Percutaneous mitral valve repair with the MitraClip system: acute results from a real world setting

Abstract

Aims: This study sought to evaluate the feasibility and early outcomes of a percutaneous edge-to-edge repair approach for mitral valve regurgitation with the MitraClip system (Evalve, Inc., Menlo Park, CA, USA). METHODS AND RESULTS PATIENTS: were selected for the procedure based on the consensus of a multidisciplinary team. The primary efficacy endpoint was acute device success defined as clip placement with reduction of mitral regurgitation to < or =2+. The primary acute safety endpoint was 30-day freedom from major adverse events, defined as the composite of death, myocardial infarction, non-elective cardiac surgery for adverse events, renal failure, transfusion of >2 units of blood, ventilation for >48 h, deep wound infection, septicaemia, and new onset of atrial fibrillation. Thirty-one patients (median age 71, male 81%) were treated between August 2008 and July 2009. Eighteen patients (58%) presented with functional disease and 13 patients (42%) presented with organic degenerative disease. A clip was successfully implanted in 19 patients (61%) and two clips in 12 patients (39%). The median device implantation time was 80 min. At 30 days, there was an intra-procedural cardiac tamponade and a non-cardiac death, resulting in a primary safety endpoint of 93.6% [95% confidence interval (CI) 77.2-98.9]. Acute device success was observed in 96.8% of patients (95% CI 81.5-99.8). Compared with baseline, left ventricular diameters, diastolic left ventricular volume, diastolic annular septal-lateral dimension, and mitral valve area significantly diminished at 30 days.

Conclusion: Our initial results with the MitraClip device in a very small number of patients indicate that percutaneous edge-to-edge mitral valve repair is feasible and may be accomplished with favourable short-term safety and efficacy results.

Figures

Figure 1

Bicaval and modified short-axis transoesophageal echocardiographic views. Transseptal puncture performed by means of the Brockenbrough needle.

Figure 2

Post-procedural imaging of the mitral valve after clip deployment. The newly created double-orifice is indicated by arrows in the three-dimensional (A) and two-dimensional echocardiographic views (B). Echoes generated by the clip grasping the leaflets (*) are evident below the mitral annulus plane in the two-dimensional view.

Figure 3

(A) Two-chamber transesophageal echocardiographic view. Colour-Doppler examination shows severe mitral regurgitation from the left ventricle (LV) to the left atrium (LA). The two-dimensional image shows a free-floating chord and the major degree of prolapse of the posterior leaflet in the LA. (B) Two-chamber transoesophageal echocardiographic view. The colour-Doppler image demonstrates a significant reduction of the mitral regurgitation after the successful implantation and release of two clips (arrow). (C) The fluoroscopy right anterior oblique projection shows the two clips attached to the mitral valve leaflets. The second clip is going to be released from the delivery catheter system.

Figure 4

Pulmonary wedge pressure recorded in basal condition shows a high V wave (A) secondary to severe mitral regurgitation. After clip implantation, the V wave is reduced (B). The parallel A-wave reduction indicates diminished end-diastolic pressure. These variations in aggregate result in diminished mean wedge pressure after clip implantation. In this case example, the systemic pressure varied from 100/60 mmHg before clip implantation to 130/70 mmHg after clip implantation, following fluid challenge and norepinephrine administration.

Figure 5

The learning curve of the study series displayed a non-significant reduction of the device time throughout the study, which was also consistently seen in one- and two-clip cases.

Figure 6

Baseline and 30-day mitral regurgitation grading.