Maybe. In many cases the answer is no. In some cases there may be signs of underlying coronary artery disease. So increasing episodes of chest pain, chest pressure, or chest fullness maybe associated with shortness of breath, nausea . If this discomfort is provoked by exertion and becomes increasingly easy to provoke and even occurs at rest, this is a potential sign of trouble and needs evaluation.
Not always... Sudden cardiac death can occur without any preceding symptoms. Cardiac arrest can also occur during an acute myocardial infarction (heart attack) in which case there is usually chest pain, shortness of breath, etc. So, sometimes there are no preceding symptoms and other times there are preceding symptoms.
Heart stops... In cardiac arrest, the heart stops beating. So, the person will be unconscious, unarousable and have no pulse and not be breathing. The person is clinically dead and CPR needs to be performed immediately and an AED used, if available. Call 911 immediately and they will instruct you on what to do before professional help arrives. Read more...