A heart attack may not always have the obvious symptoms, there can be certain subtle signs that are very easy to miss. As per the American Heart Association, cardiovascular disease is the leading global cause of death, accounting for more than 17.3 million deaths per year
, a number that is expected to grow to more than 23.6 million by 2030. A new research reveals that nearly half of all heart attacks may not have classic symptoms, such as chest pain, shortness of breath and cold sweats but are likely to be silent. A silent heart attack occurs when blood flow to the heart muscle is severely reduced or cut off completely.