Edge-to-edge mitral valve repair can be done by a less invasive percutaneous implantation of a clip (MitraClip) that grasps and approximates the edges of the mitral leaflets at the regurgitant jet orifice. This technology was developed in an attempt to imitate the surgical approach for mitral repair, which involves approximation of the mitral leaflets with a suture to create a double orifice . Our study describes and analyze the Egyptian very first experience using the MitraClip in repairing significant MR. We intended to evaluate this therapy in patients having grades 3-4 MR with high surgical risk. Most of our patients presented with impaired LV function or high burden of comorbidities.
Baseline clinical characteristics
Regarding demographic data, NYHA class and EuroSCORE, the study results were in line with Tamburino et al.  who reported that 31 patients were involved in their study [age 71 (IQR 62-79) years, male 81%].
Fifty eight percent (18 of our patients) presented with functional disease and 13 patients (42%) presented with organic degenerative disease. Among patients with functional MR, 67% had a previous old history of coronary artery disease.
Moreover, Sürder et al.  reported that the median age of their patients was 77 years, 67% of them were males, 62% of them were NYHA III, and 20% of them were NYHA IV. Ailawadi et al.  found that 62% of the studied patients were NYHA III and 21% of them were NYHA IV. However, Gaemperli et al.  found that the mean age of their patients was 78 years and 58% of them were males. The type of MR was degenerative in 16 (48%), functional in 15 (45%), and mixed in 2 (6%) patients.
The present study showed that patients varied for their HAS-BLED score with a median value of 1 (range, 0-4). Coronary angiography showed that 35% of our patients had previous PCI, while 45% had normal coronary anatomy. These results were supported by Feldman et al.  who reported that among patients with functional MR, there was a history of coronary artery disease in 74% and previous bypass surgery in 43%.
In the current study, patients had significant improvements in their NYHA class and echocardiographic assessments following MV clipping. These results were supported by Khamis et al.  who reported an improvement in the MR severity in all patients as assessed acutely after MV repair by MitraClip system. Moreover, Whitlow et al.  reported that the MitraClip device reduced MR in the majority of patients deemed at high risk of surgery, resulting in an improvement in clinical symptoms and significant LV reverse remodeling over 12 months.
Additionally, Herrmann et al.  reported acute procedural success, safety, and 1-year efficacy with MitraClip therapy similar for patients with and without AF.
Furthermore, Armstrong et al.  concluded that subjects with thicker anterior mitral leaflets and more significant mitral incompetence were more likely to receive 2 MitraClip devices. Immediate and long-term reductions in MR were similar regardless of the number of devices implanted at the time of the procedure. According to Foster et al. , patients with pre-existing LV dysfunction demonstrated reverse remodeling and improved LV ejection fraction at 12 months after percutaneous MV repair with the MitraClip device. Furthermore, Gonzalez et al.  stated that MitraClip has become available as a treatment option for MR in high-risk surgical patients as it has been showing a high safety profile and a good middle-term effectiveness performance.
Clinical outcome and follow-up
Our study has demonstrated that MitraClip device therapy is reliable, applicable, and effective, with procedural success achieved in almost all patients (100%). There was no procedural mortality or MAE at 30 days. Successful placement of the MitraClip device was associated with a reduction in MR severity by ≥ 2 grades in all patients. The present study showed significant improvements in patients’ right-side heart failure symptoms and their laboratory values following MV clipping. However, AF status did not change significantly. These results were in line with Tamburino et al.  who reported an improvement of clinical symptoms in all patients after percutaneous MV repair with the MitraClip system. Furthermore, Ailawadi et al.  concluded that transcatheter MV repair with the MitraClip in patients with secondary MR was associated with acceptable safety, reduction of MR severity, symptom improvement, and positive ventricular remodeling.
In the present study, four (20%) patients developed complications. These included two cases of bleeding that needed blood transfusion, one case of ischemic CVA, and another one who developed partial clip detachment at 30 days after the procedure.
The current study showed that there was no significant difference between patients who developed complications and those who did not regarding their age, gender, BSA, MR etiology, and NYHA pre- or post-mitral clipping. However, EuroSCORE was higher in the complicated group. These results were supported by Hellhammer et al. . They found no statistical significance between diabetic patients who developed complications and those who did not with respect to age, gender, and MR etiology after percutaneous MV repair with the MitraClip system.
In the present study, follow-up of the patients at 1 month, 6 months, and at 1 year following mitral valve clipping revealed significant improvement of the MR grade, NYHA class, and EF. This emphasizes 1-year efficacy of the MitraClip system. These results coincide with a systematic review of 16 studies including 2980 patients who underwent MitraClip implantation for moderate to severe MR. It concluded persistent MR reduction in 85.3% of the patients at 30-days follow-up and in 86.9% at a mean follow-up of 310 days (ranging from 80 days to 4 years) . Likewise, follow-up of patients with functional MR who underwent MitraClip implantation showed significant improvement of MR grade, EF, and functional capacity according to NYHA class at 12 months compared to the preoperative values . Moreover, Polimeni et al. have recently concluded that LVEDVi and NYHA class are predictors of rehospitalization for heart failure or cardiovascular death in patients having MitraClip system. Thus, the continued effective MR reduction with improved NYHA class for 1 year in our study could increase the survival and reduce the rehospitalization rate in MR patients .
Limitations of the study
Small sample of patients included in our non-randomized study was a main limitation. In addition, due to the novelty of the technique, only a long-term follow-up was documented. Larger series and longer follow-up are warranted to determine the safety, efficacy, and durability of the MitraClip system, enabling further investigation on different patient populations including patients with functional and degenerative MR etiology.
Transcatheter edge-to-edge mitral valve repair of severe MR carries high efficacy and safety especially at high-risk patients for surgical mitral valve replacement.