Abstract
OBJECTIVES
Among patients undergoing transcatheter mitral valve repair with the MitraClip device, a relevant proportion (2–6%) requires open mitral valve surgery within 1 year after unsuccessful clip implantation. The goal of this review is to pool data from different reports to provide a comprehensive overview of mitral valve surgery outcomes after the MitraClip procedure and estimate in-hospital and follow-up mortality.
METHODS
All published clinical studies reporting on surgical intervention for a failed MitraClip procedure were evaluated for inclusion in this meta-analysis. The primary study outcome was in-hospital mortality. Secondary outcomes were in-hospital adverse events and follow-up mortality. Pooled estimate rates and 95% confidence intervals (CIs) of study outcomes were calculated using a DerSimionian–Laird binary random-effects model. To assess heterogeneity across studies, we used the Cochrane Q statistic to compute I2 values.
RESULTS
Overall, 20 reports were included, comprising 172 patients. Mean age was 70.5 years (95% CI 67.2–73.7 years). The underlying mitral valve disease was functional mitral regurgitation in 50% and degenerative mitral regurgitation in 49% of cases. The indication for surgery was persistent or recurrent mitral regurgitation (grade >2) in 93% of patients, whereas 6% of patients presented with mitral stenosis. At the time of the operation, 80% of patients presented in New York Heart Association functional class III–IV. Despite favourable intraoperative results, in-hospital mortality was 15%. The rate of periprocedural cerebrovascular accidents was 6%. At a mean follow-up of 12 months, all-cause death was 26.5%. Mitral valve replacement was most commonly required because the possibility of valve repair was jeopardized, likely due to severe valve injury after clip implantation.
CONCLUSIONS
Surgical intervention after failed transcatheter mitral valve intervention is burdened by high in-hospital and 1-year mortality, which reflects reflecting the high-risk baseline profile of the patients. Mitral valve replacement is usually required due to leaflet injury.
Keywords: Mitral regurgitation, Transcatheter mitral valve repair, Percutaneous edge-to-edge, Failure, Surgery
Percutaneous edge-to-edge mitral valve repair with the MitraClip device (Abbott, Santa Clara, CA, USA) is a widely adopted treatment for mitral regurgitation (MR) in patients deemed high surgical risk or inoperable.
INTRODUCTION
Percutaneous edge-to-edge mitral valve repair with the MitraClip device (Abbott, Santa Clara, CA, USA) is a widely adopted treatment for mitral regurgitation (MR) in patients deemed high surgical risk or inoperable. Nevertheless, procedural failure and recurrent MR are independent negative prognostic factors [1], and a number of patients (2–6%) [1, 2] require open mitral valve surgery within 1 year after an unsuccessful clip implantation. To date, available evidence regarding preoperative details, procedural and in-hospital outcomes and subsequent follow-up of these patients is mainly derived from isolated and fragmented clinical experiences. The goal of this review was to pool data from different reports to provide a comprehensive overview of mitral valve surgery outcomes after a failed MitraClip procedure and estimate the rates of in-hospital mortality and adverse events as well as the 1-year all-cause mortality.
METHODS
Search strategy
In June 2019, 2 authors (F.M., L.B.) independently searched PubMed, Embase, BioMed Central and Google Scholar using a combination of the following search terms: ‘MitraClip’, ‘cardiac surgery’, ‘percutaneous mitral valve repair’, ‘transcatheter mitral valve repair’, ‘failure’, ‘mitral valve replacement’, ‘cardiac surgery’. Backward snowballing (review of references from identified articles and pertinent reviews) was also performed. This network meta-analysis was reported in accordance with the preferred reporting items for systematic reviews and meta-analyses statement; the checklist for this statement is available in Supplementary Material, Table S1.
Study selection and data extraction
All published clinical studies reporting on surgical interventions for failed MitraClip were evaluated for’ inclusion in this meta-analysis. All authors independently assessed identified studies for possible inclusion. Non-relevant articles were excluded based on the title and abstract. Two investigators (F.M., L.B.) independently extracted data on study design, measurements, patient characteristics and outcomes using a standardized data extraction form. Conflicts regarding inclusion and data extraction were discussed and resolved with another investigator (A.B.). Data collection included authors, year of publication, inclusion and exclusion criteria, sample size, baseline clinical features of patients, details of the surgical operation as well as in-hospital and follow-up outcomes, as available. To improve data extraction, Supplementary Materials and pooled analyses pertinent to the study of interest were also examined.
Risk of bias within individual studies
Two independent reviewers (F.M., L.B.) assessed the risk of bias (low, intermediate or high) of the included studies using the Cochrane Collaboration tool [3]. The results are available in Supplementary Material, Table S2. All case reports and case series including ≤4 patients were considered at high risk of bias.
Study outcome
The primary study outcome was in-hospital mortality. Secondary outcomes were in-hospital adverse events [acute heart failure (HF), stroke, acute kidney injury] and follow-up mortality.
Statistical analysis
Rates are expressed as percentage of number of subjects with valid data. Pooled estimate rates and 95% confidence intervals (CIs) of study outcomes were calculated using a DerSimionian–Laird binary random-effects model [4]. To assess heterogeneity across studies, we used the Cochrane Q test to compute I2 values: <25%, 25–50% or >50% indicated low, moderate or high heterogeneity, respectively [5]. Statistical significance was set at P-value <0.05 (2-sided). Statistical analyses were conducted with Comprehensive Meta-Analysis v.2 (Biostat Inc., Englewood, NJ, USA).
RESULTS
Study population
We included 20 reports [6–25] (9 cohort studies including ≥4 patients) (Fig. 1) for a total of 172 patients who underwent a surgical mitral intervention after a failed MitraClip procedure (Table 1).
Figure 1:
CONSORT diagram of included studies.
Table 1:
Included studies with reported baseline preoperative risk assessment
| Author | Year | Sample size, n | EuroSCORE II, n, mean ± SD or median (range) | Pulmonary hypertension, n (%) | Pulmonary artery pressure (mmHg), mean ± SD | CKD, n (%) |
|---|---|---|---|---|---|---|
| Dang et al. [6] | 2005 | 6 | NA | NA | NA | NA |
| Rogers et al. [7] | 2009 | 4 | NA | NA | NA | NA |
| Argenziano et al. [8] | 2010 | 32 | NA | NA | NA | NA |
| Conradi et al. [9] | 2011 | 6 | 21.6 ± 8 | NA | NA | 4 (66.6) |
| Takahashi et al. [10] | 2012 | 1 | NA | NA | NA | NA |
| Rose et al. [11] | 2012 | 1 | 7 | NA | NA | NA |
| Chanda et al. [12] | 2012 | 1 | 4.8 | Yes | 37 | Yes |
| Pope et al. [13] | 2013 | 1 | 5 | Yes | 90 | Yes |
| Wendeborn et al. [14] | 2013 | 1 | 19 | NA | NA | Yes |
| Alozie et al. [15] | 2014 | 13 | 8 ± 5 | NA | 54 ± 19 | 7 (54) |
| Monsefi et al. [16] | 2014 | 6 | 12 ± 7 | NA | NA | 4 (66.6) |
| Cockburn et al. [17] | 2014 | 1 | 23 | Yes | 70 | NA |
| Caussin et al. [18] | 2015 | 1 | NA | NA | NA | NA |
| Calafiore et al. [19] | 2015 | 3 | 11.4 ± 3.8 | 2 (66.6%) | 42.5 ± 3.5 | NA |
| Saito et al. [20] | 2015 | 2 | 4.9 | 2 (100) | NA | 1 (50%) |
| Frerker et al. [21] | 2015 | 1 | 25.3 | Yes | NA | Yes |
| Geidel et al. [22] | 2016 | 33 | 26.5 (18.7–37.9) | NA | NA | 20 (60.6) |
| Elhmidi et al. [23] | 2016 | 25 | NA | NA | NA | NA |
| Takayuki et al. [24] | 2019 | 25 | 11 (6.7–24.3) | NA | 50 ± 14 | 14 (56) |
| Mkalaluh et al. [25] | 2019 | 9 | NA | NA | NA | 4 (44) |
CKD: chronic kidney disease; NA: not available; SD: standard deviation.
The mean age was 70.5 years (95% CI 67.2–73.7) and 57% of the patients were men. Underlying mitral valve disease was functional MR in 50% and degenerative MR in 49% of cases. A history of (HF) and atrial fibrillation was reported in 73% and 50% of patients, respectively. The mean left ventricular ejection fraction was 41% (95% CI 28.5–53.1). At the time of the operation, most patients presented with signs of HF, with nearly 80% of them being in New York Heart Association functional class III–IV. Although limited by missing data in some reports, the overall preoperative risk was high as estimated by the EuroSCORE II and confirmed by the high prevalence of concomitant pulmonary hypertension and chronic kidney disease (Table 1).
The most common indication for surgery was persistent or recurrent MR (grade >2) in 93% of cases, whereas in 6% it was mitral stenosis. Partial clip detachment and loss of leaflet insertion were observed in 31% and 17% of patients, respectively.
Surgical procedures
Surgical interventions were performed at highly heterogeneous follow-up times, at a median of 330 days (95% CI 138–522), whereas 12 patients needed urgent surgical conversion at the time of the index transcatheter intervention. Although mitral valve repair had been planned in two-thirds of the patients, more than 60% of them eventually underwent mitral valve replacement, mostly with a bioprosthetic valve (a mechanical valve was implanted in only 3 cases). Notably, concomitant surgical procedures were performed in 57% of patients, including tricuspid valve repair in 32% and atrial septal defect closure in 41%.
In-hospital outcomes
Mortality outcomes as described by each study are reported in Table 2. Data on intraoperative outcomes were available for all studies and were favourable—only 2 intraoperative deaths were reported. Nevertheless, based on pooled data from 123 patients, in-hospital mortality was 15% (Table 3). Overall, 42% of patients needed inotropic support; 15% had refractory HF, 4 of whom required extracorporeal membrane oxygenation support. Three patients died of complications of sepsis. The rate of periprocedural cerebrovascular accidents was 6%. Notably, heterogeneity for all intrahospital outcomes was low.
Table 2:
Included studies with reported outcomes
| Author | Year | Sample size, n | In-hospital deaths, n (%) | Follow-up deaths, n (%) | Death time (months) | Follow-up time (months), mean ± SD |
|---|---|---|---|---|---|---|
| Dang et al. [6] | 2005 | 6 | No | NA | NA | |
| Rogers et al. [7] | 2009 | 4 | No | No | 6 ± 4 | |
| Argenziano et al. [8] | 2010 | 32 | NA | NA | NA | |
| Conradi et al. [9] | 2011 | 6 | 1 (16.6) | 1 (16.6) | 9 ± 7 | |
| Takahashi et al. [10] | 2012 | 1 | No | NA | NA | |
| Rose et al. [11] | 2012 | 1 | No | No | 8 | |
| Chanda et al. [12] | 2012 | 1 | No | NA | NA | |
| Pope et al. [13] | 2013 | 1 | No | No | 4 | |
| Wendeborn et al. [14] | 2013 | 1 | No | No | 3 | |
| Alozie et al. [15] | 2014 | 13 | 1 (7.6) | 3 (23.0) | 8; 21 | 10 ± 7 |
| Monsefi et al. [16] | 2014 | 6 | 2 (33.3) | NA | NA | |
| Cockburn et al. [17] | 2014 | 1 | Yes | |||
| Caussin et al. [18] | 2015 | 1 | NA | NA | NA | |
| Calafiore et al. [19] | 2015 | 3 | No | No | 8 ± 2 | |
| Saito et al. [20] | 2015 | 2 | No | NA | NA | |
| Frerker et al. [21] | 2015 | 1 | No | No | 2 | |
| Geidel et al. [22] | 2016 | 33 | 3 (9.0) | 13 (39.3) | <8 | 25 ± 7 |
| Elhmidi et al. [23] | 2016 | 25 | 4 (16.0) | 5 (20.0) | 2 | 2 |
| Takayuki et al. [24] | 2019 | 25 | 8 (32.0) | 8 (32.0) | NA | 13 |
| Mkalaluh et al. [25] | 2019 | 9 | 3 (33.3) | 3 (33.3) | NA | 12 |
NA: not available; SD: standard deviation.
Table 3:
Pooled analysis
| Results | Observed | Pooled estimate (95% CI) | I 2 | Q | P-value for heterogeneity |
|---|---|---|---|---|---|
| Baseline characteristics | |||||
| Age (years) | 69.5 ± 17.7 | 70.5 (67.2–73.7) | 73.4 | 37.700 | <0.001 |
| Men (%) | 57.2 (79/138) | 57.6 (49.8–65.4) | 0 | 8.648 | 0.951 |
| NYHA ≥3 (%) | 79.6 (98/123) | 81.7 (68.6–94.9) | 88.8 | 107.373 | <0.001 |
| History of HF | 72.9 (70/96) | 75.0 (60.8–89.1) | 71.2 | 34.702 | <0.001 |
| LVEF (%) | 39.2 ± 22.7 | 40.8 (28.5–53.1) | 99.3 | 1587 | <0.001 |
| Atrial fibrillation (%) | 54.2 (64/118) | 55.1 (39.0–71.3) | 64.8 | 25.548 | 0.002 |
| Functional MR (%) | 43.8 (75/171) | 50.1 (32.0–68.2) | 89.4 | 169.401 | <0.001 |
| Degenerative MR (%) | 53.2 (91/171) | 48.7 (29.4–68.0) | 91.4 | 210.395 | <0.001 |
| Mitral stenosis | 5.8 (10/172) | 4.8 (1.4–8.3) | 15.7 | 22.552 | 0.258 |
| MR >2+ | 92.4 (159/172) | 93.4 (89.2–97.6) | 21.7 | 24.273 | 0.186 |
| Partial clip detachment | 26.6 (33/124) | 31.3 (19.5–43.1) | 51.8 | 25.433 | 0.013 |
| Loss of leaflet insertion | 13.7 (17/124) | 16.6 (6.8–26.5) | 68.3 | 31.567 | <0.001 |
| Surgical characteristics | |||||
| Days after procedure | 214 ± 291 | 330.1 (138.2–522.1) | 100 | 535771 | <0.001 |
| MV replacement (%) | 68.0 (117/172) | 63.5 (49.1–77.9) | 87.1 | 147.556 | <0.001 |
| MV repair (%) | 32.0 (55/172) | 37.3 (22.2–52.4) | 88.4 | 147.340 | <0.001 |
| Mechanical valve (%) | 1.7 (3/172) | 2.8 (0.5–5.0) | 0 | 17.024 | 0.588 |
| Repair planned (%) | 60.0 (45/75) | 57.8 (36.1–79.6) | 78.9 | 47.424 | <0.001 |
| Other associated surgical procedures (%) | 60.4 (104/172) | 57.1 (33.2–80.9) | 96.4 | 539.972 | <0.001 |
| Tricuspid valve repair (%) | 27.9 (48/172) | 31.8 (19.4–44.1) | 78.8 | 89.603 | <0.001 |
| ASD closure (%) | 41.3 (71/172) | 38.2 (13.6–62.9) | 97.3 | 715.530 | 0.002 |
| Surgery success (%) | 98.8 (170/172) | 97.2 (94.9–99.5) | 0 | 6.614 | 0.996 |
| In-hospital outcome | |||||
| Death (%) | 16.3 (23/141) | 15.0 (9.5–20.4) | 0 | 13.398 | 0.767 |
| Acute HF (%) | 14.9 (21/135) | 14.8 (9.3–20.3) | 0 | 15.470 | 0.562 |
| Stroke | 5.1 (6/116) | 6.4 (1.8–11.1) | 0 | 5.812 | 0.990 |
| AKI | 7.3 (5/68) | 8.7 (2.9–4.5) | 0 | 9.875 | 0.771 |
| Inotropic support | 42.3 (25/59) | 41.9 (17.6–66.1) | 83.9 | 68.696 | <0.001 |
| Follow-up | |||||
| Mean follow-up (months) | 13.2 ± 11.3 | 11.9 (3.9–19.8) | 98.9 | 464.440 | <0.001 |
| Death (%) | 27.6 (34/123) | 26.5 (19.2–33.9) | 0 | 8.724 | 0.724 |
Categorical values are expressed as proportions % (n/N) and quantitative measurements as mean ± standard deviation, as appropriate.
AKI: acute kidney injury; ASD: atrial septal defect; CI: confidence interval; HF: heart failure; LVEF: left ventricular ejection fraction; MR: mitral regurgitation; MV: mitral valve; NYHA: New York Heart Association.
Follow-up outcomes
At a mean follow-up of 12 months, we pooled data on 123 patients. The estimated all-cause death was 26.5%, with low heterogeneity among studies. Overall, residual MR was predominantly trivial or mild, and the proportion of surgical mitral valve reinterventions was low, with only 2 patients requiring staged mitral valve replacement after unsuccessful surgical repair. One case of infective endocarditis was reported, whereas no cases of valve thrombosis were observed.
DISCUSSION
Failure of transcatheter mitral valve repair represents a challenging situation with surgical strategies limited by the high-risk profiles of the patients and the low efficacy of redo transcatheter procedures [26]. Pooling data from multiple surgical experiences after transcatheter leaflet repair provides more reliable insight into this heterogeneous scenario and raises several considerations.
Overall, surgical revision after a failed MitraClip procedure was associated with poor in-hospital and post-discharge outcomes, with all-cause mortality reaching 26.5% at the 1-year follow-up, reflecting the baseline risk profile of this cohort. Interestingly, although there was heterogeneity among studies for baseline patients’ characteristics, outcome end points showed no heterogeneity, reinforcing the validity of these findings. Because all the studies retrospectively included surgically managed patients, a comparison with medically treated patients and with patients undergoing redo transcatheter procedures was not available in any publication. This also represents a significant bias because only patients with more favourable profiles may have been selected for surgery.
The previous MitraClip implantation usually jeopardized the possibility of surgical valve repair as shown by the high rate (>60%) of patients who required surgical mitral valve replacement, despite the fact that a repair had been planned in two-thirds of them. Degenerative changes occurring in the leaflets near the clip further complicating the underlying disease, and leaflet laceration or rupture in cases of loss of leaflet insertion and partial clip detachment were the most commonly reported reasons for limited repair feasibility. The number of implanted clips has also been shown to influence valve reparability [22].
These results also highlight the need to rediscuss the term ‘inoperable patient’, because, despite the claimed prohibitive surgical risk, a good proportion of patients survived, although in most cases, a complex cardiac operation associated with concomitant procedures was performed. Furthermore, procedural feasibility resulted acceptable, with a significant proportion of patients presenting with good valve function and free of reintervention at the follow-up examination.
Although a less invasive option may be tempting in patients with significant MR who can be operated with an ‘acceptable’ risk (especially patients with degenerative MR), an initial transcatheter approach should be discouraged for the following reasons: (i) open mitral valve surgery for failed MitraClip procedures is difficult to be indicated in patients who had previously been advised against surgery; and (ii) a failed transcatheter procedure will likely jeopardize the possibility of subsequent valve repair.
These findings confirm that, at the time of mitral valve repair strategy selection, a careful evaluation of surgical risk by the heart team and preoperative comprehensive evaluation of echocardiographic anatomical feasibility criteria for percutaneous repair are of paramount importance, because patients who experience a failed transcatheter intervention may miss out on the possibility of future surgical valve repair and face a poor outcome. There is still much to learn about how to address the challenging situation of failed transcatheter leaflet repair. Further studies comparing medical therapy, surgery and redo percutaneous intervention are warranted.
Limitations
All included studies were retrospective in nature, and inclusion criteria varied across different studies. In addition, publication bias cannot be excluded, especially for case reports. Finally, no medically treated or redo percutaneous mitral valve repair cohorts after failed MitraClip procedure were available as a control group.
CONCLUSION
Surgical intervention after failed transcatheter mitral valve intervention is burdened by high in-hospital and 1-year mortality, which reflects the high baseline risk profile of the patients. Mitral valve replacement is usually required due to leaflet injury.
SUPPLEMENTARY MATERIAL
Supplementary material is available at ICVTS online.
Conflict of interest: None of the authors had a conflict of interest to declare.
Author contributions
Francesco Melillo: Conceptualization; Data curation; Formal analysis; Methodology; Validation; Writing—original draft. Luca Baldetti: Data curation; Methodology; Writing—original draft; Writing—review & editing. Alessandro Beneduce: Writing—review & editing. Eustachio Agricola: Supervision. Alberto Margonato: Supervision. Cosmo Godino: Supervision; Validation; Writing—review & editing.
Reviewer information
Interactive CardioVascular and Thoracic Surgery thanks Peter Verbrugghe and the other, anonymous reviewer(s) for their contribution to the peer review process of this article.
Supplementary Material
Abbreviations
- CI
Confidence interval
- HF
Heart failure
- MR
Mitral regurgitation
REFERENCES
- 1. Puls M, Lubos E, Boekstegers P, von Bardeleben RS, Ouarrak T, Butter C. et al. One-year outcomes and predictors of mortality after MitraClip therapy in contemporary clinical practice: results from the German transcatheter mitral valve interventions registry. Eur Heart J 2016;37:703–12. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 2. Sorajja P, Vemulapalli S, Feldman T, Mack M, Holmes D, Stebbins A. et al. Outcomes with transcatheter mitral valve repair in the United States: an STS/ACC TVT registry report. J Am Coll Cardiol 2017;70:2315–27. [DOI] [PubMed] [Google Scholar]
- 3. Higgins JPT, Altman DG, Gøtzsche PC, Jüni P, Moher D, Oxman AD. et al. The Cochrane Collaboration’s tool for assessing risk of bias in randomised trials. BMJ 2011;343:d5928. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4. DerSimonian R, Laird N.. Meta-analysis in clinical trials. Control Clin Trials 1986;7:177–88. [DOI] [PubMed] [Google Scholar]
- 5. Higgins JPT, Thompson SG, Deeks JJ, Altman DG.. Measuring inconsistency in meta-analyses. BMJ 2003;327:557–60. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 6. Dang NC, Aboodi MS, Sakaguchi T, Wasserman HS, Argenziano M, Cosgrove DM. et al. Surgical revision after percutaneous mitral valve repair with a clip: initial multicenter experience. Ann Thorac Surg 2005;80:2338–42. [DOI] [PubMed] [Google Scholar]
- 7. Rogers JH, Yeo KK, Carroll JD, Cleveland J, Reece TB, Gillinov AM. et al. Late surgical mitral valve repair after percutaneous repair with the MitraClip system. J Card Surg 2009;24:677–81. [DOI] [PubMed] [Google Scholar]
- 8. Argenziano M, Skipper E, Heimansohn D, Letsou GV, Woo YJ, Kron I. et al. Surgical revision after percutaneous mitral repair with the MitraClip device. Ann Thorac Surg 2010;89:72–80; discussion 80. [DOI] [PubMed] [Google Scholar]
- 9. Conradi L, Treede H, Franzen O, Seiffert M, Baldus S, Schirmeret J. et al. Impact of MitraClip therapy on secondary mitral valve surgery in patients at high surgical risk. Eur J Cardiothorac Surg 2011;40:1521–6. [DOI] [PubMed] [Google Scholar]
- 10. Takahashi H, Rauch H, Karck M, Fritz M.. Surgical conversion early after failed percutaneous repair with the MitraClip system. Eur J Cardiothorac Surg 2012;42:1053. [DOI] [PubMed] [Google Scholar]
- 11. Rose D, D'Ascoli R, Chirichilli I, Marullo AG, Toscano M, Miraldi F.. Late MitraClip failure: removal technique for leaflet-sparing mitral valve repair. J Card Surg 2012;27:543–5. [DOI] [PubMed] [Google Scholar]
- 12. Chanda B, Venn GE.. Mitral valve replacement following a failed MitraClip procedure. Eur J Cardiothorac Surg 2012;42:739–40. [DOI] [PubMed] [Google Scholar]
- 13. Pope N, Lim S, Ailawadi G.. Late calcific mitral stenosis after MitraClip procedure in a dialysis-dependent patient. Ann Thorac Surg 2013;95:e113–14. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 14. Wendeborn J, Donndorf P, Westphal B, Steinhoff G.. Surgical double valve replacement after transcatheter aortic valve implantation and interventional mitral valve repair. Interact CardioVasc Thorac Surg 2013;17:909–911. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 15. Alozie A, Westphal B, Kische S, Kaminski A, Paranskaya L, Bozdag-Turan I. et al. Surgical revision after percutaneous mitral valve repair by edge-to-edge device: when the strategy fails in the highest risk surgical population. Eur J Cardiothorac Surg 2014;46:55–60. [DOI] [PubMed] [Google Scholar]
- 16. Monsefi N, Zierer A, Khalil M, Ay M, Beiras-Fernandez A, Moritz A. et al. Mitral valve surgery in 6 patients after failed MitraClip therapy. Tex Heart Inst J 2014;41:609–12. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 17. Cockburn J, Fragkou P, Hildick-Smith D.. Development of mitral stenosis after single MitraClip insertion for severe mitral regurgitation. Catheter Cardiovasc Interv 2014;83:297–302. [DOI] [PubMed] [Google Scholar]
- 18. Caussin C, Diakov C, Dervanian P, Amabile N.. Backward migration of a MitraClip through a patent transseptal orifice. JACC Cardiovasc Interv 2015;8:1907–8. [DOI] [PubMed] [Google Scholar]
- 19. Calafiore AM, Al Abdullah M, Iaco AL, Shah A, Ali Sheikh A, Allam A. et al. Mitral valve replacement after MitraClip therapy. J Card Surg 2015;30:414–18. [DOI] [PubMed] [Google Scholar]
- 20. Saito S, Baraki H, Fleischer B, Kutschka I.. Mitral valve replacement after failed MitraClip™ therapy: report of two cases. J Artif Organs 2015;18:177–80. [DOI] [PubMed] [Google Scholar]
- 21. Frerker C, Kuck KH, Schmidt T, Kreidel F, Bader R, Schmoeckel M. et al. Severe infective endocarditis after MitraClip implantation treated by cardiac surgery. EuroIntervention 2015;11:351–4. [DOI] [PubMed] [Google Scholar]
- 22. Geidel S, Wohlmuth P, Schmoeckel M.. Survival prediction in patients undergoing open-heart mitral valve operation after previous failed MitraClip procedures. Ann Thorac Surg 2016;101:952–8. [DOI] [PubMed] [Google Scholar]
- 23. Elhmidi Y, Voss B, Lange R.. Surgical mitral valve intervention following a failed MitraClip procedure. EuroIntervention 2016;12:Y102–6. [DOI] [PubMed] [Google Scholar]
- 24. Takayuki G, Sören S, Kristin R, Harnath A, Grimmig O, Sören J. et al. Surgical revision of failed percutaneous edge-to-edge mitral valve repair: lessons learned. Interact CardioVasc Thorac Surg 2019;28:900–7. [DOI] [PubMed] [Google Scholar]
- 25. Mkalaluh S, Szczechowicz M, Karck M, Weymann A.. Failed MitraClip therapy: surgical revision in high-risk patients. J Cardiothorac Surg 2019;14:75. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 26. Kreidel F, Frerker C, Schlüter M, Alessandrini H, Thielsen T, Geidel S. et al. Repeat MitraClip therapy for significant recurrent mitral regurgitation in high surgical risk patients. JACC Cardiovasc Interv 2015;8:1480–9. [DOI] [PubMed] [Google Scholar]
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