Treatment for chronic CHD.

It seems likely that a number of medical and surgical treatments have had an impact on the overall mortality from ischaemic heart disease in recent years although there is comparatively little data upon which to base conclusions. The two forms of treatment which have been shown, in controlled trials, to reduce mortality are beta blockade after infarction and coronary artery bypass surgery in chronic ischaemic heart disease. It is of interest that these treatments seem to be most often applied in countries that have had the greatest fall in mortality, although it is not suggested that they have played more than a small role. It is likely that other influences on mortality have included the use of pacemakers and the avoidance of previously undesirable medical practices. Much more careful documentation of the use of treatments in different countries is highly desirable.