Natural history of severe aortic stenosis in elderly heart failure patients who declined transcatheter aortic valve implantation
Authors: Hieda M , Futami S , Tanaka H , Moriyama S , Masui S , Kisanuki M , Hatakeyama K , Irie K , Yokoyama T , Fukata M , Arita T , Maruyama T , Nomura H , Akashi K 
Published: October 2022

Abstract

Background
Transcatheter aortic valve implantation (TAVI) is an established minimally invasive treatment for elderly patients with severe aortic stenosis (AS). Although it is a relatively minimally invasive procedure, many elderly patients cannot undergo TAVI due to advanced age, advanced dementia, significantly impaired ADL, or because the patient or family does not wish to undergo TAVI. In general, severe AS patients died 5 years after an angina attack, 3 years after syncope symptoms, and 2 years after heart failure symptoms. However, few studies have investigated the prognosis of elderly patients with severe AS who declined TAVI.

Purpose
This study aimed to comprehend the natural history of elderly severe AS patients who declined aortic valve intervention and identify risk factors for death in the TAVI era.

Methods
We retrospectively reviewed 2,786 echocardiographic data from our hospital between 2017 and 2021. We identified 504 patients with AS in the echocardiography database. The severe AS was defined by the following echocardiography parameters: peak aortic flow velocity ≥4.0 m/s, aortic valve mean gradient ≥40 mmHg, aortic valve area (AVA)&lt;1.0 cm2, or AVA index&lt;0.6 cm2/m2. Patients with mild and moderate AS and patients who underwent surgical or transcatheter aortic valve intervention were excluded. Eventually, 82 patients fulfilled the study criteria and were analyzed in this study. Clinical events were investigated, and Cox proportional hazards analysis was performed to elucidate risk factors for mortality.

Results
The mean age was 89±6 years, and 63 (77%) were women. AHA/ACC classification was Stage A/B/C/D: 0%/52.4%/39.0%/8.5%. As event occurrence, we detected 34 (41.5%) all-cause deaths, 41 (50.0%) major adverse cardiovascular events, 32 (39.0%) development of heart failure, 13 (15.9%) chest pain attacks, and 3 (3.7%) syncope. The time from diagnosis of severe AS to all-cause death was 227±273 days, and the 1-, 2-, and 3-year survival rates were 61.5%, 46.2%, and 36.9%, respectively. Of the heart failure-onset population, 16 (50.0%) were found to have severe AS on initial heart failure admission. The incidence of heart failure at 1, 2, and 3 years after diagnosis of severe AS was 60.1%, 56.7%, and 45.4%, respectively. The time from heart failure to death was 107±147 days. Cox proportional hazards analysis adjusted with age, sex, comorbidities revealed that dementia (HR 4.5, P=0.014) and Katz index &lt;5 (HR7.8, P=0.009) were independent risk factors for mortality.

Conclusions
Compared to the comprehension of the natural history of AS patients, the prognosis in severe AS patients who declined TAVI was extremely poor. Although the elderly patients did not have a high rate of angina attacks or syncope symptoms, probably due to their reduced ADL, the results suggest that dementia prevention and maintenance of exercise tolerance are essential since dementia and reduced ADL (Katz&lt;5) are independent risk factors for mortality.

Funding Acknowledgement
Type of funding sources: Foundation. Main funding source(s): Clinical Research Promotion Foundation Reiwa 2 Michinari Hieda