p.25 抽出テキスト

.......................................................................................................................................................................... Conversely, improvement is uncertain if the primary cause of reduced ejection fraction is scarring due to myocardial infarction or cardiomyopathy. Intervention is recommended when severe aortic stenosis is confirmed by stress echocardiography (true severe aortic stenosis; Figure 3),32 while patients with pseudosevere aortic stenosis should receive conventional heart failure treatment.142,181 The presence or absence of flow reserve (increase in stroke volume >_20%) does not appear to influence prognosis in contemporary series of patients undergoing TAVI or SAVR,182184 and although those with no flow reserve show increased procedural mortality, both modes of intervention improve ejection fraction and clinical outcomes.32,180,182

Decision making for such patients should take account of comorbidities, degree of valve calcification, extent of CAD, and feasibility of revascularization. • Data concerning the natural history of low-flow, low-gradient aortic stenosis and preserved ejection fraction, and outcomes after SAVR and TAVI remain controversial.162,165,167 Intervention should only be considered in those with symptoms and significant valve obstruction (see table of recommendations on indications for intervention in symptomatic and asymptomatic aortic stenosis and recommended mode of intervention and Figure 4). • The prognosis of patients with normal-flow, low-gradient aortic stenosis and preserved ejection fraction is similar to that of moderate aortic stenosis—regular clinical and echocardiographic surveillance is recommended.165,166,185

5.2.2 Asymptomatic aortic stenosis Intervention is recommended in asymptomatic patients with severe aortic stenosis and impaired LV function of no other cause,9 and those who are asymptomatic during normal activities but develop symptoms during exercise testing.172,186 Management of asymptomatic severe aortic stenosis is otherwise controversial and the decision to intervene requires careful assessment of the benefits and risks in an individual patient. In the absence of adverse prognostic features, watchful waiting has generally been recommended with prompt intervention at symptom onset.187 Data from a single RCT have shown significant reduction in the primary endpoint (death during or within 30 days of surgery or cardiovascular death during the entire follow-up period) following early SAVR compared with conservative management [1% vs. 15%; hazard ratio 0.09; 95% confidence interval (CI), 0.010.67; P = 0.003].188 However, subjects were selected per inclusion criteria (median age 64 years, minimal comorbidities, low operative risk) and follow-up in the conservative group was limited. Further randomized trials [EARLY TAVR (NCT03042104), AVATAR (NCT02436655), EASY-AS (NCT04204915), EVOLVED (NCT03094143)] will help determine future recommendations. Predictors of symptom development and adverse outcomes in asymptomatic patients include clinical characteristics (older age, atherosclerotic risk factors), echocardiographic parameters (valve calcification, peak jet velocity189,190), LVEF, rate of haemodynamic progression,189 increase in mean gradient >20 mmHg with exercise,172 severe LV hypertrophy,191 indexed stroke volume,158 LA volume,192 LV global longitudinal strain,26,168,193 and abnormal biomarker levels (natriuretic peptides, troponin, and fetuin- A).170,171,194,195 Early intervention may be considered in asymptomatic patients with severe aortic stenosis and one or more of these predictors if procedural risk is low (although application of TAVI in this setting has yet to be formally evaluated) (Table 6 and Figure 4). Otherwise, watchful waiting is a safer and more appropriate strategy.

5.2.3 The mode of intervention Use of SAVR and TAVI as complementary treatment options has allowed a substantial increase in the overall number of patients with aortic stenosis undergoing surgical or transcatheter intervention in the past decade.196 RCTs have assessed the two modes of intervention across the spectrum of surgical risk in predominantly elderly patients and a detailed appraisal of the evidence base is provided in Supplementary Section 5. In brief, these trials used surgical risk scores to govern patient selection and demonstrate that TAVI is superior to medical therapy in extreme-risk patients,197 and non-inferior to SAVR in high-198201 and intermediate-risk patients at follow-up extending to 5 years.202208 The more recent PARTNER 3 and Evolut Low Risk trials demonstrate that TAVI is non-inferior to SAVR in low-risk patients at 2-year follow-up.209212 Importantly, patients in the low-risk trials were predominantly male and relatively elderly (e.g. PARTNER 3: mean age 73.4 years, <70 years 24%, 7075 years 36%, >75 years 40%, >80 years 13%) whilst those with low-flow aortic stenosis or adverse anatomical characteristics for either procedure (including bicuspid aortic valves or complex coronary disease) were excluded. Rates of vascular complications, pacemaker implantation, and paravalvular regurgitation are consistently higher after TAVI, whereas severe bleeding, acute kidney injury, and new-onset AF are more frequent after SAVR. Although the likelihood of paravalvular regurgitation has been reduced with newer transcatheter heart valve designs, pacemaker implantation (and new-onset left bundle branch block) may have long-term consequences213215 and further refinements are required. Most patients undergoing TAVI have a swift recovery, short hospital stay, and rapidly return to normal activities.216,217 Despite these benefits, there is wide variation in worldwide access to the procedure as a result of high device costs and differing levels of healthcare resources.71,218,219 The Task Force has attempted to address the gaps in evidence and provide recommendations concerning the indications for intervention and mode of treatment (Recommendations on indications for intervention in symptomatic and asymptomatic aortic stenosis and recommended mode of intervention, Figure 4) that are guided by the RCT findings and compatible with real-world Heart Team decision making for individual patients (many of whom fall outside the RCT inclusion criteria). Aortic stenosis is a heterogeneous condition and selection of the most appropriate mode of intervention should be carefully considered by the Heart Team for all patients, accounting for individual age and estimated life expectancy, comorbidities (including frailty and overall quality of life, section 3), anatomical and procedural characteristics (Table 6), the relative risks of SAVR and TAVI and their long-term outcomes, prosthetic heart valve durability, feasibility of transfemoral TAVI, and local experience and outcome data. These factors should be discussed with the patient and their family to allow informed treatment choice. Downloaded from academic.oup.com/eurheartj/article/43/7/561/6358470 by guest on 07 October 2026