Real-world evidence for MitraClip

The EXPAND G4 study confirmed the safety and efficacy of the next generation MitraClip NTR/XTR system in primary mitral regurgitation (MR) patients in a real-world setting, according to Dr Scott Lim (University of Virginia, USA) [1].

The 1,000+ patient global EXPAND study is a post-market, multi-centre, single-arm, prospective study to assess the safety and performance of the next generation MitraClip G4 System. Also, it is the first trial to use Echo Core Lab and Clinical Events Committee adjudicated 30-day clinical outcomes in patients with primary mitral regurgitation treated with the next generation NTR and XTR MitraClips.

The primary objective was to determine the percentage of participants with MR reduction to ≤2+ at 30 days. Secondary objectives of the study were to evaluate MR reduction outcomes as a function of mitral valve anatomic complexity and to confirm the safety (including single leaflet device attachments and leaflet injuries) and efficacy of the NTR and XTR systems. Eligible patients had symptomatic MR (≥3+) and were eligible to receive the MitraClip per the current approved indications for use in their respective country of residence. The overall study subject population consisted of 413 subjects with secondary MR aetiology and 422 subjects with primary or mixed aetiology; this last group was the focus of this analysis.

All-cause death occurred in 2.4% of patients, stroke in 1.2% (ischaemic stroke in 1.0% and haemorrhagic stroke in 0.2%), and non-elective cardiovascular surgery for device-related complications in 0.9%. Regarding the device-related leaflet adverse events, single leaflet device attachment occurred in 1.9% and leaflet injury (i.e. leaflet tear or perforation) in 0.2%. It was concluded that approximately one third of patients had a complex mitral valve anatomy, reflecting the difference in patients treated in the real world in comparison with those included in past clinical trials. Results show that MR ≤1+ is being achieved more often with MitraClip NTR and XTR than previously observed in the EVEREST II trials [2]. MitraClip XTR was associated with greater MR reduction compared with NTR in more complex anatomies.

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   1. Lim DS, et al. Abstract 412-12.ACC/WCC 28-30 March 2020.
   2. Feldman T, et al. N Engl J Med. 2011;364(15):1395-1406.

Posted on 8 September 20209 December 2020