Prolonged delays in receiving transcatheter aortic valve implantation (TAVI) after a diagnosis of severe aortic stenosis (AS) may be associated with a higher risk of hospitalisation for heart failure or all-cause mortality, a real-world, single-centre study from Japan has found.
Ayumi Omuro (Yamaguchi University School of Medicine Graduate School of Medicine, Ube, Japan) and colleagues report the findings of their retrospective observational study of the association between TAVI delayed beyond six months and clinical outcomes amongst patients with severe AS in Open Heart.
“The manuscript examines the clinical meaning of the commonly recommended six‑month surveillance interval in patients with severe aortic stenosis who initially defer or postpone intervention,” Omuro told Cardiovascular News. “Although this is a single‑centre study from Japan, we hope the findings will help clinicians better understand what ‘six months’ may represent for elderly patients, particularly in terms of frailty and non‑cardiac risks.”
The research includes data from 174 patients who underwent TAVI at Yamaguchi University Hospital between January 2021 and December 2023, all of whom met the diagnostic criteria for severe AS—defined as an aortic valve area <1cm² and either a peak aortic jet velocity ≥4m/s or a mean transvalvular pressure gradient ≥40mmHg—based on current American College of Cardiology/American Heart Association (ACC/AHA) and European Society of Cardiology/European Association for Cardio-Thoracic Surgery (ESC/EACTS) guidelines.
Patients were categorised into two groups according to the interval between the diagnosis of severe AS and TAVI, with the early intervention group—E group—made up of 100 patients who underwent TAVI within six months of a diagnosis of severe AS, corresponding to the lower end of the commonly recommended surveillance interval; the delayed intervention group—D group—comprised of 49 patients who underwent TAVI more than six months after diagnosis, exceeding the minimum recommended surveillance interval.
Baseline characteristics, including age, sex, body mass index, most comorbidities, frailty indices and echocardiographic parameters were mostly balanced between the two groups, with an overall mean age of 85.8 years. Reasons for delayed intervention amongst patients who were assigned to the D group included initial refusal of surgery, asymptomatic or mildly symptomatic status, prioritisation of treatment for other disease or clinical observation based upon the physician’s judgement.
Reporting their findings, Omuro and colleagues note that during a median follow-up of 729 days, the incidence of the primary composite endpoint was significantly higher in the D group (33%) than in the E group (16%). Causes of death differed between the groups, they note, writing that in the E group, deaths were due to cardiac causes (n=5), pneumonia (n=2), trauma (n=1) or unknown causes (n=1). In contrast, the D group had fewer cardiac deaths (n=2) but more non-cardiac deaths, including pneumonia (n=4), malignancy (n=2), age-related deterioration (n=1) and unknown causes (n=4).
Exploratory subgroup analyses stratified by aortic valve peak velocity (<4.5m/s vs. ≥4.5m/s), the early intervention group showed a consistently lower incidence of the composite endpoint across both strata. In the ≥4.5m/s subgroup, the difference reached statistical significance, whereas the <4.5m/s subgroup did not show a significant difference, the authors add.
The study team says that their findings suggest that when the interval between diagnosis and intervention exceeds six months, there is a higher observed risk of heart failure hospitalisation or all-cause mortality, the study’s primary endpoint, largely driven by higher rates of non-cardiac mortality.
“This pattern suggests that prolonged observation may coincide with a period of accumulating systemic vulnerability in elderly patients, rather than progression of valvular disease alone,” the study team writes, noting the trend in deaths in the D group attributable to non-cardiac factors. “These findings support the hypothesis that the guideline-recommended surveillance interval of six–12 months may represent a clinically meaningful period during which frailty and non-cardiac risks may become increasingly relevant.”
The authors note several limitations, including that it was a small, observational study, potentially limiting generalisability, and that the study only included patients who underwent the TAVI procedure, excluding those who may have died, deteriorated or become ineligible during the waiting period.
