In a cohort of 827 patients undergoing TAVI, unsupervised clustering of AI-assessed echocardiographic parameters identified two distinct phenotypes among the 35% with paradoxical low-flow, low-gradient aortic stenosis and preserved ejection fraction. Patients exhibiting a HFpEF and atrial fibrillation phenotype faced a significantly higher risk of cardiovascular mortality and heart failure hospitalisation at 1 and 5 years. These findings suggest that targeted guideline-directed medical therapy for HFpEF, including SGLT2 inhibitors and MRAs, may improve outcomes in this high-risk subgroup.
In patients undergoing transcatheter aortic valve implantation (TAVI), a low flow, low-gradient (LF-LG) is often caused by reduced left ventricular ejection fraction (LVEF). However, characteristics and causes of worse outcomes in patients with a paradoxical LF-LG with preserved ejection fraction (pEF) are less well understood.
To phenotype patients with LF-LG pEF, based on unsupervised echocardiographic clustering.
We included 827 patients undergoing TAVI in a tertiary medical centre in the Netherlands. LF-LG pEF was defined as LVEF≥50%, Aortic Valve Area: ≤ 1.0 cm2, mean gradient <40 mmHg, and a stroke volume index <35ml/m2. K-means clustering was performed using principal component analysis on 323 AI-assessed echocardiographic parameters (US2.ai). Validation was performed both internal (n=405) and external (n=173) (TUMunich, Germany).
From 827 patients undergoing TAVI, 216 patients (35%) had a LF-LG pEF status (mean age of 78.8 (± 7.19) years, 57.9% female), in which two clusters were identified. Patients in cluster 1 (n=77) were characterized by distinct echocardiographic features related to HFpEF, including larger left (LA) and right atrial dimensions (as shown by volume, area, length, width and circumference), and impaired left ventricular global longitudinal strain and a reduced LA reservoir strain (in different echocardiographic views). Also, they were older, and had higher rates of atrial fibrillation (AF) and heart failure (HF), and higher HFpEF scores (49.4% H2FPEF score ≥6 and 71.4% HFA-pEFF score ≥5), compared to cluster 2 (n=139). Cluster 1 had a higher risk of 1-and 5-year cardiovascular mortality and HF-hospitalisations, similar to classical LF-LG patients. Internal and external validation revealed similar results.
One-third of TAVI patients with LF-LG aortic stenosis have a typical HFpEF/AF-phenotype and a poor prognosis. They may benefit from guideline-directed medical therapies for patients with HFpEF, including SGLT-2 inhibitors and MRA.
