Background Pulmonary hypertension is characterized by extensive remodelling of the pulmonary tree, with enlargement of the pulmonary arteries. The predictive value of pulmonary hypertension in patients undergoing transcatheter aortic valve replacement (TAVR) has been demonstrated. We aimed to evaluate the prognostic impact of the pre-procedural main pulmonary artery (mPA) enlargement, assessed by computed tomography angiography, in patients undergoing TAVR for severe aortic stenosis (AS). Methods We retrospectively analyzed 337 consecutive patients with AS from our local registry who underwent right heart catheterization and computed tomography angiography before TAVR. The cohort was divided into 2 groups according to the presence of an enlarged mPA (mPA axial diameter ≥ 29 mm for male patients and ≥ 27 mm for female patients, mPAe, n = 192, mean age 83 ± 6 years, 41% male) or not (mPAn, n = 145, mean age 84 ± 6 years, 46% male). The primary endpoint was all-cause mortality at 1 year. Results A significant correlation between invasive mean pulmonary artery pressure and mPA axial diameter was noted (Pearson r = 0.393, P < 0.001). Compared with the mPAn group, patients with an enlarged mPA had higher 1-year mortality rates (hazard ratio [HR]: 2.59, 95% confidence interval [CI]: 1.11-6.04, P = 0.027). The prognostic significance was even stronger after indexing the mPA diameter to the ascending aortic diameter (HR 3.83, 95% CI: 1.85-7.87, P < 0.001). This measure remained significant after adjustment for baseline comorbidities (adjusted HR 4.2; 95% CI: 2.00-8.98, P < 0.001). Conclusions Pre-procedural mPA enlargement is strongly associated with 1-year all-cause mortality in patients undergoing TAVR. This finding may pave the way for a more precise noninvasive risk stratification in patients with severe AS.

BACKGROUND:Carotid-to-femoral pulse wave velocity (c-f PWV) is commonly used to assess large artery stiffness, particularly as a surrogate of aortic stiffness. Given that c-f PWV represents the average stiffness of all main arteries along the carotid-to-femoral arterial pathway, without specifically accounting for the stiffness of the proximal aorta, we hypothesized that c-f PWV may not represent stricto sensu the stiffness of the ascending aorta (AAO), which is the main contributor to total arterial compliance ( CT ). METHODS:To test our hypothesis, we recruited 45 healthy volunteers from different age groups. We evaluated the relation between c-f PWV and different indices of proximal aorta stiffness calculated from distensibility (AAO dist PWV) and characteristic impedance (Zc) in frequency (AAO Z c(f) PWV) and time domain (AAO Zc(t) PWV) and compared their relationships with age and CT . 2D phase contrast MRI was performed to measure AAO flow and cross-sectional area. Tonometry was used to obtain c-f PWV and pressure waveforms. RESULTS:In healthy individuals, AAO PWV indices demonstrated a strong relationship with each other ( R  ≥ 0.86), but c-f PWV did not show high correlations with AAO PWV indices ( R  ≤ 0.50). All AAO PWV indices increased with age ( P  ≤ 0.05); however, c-f PWV did not increase from young to middle-aged ( P  = 0.13) and middle-aged to old age groups ( P  = 0.28). AAO PWV indices correlated well with C T ( R2  ≥ 0.60), whereas c-f PWV did not ( R2  = 0.23). CONCLUSION:The present study reveals that a complete understanding of large artery stiffness requires the direct assessment of proximal aortic stiffness rather than surrogate indices such as c-f PWV.

The year 2024 has seen significant progress in the management of heart failure. New treatments have demonstrated their efficacy, particularly for heart failure with preserved ejection fraction, cardiac amyloidosis, and hypertrophic cardiomyopathy. Advances in imaging, such as MRI and PET-CT, highlight the growing integration of innovative technologies and artificial intelligence in cardiology for diagnosing complex cardiovascular diseases. In the field of adult congenital heart disease, SGLT2 inhibitors show promising results in heart failure treatment, and percutaneous techniques have yielded positive outcomes. In cardio-oncology, new studies have focused on the prevention and management of cancer therapy-related cardiac dysfunction.

We report the case of a female patient in her 60s with advanced ovarian cancer and Trousseau's syndrome, who presented with a stroke. An unusual biphasic femoral flow led to transthoracic echocardiography that revealed a severe aortic regurgitation (AR) secondary to a prolapsed right coronary aortic valve leaflet. An initial echocardiography missed the diagnosis due to tachycardia. Transcatheter aortic valve replacement (TAVR) resulted in symptom improvement. She was readmitted 2 years later with prosthetic valve thrombosis, ultimately succumbing to oncological complications. This case highlights challenges in diagnosing AR and the potential role of TAVR in patients with native pure AR (NPAR). While TAVR for NPAR poses technical challenges, newer generation transcatheter heart valves (THVs) offer promising outcomes. The Acurate NEO 2 valve was successfully used in this case. TAVR with off-label THVs can be considered for selected NPAR patients, and we can expect increased utilisation of on-label devices when availability issues are solved.

The year 2024 has seen significant progress in the management of heart failure. New treatments have demonstrated their efficacy, particularly for heart failure with preserved ejection fraction, cardiac amyloidosis, and hypertrophic cardiomyopathy. Advances in imaging, such as MRI and PET-CT, highlight the growing integration of innovative technologies and artificial intelligence in cardiology for diagnosing complex cardiovascular diseases. In the field of adult congenital heart disease, SGLT2 inhibitors show promising results in heart failure treatment, and percutaneous techniques have yielded positive outcomes. In cardio-oncology, new studies have focused on the prevention and management of cancer therapy-related cardiac dysfunction.

Stroke volume (SV) is a major indicator of cardiovascular function, providing essential information about heart performance and blood flow adequacy. Accurate SV measurement is particularly important for assessing patients with heart failure, managing patients undergoing major surgeries, and delivering optimal care in critical settings. Traditional methods for estimating SV, such as thermodilution, are invasive and unsuitable for routine diagnostics. Non-invasive techniques, although safer and more accessible, often lack the precision and user-friendliness needed for continuous bedside monitoring. We developed a modified method for SV estimation that combines a validated 1-D model of the systemic circulation with machine learning. Our approach replaces the traditional optimization process developed in our previous work, with a regression method, utilizing an in silico-generated dataset of various hemodynamic profiles to create a gradient boosting regression-enabled SV estimator. This dataset accurately mimics the dynamic characteristics of the 1-D model, allowing for precise SV predictions without resource-intensive parameter adjustments. We evaluated our method against SV values derived from the gold standard thermodilution method in 24 patients. The results demonstrated that our approach provides a satisfactory agreement between the predicted and reference data, with a MAE of 16 mL, a normalized RMSE of 21%, a bias of −9.2 mL, and limits of agreement (LoA) of [−47, 28] mL. A correlation coefficient of r = 0.7 (p < 0.05) was reported, with the predicted SV slightly underestimated (68 ± 23 mL) in comparison to the reference SV (77 ± 26 mL). The significant reduction in computational time of our method for SV assessment should make it suitable for real-time clinical applications.

A 60-year-old woman was scheduled for elective coronary angiography after a positron emission tomography and computer tomography (PET-CT) cardiac perfusion imaging test showing extensive myocardial ischemia. A few hours before the scheduled angiography, she presented to the emergency room with chest pain and diffuse ST-segment modifications leading to emergent coronary angiography. Recent PET-CT ischemia and viability maps were available at the time of the intervention, favoring a percutaneous coronary intervention for chronic total occlusion (CTO PCI) of the left circumflex artery, apart from the culprit lesion of the left main coronary artery and left anterior descending artery, with good results. A second PET-CT scan 23 days post-PCI showed a reversible perfusion defect of the first diagonal branch territory, which was subsequently treated. A rapid normalization of the left ventricular ejection fraction (LVEF) was noted after revascularization, while the second PET-CT showed no signs of significant myocardial necrosis. This case illustrates the potential role of cardiac imaging perfusion studies in guiding revascularization in complex cases in the context of an acute myocardial infarction (MI).

Left atrial wall fibrosis has an important role in atrial fibrillation (AF) because of the abnormal electrophysiological properties of the fibrotic areas. However, the mechanisms behind the development of left atrial fibrosis are not well understood. Here, we examine the association between regional wall shear stress and areas with fibrosis in the left atrium of patients with AF. We recruited 15 patients with AF for an observational prospective study involving baseline three-dimensional (3D) electroanatomical mapping of the left atrium and preinterventional cardiovascular magnetic resonance imaging to detect left atrial fibrosis. We extracted a 3D anatomical model of the left atrium from the electroanatomical maps. Then, we calculated regional time-averaged wall shear stress (TAWSS) and blood stagnation by performing patient-specific computational fluid dynamic simulations. We found that fibrosis and electrical scarring were more prevalent in areas exposed to high TAWSS without blood stagnation, whereas areas with low TAWSS were associated with blood stagnation.

Background: Pulmonary hypertension is associated with extensive remodeling of the pulmonary tree, with key finding the enlargement of the pulmonary artery (PA). Although the independent predictive value of the pulmonary hypertension in patients undergoing transcatheter aortic valve replacement for severe aortic stenosis has been clearly demonstrated, data about the potential predictive value of the pre-interventional PA enlargement on mortality are scarce. Research questions: The aim of the present study was to assess the prognostic significance of the pre-interventional PA enlargement, assessed by cardiac CT scan, in patients undergoing transcatheter aortic valve replacement for severe aortic stenosis. Methods: We conducted a retrospective study and recruited 337 patients with aortic stenosis, who underwent a right heart catheterization and a cardiac CT scan before the transcatheter aortic valve replacement. The cohort was divided in two groups according to the presence of an enlarged PA (PA e ), (main PA axial diameter ≥ 29 mm for males and ≥ 27 mm for females, n=192, mean age 83±6 years, 41% males) or not (PA n ), ( n=145, mean age 84±6 years, 46% males). The primary endpoint was all-cause mortality at 1 year. Results: Globally, a strong correlation between invasive mean PA pressure and main PA axial diameter was noted (Pearson r=0.393, p<0 .001). Compared to the PA n group, patients with enlarged PA exhibited higher 1 year mortality rates (hazard ratio 2.51, 95% CI: 1.1-6.04, p=0.027). The prognostic significance was even stronger after indexing the PA to the ascending aorta diameter (hazard ratio 3.82, 95% CI: 1.86-7.87, p<0.001, figure 1). Conclusions: Pre interventional PA enlargement, is strongly associated with 1-year all-cause mortality in patients undergoing transcatheter aortic valve. This may pave the way for a more precise non-invasive risk stratification in patients with severe aortic stenosis.

Left atrial (LA) wall fibrosis plays an important role in the perpetuation of atrial fibrillation (AF) since the abnormal electrophysiological properties of the fibrotic areas sustains the arrhythmia by favoring both re-entry circuits as well as abnormal impulse generation. Despite its crucial contribution, the mechanisms by which LA fibrosis develops are not well understood. The LA wall is constantly exposed to the hydraulic forces exerted by the blood flow arriving from the pulmonary veins. The purpose of the present study was to examine the association between regional wall shear stress and areas with fibrosis in the LA of patients with AF. 15 patients (13 males, mean age 61±11 years) with AF, no significant mitral regurgitation and clinical indication for a primary catheter ablation were prospectively recruited for the study. All participants underwent a baseline three-dimensional electro-anatomical mapping of the LA during the ablation procedure and a pre-interventional cardiovascular magnetic resonance (CMR) imaging with phase contrast for mitral flow estimation and Gadolinium injection for LA fibrosis detection. Fibrotic areas were detected either by low bipolar voltage (BV≤0.5mV) and/or by areas with enhanced late Gadolinium uptake as assessed by the image intensity ratio (IIR≥1.2). For all subjects, a detailed 3D anatomical model of the LA was extracted from the invasive electro-anatomical maps and was used to calculate regional time-averaged wall shear stress (TAWSS) and blood age (BA), an index of blood stagnation, by performing patient-specific computational fluid dynamic simulations. Globally, areas around the pulmonary veins and the LA roof exhibited the highest values of TAWSS. In all cases, high TAWSS was strongly correlated with low voltage (n=15, r from -0.002 to -0.449, p<0.01) and enhanced late Gadolinium uptake (n=12, r from 0.071 to 0.475, p<0.001). Fibrotic areas as detected by both low BV and high IIR were more prevalent in areas exposed to high TAWSS (21.6% vs 8.1% and 26.2% vs 13.2% respectively, p<0.001). Inversely, in all but one case, areas with low TAWSS presented more intense blood stagnation as assessed by the highest BA (r from -0.268 to -0.688, p<0.001). In patients with AF, regional high TAWSS is associated with corresponding CMR biomarkers of left atrial wall fibrosis and electrical scaring. Inversely, areas with low TAWSS are associated with blood stagnation and could favor thrombus formation. This may provide insights of a novel pathophysiological mechanism explaining the characteristic atrial electrical remodeling and thrombus formation seen in patients with AF. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement The project has been financially supported by Geneva University Hospitals (HUG D. Adamopoulos, Projet recherche et developpement). ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: The Commission Cantonale d'Éthique de la Recherche sur l'être humain of the Canton of Geneva gave ethical approval for this work, approval number: 2023-02314. I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data used in this study are available in the Manuscript and the Supplementary Material. The software is available at https://github.com/g-rov/lausm.

BACKGROUND:Achieving optimal exposure of the mitral valve during surgical intervention poses a significant challenge. This study aimed to compare perioperative and postoperative outcomes associated with 3 left atriotomy techniques in mitral valve surgery-the conventional direct, transseptal, and superior septal approaches-and assess differences during the surgical procedure and the postoperative period.METHODS:Inclusion criteria were patients undergoing mitral valve surgery from January 2010 to December 2020, categorized into 3 cohorts: group 1 (conventional direct; n = 115), group 2 (transseptal; n = 33), and group 3 (superior septal; n = 59). To bolster sample size, the study included patients undergoing mitral valve surgery independently or in conjunction with other procedures (eg, coronary artery bypass grafting, aortictricuspid surgery, or maze procedure).RESULTS:No substantial variance was observed in the etiology of mitral valve disease across groups, except for a higher incidence of endocarditis in group 3 (P = .01). Group 1 exhibited a higher frequency of elective surgeries and isolated mitral valve procedures (P = .008), along with reduced aortic clamping and cardiopulmonary bypass durations (P = .002). Conversely, group 3 patients represented a greater proportion of emergency procedures (P = .01) and prolonged intensive care unit and hospital stays (P = .001). No significant disparities were detected in terms of permanent pacemaker implantation, postoperative complications, or mortality among the groups.CONCLUSION:Mitral valve operations that employed these 3 atriotomy techniques demonstrated a safe profile. The conventional direct approach notably reduced aortic clamping and cardiopulmonary bypass durations. The superior septal method was primarily employed for acute pathologies, with no significant escalation in postoperative arrhythmias or permanent pacemaker implantation, although these patients had prolonged intensive care unit and hospital stays. These outcomes may be linked to the underlying pathology and nature of the surgical intervention rather than the incision method itself.

The transaortic valvular pressure gradient (TPG) plays a central role in decision-making for patients suffering from severe aortic stenosis. However, the flow-dependence nature of the TPG makes the diagnosis of aortic stenosis challenging since the markers of cardiac performance and afterload present high physiological interdependence and thus, isolated effects cannot be measured directly in vivo. We used a validated 1D mathematical model of the cardiovascular system, coupled with a model of aortic stenosis, to assess and quantify the independent effect of the main left ventricular performance parameters (end-systolic (Ees) and end-diastolic (Eed) elastance) and principal afterload indices (total vascular resistance (TVR) and total arterial compliance (TAC)) on the TPG for different levels of aortic stenosis. In patients with critical aortic stenosis (aortic valve area (AVA) ≤ 0.6 cm2), a 10% increase of Eed from the baseline value was associated with the most important effect on the TPG (−5.6 ± 0.5 mmHg, p < 0.001), followed by a similar increase of Ees (3.4 ± 0.1 mmHg, p < 0.001), in TAC (1.3 ±0.2 mmHg, p < 0.001) and TVR (−0.7 ± 0.04 mmHg, p < 0.001). The interdependence of the TPG left ventricular performance and afterload indices become stronger with increased aortic stenosis severity. Disregarding their effects may lead to an underestimation of stenosis severity and a potential delay in therapeutic intervention. Therefore, a comprehensive evaluation of left ventricular function and afterload should be performed, especially in cases of diagnostic challenge, since it may offer the pathophysiological mechanism that explains the mismatch between aortic severity and the TPG.

In the last few years, technological advances in MR imaging, PET detectors, and attenuation correction algorithms have allowed the creation of truly integrated PET/MR imaging systems, for both clinical and research applications. These machines allow a comprehensive investigation of cardiovascular diseases, by offering a wide variety of detailed anatomical and functional data in combination. Despite significant pathophysiologic mechanisms being clarified by this new data, its clinical relevance and prognostic significance have not been demonstrated yet.

IntroductionArterial wave reflection is an important component of the left ventricular afterload, affecting both pressure and flow to the aorta. The aim of the present study was to evaluate the impact of wave reflection on transvalvular pressure gradients (TPG), a key parameter for the evaluation of aortic valve stenosis (AS), as well as its prognostic significance in patients with AS undergoing a transcatheter aortic valve replacement (TAVR).Materials and MethodsThe study population consisted of 351 patients with AS (mean age 84 ± 6 years, 43% males) who underwent a complete hemodynamic evaluation before the TAVR. The baseline assessment included right and left heart catheterization, transthoracic echocardiography, and a thorough evaluation of the left ventricular afterload by means of wave separation analysis. The cohort was divided into quartiles according to the transit time of the backward pressure wave (BWTT). Primary endpoint was all-cause mortality at 1 year.ResultsEarly arrival of the backward pressure wave was related to lower cardiac output (Q1: 3.7 ± 0.9 lt/min vs Q4: 4.4 ± 1.0 lt/min, p < 0.001) and higher aortic systolic blood pressure (Q1: 132 ± 26 mmHg vs Q4: 117 ± 26 mmHg, p < 0.001). TPG was significantly related to the BWTT, patients in the arrival group exhibiting the lowest TPG (mean TPG, Q1: 37.6 ± 12.7 mmHg vs Q4: 44.8 ± 14.7 mmHg, p = 0.005) for the same aortic valve area (AVA) (Q1: 0.58 ± 0.35 cm2 vs 0.61 ± 0.22 cm2, p = 0.303). In multivariate analysis, BWTT remained an independent determinant of mean TPG (beta 0.3, p = 0.002). Moreover, the prevalence of low-flow, low-gradient AS with preserved ejection fraction was higher in patients with early arterial reflection arrival (Q1: 33.3% vs Q4: 14.9%, p = 0.033). Finally, patients with early arrival of the reflected wave (Q1) exhibited higher all-cause mortality at 1 year after the TAVR (unadjusted HR: 2.33, 95% CI: 1.17–4.65, p = 0.016).ConclusionEarly reflected wave arrival to the aortic root is associated with poor prognosis and significant aortic hemodynamic alterations in patients undergoing a TAVR for AS. This is related to a significant decrease in TPG for a given AVA, leading to a possible underestimation of the AS severity.

Introduction: Pulmonary hypertension (PH), traditionally defined as a mean pulmonary artery pressure (PAP) ≥ 25 mmHg, is associated with poor outcomes in patients undergoing a transcatheter aortic valve replacement (TAVR) for severe aortic stenosis (AS). Recently, a novel definition for PH has been proposed, placing the cut-off value of mean PAP at 20 mmHg, and introducing pulmonary vascular resistance as an exclusive indicator for the pre-capillary involvement. In light of the novel criteria, whether PH still preserves its prognostic significance remains unknown. Methods: The study population consisted of 380 patients with AS, who underwent a right heart catheterization before TAVR. The cohort was divided according to the presence of PH (n = 174, 45.7%) or not. Patients with PH were further divided into the following groups: (1) Pre-capillary PH ((Pre-capPH), n = 46, 12.1%); (2) Isolated post-capillary PH ((IpcPH), n = 78, 20.5%); (3) Combined pre and post-capillary PH ((CpcPH), n = 82, 21.6%). The primary endpoint was all-cause mortality at 1 year. Results: A total of 246 patients (64.7%) exhibited mean PAP > 20 mmHg. Overall, the presence of PH was associated with higher 1-year mortality rates (hazard ratio (HR) 2.8, 95% CI: 1.4–5.8, p = 0.004). Compared to patients with no PH, Pre-capPH and CpcPH (but not IpcPH) were related to higher 1-year mortality (HR 2.7, 95% CI: 1.0–7.2, p = 0.041 and HR 3.9, 95% CI: 1.8–8.5, p = 0.001, respectively). This remained significant even after the adjustment for baseline comorbidities. Conclusions: Pre-interventional PH according to the novel hemodynamic criteria, is linked with poor outcomes in patients undergoing TAVR for severe AS. However, this is mainly driven by patients with mean PAP ≥ 25 mmHg. Patients with a pre-capillary PH component as defined by increased PVR present an even worse prognosis as compared to patients with isolated post-capillary or no PH who present comparable 1-year mortality rates.

Aortic compliance is an important determinant of cardiac afterload and a contributor to cardiovascular morbidity. In the present study, we sought to provide in silico insights into the acute as well as long-term effects of aortic compliance decrease on central hemodynamics. To that aim, we used a mathematical model of the cardiovascular system to simulate the hemodynamics (a) of a healthy young adult (baseline), (b) acutely after banding of the proximal aorta, (c) after the heart remodeled itself to match the increased afterload. The simulated pressure and flow waves were used for subsequent wave separation analysis. Aortic banding induced hypertension (SBP 106 mmHg at baseline versus 152 mmHg after banding), which was sustained after left ventricular (LV) remodeling. The main mechanism that drove hypertension was the enhancement of the forward wave, which became even more significant after LV remodeling (forward amplitude 30 mmHg at baseline versus 60 mmHg acutely after banding versus 64 mmHg after remodeling). Accordingly, the forward wave’s contribution to the total pulse pressure increased throughout this process, while the reflection coefficient acutely decreased and then remained roughly constant. Finally, LV remodeling was accompanied by a decrease in augmentation index (AIx 13% acutely after banding versus −3% after remodeling) and a change of the central pressure wave phenotype from the characteristic Type A (“old”) to Type C (“young”) phenotype. These findings provide valuable insights into the mechanisms of hypertension and provoke us to reconsider our understanding of AIx as a solely arterial parameter.

Left ventricular end-systolic elastance (E es ) is a major determinant of cardiac systolic function and ventricular-arterial interaction. Previous methods for the E es estimation require the use of the echocardiographic ejection fraction (EF). However, given that EF expresses the stroke volume as a fraction of end-diastolic volume (EDV), accurate interpretation of EF is attainable only with the additional measurement of EDV. Hence, there is still need for a simple, reliable, noninvasive method to estimate E es . This study proposes a novel artificial intelligence—based approach to estimate E es using the information embedded in clinically relevant systolic time intervals, namely the pre-ejection period (PEP) and ejection time (ET). We developed a training/testing scheme using virtual subjects ( n = 4,645) from a previously validated in-silico model. Extreme Gradient Boosting regressor was employed to model E es using as inputs arm cuff pressure, PEP, and ET. Results showed that E es can be predicted with high accuracy achieving a normalized RMSE equal to 9.15% (r = 0.92) for a wide range of E es values from 1.2 to 4.5 mmHg/ml. The proposed model was found to be less sensitive to measurement errors (±10–30% of the actual value) in blood pressure, presenting low test errors for the different levels of noise (RMSE did not exceed 0.32 mmHg/ml). In contrast, a high sensitivity was reported for measurements errors in the systolic timing features. It was demonstrated that E es can be reliably estimated from the traditional arm-pressure and echocardiographic PEP and ET. This approach constitutes a step towards the development of an easy and clinically applicable method for assessing left ventricular systolic function.

Accurate assessment of the left ventricular (LV) systolic function is indispensable in the clinic. However, estimation of a precise index of cardiac contractility, i.e., the end-systolic elastance (Ees), is invasive and cannot be established as clinical routine. The aim of this work was to present and validate a methodology that allows for the estimation of Ees from simple and readily available non-invasive measurements. The method is based on a validated model of the cardiovascular system and non-invasive data from arm-cuff pressure and routine echocardiography to render the model patient-specific. Briefly, the algorithm first uses the measured aortic flow as model input and optimizes the properties of the arterial system model in order to achieve correct prediction of the patient's peripheral pressure. In a second step, the personalized arterial system is coupled with the cardiac model (time-varying elastance model) and the LV systolic properties, including Ees, are tuned to predict accurately the aortic flow waveform. The algorithm was validated against invasive measurements of Ees (multiple pressure-volume loop analysis) taken from n=10 heart failure patients with preserved ejection fraction and n=9 patients without heart failure. Invasive measurements of Ees (median 2.4 mmHg/mL, range [1.0, 5.0] mmHg/mL) agreed well with method predictions (nRMSE=9%, ρ=0.89, bias=-0.1 mmHg/mL and limits of agreement [-0.9, 0.6] mmHg/mL). This is a promising first step towards the development of a valuable tool that can be used by clinicians to assess systolic performance of the LV in the critically ill.