A near death experience is a very powerful experience when it happens to you in your waking life. When it happens in your dream life, its importance is not diminished. There are many possible meanings for this. One of them is that you are experiencing a significant transformation in your real life, one so huge that you will come out of it a completely different person. The old you is dying, and a new you will emerge. This is also a very suggestive symbol of a past life regression.
If you have a near death experience in a dream, you could be using your dreams as a portal to connect to another life time, or revisit memories from a lifetime. Sometimes this is even a visit to your next lifetime. Another common example is that you are going back to an old way of life, rather than rebirthing one. You may be revisiting old habits, like smoking or something of that sort.
You may also be given a message that you are about to have a second chance at something. If your relationship survives a huge trauma for example, you may experience a near death dream experience as the signal that your relationship will be near death, but will ultimately survive in the long run