Hello and thank you for using HCM. I carefully read your question and i understand your concern. I will try to explain you something. The RSR pattern in your Electrocardiogram doesn t mean any pathology. It is an electrical pattern of your heart, and very typical in people having ASD as you tell. We can not diagnose a valvular issue through electrocardiogram. The valvular situation and congenital defects are seen and diagnosed through echo-cardigraphy. Mitral regurgitation means valvular leakage. It is the same thing. You may say that a valve is leaking and the medical term for this is regurgitation . So, if you already know this, you should not be worried. A mitral valve leakage gives heart murmur s. To say if this is serious or not depends on the severity of the leakage or regurgitation. It might be minimal, mild or sever.It might be serious if it is sever but you can know this only after doing an echo-cardiography. Heart palpitations are nothing to be worried about. They are quite normal at you age or in stressful situations as you say. If I was your treating doctor i would recommend a control echo-cardiogram to evaluate the mitral valvular leaking and if it is minimal or mild you don t have to worry, is nothing serious but just monitor it time after time. Hope I was helpful. Best regards.