Mitral Valve Prolapse,anxiety,and Marijuana

Hello, I am a 21 year old with symptomatic Mitral Valve Prolapse. I experience fatigue, nervousness, anxiety, panic attacks, chest pain, insomnia, fast heart rate, and awareness of the heart. I have smoked marijuana for the last 7 years (on and off) and have only seldomly (mostly in the beginning) had adverse affects to it. Recently (in the last 8 months or so), I have had severe panic attacks and anxiety after smoking very small amounts. Way less than I used to anyway. Does this mean that the muscles in my heart have worsened or become more weak causing me to have severe anxiety. I literally feel like I am dying when this happens, its really frightening.