About

James Francis Antaki is a professor at Cornell University, affiliated with the Meinig School of Biomedical Engineering. His professional career has been devoted to the development of blood-wetted medical devices, with a focus on their design and clinical application. His research has been pioneering in the physiological feedback control of implanted ventricular assist devices and in creating decision support programs for identifying heart failure patients who could recover with acute mechanical circulatory assistance. Over the past 24 years, he has contributed to the development of several clinically used heart-assist devices, including the Heartmate-II, Novacor, Ventracor, TandemHeart, and Levacor. In 1997, he led a multidisciplinary team that produced the Streamliner heart-assist device, recognized as the world's first magnetically levitated rotodynamic blood pump tested in vivo. His current research emphasizes circulatory support systems for children, decision-support tools for severe heart failure, diagnostic technology for home and point-of-care settings, multi-scale modeling of thrombosis in artificial circulation, and the development of medical devices for global health. A broader project aims to accelerate medical innovation through professional networking among physicians, medical product designers, and patients, all sharing a common goal of improving healthcare through biomedical engineering.

Research topics

• Medicine
• Cardiology
• Materials science
• Biomedical engineering
• Computer science

Selected publications

• Geometry–Encoded Microtrenches Stabilize Endothelium on High Shear Biomaterial Surfaces

  bioRxiv (Cold Spring Harbor Laboratory) · 2026-03-19

  articleOpen access

  Abstract Maintaining a confluent, antithrombotic endothelium on cardiovascular biomaterial surfaces remains a major barrier to long-term hemocompatibility, as endothelial cells (ECs) rapidly denude under supraphysiological shear in prosthetic devices. Here, we hypothesized that mesoscale surface geometry (∼100–200 µm) could reorganize near-wall hemodynamics, preserving endothelial coverage and function under extreme shear. Engineered microtrenches were introduced onto an implant biomaterial to generate spatially defined shear environments. Under supraphysiological near-wall shear (∼250 dyn/cm²), microtrenched geometries created attenuated shear and vorticity gradients. Endothelial monolayers were sustained in these flow domains for 120 hours, whereas flat controls rapidly denuded. Endothelial retention in 22.5° angled trenches increased dramatically, from an EC₅₀ of 33 to 101 dyn/cm². 45° angled trenches further increased endothelial shear resistance to an EC₅₀ of 207 dyn/cm². Endothelial monolayers demonstrated collective mechano-adaptation to ultra-high shear through VE-cadherin junction thickening and coordinated cytoskeletal and nuclear alignment. Mechanoadapted monolayers exhibited increased eNOS expression correlated with local shear and elevated nitrite production (45°: 50.4 ± 6.1 µM; 22.5°: 35.7 ± 3.3 µM; 0°: 28.4 ± 6.8 µM). In contrast, interfaces with abrupt shear transitions or elevated rotational flow exhibited reduced coverage, junctional thinning, and re-emergence of VCAM-1 and PAI-1, indicating inflammatory and pro-thrombotic activation. Structural, functional, and inflammatory readouts exhibited peak responses within a shared shear–vorticity regime. Multivariate regression identified shear–vorticity coupling as the dominant predictor of endothelial persistence, with optima clustering within a mechanical range (≈0.8–2.9 × 10⁶ dyn·cm⁻²·s⁻¹). These findings establish geometry-driven modulation of near-wall flow as a predictive, material-agnostic strategy for endothelialization and vasoprotection of high-shear cardiovascular implants.

  PublisherOA PDFDOI

• <span>A Comprehensive Numerical Model of Thrombus Embolization: Fluid-Thrombus Interactions Through a Coupled Computational Fluid Dynamics - Peridynamics Framework</span><br>

  SSRN Electronic Journal · 2026-01-01

  preprintOpen accessSenior author
  PublisherDOI

• Computational Fluid Dynamics Simulation of Endothelium-Modulated Thrombosis

  Journal of Cardiovascular Translational Research · 2026-02-18

  articleSenior author
  PublisherDOI

• Red blood cell entrapment in thrombi formed under pathological flow: Stiffness and binding antigens impact thrombus morphology and cell distribution

  Acta Biomaterialia · 2025-05-23 · 2 citations

  article
  PublisherDOI

• Multi-scale simulation of red blood cell trauma in large-scale high-shear flows after Norwood operation

  Computer Methods and Programs in Biomedicine · 2025-07-19 · 1 citations

  articleOpen access

  BACKGROUND AND OBJECTIVE: Cardiovascular surgeries and mechanical circulatory support devices create non-physiological blood flow conditions that can be detrimental, especially for pediatric patients. A source of complications is mechanical red blood cell (RBC) damage induced by localized supraphysiological shear fields. To understand such complications in single ventricle patients, we introduce a multi-scale numerical model to predict hemolysis risk in idealized anatomies. METHODS: We employed our in-house CFD solver coupled with Lagrangian tracking and cell-resolved fluid-structure interaction to measure flow-induced stresses and strains on the RBC membrane. The Norwood procedure, known for its high mortality rate, is selected for its importance to single-ventricle population survival. We simulated three anatomies including 2.5 mm and 4.0 mm diameter modified Blalock-Taussig shunts (mBTS) and a 2.5 mm central shunt (CS), with hundreds of RBCs per case for statistical analysis. RESULTS: The results show that the conditions created by these surgeries can elongate RBCs by more than two-fold (3.1% of RBCs for 2.5 mm mBTS, 1.4% for 4 mm mBTS, and 8.8% for CS). Shear and areal strain metrics also reveal that CS creates the greatest deformations on the RBC membrane. These conclusions are further confirmed when strain history and different damage thresholds are considered. CONCLUSIONS: The central shunt is more hemolytic in comparison to the modified Blalock-Taussig shunt. Between the two mBTSs, the smaller diameter is slightly more prone to hemolysis. Spatial damage maps produced based on the studied metrics, highlighted hot zones that match the clinical images of shunt thrombosis, demonstrating their potential to enhance cardiac surgery outcomes.

  PublisherDOI

• Hybrid Biophysics Co-Simulation of a Percutaneous Catheter VAD within a Contractile Left Heart

  Cardiovascular Engineering and Technology · 2025-06-25 · 1 citations

  articleSenior author
  PublisherDOI

• 3d Peridynamic Modeling of Isotropic Hyperelasticity in Principal Stretches: With Application to Blood Clot Mechanics

  SSRN Electronic Journal · 2025-01-01

  preprintOpen accessSenior author
  PublisherDOI

• Multi‐Objective <scp>CFD</scp> Optimization of an Intermediate Diffuser Stage for <scp>PediaFlow</scp> Pediatric Ventricular Assist Device

  Artificial Organs · 2025-08-14 · 1 citations

  articleOpen accessSenior author

  BACKGROUND: Computational fluid dynamics (CFD) has become an essential design tool for ventricular assist devices (VADs), where the goal of maximizing performance often conflicts with biocompatibility. This tradeoff becomes even more pronounced in pediatric applications due to the stringent size constraints imposed by the smaller patient population. This study presents an automated CFD-driven shape optimization of a new intermediate diffuser stage for the PediaFlow pediatric VAD, positioned immediately downstream of the impeller to improve pressure recovery. METHODS: We adopted a multi-objective optimization approach to maximize pressure recovery while minimizing hemolysis. The proposed diffuser stage was isolated from the rest of the flow domain, enabling efficient evaluation of over 450 design variants using Sobol sequence, which yielded a Pareto front of nondominated solutions. The selected best candidate was further refined using a local T-search algorithm. We then incorporated the optimized front diffuser into the full pump for CFD verification and in vitro validation. RESULTS: We identified critical dependencies where longer blades increased pressure recovery but also hemolysis, while the wrap angle showed a strong parabolic relationship with pressure recovery but a monotonic relationship with hemolysis. Counterintuitively, configurations with fewer blades (2, 3) consistently outperformed those with more blades (4, 5) in both metrics. The optimized two-blade design enabled operation at lower pump speeds (14 000 vs. 16 000 RPM), improving hydraulic efficiency from 26.3% to 32.5% and reducing hemolysis by 31%. CONCLUSION: This approach demonstrates that multi-objective CFD optimization can systematically explore complex design spaces while balancing competing priorities of performance and hemocompatibility for pediatric VADs.

  PublisherOA PDFDOI

• Towards a Model of Thrombus Embolization: Structural Response and Failure of Blood Clots Through Peridynamics

  International Journal for Numerical Methods in Biomedical Engineering · 2025-11-01 · 1 citations

  articleSenior author

  Despite the high mortality rates associated with thromboembolic diseases, computational modeling of the physics of thromboembolism remains underdeveloped in the literature due to the inadequacy of classical finite element methods to accommodate the growth, large deformation, and fracture of blood clots, especially under the influence of fluid dynamic forces. Accordingly, we present a meshless numerical framework, employing peridynamics (PD) that readily captures the constitutive response, damage progression, and eventual failure of a blood clot. The PD framework was validated against three benchmark test cases: tensile loading of a plate with a hole, torsional loading of a column, and tensile loading of thin structural plates both with and without notches. Comparative quantitative and qualitative analysis demonstrated excellent agreement with finite element solutions generated using the commercial software ANSYS. The validated framework was then used to calibrate the peridynamic parameters to accurately reproduce the mechanical response, the cohesive bulk fracture of blood clots under tensile loading, and the debonding of blood clots from artificial surfaces, including titanium (Ti), polyurethane (PU), and polytetrafluoroethylene (PTFE). Force-displacement curves obtained using these calibrated parameters demonstrated a strong correlation with experimental data.

  PublisherDOI

• &lt;em&gt;In Vitro&lt;/em&gt; Thrombosis Test for Ventricular Assist Devices

  Journal of Visualized Experiments · 2025-03-21

  articleSenior author

  The risk of thrombosis remains a significant concern in the development and clinical use of ventricular assist devices (VADs). Traditional assessments of VAD thrombogenicity, primarily through animal studies, are costly and time-consuming, raise ethical concerns, and ultimately may not accurately reflect human outcomes. To address these limitations, we developed an aggressive in vitro testing protocol designed to provoke thrombosis and identify potential high-risk areas within the blood flow path. This protocol, motivated by the work of Maruyama et al., employs a modified anticoagulation strategy and utilizes readily available components, making it accessible to most laboratories conducting in vitro blood testing of VADs. We demonstrated the utility of this method through iterative testing and refinement of a miniature magnetically levitated pediatric VAD (PediaFlow PF5). The method has been effective in identifying thrombogenic hotspots caused by design and manufacturing flaws in early VAD prototypes, enabling targeted improvements before advancing to animal studies. Despite its limitations, including the absence of pulsatile flow and the influence of donor blood characteristics, this protocol serves as a practical tool for early-stage VAD development and risk mitigation.

  PublisherDOI

Recent grants

• NIH Grant R41HL077028

  NIH · $200k · 2008

• CORA_TM_A Personalized Cardiac Counselor for Optimal Therapy

  NIH · $3.5M · 2018–2020

• CHRiSS: Cardiac Health Risk Stratification System

  NIH · $150k · 2013–2014

• NIH Grant R41HL082251

  NIH · $237k · 2007

• Multiscale Model of Thrombosis in Artificial Circulation

  NIH · $8.5M · 2009–2026

Frequent coauthors

• Marina V. Kameneva

  185 shared

• Harvey S. Borovetz

  University of Pittsburgh

  125 shared

• Robert L. Kormos

  Abbott (United States)

  122 shared

• Bartley P. Griffith

  University of Maryland, Baltimore

  79 shared

• William R. Wagner

  University of Alabama at Birmingham

  70 shared

• Greg W. Burgreen

  63 shared

• Mary J. Watach

  University of Pittsburgh

  61 shared

• Philip Litwak

  University of Pittsburgh

  58 shared

Labs

• Antaki LabPI

Education

• PhD, Mechanical Engineering

  University of Pittsburgh

  2001

Awards & honors

• Steven Fenves Award for Systems Re