Preoperative loop length determination for mitral valve repair by 4-dimensional computed tomography

Area of Science:

• Cardiovascular Surgery
• Medical Imaging
• Cardiac Valve Repair

Background:

• The loop technique for mitral valve repair traditionally involves intraoperative chordal length measurements during cardiac arrest, which can be time-consuming and lack reproducibility.
• This often leads to challenges in achieving optimal loop bundle length, potentially impacting repair success.

Purpose of the Study:

• To determine the optimal loop length preoperatively using 4-dimensional computed tomography (4D CT) for mitral valve repair.
• To enhance the accuracy and reproducibility of the loop technique in mitral valve repair.

Main Methods:

• Loop length was preoperatively determined using 4D CT by measuring the distance from the papillary muscle head to the free margin of the nonprolapsing leaflet.
• Measurements were performed on commissural and long-axis views in the late systolic phase.
• The technique was applied to 45 consecutive patients undergoing mitral valve repair with the loop technique.

Main Results:

• A total of 55 loop bundles were created in 45 patients, with loop lengths ranging from 16 to 26 mm (median 19 mm).
• Mitral valve repair was successfully completed in all patients, with predetermined loop lengths used successfully in 93.3% of cases.
• Postoperative echocardiography showed none/trace regurgitation in 41 patients and mild regurgitation in 4, with no hospital mortality or major complications.

Conclusions:

• Preoperative 4D CT measurements provide an accurate and reproducible method for predicting the required loop length in mitral valve repair.
• This approach can streamline the loop technique, potentially improving surgical outcomes and patient recovery.