Significance of Spontaneous Echocardiographic Contrast in Transcatheter Edge-to-Edge Repair for Mitral Regurgitation

Background: Spontaneous echocardiographic contrast (SEC) in the left atrium can occur with transcatheter edge-to-edge repair (TEER), but the clinical significance is unknown.Methods: The authors examined the clinical association of the procedural appearance of SEC in 316 patients (median age, 82 years; interquartile range, 76-86 years; 43.4% women) undergoing TEER with the MitraClip for mitral regurgitation. Acute, 30-day, and 2-year clinical outcomes were analyzed.Results: SEC was common, occurring following device implantation in 106 patients (34%). Although the occur-rence of SEC was not related to clinical characteristics, such as atrial fibrillation, anticoagulant use, or left ven-tricular function, there was a strong relation to beneficial outcomes with TEER. The frequency of optimal reduction in mitral regurgitation was higher in patients who had SEC (99.1% vs 72.9%, P < .001). Survival was greater, with a 2-year estimate for freedom from all-cause mortality of 88.4% versus 71.5% (log-rank P = .004). Importantly, the higher survival observed in patients with SEC was present without increased rates of procedural complications or stroke and remained significant in multivariate analyses that adjusted for base-line clinical and echocardiographic variables (P = .01).Conclusions: The occurrence of SEC in patients with TEER is associated with beneficial acute and intermediate-term outcomes. (J Am Soc Echocardiogr 2023;36:87-95.)