Considerations on the left papillary muscles microangioarchitecture.

Area of Science:

• Cardiovascular Anatomy
• Cardiac Surgery
• Medical Imaging

Background:

• The papillary muscles are crucial for heart valve function.
• Understanding their blood supply is vital for cardiac procedures.
• Existing anatomical data on left papillary muscle vascularization is limited.

Purpose of the Study:

• To provide detailed macroscopic and microscopic evidence of the blood supply to the left papillary muscles in human hearts.
• To identify the specific coronary arteries supplying the left anterolateral and posteromedial papillary muscles.
• To elucidate the vascular architecture and perfusion patterns within the left papillary muscles.

Main Methods:

• Dissection of 20 adult human hearts without cardiac history.
• Injection of China ink into coronary arteries of 10 hearts for macroscopic visualization.
• Diaphanization of left papillary muscle samples for microscopic analysis.
• Detailed examination of arterial sources and microvascular networks.

Main Results:

• Left anterolateral papillary muscles consistently supplied by the left coronary system (anterior interventricular, diagonal, and marginal arteries).
• Left posteromedial papillary muscles primarily supplied by the right coronary system (70%) or left coronary system (30%).
• Papillary muscles receive supply from one or two main longitudinal arteries, with contributions from mural networks and segmental anastomoses.

Conclusions:

• The study clarifies the dual vascular supply of left papillary muscles, highlighting variations in the posteromedial muscle.
• Overlapping vascular territories and high capillary density ensure robust blood perfusion.
• This detailed vascular anatomy is essential for cardiologists and cardiac surgeons.