Galectin-3 predicts response and outcomes after cardiac resynchronization therapy.

BACKGROUND

Cardiac resynchronization therapy (CRT) reduces symptoms, morbidity and mortality in chronic heart failure patients with wide QRS complexes. However, approximately one third of CRT patients are non-responders. Myocardial fibrosis is known to be associated with absence of response. We sought to see whether galectin-3, a promising biomarker involved in fibrosis processes, could predict response and outcomes after CRT.

METHODS

Consecutive patients eligible for implantation of a CRT device with a typical left bundle branch block ≥ 120 ms were prospectively included. Serum Gal-3 level, Selvester ECG scoring, and cardiac magnetic resonance with analysis of late gadolinium enhancement (LGE) were ascertained. Response to CRT was defined by a composite endpoint at 6 months: no death, nor hospitalization for major cardiovascular event, and a significant decrease in left ventricular end-systolic volume of 15% or more.

RESULTS

Sixty-one patients were included (age 61 ± 5 years, ejection fraction 27 ± 5%), 59% with non-ischemic cardiomyopathy. At 6 months, 49 patients (80%) were considered responders. Responders had a lower percentage of LGE (8 ± 13% vs 22 ± 16%, p = 0.006), and a trend towards lower rates of galectin-3 (16 ± 6 ng/mL vs 19 ± 8 ng/mL, p = 0.13). LGE ≥ 14% and Gal-3 ≥ 22 ng/mL independently predicted response to CRT (OR = 0.17 [0.03-0.62], p = 0.007, and OR = 0.11 [0.02-0.04], p < 0.001, respectively). At 48 months of follow-up, 12 patients had been hospitalized for a major cardiovascular event or had died. Galectin-3 level predicted long-term outcomes (HR = 3.31 [1.00-11.34], p = 0.05).

CONCLUSIONS

Gal-3 serum level predicts the response to CRT at 6 months and long-term outcomes in chronic heart failure patients.