POTS with sleep apnea

I am a 35 year old female, who had an ablation for Atrial Flutter last fall, and was diagnosed with postural orthostatic tachycardia syndrome 3 months ago.  Family history-grandmother died suddenly in sleep at 49-she had symptoms simular to mine.  Now my Cardioligist thinks I am showing signs of stoping breathing in my sleep(waking up with headaches and heart racing@125-140bpm) He said POTS will only raise heart rate while upright and has ordered a sleep study immediately and said this could be serious.
Questions: 1) I know pots is an atonomic failure, and he said the same type of nerve controls my breathing and that could be related what does that mean I have?

2)Is the cardiologist who I should be seing for an atonomic failure? If not then who?

3)what are the odds I will die young like my grandmother?

[CCF-Neuro-M.D.-CS]

The main innervation to the diaphragm of the lung (primarily responsible for breathing) is the phrenic nerve. This nerve is formed from nerves in the 3rd through 5th cervical levels. The respiratory drive centers are in the brianstem. There are two reasons why someone may not breath properly during sleep. The first is that the airway may collapse and not allow air to be moved, this is what happens in obstructive sleep apnea. The second reason would involve dysfunction of the central repiratory drive centers in the brainstem. A sleep study would be a good test to differentiate these possibilities. To my knowledge the autonomic nerves do not play a major role in breathing. Many cardiologists have experience with autonomic dysfunction. You could also see a neurologist who specializes in autonomic dysfunction. Dr. Robert Shields is our expert at the Cleveland Clinic. I cannot comment on your prognosis without seeing you clinically. I encourage you to obtain a second opinion if you like. Good luck.

[Anne 35]

I forgot- Is it possible that my atrial flutter was caused by POTS, and if so, how likely is it to come back.  I am feeling a that same fluttering in my chest this past week that I did before my ablation, but I have not had a monitor on since it started to verify.  The POTS keeps my heart rate up to 120-140 for hours at a time for days on end (my blood pressure machine also tells me my heart rate), so it is possible that is what I am feeling, but it definatly felt stronger this week two different times for less than a minute.

Where specifically can I get help?

[trhapney]

I am 27 years old and was diagnosed with POTS and NMH and I have the same problem when I sleep at night.  I will wake up gasping for air and my heart rate is racing away.

[Anne 35]

What is NMH? What did your doctor say about your symptoms? Have you had a sleep study to see if you do stop breathing?  How are you functioning with the POTS.  Do any of the medications work for you?

Sorry for all of the questions, but I have not found anyone going through this.