Hello Dr. Samuel, I would like a specialist s opinion over something that s been bothering me for about a week now. I m a 26 year old woman and I have this pressure in the left side of my thoracic cavity, with the origin point moving from beneath the left breast to a little lower and sometimes going towards the back, but still keeping it on the left side. It almost never escalates to being literally a pain, and when it does it s generally very mild and not the type of clawing or needle pain , more like just a mild muscle cramp . Sometimes the pressure can feel as if someone is scratching the surface of the heart, at least that s how I perceive it. Another symptom would be that sometimes when this happens my left arm can get a little numb, I simply don t feel it the same as the left, but the numbness never spreads. My pulse is also rapid during these episodes, which generally last for hours and become more troublesome in the evening, but nothing severe, I can still sleep properly. I put it on the fact that we ve been constantly experiencing high temperatures where I live, up to 41degrees Celsius in the shade, and I am the type of person who not only doesn t stand heat all that well, but I also have a mild to severe case of pectus excavatum , therefore my heart lies more on the left side of my thoracic cavity and my lungs have a lower capacity than normal. I had my last cardiac check-ups less than a year ago and they came out ok. I don t get panic attacks from this condition, at least I don t find myself worrying all the time over it, but it s becoming stressful and I don t really know the cause for it. Also having had a father who died of aorta rupture at 45 and potentially might ve suffered from Marfan syndrome - had a lot of the signs - doesn t do much to help things, even though as I ve said all my cardiac tests got out ok, including my aorta measurements. So I would really like to ask for your advice and opinion on this. Should I wait a couple more days until I do some cardiac tests again, until this heatwave passes for good? Or should I worry about something more serious? Thank you very much upfront for all your help. Respectfully, Luciana