly when self-expanding or mechanically expandable valves are used. Permanent pacemaker implantation exposes patients to specific complications, such as infections, lead fractures, vein thrombosis, endocarditis, and secondary tricuspid regurgitation. Continuous right ventricular pacing may not be innocuous.
The use of TAVR in low-risk patients has important implications and requires a multifaceted approach that includes a highly functional multidisciplinary heart team for careful patient selection; a need to understand and help mitigate certain key complications, such as stroke, paravalvular regurgitation, and conduction disturbances; careful data collection for continual outcome assessment and improvement; and the necessary expertise and procedural volume to maintain excellent outcomes and ensure optimal clinical care pathways.