Cardiovascular medicine is fortunate to have a wealth of clinical trials providing a solid evidence base from which the clinician can make an informed choice of appropriate, efficacious and cost-effective therapies. This trend will continue because of the growing commitment worldwide to the principles of evidence-based medicine.

The progressive fall in age-adjusted cardiovascular mortality, which has been one of the remarkable success stories of the last 25 years, will continue in this millennium. However, even with this improvement, because of the ageing of the population, the total burden of cardiovascular disease on the health care system and on society will continue to increase.

Nowhere will this be more evident than with cardiac failure. Clinical trials will continue to provide evidence of therapies which reduce mortality and need for hospitalisation. However, producing a clinically meaningful improvement in quality of life in this terrible disease may remain an elusive goal. This is because none of our therapies, other than heart transplantation, has so far managed to influence the fundamental problem of loss of myocardium.

There is the potential for molecular biological techniques to address this issue. Myocardial cells have always been considered as terminally differentiated, from shortly after birth. By unlocking the secrets of the processes which control cell differentiation and division, scientists will soon be able to produce new myocardial cells. This will be the first step in a process which has the potential, in the longer term, to repair the damaged heart.

However, it is in the area of pathogenesis and pathophysiology of disease that these molecular approaches will have their greatest impact. Scientists are just starting to reap the rewards from studying animals with either selective deletions or selective over-expression of specific genes. This allows them to test hypotheses about the role of the gene and its product in the pathogenesis of particular diseases.

P. J. Fletcher

Professor of Cardiovascular Medicine, and Director, Cardiovascular Department, John Hunter Hospital, Newcastle, N.S.W.