Afterload Mismatch After MitraClip Implantation: Intraoperative Assessment and Prognostic Implications.

AIM: To evaluate the acute hemodynamic effects after MitraClip implantation and to identify predictors of afterload mismatch and its prognostic implications.

METHODS

Acute hemodynamic effects were assessed intraoperatively by right heart catheterization and by transesophageal echocardiography before and after MitraClip implantation in 62 consecutive patients with severe mitral regurgitation (MR) (functional MR, 73.8%; EuroScore 2, 7.1 ± 4.9%; left ventricular ejection fraction [LVEF], 36 ± 15%; New York Heart Association class III/IV, 65%). Afterload mismatch was defined as a >15% decrease in LVEF (acute LV depression) or a >15% increase in LV end-diastolic volume (acute adverse LV remodeling). Patients were followed over a period of 24 months (mean, 18 ± 3 months) with all-cause mortality as the primary endpoint.

RESULTS

Successful MitraClip implantation with residual MR ≤2 was achieved in 85% of patients. Acute LV depression was observed in 23% of patients, and acute adverse LV remodeling was observed in 15% of patients. Acute adverse LV remodeling occurred in 40% of patients with EuroScores >12 vs in 10% of patients with EuroScores ≤12 (P=.02). Although acute adverse LV remodeling was well tolerated in the acute phase, it was associated with a higher mortality rate during follow-up (62% vs 26%; log-rank P=.04). In a multivariate model, EuroScore 2, but not afterload mismatch, was the most important prognostic risk factor, with an adjusted hazard ratio of 1.1 (95% confidence interval, 1.0-1.2).

CONCLUSION

Afterload mismatch, as assessed intraoperatively, is not uncommon after MitraClip implantation in patients with impaired LV function and is a risk marker of poor clinical outcome.