Introducer Development for Coronary Sinus Access From Parasternal Mediastinotomy

Area of Science:

• Cardiovascular Surgery
• Medical Device Engineering
• 3D Printing Applications

Background:

• Right parasternal mediastinotomy is established for pacemaker insertion.
• Accessing the coronary sinus via this approach is challenging due to a lack of specialized introducers and techniques.
• This method could enable biventricular pacing and other interventions when conventional routes fail.

Purpose of the Study:

• To develop and evaluate novel introducers for coronary sinus access using a parasternal mediastinotomy approach.
• To investigate the feasibility of using patient-specific CT data for custom introducer design.

Main Methods:

• Anatomically derived introducers were designed using 3D modeling and printing based on CT scans in pigs.
• Surgical procedures in pigs demonstrated coronary sinus lead insertion with custom introducers.
• Patient CT scans were analyzed to define optimal introducer curvatures and dimensions for human anatomy.

Main Results:

• Fifty-one distinct introducer paths were defined, optimizing for anatomic feasibility and material constraints.
• Key dimensions for introducers were established: average distance 67 mm, bend angle 47°, hook angle 39°, twist angle 20°.
• A prototype cannula demonstrated successful fit in a human postmortem specimen.

Conclusions:

• Parasternal mediastinotomy provides feasible access to the coronary sinus for cardiac resynchronization, mitral annuloplasty, and instrumentation.
• Patient-specific CT data can effectively guide the design of introducers for clinical application.