cardiac notch

例句：

1. 1.The heart's cardiac notch is a crucial part of its function.
   心脏的心脏节段是其功能的关键部分。
2. 2.During surgery, the surgeon carefully cuts around the cardiac notch to avoid damaging the heart muscle.
   在手术中，外科医生小心地绕过心脏节段以避免损伤心肌。
3. 3. Cardiac notches are small depressions in the heart wall that can be used to guide the placement of pacemakers.
   心脏壁的小凹陷可以用于引导起搏器的放置。