Second cross-clamp in less invasive mitral valve repair for degenerative mitral regurgitation: Predictors and outcomes.

Abstract

To evaluate the incidence, echocardiographic patterns, operative strategies, and results of patients receiving a second cross-clamping in the large population of the Mini Mitral International Registry. We examined 4577 patients with degenerative mitral regurgitation (MR) who underwent less invasive mitral repair. Patients with nondegenerative disease, planned valve replacement, and surgery without cross-clamping were excluded. Multivariable logistic regression model was applied to investigate predictors of second cross-clamping and the relationship between second cross-clamping and outcomes. Second cross-clamping was used in 128 cases (2.8%). Reasons for re-cross-clamping included residual pathology in 71.9% of the patients (n = 92) and systolic anterior motion (SAM) in 28.1% (n = 36). Re-repair was performed in 104 patients (81.3%), and replacement was performed in 24 (18.7%). After re-repair, 92 patients (94.9%) had no or mild MR, 4 patients (4.1%) had moderate MR, and 1 patient (1%) had severe MR. A residual SAM was observed in 2 patients (2.3%). Bileaflet prolapse (odds ratio [OR], 2.21) and predicted risk of SAM (OR, 3.04) were identified as risk factors for second cross-clamping. No association between second cross-clamping and mortality or major postoperative complications was found; however, second cross-clamping was associated with an increased risk of respiratory insufficiency (OR, 4.6) and longer intensive care unit (ICU) stay (β = 0.35). Second cross-clamping after less invasive mitral repair is infrequent but may be required, particularly in patients with bileaflet pathology or at increased risk of SAM. Most re-repairs were successful, with <20% of patients requiring replacement. Second cross-clamping was associated with higher risk of respiratory insufficiency and prolonged ICU stay.