Heart block typically causes lightheadedness, fainting, and palpitations. Depending on the severity of the heart block, this can be dangerous. For example, a third-degree heart block can worsen pre-existing conditions, such as heart failure. It can cause loss of consciousness and even sudden cardiac arrest. There can also be chest pain.
Sacral vertebrae: There are 5 sacral vertebral bones. They are represented by the symbols S1 through S5 and are situated between the lumbar vertebrae and the coccyx (the lowest segment of the vertebral column).The sacral vertebrae are normally fused to form the sacrum.hey are represented by the symbols S1 through S5 and are situated between the lumbar vertebrae and the coccyx (the lowest segment of the vertebral column).
The sacrum is formed by the fusion of 5 (sometimes 6) vertebrae known as the sacral vertebrae named as S1 to S5. Initially they exist as separate vertebrae, and begin to fuse after the age of 18. The fusion completes between the ages of 25 to 33. The last segment of the vertebral column is a structure called coccyx or tailbone, and represents a vestigial tail in humans. It is formed by the fusion of four small vertebrae designated as Co1 to Co4.