Diagnostic utility of right ventricular free wall strain for cardiac amyloidosis in patients undergoing transcatheter aortic valve implantation
t yoshii, K matsushita, K Terasaka, K Hattori, S Kikuchi, Y Hanajima, H Kirigaya, H Nakahashi, M Gohbara, Y Kimura, K Okada, M Kosuge, T Ebina, N Iwahashi, K HibiAbstract
Background
Although relative apical sparing (RAS) and apical sparing pattern of left ventricular (LV) longitudinal strain is a commonly used echocardiographic marker for diagnosing cardiac amyloidosis (CA), its diagnostic performance is limited in patients with aortic stenosis. In contrast, CA is also characterized by right ventricular dysfunction, including impaired right ventricular free wall strain (RVFWS).
Purpose
We investigated whether RVFWS provides superior diagnostic value for CA compared with RAS and other echocardiographic parameters in patients undergoing transcatheter aortic valve implantation (TAVI).
Methods
This single-center retrospective study included 274 consecutive patients who underwent TAVI between 2022 and 2025. After excluding 7 patients who underwent valve in valve, 43 patients who did not undergo endomyocardial biopsy (due to unstable hemodynamics, intracardiac device implantation, left bundle branch block, or physician’s decision) and 7 with inadequate echocardiographic images, 217 patients were included in the final analysis. All patients underwent echocardiography and endomyocardial biopsy before TAVI. RVFWS (Figure 1), LV RAS, and the Increased Wall Thickness (IWT) score, which has been reported to be useful for the diagnosis of CA in patients with increased LV wall thickness, were compared using receiver operating characteristic (ROC) curve analysis for the diagnosis of CA.
Results
The mean age was 84 ± 5 years, and CA was diagnosed in 19 patients (8.8%). Compared with non-CA patients, those with CA had higher LV RAS (0.89 ± 0.22 vs 0.77 ± 0.23, p = 0.027) and significantly lower tricuspid annular plane systolic excursion (17.5 ± 3.2 mm vs 19.9 ± 4.0 mm, p = 0.010), right ventricular fractional area change (37.7 ± 6.3% vs 44.0 ± 4.7%, p < 0.001), and RVFWS (17.3 ± 3.7% vs. 21.6 ± 3.0%, p < 0.001). On ROC analysis, RVFWS demonstrated a significantly higher area under the curve (AUC) for the diagnosis of CA compared with LV RAS and the IWT score (AUC 0.81 [95% CI 0.68–0.90] vs. 0.66 [0.52–0.78], p = 0.038; and AUC 0.81 [0.68–0.90] vs. 0.61 [0.49–0.72], p = 0.011, respectively) (Figure 2).
Conclusions
In patients undergoing TAVI, RVFWS may provide superior diagnostic accuracy for CA compared with LV RAS and the IWT score.Figure 1Figure 2