At the European Society of Cardiology (ESC) Congress 2025, cardiologists from District Hospital of Santarém, Portugal, presented real-world evidence on which patients benefit most from cardiac resynchronization therapy (CRT) upgrades.

Right ventricular (RV) pacing, while lifesaving, can trigger electrical and mechanical desynchrony, leading to left ventricular dysfunction in up to 30% of patients. Upgrading to CRT has been shown to counteract these harmful effects, but response remains inconsistent, with 20–40% of patients considered non-responders.

In this single-center retrospective study, 55 patients with heart failure and reduced left ventricular ejection fraction (LVEF) underwent CRT revision between 2015 and 2024. Response was defined as an LVEF improvement of at least 5% and a one-class gain in New York Heart Association (NYHA) status.

Results showed that 64% of patients responded to CRT upgrade, with an average LVEF increase of 10.7% and marked improvement in functional class (49% reached NYHA I at follow-up). 

By contrast, gender, cardiac rhythm, device type, or time since first implantation did not influence outcomes.

The study highlights the feasibility and impact of CRT upgrades even in district hospital settings, reinforcing their role in improving real-world heart failure management across diverse healthcare environments.