TAVI Success Is More Than Just the Valve: CT-Derived Sarcopenia as a Major Determinant of Long-Term Survival

Abstract

Background: Sarcopenia, characterized by progressive skeletal muscle loss, is a silent yet powerful marker associated with survival, yet its impact on long-term outcomes in transcatheter aortic valve implantation (TAVI) remains underestimated. While frailty has been recognized as a main factor of resilience and recovery, the role of muscle integrity is frequently overlooked. This study explores whether computed tomography (CT)-derived psoas muscle area (PMA) and psoas muscle area index (PMI) are key predictors of post-TAVI survival.

Methods: A total of 539 patients (mean age 82.0 ± 5.1 years; 49.9% female) undergoing TAVI were analysed in this retrospective, single-centre study. Sarcopenia was analysed via sex-specific quartiles of PMA and PMI. Long-term survival was examined using Kaplan-Meier analysis, univariate and multivariate Cox regression analysis. Interaction terms were introduced to assess whether the association between sarcopenia and survival differed by age, sex, renal function and anaemia status.

Results: Sarcopenia emerged as a predictor of long-term mortality (HR = 1.52, p = 0.011 for PMA; HR = 1.55, p = 0.008 for PMI) after TAVI. Notably, younger patients (< 80 years) with sarcopenia faced double the mortality risk (HR = 2.48, p = 0.001 for PMA; HR = 2.55, p = 0.001 for PMI), whereas in older patients, the association was weaker. In women, who typically show a post-TAVI survival advantage, sarcopenia reduced this benefit (HR = 1.75, p = 0.020 for PMA; HR = 1.88, p = 0.008 for PMI). The most striking finding was the synergistic effect of sarcopenia and chronic kidney disease (CKD), resulting in a threefold increase in mortality risk (HR = 2.82, p = 0.027 for PMA; HR 3.14, p = 0.011). After multivariate adjustment, sarcopenia remained a strong, independent predictor of long-term mortality (HR = 1.58, p = 0.009 for PMA; HR = 1.49, p = 0.024 for PMI), reinforcing its clinical relevance in TAVI risk stratification.

Conclusion: Our study suggests that sarcopenia is not just a passive bystander, but may serve as a marker associated with long-term mortality in TAVI patients, especially in younger individuals, women and those with CKD or anaemia. Since muscle mass predicts survival and is potentially modifiable, assessing and intervening against sarcopenia before and after TAVI could represent a clinical priority in patients with aortic valve stenosis. This study underscores the importance of a more nuanced approach-not merely focusing on valve replacement, but on strengthening patient-centred care.

Keywords: TAVI; computed tomography; psoas muscle area; psoas muscle area index; sarcopenia.

FIGURE 1

Radiological measurement of PMA. Figure 1 demonstrates the assessment of bilateral psoas muscle cross‐sectional areas through manual delineation of their contours on an axial CT scan. The combined area of both muscles, normalized to BSA, was utilized to derive the PMI. Abbreviations: BSA, body surface area; CT, computed tomography; PMA, psoas muscle area; PMI, psoas muscle area index; Q, quartile.

FIGURE 2

Sex‐specific quartile distribution of PMA and PMI, used for sarcopenia classification in the study cohort. Abbreviations: PMA, psoas muscle area; PMI, psoas muscle area index; Q, quartile.

FIGURE 3

Kaplan–Meier survival curves for PMA and PMI with numbers at risk and corresponding log‐rank tests, comparing long‐term survival in sarcopenic and nonsarcopenic patients. Abbreviations: no., number; PMA, psoas muscle area; PMI, psoas muscle area index; Q, quartile; TAVI, transcatheter aortic valve implantation.

FIGURE 4

Univariate Cox regression analysis of sarcopenia (PMA and PMI), showing hazard ratios and 95% confidence intervals for different patient subgroups. Abbreviations: BMI, body mass index; CI, confidence interval; LVEF, left ventricular ejection fraction; no., number; NYHA, New York Heart Association Functional Classification; PMA, psoas muscle area; PMI, psoas muscle area index; SVi, stroke volume index.

FIGURE 5

Heat maps illustrating interaction terms between sarcopenia (PMA and PMI), renal function, anaemia, age and sex, highlighting their combined impact on long‐term survival. Abbreviations: BMI, body mass index; LVEF, left ventricular ejection fraction; NYHA, New York Heart Association Functional Classification; PMA, psoas muscle area; PMI, psoas muscle area index; SVi, stroke volume index.

FIGURE 6

Graphical abstract. Abbreviations: BSA, body surface area; CI, confidence interval; HR, hazard ratio; PMA, psoas muscle area; PMI, psoas muscle area index; TAVI, transcatheter aortic valve implantation.