The Role of the Systemic Immune-Inflammation Index in Predicting Response to Cardiac Resynchronization Therapy

Objective: Cardiac resynchronization therapy (CRT) is a reliable treatment modality in patients with systolic dysfunction. However, not every patient appears to benefit from CRT. The systemic immune inflammation index (SII) is closely linked to the poor prognosis of various cardiovascular disorders. However, there is no study investigating whether SII has predictive value in determining response to CRT in dilated cardiomyopathy patients. Therefore, we intend to investigate the association between SII and response to CRT. Methods: A total of 220 patients (mean age 61.2±10.8 years; 120 men) implanted with CRT were involved in this study. Echocardiographic and laboratory measurements were evaluated prior to CRT. Response to CRT was determined as a≥ 15% decrease in left ventricular end-systolic volume at one-year follow-up. Results: Patients grouped as CRT responders and non-responders. Of these, 143 (64.6%) were considered to be CRT responders, while the remaining 77 (33.4%) were non-responders. Female sex (OR: 3.823, CI: 1.568-9.324 p=0.003), QRS duration (OR: 1.224, CI: 1.158-1.335 p 825 estimated no response to CRT with 80% sensitivity and 75% specificity. Conclusions: SII was associated with unresponsiveness to CRT. Therefore, it may be used to determine optimal patient selection for CRT implantation in routine clinical practice.