Back to Annual Meeting Program

OBJECTIVE: Various transcatheter approaches to mitral valve disease have been clinically employed for patients carrying a high risk for surgery. We sought to assess the impact of etiology of MR on functional and clinical results after MitraClip therapy in a cohort of symptomatic patients with severe MR not amenable to surgery.
METHODS: Between 9/2008 and 04/2011, a total of 226 consecutive patients underwent MitraClip implantation for either functional MR (group A; n=143; 63%) or degenerative/mixed MR (group B; n=83; 37%). Risk for mitral valve surgery was considered high by means of a logistic EuroScore of 31±19% and 28±19% (p=0.2536), respectively. Preprocedural left ventricular ejection fraction was reduced to 38±14% and 54±12% (p<0.0001), respectively.
RESULTS: MitraClip implantation was successful in 138 (97%) patients with functional and 69 (83%) patients with degenerative/mixed MR (p=0.0008), respectively. Most of these patients (group A: n=96 (70%); group B: n=37 (54%); p=0.0311) were treated with a single clip, whereas 42 (30%) patients in group A and 32 (46%) patients in group B received ≥2 clips. Preprocedural MR severity was gade 3+ (group A: n=86 (62%); group B: n=36 (52%)) or grade 4+ (group A: n=52 (38%); group B: n=33 (48%)) (p=0.1792), whilst MR severity at discharge was grade 1+ (group A: n=62 (45%); group B: n=22 (32%)) or grade 2+ (group A: 76 (55%), group B: n=47 (68%)) (p=0.0744). NYHA functional class at baseline and at time of discharge did not differ between both groups. Thirty-day mortality was 4.8% in group A and 2.4% in group B (p=0.358), respectively.
CONCLUSIONS: MR of functional origin is associated with significantly higher technical success and requires a significantly lower number of clips for successful procedure as opposed to degenerative/mixed MR. Interventional mitral valve repair is probably more likely to be successful in functional MR compared to degenerative/mixed MR, which is still a domain of surgical mitral valve reconstruction.