Heart failure is a progressive disease and once the process has starte
d it continues with further deterioration of cardiac function or ends
in sudden death. In many patients changes within the heart start to de
velop long before clinical symptoms occur. The left ventricle goes thr
ough a number of adaptions - remodelling - to compensate for increased
pressure or volume load or subsequent myocardial infarction. Several
of these compensatory changes have prognostic implications and indicat
e increased risk of clinical heart failure or cardiac events, Thus, in
creased left ventricular dimensions, volume and mass together with red
uced systolic function are all markers of poor prognosis. Treatment wi
th angiotensin-converting enzyme (ACE) inhibitors before the onset of
clinical heart failure has been shown to improve prognosis. Identifica
tion of individuals al high risk is difficult since signs and symptoms
of heart failure are often lacking. A strategy to find these patients
must use objective methods to characterise the state of the left vent
ricle. It is likely that not only patients with significant reduction
of systolic function but also other signs of impaired left ventricular
dysfunction will benefit from treatment with ACE inhibitors. Only by
preventive treatment may we be able to decrease the number of patients
with new onset of clinical heart failure.