New Echo Method Predicts Survival After Heart Valve Implantation

For millions of older adults with a narrowed aortic valve, the decision to undergo transcatheter aortic valve implantation, or TAVI, often hinges on a handful of numbers gathered from an echocardiogram. Among those numbers, the ejection fraction has long reigned as the standard measure of how well the left ventricle pumps blood. Yet cardiologists have known for decades that this figure can be misleading, because it depends heavily on the load the heart is working against. A new study published in GeroScience by researchers at Semmelweis University in Budapest suggests that a more sophisticated, volume-aware measure of cardiac work may finally capture what ejection fraction and even strain imaging miss: the true contractile state of an aging, overloaded heart.

The research team, led by Tímea K. Turschl and Béla Merkely, enrolled 300 patients scheduled for TAVI at their institute between April 2020 and December 2023, with a mean age of 78.7 years. Each patient underwent detailed transthoracic echocardiography and blood pressure measurement 24 to 48 hours before the procedure. Over a median follow-up of 25 months, 62 patients died from any cause. The investigators then asked a deceptively simple question: could a novel echocardiographic index, computed from routine images and a blood pressure cuff, predict who would survive and who would not?

To understand the innovation, it helps to trace the evolution of cardiac function assessment. The gold standard for measuring the heart’s intrinsic contractility is the pressure–volume loop, obtained by threading a conductance catheter into the left ventricle during cardiac catheterization. This invasive technique plots ventricular pressure against volume throughout the cardiac cycle, yielding load-independent indices of myocardial performance. Because of its complexity and risk, it is reserved for a handful of selected patients and cannot be used routinely. Echocardiography, by contrast, is cheap, safe and ubiquitous, but its most popular outputs, ejection fraction and global longitudinal strain, are strongly load-dependent, meaning they reflect not only the muscle’s contractile power but also the hemodynamic conditions imposed on it.

Pressure–strain loop-derived myocardial work analysis was introduced to bridge this gap. The method estimates the left ventricular pressure curve non-invasively by scaling a normalized reference pressure curve to the patient’s measured brachial systolic pressure, adding the Doppler-derived transvalvular gradient in aortic stenosis patients. This pressure trace is then integrated with strain curves obtained from speckle-tracking echocardiography, producing pressure–strain loops from which indices such as global work index, global constructive work, global wasted work and global work efficiency are calculated. Constructive work represents myocardial shortening during systole and lengthening during diastole, while wasted work captures the energetically futile deformation that occurs when segments contract against uncoordinated loads. Previous studies have shown these indices correlate well with invasive measures of contractility and outperform conventional parameters in predicting outcomes across cardiovascular diseases.

But the Hungarian team identified a blind spot: standard myocardial work indices ignore ventricular geometry and preload entirely. In aortic stenosis, chronic pressure overload drives concentric remodeling, and many elderly patients also carry volume overload and altered chamber sizes that fundamentally change how strain and pressure translate into actual mechanical output. Building on their earlier translational work in rodent models of heart failure, where pressure–strain–volume loops correlated even more strongly with gold-standard contractility than conventional work metrics, the researchers multiplied the pressure–strain loops by instantaneous left ventricular volume, frame by frame, before integration. The resulting volume-adjusted indices, GWIVi and GCWVi, were normalized to body surface area, yielding values expressed in mmHg%L per square meter.

The first striking result emerged when the cohort was divided into the three classic hemodynamic phenotypes of severe aortic stenosis: normal-flow high-gradient, classical low-flow low-gradient, and paradoxical low-flow low-gradient. Conventional measures told a familiar but incomplete story. Global longitudinal strain and standard work index were significantly reduced only in the classical low-flow low-gradient group, while paradoxical low-flow patients, who typically present with small, stiff, seemingly hypercontractile ventricles, looked comparable to normal-flow patients. The volume-adjusted GWIVi, however, revealed that both low-flow subgroups shared a similarly depressed myocardial work capacity, at 46.98 and 51.99 mmHg%L/m² respectively, compared with 63.74 in the normal-flow high-gradient group, a difference that was highly significant. In other words, the new index unmasked ventricular dysfunction that standard echocardiographic parameters underestimated in the paradoxical phenotype.

The prognostic findings were equally compelling. In univariate analysis, ejection fraction failed to predict mortality at all, while global longitudinal strain, global constructive work, GWIVi and GCWVi were all significantly associated with survival. When the researchers constructed fully adjusted multivariable Cox regression models incorporating clinically relevant factors such as age, male sex, hemoglobin, atrial fibrillation and diabetes mellitus, only the volume-adjusted indices remained significant independent predictors. GWIVi carried a hazard ratio of 0.955 per unit increase, and adding either index significantly improved the fit of the clinical reference model according to likelihood-ratio testing, whereas ejection fraction, strain and standard work indices did not. GCWVi also predicted mortality independently of low-flow low-gradient status, demonstrating that its prognostic power was not simply a proxy for the hemodynamic subtype.

Perhaps most clinically relevant was the performance of the new index in patients with preserved ejection fraction, a notoriously difficult group in whom conventional markers often appear reassuring despite adverse outcomes. Among the 157 patients with an ejection fraction of 50 percent or higher, 32 died during follow-up. In this subgroup, only GCWVi and atrial fibrillation emerged as predictors of mortality, and GCWVi remained an independent predictor even after adjustment for age and sex. Kaplan–Meier analysis showed that patients with GCWVi values above the cohort median had significantly better survival, both in the total population and in the preserved ejection fraction subgroup, with log-rank p-values of 0.017 and 0.007 respectively. A representative case pair illustrated the point vividly: one patient with preserved ejection fraction and strain but low volume-adjusted work died 17 months after TAVI, while another with moderately reduced conventional measures but high GWIVi survived the entire follow-up period.

The implications extend beyond prognostication. TAVI has become the most common valvular procedure worldwide, yet no dedicated perioperative risk stratification system has gained general acceptance, and the widely used EuroSCORE II was designed for open-heart surgery. The authors argue that in hemodynamic overload states such as aortic stenosis, pressure–strain–volume analysis may provide a more physiologically accurate depiction of left ventricular function, precisely because it accounts for the chamber’s size and filling state rather than deformation alone. Encouragingly, the technique requires only minimal additional post-processing on top of routine echocardiography, using images and blood pressure data already collected before the procedure.

Important caveats remain. The study was single-center, all procedures used one ultrasound vendor, and the technique depends on adequate image quality for speckle-tracking and endocardial border contouring, which may have introduced selection bias toward patients with better echocardiographic windows. The authors themselves call for multicenter validation and methodological standardization before broader clinical implementation, and note that atrial and right ventricular strain, which are relevant prognostic markers in TAVI candidates, were not assessed. Still, the message is clear: by folding ventricular volume into the calculation of myocardial work, cardiologists may gain a window into the aging heart’s true contractile reserve, one that ejection fraction has never provided. For the growing population of elderly patients facing valve replacement, that window could mean better-informed decisions about when, and whether, to intervene.

Subject of Research: Non-invasive pressure-strain-volume loop analysis for predicting survival after transcatheter aortic valve implantation in aortic stenosis

Article Title: Integrating volumes into myocardial work: the prognostic role of non-invasive pressure-strain-volume analysis in transcatheter aortic valve implantation

Article References: Turschl, T. K., Ladányi, Z., Ferencz, A., Fábián, A., Tokodi, M., Szijártó, Á., Ruppert, M., Nagy, A., Molnár, A. Á., Molnár, L., Zima, E., Kovács, A., Lakatos, B. K., & Merkely, B. (2026). Integrating volumes into myocardial work: the prognostic role of non-invasive pressure-strain-volume analysis in transcatheter aortic valve implantation. GeroScience. https://doi.org/10.1007/s11357-026-02583-3

Image Credits: AI Generated

DOI: 10.1007/s11357-026-02583-3

Keywords: aortic stenosis, TAVI, echocardiography, myocardial work, pressure-strain-volume loops, left ventricular function, ejection fraction, global longitudinal strain, prognosis, valvular heart disease, cardiac contractility, GeroScience