Factors Associated with Non-Response to Cardiac Resynchronization Therapy: Insights from a Real-World, Single-Center Study

Context and objective. Cardiac resynchronization therapy (CRT) is applied to symptomatic treated patients with HFrEF and wide QRS. Despite its established benefits, a significant percentage of patients don’t respond positively to CRT based on the assessed criteria. The aim of this study was to determine the frequency of CRT non-response and identify its associated factors among heart failure patients who underwent CRT implantation. Methods. A historical cohort study was conducted on heart failure patients who received CRT at the Saint-Quentin Hospital Center (CHSQ) from January 1, 2020, to September 30, 2022. The data collected included demographics, clinical characteristics, electrocardiographic, echocardiographic, and magnetic resonance imaging measurements, biological markers, and follow-up results. Non-response to CRT was defined as the failure to improve left ventricular ejection fraction (LVEF) by more than 10% six months after CRT. We used multivariate logistic regression analysis to identify variables independently associated with non-response to CRT. Results. Out of 82 patients, 29 (35.4%) were categorized as non-responders. Mean LVEF increased from 27.5% to 40% after CRT. Factors associated with non-response encompassed: MRI fibrosis (aOR=3.99; p=0.007), male sex (aOR=3.04; p=0.006), low and medium starting dose of Sacubitril-valsartan respectively (aOR=3.02; p=0.013; aOR=2.03; p=0.032) and history of ischemic cardiac heart disease (aOR=2.4; p=0.037). Conclusion. The non-response to CRT is common and is attributed to the patient's specific history, clinical, behavioral and underlying pathophysiological conditions. These findings underscore the importance of improving patient selection and implementing personalized treatment strategies. Future studies should focus on improving patient selection criteria, optimizing CRT techniques, exploring new biomarkers, assessing long-term outcomes and exploring innovative therapies. Keywords: Cardiac resynchronization therapy, heart failure, non-response, predictors, echocardiography, biomarkers Received: October 4th, 2024 Accepted: February 2nd, 2025 https://dx.doi.org/10.4314/aamed.v18i2.2