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).
In all other quadrupedal vertebrates, the pelvic vertebrae undergo a similar developmental process to form a sacrum in the adult, even while the bony tail (caudal) vertebrae remain unfused. The number of sacral vertebrae varies slightly. A horse will fuse S1âS5, but a dog will fuse S1âS3.