The commonest cause of death in the sophisticated world -
Coronary heart disease (Ischemic heart disease) 

CHD is defined as "impairment of heart function due to inadequate blood flow to the heart compared to its needs, caused by obstructive changes in the coronary circulation to the heart".
It is the most common cause of death in developed countries and account for 25-30% of deaths.
CHD is modern epidemic, i.e. a disease that affects populations, not an unavoidable attribute of ageing.
Ischemic heart disease
Accidents
Infectious disease
None of the above