The natural history and prognosis of diastolic cardiac failure are difficul
t to determine because of the large differences in the studies which have b
een performed in this field.
The ten studies published to date concerning the prognosis have been perfor
med on hospital populations and, consequently, only the most severe cases h
ave been recruited. Moreover, the threshold values of indices of the ejecti
on phase used to define systolic dysfunction vary from one study to another
.
A review of these papers provides a rather disconcerting appreciation of th
e annual mortality rate (from 1.3% to 17.5%). The differences in aetiology,
age and threshold values of parameters of systolic function probably expla
in most of the variability observed.
Taking unbiased studies alone in consideration, such as the Framingham stud
y, the mean annual mortality of diastolic cardiac failure between 55 and 71
years, is 3 to 9%, much less than that observed with predominantly systoli
c dysfunction (15 to 20%).
Other prospective studies, adjusting morbidity and mortality to age and oth
er principal prognostic factors, are awaited.