Is there any connection between heart beat too fast with atherosclerosis, or unrelated?

Not necessarily: Generally poor physical fitness, obesity, smoking and diabetes can be associated with a higher heart rate and more importantly lesser heart rate variability. These also happen to be risk factors for atherosclerosis. Higher heart rate may also be due to anxiety, anemia, dehydration, hyperactive thyroid and simply a normal variation which are unrelated to atherosclerosis.