I have a tingling numb feeling in my left four fingers. Is this a sign of a heart attack?

Not usually. More likely nerve compression, but needs to check pulses, thoracic outlet, or central nervous system- stroke.
Usually not. The arm discomfort associated with cardiac issues is mostly present on the inner part of the upper left arm. It is also not usually present as an isolated symptom. That said, if you are concerned, it's best to talk with your doctor and review your risk factors for heart disease.