In a healthy heart can strong emotions such as fear, anger, anxiety and a rxn to a natural disaster cause a heart attack or cardiac arrest? :(

Unlikey: Need other issues-atherosclerosis and risk factors smoking, obesity, sedentary lifestyle, diabetes, etc.

Yes: There is a condition caused "broken heart syndrome, " where someone can get cardiac arrest from severe stress or emotions. It is quite rare, but it can happen. It is caused by the surge of stress hormones, like adrenaline, that can be released from severe stress. I must stress - no pun intended - that it is rare, but it can happen, and I have seen it happen.

Broken Heart: "Acute stress cardiomyopathy" is a condition which mimics heart attack. It can cause severe heart complications including heart failure and death. The diagnosis is generally made by the history (a sudden severe emotional or physical stress followed by chest symptoms) and the finding of heart muscle dysfunction (often in Takotsubo pattern) and no coronary artery occlusion to explain it.

Rarely: Although very uncommon, sudden cardiac arrest has occured in people with healthy hearts when sudden severe emotional trauma has occurred.