Factors That Prevent Progression to Transcatheter Aortic Valve Implantation (TAVI)

Abstract

Transcatheter aortic valve implantation (TAVI) is increasingly used for intermediate- and high-risk patients with severe symptomatic aortic stenosis (AS). However, safe undertaking of the procedure may be precluded by various anatomic factors. This study sought to identify prevalence of factors that prevent progression to TAVI. TAVI candidates with severe AS undergoing workup coronary angiography and iliac vessel angiography (±cardiac-gated CT) were identified and factors precluding TAVI were reviewed retrospectively from a single-centre cardiac database over a 10-year period. 197 patients were included; mean age was 81.5±6.5years (±SD); 46.2% were male. 26.9% of TAVI candidates could not proceed to femoral access TAVI due to various factors including unsuitable peripheral vasculature (13.2%), untreated coronary artery disease (CAD) deemed high risk for TAVI (8.1%), unfavourable aortic characteristics (4.1%), and low-lying coronary ostia (1.5%). Factors associated with unsuitable femoral vasculature included female gender (p<0.01) and any CAD (p=0.03). Factors associated with the presence of unrevascularised CAD included male gender (p<0.01), estimated glomerular filtration rate (eGFR)<30mL/min/1.73m2 (p=0.02), history of CAD (p<0.01), while prior percutaneous coronary intervention (PCI) or bypass surgery were protective (both p<0.01). Rates of progression to TAVI have increased over the last 10 years (p<0.01) from 58.3% prior to 2012 to 83.7% in 2016 and 2017, while incidence of unsuitable peripheral vasculature preventing TAVI (p=0.01) and CAD deemed unsuitable for TAVI (p=0.04) have both decreased. Non-progression to TAVI among higher risk patients with severe AS has become less common over the last 10 years with improvements in operator experience, lower profile devices, and wider ranges of valve sizes.