Association of Systemic Inflammatory Response Syndrome With Cardiovascular Events After Mitral Transcatheter Edge-to-Edge Repair.

Background: Systemic inflammatory response syndrome (SIRS) following cardiovascular interventions is associated with adverse events during hospitalization and follow-up. Mitral transcatheter edge-to-edge repair is increasingly utilized for treatment of mitral regurgitation (MR). We investigated whether SIRS following mitral transcatheter edge-to-edge repair may occur and be associated with adverse clinical outcomes.

Methods and results: A total of 158 consecutive patients with severe MR undergoing mitral transcatheter edge-to-edge repair were studied. SIRS was defined by leukocytosis (≥12 × 10⁹/L) and fever (≥38 °C) within 48 hours after intervention. Baseline inflammation was measured by absolute neutrophil and lymphocyte counts and neutrophil-lymphocyte ratio. The primary end point of major cardiovascular events was the composite of nonfatal myocardial infarction, nonfatal stroke, and all-cause death. Recurrent MR at follow-up was also recorded. The mean patient age was 80.8±8.8 years. Forty-four (27.9%) developed SIRS. Neutrophil-lymphocyte ratio correlated with onset of leukocytosis and fever (P=0.04). During a median follow-up of 12.5 (5.4-17.4) months, the primary end point occurred in 27 (17.1%) patients (6 myocardial infarction, 5 strokes, and 16 deaths). Patients with SIRS more often had severe MR (79.5% versus 62.7%, P=0.02) at follow-up. After adjustment for pertinent variables, SIRS (HR 2.73 [95% CI, 1.08-6.86]; P=0.03) was independently associated with major cardiovascular events.

Conclusions: SIRS after mitral transcatheter edge-to-edge repair is a strong independent predictor of major cardiovascular events. Closer follow-up is warranted because patients with SIRS have more severe MR at follow-up.