Written by Katrina Mountford, Medical Editor.
19th March 2018
The benefits of transcatheter aortic valve replacement (TAVR) compared with surgical aortic valve replacement (SAVR) is well established for high and intermediate risk patients. However, according to current American College of Cardiology/American Heart Association guidelines, TAVR is not indicated in low risk patients.1 Dr Waksman presented an interim analysis of data from a study that aimed to assess the safety and feasibility (TAVR) for patients with severe aortic stenosis who are at low surgical risk (Society of Thoracic Surgery [STS] scoreTM 3 %) for SAVR. The main inclusion criteria were severe aortic stenosis low risk suitable for transfemoral access with a TAVR device and a life expectancy of at least 1 year.
The device choice was at the discretion of the operator. Of 311 patients screened from a multi-centre registry, 221 were enrolled in the study, 200 in the main study (tricuspid) arm and 21 in the bicuspid arm. Due to the high interest in the low-risk population undergoing TAVR and complete enrolment of the tricuspid arm, the outcomes of the first 125 patients recruited in the study were presented. Mean age at baseline was 74.6 %, STS score at baseline was 1.9 %. General anaesthesia was performed in 19.2 %, conscious sedation in 80.8%, pre-dilatation in 79.1 %.
In terms of the primary endpoint, there was zero mortality at 30 days. There was no incidence of stroke or myocardial infarction (MI), and valve haemodynamics were excellent. Compared to studies of intermediate risk patients, these outcomes were excellent. In terms of secondary endpoints, sub-clinical leaflet thrombosis was present in low risk patients: hypo-attenuating leaflet thickening (HALT) was seen in 12.5 %, reduced leaflet motion (RELM) in 11.0 %, and hypo-attenuation affecting motion (HAM) in 9.3 %. The incidence of leaflet thrombosis was higher with antiplatelet therapy than anticoagulation. However, this was not associated with clinical events at 30 days. Dr Waksman concluded that TAVR appears to be safe and feasible in low-risk patients in the short term. Long-term follow up is required; the final data from this study is expected in autumn 2018.
- Nishimura RA, Otto CM, Bonow RO, et al., 2017 AHA/ACC Focused Update of the 2014 AHA/ACC Guideline for the Management of Patients With Valvular Heart Disease: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines, J Am Coll Cardiol, 2017;70:252-89.X