Author + information
- Maurizio Taramasso, MD∗ (, )
- Hannes Alessandrini, MD,
- Shingo Kuwata, MD,
- Luigi Biasco, MD,
- Fabian Nietlispach, MD, PhD,
- Oliver Gaemperli, MD,
- Michel Zuber, MD,
- André Linka, MD,
- Giovanni Pedrazzini, MD,
- Felix Kreidel, MD,
- Christian Frerker, MD,
- Karl-Heinz Kuck, MD and
- Francesco Maisano, MD
- ↵∗Department of Cardiovascular Surgery, University Hospital Zurich, Raemistrasse 100, 8091 Zurich, Switzerland
Implantation of an Amplatzer Closure Device (St. Jude Medical, St. Paul, Minnesota) has been successfully used to treat residual mitral regurgitation (MR) after MitraClip (Abbott, Abbott Park, Illinois) implantation in selected situations to obliterate the residual jet. Different types and sizes of devices have been used, with acute satisfactory results (1,2). However, mid-term results of this technique are unknown.
Between September 2014 and October 2016, 402 high-risk patients underwent MitraClip implantation at 3 centers in Europe. This report describes the outcome of 13 patients (3.2%) among them who underwent deployment of an Amplatzer closure device to treat residual significant MR.
Deployment of an Amplatzer Occluder Device was performed when the implantation of an additional clip was deemed unfeasible because of limited space (“intraclip” or close commissural jet) or because of the mechanism (“intraclip” cleft-like indentation of leaflet perforation). Type and size of the device were based on the location, anatomy, and dimension of the “defect” assessed by transesophageal echocardiography and fluoroscopy. In most of the cases an Amplatzer VSD Occluder was used (Figure 1). In all but 4 cases, the procedure was performed directly during the index MitraClip procedure.
Procedural data are listed in Table 1.
The device was successfully deployed in all cases (procedural time 179 ± 61 min). Adjunctive time to implant the device was 28 ± 7 min. Residual MR was significantly reduced in all cases. No intraprocedural complications occurred.
Despite satisfactory procedural results, in-hospital mortality was 23% (n = 3: 1 patient with paracommissural implantation had a dislocation of the Amplatzer device on the second post-procedural day and died after rescue open-heart surgery; 1 patient with dislocation of the Amplatzer device and severe recurrent MR died of multiorgan failure 4 days after the index procedure; and 1 patient with severe left ventricular dysfunction and severe pulmonary hypertension died due to severe hemolysis despite minimal residual MR). Two more patients died within the first 30 days (1 acute renal failure secondary to hemolysis and 1 sudden death), for an overall 30 days mortality of 38%. According to the Mitral Valve Academic Research Consortium (MVARC) definition, device success and procedural success at 30 days were achieved only in 38%.
During a median follow-up of 8 months, device dislocation was documented in 3 patients (23%); in 2 cases, dislocation was observed a few days after the procedure (2 and 4 days, respectively), whereas in 1 case, it was delayed (6 months after the procedure) (Figure 2). Moreover, 6 patients (46%) developed signs and symptoms of hemolysis during follow-up (Figure 3). A total of 3 patients underwent open-heart surgery during follow-up: 2 due to device dislocation and 1 due to severe hemolysis. Intraoperative inspection revealed almost no endothelialization of the device 6 months after the implant (Figure 4).
Only 3 of 13 patients (23%) did not experience any adverse events and are in good clinical condition at follow-up (6 months, 2.5 years, and 2 years, respectively).
Kubo et al. (3) recently reported satisfactory acute outcomes in a series of 9 consecutive patients who received an Amplatzer Duct Occluder (ADO) II to manage significant MR after MitraClip implantation.
Over a period of 2 years, we used this technique only in 3.2%, suggesting that significant residual MR that could not been treated with conventional methods (further clip, surgical conversion, or conservatively) is a rare event.
These results show that the outcomes of this technique are actually poor, even if the short-term result in terms of MR reduction is good.
The most common complications observed were dislocation of the device and hemolysis, both of them directly related to mortality.
Kubo et al. (3) did not report cases of hemolysis (but only 5 patients have laboratory and echo cardiography at 30 days) using the ADO II, which has a really small caliber mesh. We did not use ADO II, because we strongly believe that the smaller the caliber of the mesh, the higher the expected risk of hemolysis. A second possible mechanism of hemolysis is the elevated flow acceleration, which is observed between the device and the ventricular side of the clips. This is observed in almost all the cases, and it is due to a “maladaptation” of the device with the ventricular side of the clip, and could predispose to dislocation and recurrent MR.
Another open issue remains the incomplete endothelialization at follow-up, suggesting that the perpendicular direction of flow through the device as it is positioned could prevent its sealing, leading to residual MR and risk of thrombosis.
Based on these results, the technique has been largely abandoned at all 3 centers, and we would like to discourage operators from performing it.
To conclude, this technique should be generally avoided and should be taken in consideration only as bailout strategy when no other therapeutic options are feasible.
Please note: Dr. Taramasso is a consultant for St. Jude Medical and 4Tech. Dr. Nietlispach is consultant for St. Jude Medical, Edwards Lifesciences, and Medtronic. Dr. Kuck is consultant for Biosense Webster, St. Jude Medical, Stereotaxis, and Medtronic. Dr. Maisano is a consultant for Medtronic, St. Jude Medical, Abbott Vascular, and Valtechcardio; has received grants from Abbott Vascular, Medtronic, St. Jude Medical, and Edwards Lifesciences; receives royalties from Edwards Lifesciences; and is cofounder of 4Tech, Affix, and Transseptal Solutions. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose. The first 2 authors contributed equally to this work and should be considered both as joint first authors.
- 2017 American College of Cardiology Foundation
- Alkhouli M.,
- El Sabbagh A.,
- Villarraga H.R.,
- Hagler D.J.,
- Rihal C.S.,
- Eleid M.F.
- Kubo S.,
- Cox J.M.,
- Mizutani Y.,
- et al.