Positive Response to Cardiac Resynchronization Therapy - The Role of NT-proBNP

Cardiac resynchronization therapy (CRT) became available in the late 1990s, offering a safe and effective treatment for patients suffering from heart failure with left ventricular systolic dysfunction (LVEF<35%) and electrical dyssynchrony (QRS duration ≥ 120 ms) . However, positive clinical response is observed in only 60- 70% of the treated population, and significant echocardiographic remodeling is observed in 50-60% of the treated population . The reasons for “non-response” seem to be multifactorial, while different studies have used different definitions of echocardiographic and clinical factors to indicate positive response . Using different criteria for response in different studies makes it difficult to make head-to-head comparison of outcome and results as different subpopulations of “responders” may be examined, and there may thus be different implications for clinical outcomes.

 Additional data from biochemical markers such as NT-proBNP carries a prognostic value in CRT patients, and postoperative reduction has been shown to correlate to reduced long-term mortality . Monitoring NTproBNP may therefore help more easily identify primarily the nonresponders for early intervention and more intensive care with a view to improving their quality of life and clinical outcome. Our study sought to compare baseline NT-proBNP levels in relation to clinical and echocardiographic positive response to CRT, and also to assess the association between the extent of change in NT-proBNP levels with echocardiographic and/or clinical response.