Monocyte Subsets in Patients with Chronic Heart Failure Treated with Cardiac Resynchronization Therapy

Background: The exact role of individual inflammatory factor in heart failure with reduced ejection fraction (HFrEF) remains elusive. The study aimed to evaluate three monocyte subsets (classical-CD14(++)CD16(-), intermediate-CD14(++)CD16(+), and nonclassical-CD14(+)CD16(++)) in HFrEF patients and to assess the effect of the cardiac resynchronization therapy (CRT) on the changes in monocyte compartment. Methods: The study included 85 patients with stable HFrEF. Twenty-five of them underwent CRT device implantation with subsequent 6-month assessment. The control group consisted of 23 volunteers without HFrEF. Results: The analysis revealed that frequencies of non-classical-CD14(+)CD16(++) monocytes were lower in HFrEF patients compared to the control group (6.98 IQR: 4.95-8.65 vs. 8.37 IQR: 6.47-9.94; p = 0.021), while CD14(++)CD16(+) and CD14(++)CD16(-) did not differ. The analysis effect of CRT on the frequency of analysed monocyte subsets 6 months after CRT device implantation showed a significant increase in CD14(+)CD16(++) (from 7 IQR: 4.5-8.4 to 7.9 IQR: 6.5-9.5; p = 0.042) and CD14(++)CD16(+) (from 5.1 IQR: 3.7-6.5 to 6.8 IQR: 5.4-7.4; p = 0.017) monocytes, while the frequency of steady-state CD14(++)CD16(-) monocytes was decreased (from 81.4 IQR: 78-86.2 to 78.2 IQR: 76.1-81.7; p = 0.003). Conclusions: HFrEF patients present altered monocyte composition. CRT-related changes in the monocyte compartment achieve levels observed in controls without HFrEF.

Automated summary

The study revealed altered monocyte composition in HFrEF patients, with CRT leading to changes in monocyte subsets that reached levels similar to controls without HFrEF.