Sun exposure & heart probs

does anyone else get chest pain when they are out in the sun? Kind of feels like my lungs swell up. I try and keep out of the sun but it's almost impossible with a toddler during summer time. Also wondering if anyone developed SVT or Sinus Tacchy or AFIB with MCTD. I'm due for an ablation in Aug and nervous that it won't be much help. How was your experience? I'm on metropolol now for my heart.