Clinical outcomes of conventional surgery versus MitraClip® therapy for moderate to severe symptomatic mitral valve regurgitation in the elderly population: an institutional experience

Background: The aim of this study was to compare treatment of moderate to severe symptomatic mitral regurgitation (MR) with either conventional surgery or the mitral valve edge-to-edge device (MitraClip®) in very elderly patients. The newly introduced MitraClip device has demonstrated promising acute results in treating this patient cohort. Also noteworthy is the fact that patients who otherwise would have been denied surgery are increasingly referred for treatment with the MitraClip device. We sought to review our institutional experience, comparing outcomes in both surgical and MitraClip arms of treatment in the elderly population with symptomatic MR.

Methods: From October 2008 through October 2014, 136 consecutive patients aged ≥ 80 with moderate to severe symptomatic MR were scheduled for either conventional surgery or MitraClip intervention. 56 patients ≥ 80 were operated for symptomatic MR and 80 patients ≥ 80 were treated with the mitraClip device. Patients suitable for this study were identified from our hospital database. Patients ≥80 with moderate/severe symptomatic MR treated with either conventional surgery or the MitraClip device were eligible for our analysis. We compared the surgical patient cohort with the mitraClip patient cohort after eliminating patients that did not meet our inclusion criteria. Forty-two patients were identified from the conventional cohort who were then compared with 42 patients from the mitraClip cohort. Forty-two patients (50%) underwent mitral valve repair or replacement (40.5% functional MR, 59.5% organic/mixed MR) and 42 patients (50%) underwent MitraClip intervention (50% functional MR, 50% organic/mixed MR). Associated procedures in the conventional surgical group were myocardial revascularization 38%, pulmonary vein ablation 23.8%, left atrial appendage resection 52.4% and PFO occlusion 11.9%.

Results: Patients who underwent MitraClip treatment were though slightly older but the differences did not attain statistical significance (mean, 82.2 ± 1.65 vs 81.7 ± 1.35 years, p = 0,100), had lower LVEF (mean, 47.6 ± 14.2 vs 53.4 ± 14.3, p = 0.072), lower logistic EuroScore II (mean, 11.3 ± 5.63 vs 12.1 ± 10.6, p = 0.655) but higher STS risk score (mean, 11.8 ± 6.7 vs 8.1 ± 5.6, p = 0.008) respectively compared to surgical patients. Procedural success was 100% vs 96% in surgery and MitraClip groups respectively. Thirty -day mortality was 7.1% vs 4.8% (p = 1.000) in surgery and MitraClip group respectively. Residual postoperative MR ≥2 at discharge was present in none of the patients treated surgically, whereas this was the case in 10 (23.8%) patients treated with the MitraClip device. At 1 year a cumulative number of four (9.52%) patients died in the surgical group vs 9 (21.4%) patients who died in the MitraClip group.

Conclusions: Elderly patients presenting with moderate to severe symptomatic MR may either be treated by conventional surgery or with the MitraClip device with acceptable acute outcomes. The decision for treatment with the MitraClip device should not depend on age alone rather on cumulative risk of conventional surgery. Concomitant cardiac pathologies, often times treated simultaneously during surgery for symptomatic MR may be omitted, if patients are scheduled outright to MitraClip treatment. The effect of concomitant cardiac pathologies left untreated at the time of interventional mitral valve repair on outcome after MitraClip therapy remain widely unknown.