Outcomes of TAVR in Minimally Symptomatic Aortic Stenosis
- In a retrospective cohort study using data from the STS/ACC TVT registry, 20% of patients who underwent TAVR between 2015 and 2021 were minimally symptomatic, with substantial variability between sites in the proportion of patients who underwent TAVR with minimal symptoms.
- Minimally symptomatic patients who underwent TAVR had only small improvements in health status at 30 days and at 1 year, but health status and survival were higher compared to patients with worse baseline symptoms.
- Minimally symptomatic patients in this study had fewer major cardiovascular morbidities compared to more symptomatic patients, and it might be difficult from these data to address whether TAVR should be pursued in asymptomatic patients with severe AS.
What are the outcomes associated with transcatheter aortic valve replacement (TAVR) performed in patients with minimally symptomatic aortic stenosis (AS)?
In a retrospective cohort study, the Society of Thoracic Surgeons/American College of Cardiology (STS/ACC) Transcatheter Valve Therapies (TVT) registry was used to identify patients who underwent elective TAVR between January 2015 and December 2021; excluding patients with left ventricular ejection fraction <50%, aortic valve mean gradient ≥60 mm Hg, and TAVR indication other than AS. Baseline Kansas City Cardiomyopathy Questionnaire overall summary score (KCCQ-OS) was used to distinguish patients with minimal symptoms (KCCQ-OS ≥75) from those with moderate or worse symptoms (KCCQ-OS <75). Outcomes were 30-day composite adverse events (death, stroke, major or life-threatening bleeding, stage III acute kidney injury, new dialysis, or moderate/severe paravalvular leak), 30-day death, 1-year alive and well status, 1-year death, and 30-day and 1-year health status measured by KCCQ-OS.
Among 231,285 patients who underwent TAVR between 2015–2021 (median [IQR] age 80.0 years [74.0-86.0], 47.5% female), 20.0% were minimally symptomatic prior to TAVR. Of 793 sites, minimally symptomatic patients comprised <10% of TAVRs at 123 (15.5%) sites, 10-25% of TAVRs at 465 (58.6%) sites, >25-50% of TAVRs at 194 (24.5%) sites, and >50% of TAVRs at 11 (1.4%) sites. Compared to more symptomatic patients, minimally symptomatic patients were more likely to be men and to have a lower burden of major cardiovascular morbidities including diabetes, atrial fibrillation or flutter, severe chronic lung disease, prior myocardial infarction, prior transient ischemic attack or stroke, pacemaker, and moderate/severe mitral regurgitation or tricuspid regurgitation.
The median STS predicted risk of mortality was 3.2% (IQR 2.0-4.9) in the minimally symptomatic patients and 4.2% (IQR 2.7-6.6) in the ≥ moderately symptomatic patients. Survival at 1 year was higher in minimally symptomatic patients compared to those with moderate or severe symptoms (adjusted hazard ratio [HR] for death, 0.70; 95% confidence interval [CI], 0.66-0.75). Mean KCCQ-OS increased by 2.7 points (95% CI, 2.6-2.9) at 30 days and 3.8 points (95% CI, 3.6-4.0) at 1 year in minimally symptomatic patients compared with increases of 32.2 points (95% CI, 32.0-32.3) at 30 days and 34.9 points (95% CI, 34.7-35.0) at 1 year in more symptomatic patients. Compared to more symptomatic patients, minimally symptomatic patients had higher odds of being alive and well at 1 year (odds ratio, 1.19; 95% CI, 1.16-1.23).
The authors conclude that, although minimally symptomatic patients treated with TAVR experience only small improvements in health status, their overall outcomes are favorable with a higher likelihood of survival with good health status at 1 year compared with more symptomatic patients.
The timing of intervention for severe AS should weigh the relative risks and benefits of intervention compared to continued monitoring. With accumulating data suggesting the potential for subclinical cardiac damage during an interval of ‘watchful waiting’ in patients with severe AS and with lower procedural risks associated with TAVR compared to surgical aortic valve replacement, there is reason to question whether earlier intervention using TAVR in asymptomatic patients might be warranted. This retrospective cohort study using data from the STS/ACC TVT registry found that 20% of patients who underwent TAVR between 2015 and 2021 were minimally symptomatic, that there was substantial variability between sites in the proportion of patients who underwent TAVR with minimal symptoms, that minimally symptomatic patients who underwent TAVR had only very small improvements in health status at 30 days and at 1 year but that health status was superior to those of patients with worse baseline symptoms, and that minimally symptomatic patients had higher odds of survival at 30 days and 1 year compared to patients with worse baseline symptoms.
Baseline health status is known to be a strong predictor of outcomes after TAVR. Although the authors suggest that less underlying cardiac damage among patients with fewer symptoms could have been responsible for better symptom and survival outcomes, the differences in baseline comorbidities between groups make it difficult to meaningfully compare their outcomes. Of clinical interest is whether asymptomatic patients with severe AS are likely to benefit from early intervention with TAVR. Although the ongoing EARLY TAVR (TAVR Compared to Surveillance for Patients With Asymptomatic Severe Aortic Stenosis) trial is expected to shed light on this question, the present study might instead document that healthy, asymptomatic patients remain asymptomatic and do better after TAVR compared to less healthy and more symptomatic patients.
Keywords: Aortic Valve Stenosis, Health Status, Heart Valve Diseases, STS/ACC TVT Registry, Transcatheter Aortic Valve Replacement
< Back to Listings