** Thanks for contacting with your health concern 1. Although stress is directly linked with appearance of acne since both skin and nervous system has similar embryological origin thus if one is affected other is affected as well [psychosomatic] 2. Tachycardia as such has no direct influence on the appearance of acne however it indirectly can contribute to the same and one cause to look out for is Adrenal tumor [where there is high blood pressure, tachycardia, anxiety/emotional imbalance, acne] thus check with an ultrasonography of adrenal glands to exclude the same 3. Otherwise take an opinion of a Cardiologist to rule out any heart problem or other medical condition which can be treated accordingly.