The RETENTION consortium announces the successful completion of the multi-centric patient recruitment phase, achieving an important milestone for collaborative research on cardiology and heart transplantation across Europe.

Between May 2024 and November 2025, the study enrolled 390 adult participants across six major clinical centres, creating a robust cohort of patients with symptomatic chronic heart failure (HF), implanted left ventricular assist devices (LVADs), and orthotopic heart transplants (HTX).

Key highlights

RECRUITED COHORT: 390 adult patients with symptomatic chronic heart failure, implanted LVADs, or post-orthotopic heart transplantation enrolled across six clinical centres in Greece, Spain, Italy and Germany.

TIMELINE: Recruitment opened in May 2024 and closed in November 2025.

PARTICIPATING INSTITUTIONS:

  • Greece: Onassis Cardiac Surgery Center (OCSC); National and Kapodistrian University of Athens / ATTIKON Hospital (NKUA)
  • Spain: Servicio Madrileño de Salud (SERMAS) – Hospital Universitario Ramón y Cajal (HURC); Hospital Universitario Puerta de Hierro (HUPH)
  • Italy: Alma Mater Studiorum – Università di Bologna (UNIBO); Azienda Ospedaliero-Universitaria di Bologna Policlinico Sant’Orsola-Malpighi (AZIENDA)
  • Germany: Medizinische Hochschule Hannover (MHH)

COLLABORATION: The recruitment success reflects coordinated efforts among the project’s lead hospitals, research teams, clinical staff and participating patients across partner countries.

Impact & study focus

Completed recruitment enables RETENTION to move into the project’s next stage: finalising daily, environmentally aware remote patient monitoring, and testing targeted AI-enabled interventions informed by patient-centred data continuously collected outside hospital settings and at regular follow-ups.

Outcome measures for the forthcoming phase include all-cause and cardiovascular mortality, heart failure hospitalisations and emergency room visits, and patient-reported quality of life across the three study populations (HF, LVAD, HTX).

We are thrilled to having achieved a significant number of participants enrolled in the Clinical Trial, despite the various recruitment challenges encountered. Applying the machine learning models that have been developed in the project, on the participants’ data until the end of the follow-up in September 2026, is our next major milestone and a challenging innovation. We are eager to see the outcomes of this innovative clinical decision support flow offered to the clinicians, and measure the impact of the AI-enabled interventions suggested by the algorithms. Mostly, we are eager to measure any positive clinical outcomes on our patient cohorts as a result of the RETENTION platform and the applied analytics.

Maria Haritou, Project Coordinator

Next steps

With recruitment closed, the RETENTION project will transition to the monitoring completion and outcomes’ evaluation phase, during which analysis of the collected data, algorithm-driven notifications and clinical intervention pathways will be implemented and assessed.

The results of the analysis will be shared with patient and professional associations, healthcare administrators, policy makers, funders, and the scientific community in the coming months.

retention-project.eu, 19 November 2025