Transcatheter Edge-to-Edge Repair Increases Annular Forces in In Vitro Whole Heart Preparations

Area of Science:

• Cardiovascular research
• Medical device engineering
• Interventional cardiology

Background:

• Tricuspid transcatheter edge-to-edge repair (TEER) offers therapeutic benefits through an acute annuloplasty effect.
• The precise mechanisms underlying TEER-induced reduction in tricuspid annular size are not fully understood.

Purpose of the Study:

• To quantify the in vitro annular forces generated by TEER in porcine hearts.
• To investigate how different leaflet pair clipping strategies impact these forces.

Main Methods:

• Utilized 49 TEER interventions with MitraClip XT on 13 porcine hearts.
• Assessed forces on the annulus following single-clip (AS, AP, SP) and double-clip (AS-AP, AS-PS, AP-PS) interventions.
• Measured right ventricular pressure, transvalvular flow, and annular forces at eight locations.

Main Results:

• TEER generated significant inward-pulling forces on the tricuspid annulus.
• The AS-PS double-clip intervention produced the maximum annular force.
• Single AS clip intervention yielded the highest force among single-clip procedures, while AP and AS-AP interventions resulted in the lowest forces.

Conclusions:

• The magnitude of TEER-induced annular force is directly influenced by the specific intervention strategy.
• The number of clips implanted significantly modulates the resulting annular forces.