I am no doctor but I have found out that it does not matter how healthy and/or fit you are a heart problem can start at any moment. I was a competitive athlete (triathlons, adventure racing, marathoner) and training for my third Ironman Triathlon when I started have problems (dizziness, shortness of breath). My EKG came back with a Long QT symptom and further tests revealed Ventricular Tachycardia (lower left chamber of heart). I now have a pacemaker/defibrillator implanted and am scheduled for an ablation since the medication is not helping (I have went into VFIB or cardiac arrest on multiple occasions). Hopefully you get to see an electrophysiologist so they can properly read your EKG and get you the best treatment. As I am finding out, heart problems are not something to take lightly. Best of luck and stay positive.
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